muddy run pumped storage project (ferc no. 2355) - Exelon ...

BEFORE THE FEDERAL ENERGY REGULATORY 

COMMISSION 

APPLICATION FOR NEW LICENSE FOR MAJOR WATER 

POWER PROJECT-EXISTING DAM 

MUDDY RUN PUMPED STORAGE PROJECT 

FERC PROJECT NUMBER 2355 

Volume 1 of 4 

INITIAL STATEMENT 

EXHIBIT A – PROJECT DESCRIPTION 

EXHIBIT B – PROJECT OPERATIONS AND RESOURCE UTILIZATION 

EXHIBIT C – CONSTRUCTION HISTORY AND PROPOSED CONSTRUCTION SCHEDULE 

EXHIBIT D – STATEMENT OF COST AND FINANCING 

EXHIBIT E – ENVIRONMENTAL REPORT 

EXHIBIT F – GENERAL DESIGN DRAWINGS AND SUPPORTING DESIGN REPORT 

EXHIBIT G – PROJECT BOUNDARY MAPS 

EXHIBIT H – PLANS AND ABILITY OF APPLICANT TO OPERATE THE PROJECT 

August 2012

MUDDY RUN PUMPED STORAGE PROJECT (FERC NO. 2355) 


INITIAL STATEMENT PER 18 CFR § 4.51 

APPLICATION FOR NEW LICENSE MAJOR WATER POWER PROJECT - EXISTING DAM 

(1) Exelon Generation Company, LLC (“Exelon” or “Applicant”) applies to the Federal Energy 

Regulatory Commission (“Commission” or “FERC”) for a new license for the existing Muddy 

Run Pumped Storage Project (“the Project”), FERC Project Number 2355, as described in the 

attached Exhibits. The current license for the Muddy Run Project was issued on September 21, 

1964 and expires on August 31, 2014. 

(2) The location of the Project is: 

State: Pennsylvania 

Counties: York and Lancaster 

Townships: Drumore, Martic and Peach Bottom 

Stream: Muddy Run 

(3) The exact name, address, and telephone number of the Applicant are: 

Exelon Generation Company, LLC 

300 Exelon Way 

Kennett Square, PA 19348 

Tel: (610) 765-5959 

The exact name, address, and telephone number of each person authorized to act as agent for the 

Applicant in this application are: 

Colleen E. Hicks 

Manager Regulatory and Licensing, Hydro 

Exelon Power 



Tel: (610) 765-6791 

Colleen.hicks@exeloncorp.com 

Kathleen Barrón 

Vice President 

Federal Regulatory Affairs and Wholesale Market Policy 

Exelon Corporation 

101 Constitution Ave. 

Washington, DC 20001 

Tel: (202) 347-7500 

Kathleen.Barron2@exeloncorp.com 

(4) The Applicant is a domestic corporation and is not claiming preference under section 7(a) of the 

Federal Power Act, 16 U.S.C. 796. 

i



(5) (i) The statutory or regulatory requirements of the state(s) which affect the Project as it exists with 

respect to bed and banks and the appropriation, diversion, and use of water for power purposes, 

and with respect to the right to engage in the business of developing, transmitting, and 

distributing power and in any other business necessary to accomplish the purpose of the license 

under the Federal Power Act, are: 

� Applicant is subject to Water Quality Certification from the Pennsylvania Department of 

Environmental Protection and Section 401 (a)(1) of the Clean Water Act. 

(5) (ii) The steps which the Applicant has taken or plans to take to comply with the regulations cited 

above are: 

� The Applicant will submit a request for Water Quality Certification from the Pennsylvania 

Department of Environmental Protection. Since this is an application for a new license for an 

existing waterpower project, the Applicant expects to continue to operate the facility pursuant 

to approvals, licenses, permits, and exemptions already in effect. 

(6) Exelon owns the existing Project facilities; there are no federally owned or operated facilities 

associated with the Project. 

ii



ADDITIONAL INFORMATION REQUIRED BY 18 C.F.R. § 5.18(A) 

(1) Identify every person, citizen, association of citizens, domestic corporation, municipality, or 

state that has or intends to obtain and will maintain any proprietary right necessary to 

construct, operate or maintain the project: 

Exelon Generation Company, LLC, a Pennsylvania limited liability company, currently owns and 

will continue to maintain all proprietary rights necessary to construct, operate and maintain the 

Project. 

(2) Identify (providing names and mailing addresses): 

(i) Every county in which any part of the project and any Federal facilities that would 

be used by the project would be located; 

York County 

100 W Market Street 

York, PA, 17401 

(ii) Every city, town, or similar local political subdivision: 

iii 

Lancaster County 

50 North Duke Street 

Lancaster, PA. 17608 

i. In which any part of the Project, and any Federal facility that would be used by 

the project, would be located; or 

Martic Township 

370 Steinman Farm Road 

Pequea, PA 17565 

Drumore Township 

1675 Furniss Road 

Drumore, PA 17518-9768 

Peach Bottom Township 

545 Broad Street Extended 

Delta, PA 17314 

Lower Chanceford Township 

4120 Delta Road 

Airville, PA 17302 

ii. That has a population of 5,000 or more people and is located within 15 miles of 

the project dam. 




Chanceford Township 

51 Muddy Creek Forks Rd 

Brogue, PA 17309 

East Lampeter Township 

2250 Old Philadelphia Pike 

Lancaster, PA 17602 

Lower Windsor Township 

2425 Craley Road 

Wrightsville, PA 17368 

Millersville Borough 

100 Municipal Drive 

Millersville, PA 17551 

Oxford Borough 

401 Market Street 

Oxford PA 19363

(3) 



East Nottingham Township 

158 Election Road 

Oxford, PA 19363 

Fulton Township 

777 Nottingham Rd 

Peach Bottom, PA 17563 

City of Lancaster 

120 N Duke St 


Lower Oxford Township 

220 Township Road 

Oxford, PA 19363 

iv 

Paradise Township 

12 Township Dr. 

Paradise PA 17562 

Providence Township 

200 Mt. Airy Road 

New Providence, PA 17560 

West Lampeter Township 

852 Village Road, 

Lampeter, PA 17537 

(iii) Every irrigation district, drainage district or similar special purpose political 

subdivision (A) in which any part of the project is located, and any Federal facility 

that is or is proposed to be used by the project is located, or (B) that owns, operates, 

maintains, or uses any project facility or any Federal facility that is or is proposed to 

be used by the project: 

There is no irrigation district, drainage district, or similar special purpose political 

subdivision in which any part of the project is located or that owns, operates, maintains, 

or uses any project facility. The project uses no Federal facilities and occupies no Federal 

lands. 

(iv) Every other political subdivision in the general area of the Project that there is 

reason to believe would likely be interested in, or affected by, the application. 

There are no other political subdivisions in the general area of the Project that would 

likely be interested in, or affected by, the notification. 

(v) All Indian tribes that may be affected by the Project. 

Delaware Nation 

P.O. Box 825 

Anadarko, OK 73005 

(i) For a license (other than a license under section 15 of the Federal Power Act) state 

that the Applicant has made a good faith effort to give notification by certified mail 

of the filing of the application to: 

(A) Every property owner of record of any interest in the property within the 

bounds of the Project, or in the case of the Project without a specific 

boundary, each such owner of property which would underlie or be adjacent 

to any Project works, including any impoundments; and



(B) The entities identified in paragraph (2) above, as well as any other federal, 

state, municipal or other local government agencies that there is reason to 

believe would likely be interested in or affected by the application. 

PURPA Benefits 

Because Exelon is seeking a new license under section 15 of the Federal Power 

Act, this requirement does not apply. However, Exelon is notifying resource 

agencies, stakeholders, and members of the public consulted through the 

integrated licensing process of the filing of this License Application as required 

by section 5.17(d)(1) of the Commission’s regulations. 

Exelon is not seeking any PURPA benefits in association with the relicensing of the Project. 

v


ACRONYMS AND ABBREVIATIONS 


ACHP Advisory Council on Historic Preservation 

ADA Americans with Disabilities Act 

ADAAG Accessibility Guidelines for Buildings and Facilities 

APE Area of Potential Effect 

BEMP Bald Eagle Management Plan 

BTMP Bog Turtle Management Plan 

CEQ Council of Environmental Quality 

CFR Code of Federal Regulations 

CU Consumptive Use 

CWA Clean Water Act 

cfs Cubic Feet per Second 

dBA Decibel 

°C Degrees Centigrade 

°F Degrees Fahrenheit 

DO Dissolved Oxygen 

DLA Draft License Application 

EA Environmental Assessment 

EIS Environmental Impact Statement 

ESA Endangered Species Act 

Exelon Exelon Generation Company, LLC 

FERC Federal Energy Regulatory Commission 

FLA Final License Application 

FPA Federal Power Act 

FPC Federal Power Commission 

fps Feet Per Second 

ft Feet 

HPMP Historic Properties Management Plan 

IBA Important Bird Area 

ILP Integrated Licensing Process 

IVM Integrated Vegetation Management 

kg Kilogram 

vii



kV Kilovolts 

kVA Kilovolt-Ampere 

MAAC Mid-Atlantic Area Council 

MDNR Maryland Department of Natural Resources 

MGD Millions Gallons per Day 

mg/L Milligrams Per Liter 

MW Megawatt 

MWh Megawatt-Hour 

NAI Natural Areas Inventory 

NEPA National Environmental Policy Act of 1969 

NERC North American Electric Reliability Council 

NGVD 1929 National Geodetic Vertical Datum of 1929 

NHPA National Historic Preservation Act 

NGO Non-Governmental Organization 

NID National Inventory of Dams 

NMFS National Marine Fisheries Service 

NPDES National Pollution Discharge Elimination System 

NRCS Natural Resources Conservation Service 

NRHP National Register of Historic Places 

NOI Notice of Intent 

NTU Nephelometric Turbidity Unit 

NWI National Wetland Inventory 

PAD Pre-Application Document 

PADEP Pennsylvania Department of Environmental Protection 

PADCNR Pennsylvania Department of Conservation and Natural Resources 

PBAPS Peach Bottom Atomic Power Station 

PECO PECO Energy Company 

PEPCo PECO Energy Power Company 

PFBC Pennsylvania Fish and Boat Commission 

PGC Pennsylvania Game Commission 

PGS Pennsylvania Geological Survey 

pH The measure of the acidity or alkalinity of a substance or liquid 

PHMC Pennsylvania Historical and Museum Commission 

viii



PJM Pennsylvania, New Jersey, Maryland Interconnection 

PM&E Protection, Mitigation and Enhancement 

PSP Proposed Study Plan 

REA Ready for Environmental Analysis 

RM River Mile 

RMP Recreation Management Plan 

RSP Revised Study Plan 

ROW Right of Way 

SD1 FERC Scoping Document 1 

SD2 FERC Scoping Document 2 

SHPO Pennsylvania State Historic Preservation Officer 

SMP Shoreline Management Plan 

SRAFRC Susquehanna River Anadromous Fish Restoration Committee 

SRBC Susquehanna River Basin Commission 

SSURGO Soil Survey Geographic Database 

TL Total Length 

TMDL Total Maximum Daily Loads 

TSF Trout Stocking 

USACE United States Army Corps of Engineers 

USDA United States Department of Agriculture 

USDOI United States Department of the Interior 

USEPA United States Environmental Protection Agency 

USFWS United States Fish and Wildlife Service 

USGS United States Geological Survey 

WMA Wildlife Management Area 

WQMAR 2010 Pennsylvania Integrated Water Quality Monitoring and Assessment Report 

WWF Warm Water Fishes 

WY Water Year 

ix


APPLICATION FOR NEW LICENSE 

EXHIBIT A-PROJECT DESCRIPTION


EXHIBIT A-PROJECT DESCRIPTION 

TABLE OF CONTENTS 

Section 1.0 Project Structures ........................................................................................................... 2 

1.1 Main Dam Embankment ................................................................................................................ 2 

1.2 East Dike ........................................................................................................................................ 3 

1.3 Recreation Pond Dam and Spillway .............................................................................................. 3 

1.4 Canal Embankment ........................................................................................................................ 4 

1.5 Upper Reservoir Spillway .............................................................................................................. 4 

1.6 Intake Structure .............................................................................................................................. 4 

1.7 Powerhouse .................................................................................................................................... 5 

Section 2.0 Surface Area, Elevation and Storage Capacity ............................................................ 5 

2.1 Muddy Run Power Reservoir ........................................................................................................ 5 

2.2 Muddy Run Recreation Pond ......................................................................................................... 5 

2.3 Lower Reservoir (Conowingo Pond) ............................................................................................. 5 

Section 3.0 Turbines and Generators ............................................................................................... 6 

Section 4.0 Transmission Lines ......................................................................................................... 6 

Section 5.0 Additional Equipment .................................................................................................... 6 

Section 6.0 Lands of the United States .............................................................................................. 6 

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LIST OF TABLES 

Table 1.6-1: Turbine Intake Structure and Tailrace (Conowingo Pond) Characteristics ................... 7 

Table 3-1: Turbine Unit Characteristics ................................................................................................... 8 

LIST OF FIGURES 

Figure 1-1: Muddy Run Project Structures ............................................................................................. 9 

Figure 1.5-1: Muddy Run Upper Reservoir Spillway Rating Curve .................................................... 10 

A-ii



EXHIBIT A – PROJECT DESCRIPTION 

The following excerpt from the Code of Federal Regulations (CFR) at 18 CFR § 4.51(b) describes the 

required content of this Exhibit. 

Exhibit A is a description of the project. This exhibit need not include information on project works 

maintained and operated by the U.S. Army Corps of Engineers, the Bureau of Reclamation, or any other 

department or agency of the United States, except for any project works that are proposed to be altered 

or modified. If the project includes more than one dam with associated facilities, each dam and the 

associated component parts must be described together as a discrete development. The description for 

each development must contain: 

(1) The physical composition, dimensions, and general configuration of any dams, spillways, penstocks, 

powerhouses, tailraces, or other structures, whether existing or proposed, to be included as part of the 

project; 

(2) The normal maximum surface area and normal maximum surface elevation (mean sea level), gross 

storage capacity, and usable storage capacity of any impoundments to be included as part of the project; 

(3) The number, type, and rated capacity of any turbines or generators, whether existing or proposed, to 

be included as part of the project; 

(4) The number, length, voltage, and interconnections of any primary transmission lines, whether existing 

or proposed, to be included as part of the project (see 16 U.S.C. 796(11)); 

(5) The specifications of any additional mechanical, electrical, and transmission equipment appurtenant 

to the project; and 

(6) All lands of the United States that are enclosed within the project boundary described under 

paragraph (h) of this section (Exhibit G), identified and tabulated by legal subdivisions of a public land 

survey of the affected area or, in the absence of a public land survey, by the best available legal 

description. The tabulation must show the total acreage of the lands of the United States within the 

project boundary.) 

A-1

SECTION 1.0 



PROJECT STRUCTURES 

The Muddy Run Power Project (Muddy Run Project or Project) is a pumped-storage hydroelectric 

generating facility located approximately 22 miles upstream of the Chesapeake Bay on the eastern 

shoreline of the Susquehanna River, within Drumore and Martic Townships, Lancaster County, 

Pennsylvania. 

The Project (Figure 1-1) consists of: 1) a main dam embankment, 2) the east dike, 3) recreation pond dam 

and spillway 4) canal dam embankment, 5) upper reservoir spillway 6), intake structure 7) a powerhouse 

and 8) primary transmission line. 

The recreation pond’s sole purpose is for environmental mitigation and recreation, and its water levels are 

not affected by fluctuations within the Power Reservoir. The recreation pond impoundment level is 

maintained by an uncontrolled open channel spillway. 

1.1. Main Dam Embankment 

Muddy Run Reservoir was created by building a rock-filled dam with a central impervious core across the 

Muddy Run ravine, approximately 2,500 feet from the Muddy Run Powerhouse. The Muddy Run Main 

Dam Embankment (Main Dam) (National Inventory of Dams (NID) PA00266) is 4,800 feet long, has a 

maximum height of 260 feet, and has upstream and downstream slopes of 2.5H:1V and 2.2H:1V, 

respectively. The downstream slope includes a 20-foot wide bench/road at midslope across the highest 

section of the dam. The top few feet of the embankment (above the maximum normal reservoir level) are 

constructed with upstream and downstream slopes of 1.5H: 1V. 

The crest of the dam is at elevation 533 feet, is 34 feet wide and is traversed by a 20-foot-wide two-laned 

roadway (River Road). The crest provides 13 feet of freeboard when the Muddy Run Reservoir water 

level is at elevation 520 feet. 

The Main Dam embankment is constructed as a “zoned” embankment with an impervious core. The 

structure includes two filter zones on each side of the core and upstream and downstream rockfill shells. 

The rockfill consists of excavated schist bedrock. Less weathered rockfill was placed on the downstream 

slope and upper parts of the upstream shell. More weathered rockfill was placed in the downstream shell 

and lower parts of the upstream shell under a 20-foot-thick “fresh rock” cover. The downstream shell also 

includes a zone of 10-foot-thick random material layers alternating with 3-foot-thick layers of weathered 

rock. 

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The core is centrally located and symmetrical, 20 feet wide at the top and increasing by 0.6 feet with each 

foot of depth. The core is constructed of silty soil which is the product of extreme weathering of the 

schists close to the ground surface. The core is carried in a trench down to hard fresh rock in the gorge of 

Muddy Run, to firm weathered rock between elevations 370 and 470, and to a depth of 10 feet where the 

ground surface is above elevation 470. A grout curtain was installed by advancing drill holes (3 rows of 

drill holes below El. 470 and 1 row below El. 470) from which the grouting was completed in stages. In 

addition to vertical drill holes, inclined drill holes were used in order to better intersect a steeply dipping 

system of bedrock joints. 

Drainage of the downstream shell, downstream filter and foundation rock is provided by longitudinal 

drains beneath the downstream shell. Eleven relief wells are installed at the toe of the embankment in the 

gorge, and seven wells are installed on the north abutment. 

1.2. East Dike 

The East Dike (NID PA83010) is approximately 800 feet long, has a crest width of 20 feet, has a 

maximum height of about 12 feet and has upstream and downstream slopes of 2.5H:1V and 2.2H:1V, 

respectively. The east dike is also a zoned earth and rock-fill embankment with an impervious core. The 

crest of the east dike has an elevation of 530.8 feet. 

1.3. Recreation Pond Dam and Spillway 

The Recreation Pond Dam (NID PA83009), located in the drainage for the upper reservoir about two 

miles upstream of the Main Dam, is a zoned earth and rockfill embankment. The dam is approximately 

750 feet long, has a maximum height of about 90 feet and a crest width of 34 feet. 

Both slopes of the recreation dam are 2.5H: 1V. The crest is at elevation 530. The top three feet of the 

embankment (above the maximum normal reservoir level) is constructed with upstream and downstream 

slopes of 1.5H: 1V. The dam includes a 4-foot diameter concrete outlet pipe located in an excavated rock 

trench at the base of the dam. The outlet is controlled from the upstream end by a flap gate. The portion 

of the trench located under the impervious core of the dam has been backfilled with concrete after 

installation of the outlet pipe. 

The recreation pond spillway consists of a nearly level rock cut channel approximately 140 feet wide with 

a concrete weir at crest elevation 520 feet. The spillway is traversed by a steel and concrete bridge which 

is used by pedestrian traffic and by recreation area maintenance vehicles. 

A-3



1.4. Canal Embankment 

The Canal Embankment (NID PA83008), or the Muddy Run Intake Channel Dam, forms the upper part 

of the intake channel which leads from the upper reservoir to the intake structure. The lower part of the 

channel is excavated in rock. The embankment has a maximum height of about 35 feet, side slopes of 

1.5H: 1V and a minimum crest width of 25 feet. The upstream face of the embankment and the rock cut 

channel are lined with a nine-inch-thick reinforced concrete slab extending about 1,000 feet upstream on 

both sides of the canal from the cylinder gates. The upstream portion of the canal is an unlined soil and 

rock cut. River Road Bridge crosses this section of the canal. 

1.5. Upper Reservoir Spillway 

The spillway for the upper reservoir is located on the west side of the intake canal. It is a concrete ogee 

type structure 200 feet long, 20 feet high, has a crest elevation of 521 feet and discharges into a vegetated 

natural ravine. A rating curve for this structure is depicted in Figure 1.5-1. The spillway is constructed 

within the canal dike and is flanked by concrete retaining walls. Discharges over the spillway would 

follow the natural ravine which joins Muddy Run Creek just above its confluence with the Susquehanna 

River. 

The purpose of the spillway is to protect the embankments from overtopping in the event of inadvertent 

over-pumping or in the case of a flood which could not be passed through the generating units. Since 

initial filling of the upper reservoir in 1967, the spillway has never been required to pass discharges from 

either natural inflows or over-pumping. 

1.6. Intake Structure 

The Intake Structure which admits water for power generation consists of four cylinder gates with trash 

racks (clear spacing of 5.375 inches) (Table 1.6-1). Each intake supplies two units and includes a 

cylindrical tower which leads to a 430-foot-deep vertical shaft. The vertical shafts and horizontal power 

tunnels are concrete lined with a diameter of 24.5 feet. The concrete lined power tunnels bifurcate 

approximately 500 feet upstream of the powerhouse. Beginning approximately 400 feet upstream of the 

powerhouse, the tunnels transition to 14-foot-diameter steel penstocks that continue downstream to 

connect to one of eight pump turbine units in the powerhouse. There are no inlet valves at the 

downstream end of the penstocks. 

A-4

1.7. Powerhouse 



The Muddy Run powerhouse has dimensions of approximately 600 feet long by 133 feet wide, and is 

constructed entirely of concrete. A gantry crane travels the length of the powerhouse and service bay. 

The powerhouse is a semi-outdoor structure located on the east bank of the Susquehanna River and 

contains eight vertical shaft reversible pump generating units with a total nameplate capacity of 800 1 MW 

(at 0.9 power factor). 

SECTION 2.0 

SURFACE AREA, ELEVATION AND STORAGE CAPACITY 

2.1. Muddy Run Power Reservoir 

The Muddy Run Power Reservoir’s normal operating elevation ranges from 470 feet to 520 feet. At 

elevation 520 feet, the Power Reservoir has a total storage capacity of 56,731 acre-feet with a usable 

capacity of 33,894 acre-feet, and a surface area of 892 acres. At the maximum drawdown elevation (470 

feet), the Power Reservoir has a surface area of 471 acres. 

2.2. Muddy Run Recreation Pond 

The Muddy Run Recreation Pond has a total storage capacity of 709 acre-feet, and is maintained at a 

constant elevation of 520 feet for recreational purposes. The surface area of the Recreation Pond is 

approximately 100 acres at elevation 520 feet. 

2.3. Lower Reservoir (Conowingo Pond) 

The lower reservoir for the Muddy Run Project is Conowingo Pond, which is a portion of the 

Susquehanna River that is impounded by Conowingo Dam. 

The lower reservoir (Conowingo Pond) has a total surface area of approximately 8,500 acres and a design 

storage volume of approximately 310,000 acre-feet at the maximum normal level of 109.2 feet, of which 

71,000 acre-feet are usable storage.. The current Conowingo Project license allows the lower reservoir to 

1 The rated generation capacity for the Muddy Run Powerhouse is 800 MW, which is based on the 

nameplate capacity of the 8 turbine/generator units combined. However, actual generation capacity 

can vary based upon hydraulic head and turbine/generator efficiency. The Project can achieve 1070 

MW under ideal operating conditions, which also represents the Project’s Installed Capacity (ICAP) 

based on the PJM ICAP definition. 

A-5



normally fluctuate between elevation 101.2 and 110.2 feet; however, the lower reservoir is normally kept 

above elevation 104.7 feet. 

SECTION 3.0 

TURBINES AND GENERATORS 

Muddy Run contains eight Francis-type pump-turbine/motor-generator units (Table 3-1). The 

powerhouse turbines each have a hydraulic capacity of 4,000 cfs at a rated head of 412 feet, for a total 

discharge capacity from the powerhouse of 32,000 cfs. The pumping capacity of the pump turbines is 

3,500 cfs each at a rated head of 427 feet, for a total powerhouse pumping capability of 28,000 cfs. The 

draft tubes discharge directly to the Susquehanna River adjacent to the powerhouse. The units are 

equipped with trash racks (clear spacing of 5.75 inches) between the draft tube outlet and the river. 

The electrical generating equipment consists of eight motor-generator units, each rated at 13.8 kilovolts 

(kV), 3 phase, 60 cycle, 100 MW at 0.9 power factor at a temperature rise of 140�F (60�C) as a generator. 

Switching and control equipment are connected to the eight motor-generators in pairs to the four 13.8-220 

kV transformers. A 13.8 kV circuit breaker is provided on each motor-generator. 

SECTION 4.0 

TRANSMISSION LINES 

The primary transmission lines within the Project boundary consist of two 230 kV three-phase, three-wire 

circuits. The lines, owned by Exelon, but leased to the PECO Energy Company, an affiliate of Exelon, 

are identified as Line 220-06 and 220-07. Both lines begin at a 220 kV switching station located on the 

roof of the Muddy Run Powerhouse and run approximately 4.25 miles to the Peach Bottom Atomic 

Power Station (PBAPS) North Substation located in York County. Each line has a 230 kV nominal 

phase-to-phase voltage and has a normal and emergency rating of 598,000 Kilovolt-Amperes (kVA). 

Both lines exist in a common 300 foot wide right-of-way, with some variations at the Susquehanna River 

crossing. 

SECTION 5.0 

ADDITIONAL EQUIPMENT 

The Muddy Run Project also includes various turbine governors, generator exciters, batteries, control 

panels, and circuit breakers. 

SECTION 6.0 

LANDS OF THE UNITED STATES 

No lands of the United States are enclosed within the Project Boundary. 

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TABLE 1.6-1: TURBINE INTAKE STRUCTURE AND TAILRACE (CONOWINGO POND) 

CHARACTERISTICS 

Site Characteristic 

Muddy Run Power 

Reservoir 

A-7 

Conowingo Pond 

Surface Area-Full Pond (acres) 892 8,500 

Maximum / Mean Reservoir Depth at 

Normal Full Pond (ft) 

220 / 60 100 / 20 

Normal Full Pond Elevation (ft, NGVD 29) 520.0 109.2 

Minimum Pond Elevation (ft, NGVD 29) 470.0 101.2 

Maximum Pond Elevation (ft, NGVD 29) 520.0 110.2 

Intake 

Elevations 

Unit Intake Width (ft) 

Unit Screened Area (sq ft) 

Trash Rack 

Bars 

Top (ft, NGVD 29) 455.0 71.4 

CL (ft, NGVD 29) 447.5 66.7 

Bottom (ft, NGVD 29) 440.0 61.9 

12.1 per bay, 

6 bays per unit 

181.5 per bay, 


15.8 per bay, 


834.8 per bay, 


Thickness (in) 0.625 1.9 

Height (in) 15 15 

Clear Spacing (in) 5.375 5.5 

Approach Velocity in front of Trashrack 

(fps) 

3.67 4.19 

Turbine Unit Operating 1 through 8 1 through 8

Turbine Type 



Turbine 

Characteristics 

TABLE 3-1: TURBINE UNIT CHARACTERISTICS 

A-8 

Generating Pumping 

Reversible Francis 

(No’s. 1 through 8) 

Nameplate Turbine Capacity (MW) 100 

Rated Hydraulic Capacity (cfs) 4,000 3,500 

Design Head (ft) 

Runner Diameter (ft) 

412 427 

Inlet 17.45 11.9 

Outlet 11.9 17.45 

Runner Speed (rpm) 180 

Number of Buckets 7 

Bucket (blade) Tip Speed (ft/sec) 164.5 

No. of Wicket Gates 20 

Wicket Gate Spacing (in) 16.6 

Pad Height (in) - clear distance between 

top and bottom of wicket gate 

36

Discharge (cfs) 

18,000 

16,000 

14,000 

12,000 

10,000 

8,000 

6,000 

4,000 

2,000 

0 



FIGURE 1.5-1: MUDDY RUN UPPER RESERVOIR SPILLWAY RATING CURVE 

Q=3.85*200*(Pond Elevation-521) 3/2 

520 521 522 523 524 525 526 527 528 529 530 

Reservoir Level (ft) 

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EXHIBIT B-PROJECT OPERATION AND RESOURCE UTILIZATION

Section 1.0 


EXHIBIT B-PROJECT OPERATION AND RESOURCE UTILIZATION 


Existing And Proposed Project Operation ................................................................... 2 

1.1 Existing Project Operation ............................................................................................................. 2 

1.2 Proposed Project Operation ........................................................................................................... 2 

1.3 Annual Plant Factor ....................................................................................................................... 2 

1.4 Operation During Adverse, Mean and High Water Years ............................................................. 2 

1.5 Lower Susquehanna River Operations Model ............................................................................... 3 

Section 2.0 

Dependable Capacity and Average Annual Generation .............................................. 4 

2.1 Estimate of Dependable Capacity and Average Annual Generation ............................................. 4 

2.2 Streamflow ..................................................................................................................................... 4 

2.3 Area-Capacity Curve ..................................................................................................................... 5 

2.4 Hydraulic Capacity ........................................................................................................................ 5 

2.5 Tailwater Rating Curve .................................................................................................................. 5 

2.6 Powerplant Capability versus Head Curve .................................................................................... 5 

Section 3.0 

Section 4.0 

Utilization of Project Power ........................................................................................... 6 

Plans for Future Development ....................................................................................... 6 

B-i




Table 2.1-1: Monthly and Annual Net Generation (MWh) for 1996-2010 ............................................ 7 

Table 2.1-2: Monthly and Annual Net Energy Use During Pumping (MWh) for 1996-2010. ............. 8 

Table 2.2-1: Conowingo Average and Median Flow By Month, Computed From Daily Average 

Flow Records (WY 1968-2009) .......................................................................................................... 9 

Table 2.2-2: Conowingo Annual and Monthly Daily Average Flow Exceedence Percentiles, in cfs 

(WY 1968-2009). ................................................................................................................................ 10 

Table 2.2-3: Average Monthly Withdrawal and Discharge (2006-2010) ............................................. 11 

Table 2.3-1: Muddy Run Power Reservoir Storage and Surface Area Curve. ................................... 12 

B-ii




Figure 2.2-1: January Monthly Flow Duration Curve. Source: WY 1968-2009 daily average flow 

data. .................................................................................................................................................... 13 

Figure 2.2-2: February Monthly Flow Duration Curve. Source: WY 1968-2009 daily average flow 

data. .................................................................................................................................................... 14 

Figure 2.2-3: March Monthly Flow Duration Curve. Source: WY 1968-2009 daily average flow 

data. .................................................................................................................................................... 15 

Figure 2.2-4: April Monthly Flow Duration Curve. Source: WY 1968-2009 daily average flow data. 

............................................................................................................................................................ 16 

Figure 2.2-5: May Monthly Flow Duration Curve. Source: WY 1968-2009 daily average flow data. 

............................................................................................................................................................ 17 

Figure 2.2-6: June Monthly Flow Duration Curve. Source: WY 1968-2009 daily average flow data. 

............................................................................................................................................................ 18 

Figure 2.2-7: July Monthly Flow Duration Curve. Source: WY 1968-2009 daily average flow data. 

............................................................................................................................................................ 19 

Figure 2.2-8: August Monthly Flow Duration Curve. Source: WY 1968-2009 daily average flow 

data. .................................................................................................................................................... 20 

Figure 2.2-9: September Monthly Flow Duration Curve. Source: WY 1968-2009 daily average flow 

data. .................................................................................................................................................... 21 

Figure 2.2-10: October Monthly Flow Duration Curve. Source: WY 1968-2009 daily average flow 

data. .................................................................................................................................................... 22 

Figure 2.2-11: November Monthly Flow Duration Curve. Source: WY 1968-2009 daily average flow 

data. .................................................................................................................................................... 23 

Figure 2.2-12: December Monthly Flow Duration Curve. Source: WY 1968-2009 daily average flow 

data. .................................................................................................................................................... 24 

Figure 2.3-1: Muddy Run Power Reservoir Storage and Surface Area Curve ................................... 25 

Figure 2.6-1: Gross Head vs. Unit Output .............................................................................................. 26 

B-iii



EXHIBIT B – PROJECT OPERATION AND RESOURCE UTILIZATION 

The following excerpt from the Code of Federal Regulations (CFR) at 18 CFR § 4.51 (c) describes the 


Exhibit B is a statement of project operation and resource utilization. If the project includes more than 

one dam with associated facilities, the information must be provided separately for each such discrete 

development. The exhibit must contain: 

(1) A statement whether operation of the powerplant will be manual or automatic, an estimate of the 

annual plant factor, and a statement of how the project will be operated during adverse, mean, and high 

water years; 

(2) An estimate of the dependable capacity and average annual energy production in kilowatt hours (or a 

mechanical equivalent), supported by the following data: 

(i) The minimum, mean, and maximum recorded flows in cubic feet per second of the stream or other 

body of water at the powerplant intake or point of diversion, with a specification of any adjustments 

made for evaporation, leakage, minimum flow releases (including duration of releases), or other 

reductions in available flow; monthly flow duration curves indicating the period of record and the 

gauging stations used in deriving the curves; and a specification of the period of critical streamflow 

used to determine the dependable capacity; 

(ii) An area-capacity curve showing the gross storage capacity and usable storage capacity of the 

impoundment, with a rule curve showing the proposed operation of the impoundment and how the 

usable storage capacity is to be utilized; 

(iii) The estimated hydraulic capacity of the powerplant (minimum and maximum flow through the 

powerplant) in cubic feet per second; 

(iv) A tailwater rating curve; and 

(v) A curve showing powerplant capability versus head and specifying maximum, normal, and 

minimum heads; 

(3) A statement, with load curves and tabular data, if necessary, of the manner in which the power 

generated at the project is to be utilized, including the amount of power to be used on-site, if any, the 

amount of power to be sold, and the identity of any proposed purchasers; and 

(4) A statement of the applicant's plans, if any, for future development of the project or of any other 

existing or proposed water power project on the stream or other body of water, indicating the 

approximate location and estimated installed capacity of the proposed developments. 

B-1

SECTION 1.0 



EXISTING AND PROPOSED PROJECT OPERATION 

1.1 Existing Project Operation 

The Muddy Run Project is a pumped storage hydroelectric facility. Water is pumped from the lower 

reservoir (Conowingo Pond) to the upper reservoir which has 33,894 acre-feet of active storage available 

for pump storage operations. Typically, pumping occurs during low-load periods when energy costs are 

low, while generation occurs during high-load periods. 

The Muddy Run Project is typically operated from control panels at the Muddy Run powerhouse. The 

Project, however, has automatic generation control equipment capable of starting, running and stopping 

the units and their auxiliaries. This equipment permits remote operation of the plant in generation mode 

from the corporate office in Kennett Square, Pennsylvania. 

1.2 Proposed Project Operation 

Exelon is not proposing any changes to Project operations. 

1.3 Annual Plant Factor 

The average annual plant factor is determined using the following equation: 

Average Annual Output/Nameplate Capacity x 8,760 hrs per yr= Avg. Annual Plant Factor 

For the 1996 to 2010 period, the Project has an average annual generation of 1,615,813 MWh per year 

and an average annual energy consumption of approximately 2,090,726 MWh per year. The Project’s 

annual plant factor is approximately 23% based on its current nameplate capacity of 800 MW. 

1.4 Operation During Adverse, Mean and High Water Years 

Operation of the Muddy Run Project is not generally impacted by changes in the hydrologic conditions 

when compared to conventional hydroelectric projects. Pumped-storage projects are considered to be 

closed systems, in that they maintain a usable volume of water that is cycled between the upper and lower 

reservoirs without the need to store or use water flowing through the Project from the upper reaches of the 

drainage basin. Given this, the operation of the Muddy Run Project depends upon maintaining a specific 

total usable volume of water between the Muddy Run Power Reservoir and Conowingo Pond, to limit 

impacts to the power production. 

B-2



During mean flow years, flow issues do not typically arise at the Project, as there are sufficient flows to 

maintain the total usable volume of water for Project operations and to provide flows downstream of 

Conowingo Dam. During a high-flow year, the Project will also have sufficient water available to 

maintain the total usable volume in the system, while also passing higher levels of flow downstream. 

However, during extreme high-flow events, Project operations could be impacted by having excess water 

in the system. Exelon typically adjusts operations to reduce the levels in the upper reservoir prior to high 

Susquehanna River flow conditions. This allows the upper reservoir to be re-filled during high flow 

periods and possibly reduce spill conditions at Conowingo Dam. Extended periods of high flow 

conditions (potential spill situation at Conowingo Dam) could reduce the generation at the Muddy Run 

Project when Conowingo Pond is at or near full pond conditions, in order to reduce spill over the 

Conowingo Dam. 

During adverse water years, with limited inflow, the water management for the Project will require 

adjustments in the generation cycle. The most typical occurrence is a reduction in the total usable volume 

of water available for Project operations. The extent of the adjustments in flow and the volume of water 

retained in the Muddy Run Power Reservoir and Conowingo Pond will depend upon the level of low flow 

experienced, as well as the length of time of the adverse low-flow conditions. Maintaining the licensed 

Conowingo Pond levels and minimum flow requirements below Conowingo Dam are the primary factors 

affecting the total usable volume of water. 

1.5 Lower Susquehanna River Operations Model 

Exelon developed an operations model to better understand how operational changes at the lower 

Susquehanna River’s four hydroelectric facilities (Safe Harbor, Holtwood, Muddy Run, and Conowingo) 

affect the timing of river flows and energy generation. The model takes into account each Project’s 

engineering data and operational constraints, such as Conowingo’s minimum flow requirements. The 

model outputs include hourly flow, pond elevations, and generation from the lower Susquehanna River’s 

four hydroelectric projects. 

The model calibration procedure involved adjusting several model parameters and constraints to match 

historic (2004-2007) Project data (flow, stage, generation), and then using the parameters and constraints 

from the final calibrated model to predict Project operations over a longer-term period (1930-2007) to 

establish a “Baseline” model. 

B-3



The Baseline model results showed that from calendar year 1930 through 2007 the average annual 

generation at Muddy Run was 1,739,000 MWh generated, while 2,261,000 MWh was used for Muddy 

Run pumping operations. 

Some sections of this license application, including Exhibit D and Exhibit E-Developmental Analysis, 

utilize the Baseline model outputs. Sections using model outputs will explicitly state when model results 

(as opposed to actual data) are presented. 

SECTION 2.0 

DEPENDABLE CAPACITY AND AVERAGE ANNUAL GENERATION 

2.1 Estimate of Dependable Capacity and Average Annual Generation 

The net dependable capacity of the Muddy Run Project is 1,070 MW 2 . 

Average annual net generation at the Project for the 1996-2010 period was 1,615,813 MWh. Average 

annual pumping generation use by the Project for the same time period was 2,090,726 MWh. The 

monthly and annual net generation and pumping energy use at the Project for the 1996-2010 period is 

provided in Table 2.1-1 and Table 2.1-2 respectively. 

2.2 Streamflow 

The Conowingo USGS gage (Station 01578310), located on the downstream face of Conowingo Dam in 

the Susquehanna River, measures the discharge from Conowingo Dam. Conowingo Dam outflows 

reflects the combined influences of the Conowingo Hydroelectric Project, the Muddy Run Project, 

Holtwood Hydroelectric Project, Safe Harbor Hydroelectric Project and all other upstream water users 

along the Susquehanna River. 

The Susquehanna River at the Conowingo gage drains a 27,100 square mile watershed. Between water 

year 3 1968 and 2009 Conowingo had an annual average flow of 41,026 cfs. Monthly average and median 

flows are greatest in March and April and lowest in August and September (Table 2.2-1). Table 2.2-2 

2 This figure represents Muddy Run’s Installed Capacity (ICAP) (Winter/Summer) based on the following PJM 

ICAP definition: Value based on the summer net dependable rating of the unit as determined in accordance with 

PJM’s Rules and Procedures of the Determination of Generating Capacity (Manual 21). 

3 Water years refer to a year that begins in October and ends in September. For example, water year 1968 begins on 

10/1/1967 and ends on 9/30/1968. 

B-4



shows annual and monthly flow duration curves calculated from daily average) flow data. Figures 2.2-1 

thru 2.2-12 show monthly flow duration curves from daily average flow data graphically. 

Station operational records were used to estimate the Muddy Run Project’s average monthly withdrawals 

and discharges for the period 2006-2010 (Table 2.2-3). 

2.3 Area-Capacity Curve 

Storage and surface area curves for the Muddy Run Power Reservoir are shown in Table 2.3-1. The 

storage and surface area curves for the Muddy Run Power Reservoir are also plotted in Figure 2.3-1. The 

Power Reservoir’s normal operating range is between 470 ft and 520 ft, which provides a total usable 

storage of 33,894 acre-feet. 

2.4 Hydraulic Capacity 

The hydraulic capacity of each of the reversible pump units in the pumping mode is approximately 3,500 

cfs at a rated head of 427 feet. The hydraulic capacity of each of the units in the generation mode is 

approximately 4,000 cfs at a rated head of 412 feet. Therefore, the Project’s total maximum rated 

pumping and generating hydraulic capacities are 28,000 cfs and 32,000 cfs, respectively, at a rated head 

of 412 feet. 

2.5 Tailwater Rating Curve 

The Muddy Project Run uses Conowingo Pond as a lower reservoir. Conowingo Pond elevations reflect 

multiple influences, including operations at the Muddy Run Pumped Storage Project, the Holtwood 

Hydroelectric Project and the Conowingo Hydroelectric Project. Therefore, Muddy Run’s hour-to-hour 

operations do not necessarily correlate with Conowingo Pond elevations, such that a traditional tailwater 

elevation versus plant discharge relationship can be produced. However, Conowingo Pond is typically 

maintained between elevations 104.7 feet and 109.2 feet, though elevations can rise above or below that 

elevation range during extreme flow events. 

2.6 Powerplant Capability versus Head Curve 

A curve illustrating the maximum generating capacity available at a given gross head (headwater 

elevation minus tailwater elevation) is provided in Figure 2.6-1. The maximum, normal, and minimum 

heads at the Project are 419 feet, 390 feet, and 360 feet, respectively. 

B-5

SECTION 3.0 



UTILIZATION OF PROJECT POWER 

The primary purpose of the Project is to supply energy, capacity, regulation and other ancillary services to 

the PJM Interconnection, a regional transmission organization that coordinates the movement of 

wholesale electricity in all or parts of Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New 

Jersey, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, and the District of 

Columbia. The Project typically pumps water to the Upper Reservoir during the night, when power 

demand is low, which provides base load to the system and energy storage for the following day’s 

generation. 

SECTION 4.0 

There are no plans for future development. 

PLANS FOR FUTURE DEVELOPMENT 

B-6



TABLE 2.1-1: MONTHLY AND ANNUAL NET GENERATION (MWH) FOR 1996-2010 

Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual 

1996 122,869 111,594 129,055 113,306 129,571 131,806 156,642 149,309 103,803 115,011 98,363 105,946 1,467,275 

1997 96,621 79,897 101,741 106,005 104,610 123,547 144,858 154,176 121,869 129,000 102,744 130,311 1,395,379 

1998 113,592 101,368 82,616 83,737 83,529 140,446 160,522 141,248 134,781 138,034 108,812 130,476 1,419,161 

1999 129,904 114,413 124,032 107,190 92,964 144,434 157,848 149,303 136,136 87,372 113,894 120,290 1,477,780 

2000 122,281 101,686 114,606 90,533 105,099 122,046 140,910 157,131 135,147 107,442 105,065 113,873 1,415,819 

2001 124,666 128,135 134,343 116,836 137,351 155,103 155,481 158,730 140,835 113,726 92,095 141,263 1,598,564 

2002 147,619 116,751 110,991 146,136 155,333 159,937 163,245 72,027 25,627 152,032 155,087 139,689 1,544,474 

2003 157,152 141,148 152,950 127,461 145,522 147,417 165,578 158,846 155,399 170,274 147,039 161,037 1,829,823 

2004 142,215 133,445 137,582 118,204 132,736 151,422 157,608 168,987 144,285 145,147 128,827 152,032 1,712,490 

2005 138,692 131,390 129,011 96,713 152,648 157,848 160,140 150,077 133,731 130,039 159,803 144,561 1,684,653 

2006 142,839 117,513 117,056 107,135 147,070 144,394 173,217 175,814 122,881 166,358 146,246 146,731 1,707,254 

2007 150,238 126,464 147,128 70,440 162,860 156,809 154,261 170,335 163,811 181,178 159,933 169,132 1,812,589 

2008 168,630 155,272 163,539 146,204 172,700 174,720 152,626 142,917 157,299 154,564 133,946 150,266 1,872,683 

2009 136,456 127,273 91,048 144,572 151,558 153,473 162,450 171,407 144,871 144,242 128,880 146,141 1,702,371 

2010 158,216 147,473 104,428 135,319 153,988 158,397 120,045 79,842 151,182 128,132 124,129 135,730 1,596,881 

Average 136,799 122,255 122,675 113,986 135,169 148,120 155,029 146,677 131,444 137,503 126,991 139,165 1,615,813 

B-7



TABLE 2.1-2: MONTHLY AND ANNUAL NET ENERGY USE DURING PUMPING (MWH) FOR 1996-2010. 

Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual 

1996 180,303 163,757 195,449 151,891 186,012 200,304 213,849 213,313 158,362 161,485 148,940 156,125 2,129,790 

1997 134,800 116,934 150,972 148,626 133,727 160,008 203,708 213,836 160,986 170,583 148,801 164,869 1,907,850 

1998 153,589 131,661 108,387 112,226 109,928 182,834 204,452 184,652 171,052 185,763 144,109 166,152 1,854,805 

1999 175,529 146,906 153,721 135,558 125,358 190,300 195,850 200,420 161,095 119,020 143,691 155,519 1,902,967 

2000 162,563 136,253 145,701 124,117 133,510 153,505 180,733 193,601 176,813 138,299 135,815 141,111 1,822,021 

2001 164,391 157,337 176,474 156,169 168,008 194,683 198,199 199,695 189,042 134,328 120,027 184,986 2,043,339 

2002 175,090 149,671 158,876 181,578 200,014 211,819 201,452 90,538 38,015 197,826 199,651 186,873 1,991,403 

2003 198,379 181,258 196,906 155,671 182,413 193,881 205,046 205,543 191,249 208,727 195,217 197,745 2,312,035 

2004 187,172 175,086 176,196 147,827 169,301 188,940 196,274 210,510 183,813 194,255 168,869 189,195 2,187,438 

2005 189,049 167,757 162,464 124,715 199,594 198,104 206,009 187,004 166,426 171,568 193,917 186,950 2,153,557 

2006 180,134 148,990 146,773 145,480 174,276 181,196 221,775 216,143 160,983 211,049 182,972 191,083 2,160,854 

2007 185,505 163,291 193,244 92,554 200,305 195,176 204,315 205,360 212,086 228,601 203,125 220,675 2,304,237 

2008 214,450 193,935 207,730 191,606 213,352 223,554 197,194 174,438 205,146 192,296 173,666 188,804 2,376,171 

2009 176,197 170,337 113,622 183,319 198,632 188,346 203,697 225,801 181,773 187,608 166,811 180,268 2,176,411 

2010 213,198 185,076 133,020 170,424 198,322 193,213 159,688 97,649 188,237 172,457 155,689 171,033 2,038,006 

Average 179,357 159,217 161,302 148,117 172,850 190,391 199,483 187,900 169,672 178,258 165,420 178,759 2,090,726 

B-8



TABLE 2.2-1: CONOWINGO AVERAGE AND MEDIAN FLOW BY MONTH, COMPUTED 

FROM DAILY AVERAGE FLOW RECORDS (WY 1968-2009) 

Month 

Average 

Flow (cfs) 

Median 

Flow (cfs) 

January 45,340 30,250 

February 50,783 36,800 

March 73,846 58,900 

April 76,957 61,800 

May 47,092 39,400 

June 34,894 24,500 

July 20,001 15,700 

August 14,917 10,650 

September 19,109 10,400 

October 23,755 13,800 

November 36,037 28,700 

December 50,533 40,300 

B-9



TABLE 2.2-2: CONOWINGO ANNUAL AND MONTHLY DAILY AVERAGE FLOW EXCEEDENCE PERCENTILES, IN CFS (WY 1968-2009). 

Exceedance 

Percentile 

Annual Jan Feb March April May June July August Sept Oct Nov Dec 

0 1,040,000 556,000 446,000 444,000 431,000 223,000 1,040,000 223,000 199,000 545,000 246,000 265,000 348,000 

5 123,000 130,000 139,700 185,900 182,000 109,000 76,930 48,390 38,775 56,770 81,990 91,615 125,950 

10 86,500 93,990 103,000 140,000 146,100 80,980 55,110 35,080 26,000 32,010 51,460 68,450 96,000 

15 68,400 72,055 80,730 120,000 120,000 67,985 46,415 29,700 20,385 23,100 37,485 57,575 77,670 

20 58,000 59,800 66,680 105,000 104,000 62,480 39,900 25,800 17,600 18,600 29,180 49,120 68,900 

25 49,300 50,675 58,100 92,475 92,700 56,300 35,700 22,700 16,075 16,100 23,250 42,450 60,075 

30 42,800 43,370 50,520 81,240 83,590 51,870 31,930 20,300 14,600 13,830 20,100 38,000 53,400 

35 37,400 38,500 45,280 72,665 76,170 47,100 29,535 18,600 12,965 12,200 17,000 34,435 49,400 

40 33,000 35,000 40,560 67,100 70,040 43,360 26,900 16,760 11,500 10,900 14,900 32,000 44,360 

45 29,100 30,855 36,030 61,500 65,100 40,255 24,390 15,000 10,400 9,489 12,800 28,745 40,800 

50 25,700 27,000 32,200 56,200 60,700 37,000 22,450 13,900 9,570 8,655 11,200 26,250 37,000 

55 22,600 24,300 30,000 50,645 56,055 34,000 20,255 12,745 8,809 7,960 10,245 24,100 34,200 

60 19,800 21,840 27,700 46,700 51,420 32,000 18,760 11,800 8,062 7,426 9,310 21,360 31,100 

65 17,300 19,900 26,000 43,200 47,100 29,270 17,600 10,900 7,520 6,900 8,574 18,800 28,235 

70 15,000 18,000 23,800 39,830 43,300 26,800 16,100 9,986 6,989 6,277 7,913 16,270 25,400 

75 12,700 16,600 21,600 36,300 39,500 24,825 14,400 9,273 6,493 5,790 7,090 13,600 22,800 

80 10,700 15,420 19,000 31,800 35,980 22,420 13,100 8,446 5,892 5,390 6,514 11,400 20,600 

85 8,720 13,800 17,000 27,900 33,000 20,900 12,100 7,618 5,530 4,870 5,940 9,434 18,600 

90 7,050 12,110 15,000 24,210 28,370 18,600 11,000 6,721 5,091 4,429 5,360 7,935 16,110 

95 5,530 9,600 12,030 17,805 23,500 15,205 8,577 5,401 4,361 3,800 4,453 5,809 10,400 

100 2,150 4,200 6,600 9,000 17,500 11,500 4,830 3,710 2,630 2,150 3,570 4,490 5,110 

B-10



TABLE 2.2-3: AVERAGE MONTHLY WITHDRAWAL AND DISCHARGE (2006-2010) 

Month Average Daily Withdrawal (MG) 

Average Daily Discharge 

(MG) 

January 4,529 (4,586) 

February 4,505 (4,506) 

March 3,831 (3,858) 

April 3,890 (3,830) 

May 4,686 (4,782) 

June 4,860 (4,921) 

July 4,747 (4,629) 

August 4,422 (4,511) 

September 4,708 (4,656) 

October 4,732 (4,709) 

November 4,310 (4,350) 

December 4,537 (4,555) 

B-11



TABLE 2.3-1: MUDDY RUN POWER RESERVOIR STORAGE AND SURFACE AREA CURVE. 

Elevation 

(ft) 

Power 

Reservoir 

Storage (MG) 

Power Reservoir 

Storage (acre-ft) 

B-12 

Power Reservoir 

Surface Area 

(acres) 

520 18,487 56,731 892 

515 17,070 52,382 848 

510 15,723 48,250 805 

505 14,447 44,332 762 

500 13,240 40,634 719 

495 12,103 37,140 677 

490 11,035 33,863 633 

485 10,036 30,798 593 

480 9,104 27,936 551 

475 8,241 25,288 509 

470 7,442 22,837 471 

465 6,704 20,573 437 

460 6,017 18,463 407 

455 5,377 16,500 378 

450 4,787 14,689 346 

445 4,248 13,035 316 

440 3,756 11,525 289 

435 3,306 10,145 264 

430 2,895 8,883 241 

425 2,520 7,733 220 

420 2,178 6,684 200 

415 1,868 5,733 180 

410 1,590 4,881 161 

405 1,343 4,121 143 

400 1,122 3,444 127 

395 927 2,843 114 

390 753 2,309 100 

385 601 1,845 87 

380 469 1,439 76 

375 353 1,082 66 

370 251 771 58 

365 165 506 47 

360 96 293 37 

355 48 148 22 

350 20 60 13 

345 5 14 5 

340 1 2 1 

335 0 0 0



FIGURE 2.2-1: JANUARY MONTHLY FLOW DURATION CURVE. SOURCE: WY 1968-2009 

DAILY AVERAGE FLOW DATA. 

B-13



FIGURE 2.2-2: FEBRUARY MONTHLY FLOW DURATION CURVE. SOURCE: WY 1968-2009 


B-14



FIGURE 2.2-3: MARCH MONTHLY FLOW DURATION CURVE. SOURCE: WY 1968-2009 


B-15



FIGURE 2.2-4: APRIL MONTHLY FLOW DURATION CURVE. SOURCE: WY 1968-2009 


B-16



FIGURE 2.2-5: MAY MONTHLY FLOW DURATION CURVE. SOURCE: WY 1968-2009 


B-17



FIGURE 2.2-6: JUNE MONTHLY FLOW DURATION CURVE. SOURCE: WY 1968-2009 


B-18



FIGURE 2.2-7: JULY MONTHLY FLOW DURATION CURVE. SOURCE: WY 1968-2009 


B-19



FIGURE 2.2-8: AUGUST MONTHLY FLOW DURATION CURVE. SOURCE: WY 1968-2009 


B-20



FIGURE 2.2-9: SEPTEMBER MONTHLY FLOW DURATION CURVE. SOURCE: WY 1968- 

2009 DAILY AVERAGE FLOW DATA. 

B-21



FIGURE 2.2-10: OCTOBER MONTHLY FLOW DURATION CURVE. SOURCE: WY 1968-2009 


B-22



FIGURE 2.2-11: NOVEMBER MONTHLY FLOW DURATION CURVE. SOURCE: WY 1968- 


B-23



FIGURE 2.2-12: DECEMBER MONTHLY FLOW DURATION CURVE. SOURCE: WY 1968- 


B-24



FIGURE 2.6-1: GROSS HEAD VS. UNIT OUTPUT 

B-26



EXHIBIT C-CONSTRUCTION HISTORY AND PROPOSED CONSTRUCTION


EXHIBIT C-CONSTRUCTION HISTORY AND PROPOSED CONSTRUCTION 

Section 1.0 

Section 2.0 


Project History ................................................................................................................ 2 

Schedule for Proposed Project Development ............................................................... 2 

C-i



EXHIBIT C – CONSTRUCTION HISTORY AND PROPOSED CONSTRUCTION 

The following excerpt from the Code of Federal Regulations (CFR) at 18 CFR § 4.51 (d) describes the 


(d) Exhibit C is a construction history and proposed construction schedule for the project. The 

construction history and schedules must contain: 

(1) If the application is for an initial license, a tabulated chronology of construction for the existing 

projects structures and facilities described under paragraph (b) of this section (Exhibit A), specifying for 

each structure or facility, to the extent possible, the actual or approximate dates (approximate dates must 

be identified as such) of: 

(i) Commencement and completion of construction or installation; 

(ii) Commencement of commercial operation; and 

(iii) Any additions or modifications other than routine maintenance; and 

(2) If any new development is proposed, a proposed schedule describing the necessary work and 

specifying the intervals following issuance of a license when the work would be commenced and 

completed. 

C-1



SECTION 1.0 

PROJECT HISTORY 

FERC regulations require a construction history only for applications for an initial license. Therefore, a 

construction history is not required for this relicensing application for the Muddy Run Pumped Storage 

Project. However, a brief Project timeline is included to provide general Project background. 

Commercial operation at Muddy Run began on April 10, 1967 when Units 1 and 2 were first 

commissioned. Units 3 and 4 were brought on-line on June 1, 1967. Units 5 and 6 began commercial 

operation on October 11, 1967. Units 7 and 8 were placed into commercial operation on February 10, 

1968. The Muddy Run powerhouse construction was completed in 1968. 

The Muddy Run Project is maintained through regularly scheduled maintenance inspections and 

replacement of deficient equipment as necessary. In addition to the routine maintenance, various areas of 

the Project have been refurbished. Major maintenance items have been completed during the life of the 

Project as follows: 

1964 FERC license to construct Muddy Run granted on September 21, 1964 

1964 Construction started 

1967 Commercial operation of units 1-6 began at various points throughout the year 

1968 Commercial operation of units 7 and 8 began on February 10, 1968 

1974-1975 Generator repairs (rotors) 

1976 Fire in potential transformer compartment 

1977-1978 Repairs to wiring in plant damaged by fire 

1983 Unit 4 generator repairs 

1984 Units 5 and 6 turbine overhauls; access road to powerhouse washed out in storm 

1985 Units 3 and 4 turbine overhauls 

1986 Units 6 and 7 turbine overhauls 

1987 Units 1 and 2 turbine overhauls; units 2 and 3 coil failures 

1989 East dike crest raised by 1.8 feet 

1994 Unit 2 stator rewind 

1995 Replacement of process control computer 

1996-1998 Runner replacement – all units 

2000 Units 1, 2 and 7 stator replacement; units 7 and 8 rotors rebuilt 

2001 Units 3, 4 rebuild rotors; units 3,5,6 and 8 stator replacement; units 5, 6 rotor replacement 

2002 Cylinder gate trash racks replaced 

SECTION 2.0 

SCHEDULE FOR PROPOSED PROJECT DEVELOPMENT 

Exelon is not proposing any new power development at the Muddy Run Pumped Storage Project. 

C-2



EXHIBIT D-STATEMENT OF COSTS AND FINANCING 

E-1




Section 1.0 Original Cost of Development ........................................................................................ 2 

Section 2.0 Amount Payable in the Event of Project Takeover ...................................................... 2 

2.1 

2.2 

2.3 

Fair Value ...................................................................................................................................... 2 

Net Investment ............................................................................................................................... 2 

Severance Damages ....................................................................................................................... 2 

Section 3.0 Capital Cost of Proposed Development ......................................................................... 3 

Section 4.0 Estimate Average Annual Cost of Project .................................................................... 3 

4.1 

4.2 

4.3 

4.4 

4.5 

Capital Costs .................................................................................................................................. 3 

Taxes .............................................................................................................................................. 3 

Depreciation and Amortization ...................................................................................................... 3 

Operation and Maintenance Expenses ........................................................................................... 3 

Costs of Environmental Measures ................................................................................................. 3 

Section 5.0 Estimated Annual Value of Project Power ................................................................... 4 

Section 6.0 Sources and Extent of Financing ................................................................................... 5 

Section 7.0 Estimate of Cost to Develop License Application ......................................................... 5 

Section 8.0 On-Peak and Off-Peak Values of Project Power.......................................................... 5 

Section 9.0 Estimated Average Annual Increase or Decrease in Project Generation .................. 6 

D-i




Table 4.5-1: Preliminary Cost Estimate of Proposed Environmental Measures ................................. 4 

Table 5-1: Valuation of the Annual Output of the Muddy Run Project ................................................ 5 

D-ii



EXHIBIT D – STATEMENT OF COSTS AND FINANCING 

The following excerpt from the Code of Federal Regulations (CFR) at 18 CFR § 4.51 (e) describes the 


(e) Exhibit D is a statement of costs and financing. The statement must contain: 

(1) If the application is for an initial license, a tabulated statement providing the actual or 

approximate original cost (approximate costs must be identified as such) of: 

(i) Any land or water right necessary to the existing project; and 

(ii) Each existing structure and facility described under paragraph(b) of this section (Exhibit A). 

(2) If the applicant is a licensee applying for a new license, and is not a municipality or a state, an 

estimate of the amount which would be payable if the project were to be taken over pursuant to 

section 14 of the Federal Power Act upon expiration of the license in effect [see 16 U.S.C. 807], 

including: 

(i) Fair value; 

(ii) Net investment; and 

(iii) Severance damages. 

(3) If the application includes proposals for any new development, a statement of estimated costs, 

including: 

(i) The cost of any land or water rights necessary to the new development; and 

(ii) The cost of the new development work, with a specification of: 

(A) Total cost of each major item; 

(B) Indirect construction costs such as costs of construction equipment, camps, and 

commissaries; 

(C) Interest during construction; and 

(D) Overhead, construction, legal expenses, taxes, administrative and general expenses, and 

contingencies. 

(4) A statement of the estimated average annual cost of the total project as proposed specifying any 

projected changes in the costs (life-cycle costs) over the estimated financing or licensing period if 

the applicant takes such changes into account, including: 

(i) Cost of capital (equity and debt); 

(ii) Local, state, and Federal taxes; 

(iii) Depreciation and amortization; 

(iv) Operation and maintenance expenses, including interim replacements, insurance, 

administrative and general expenses, and contingencies; and 

(v) The estimated capital cost and estimated annual operation and maintenance expense of each 

proposed environmental measure. 

(5) A statement of the estimated annual value of project power, based on a showing of the contract 

price for sale of power or the estimated average annual cost of obtaining an equivalent amount of 

power (capacity and energy) from the lowest cost alternative source, specifying any projected 

changes in the cost of power from that source over the estimated financing or licensing period if the 

applicant takes such changes into account. 

(6) A statement specifying the sources and extent of financing and annual revenues available to the 

applicant to meet the costs identified in paragraphs (e) (3) and (4) of this section. 

(7) An estimate of the cost to develop the license application; 

(8) The on-peak and off-peak values of project power, and the basis for estimating the values, for 

projects which are proposed to operate in a mode other than run-of-river; and 

(9) The estimated average annual increase or decrease in project generation, and the estimated 

average annual increase or decrease of the value of project power, due to a change in project 

operations (i.e., minimum bypass flows; limits on reservoir fluctuations). 

D-1



SECTION 1.0 ORIGINAL COST OF DEVELOPMENT 

This application is for a new license, not an initial license; the Muddy Run Project was originally 

licensed in 1964. Accordingly, the Commission’s regulations do not require Exelon to include a 

statement of costs of lands, water rights, structures or facilities. 18 C.F.R. § 4.51(e)(1). 

SECTION 2.0 AMOUNT PAYABLE IN THE EVENT OF PROJECT TAKEOVER 

To date, no agency or interested party has recommended a federal takeover of the Project pursuant to 

Section 14 of the Federal Power Act. If such a takeover were to occur, Exelon would have to be 

reimbursed for the net investment, not to exceed the fair value, of the property taken, plus severance 

damages, if any, to property of the licensee valuable, serviceable, and dependent for its usefulness on the 

continuance of the license, but not taken. (Section 14, Federal Power Act). 

2.1. Fair Value 

The term “fair value” is not defined in FPA Section 14. Exelon believes the best approximation of fair 

value is the cost to construct and operate a comparable power generating facility. Because of the high 

capital costs involved with constructing new facilities and the increase in fuel costs (assuming a fossil 

fueled replacement), the fair value would be considerably higher than the net investment (see Section 

2.2). If a takeover were proposed, Exelon would calculate fair value based on then-current conditions. 

2.2. Net Investment 

The Federal Power Act defines “net investment” as the original cost, plus additions, minus the sum of 

the following items (to the extent that such items have been accumulated during the period of the license 

from earnings in excess of a fair return on such investment): (a) unappropriated surplus; (b) aggregate 

credit balances of current depreciated accounts; and (c) aggregate appropriations of surplus or income 

held in amortization, sinking fund, or similar reserves. 

The Project’s net investment is $140,505,000. This should not be interpreted as the fair value of the 

Project. 

2.3. Severance Damages 

Severance damages are determined either by the cost of replacing (retiring) equipment that is “dependent 

for its usefulness upon the continuance of the License” but not taken (Section 14, Federal Power Act). 

D-2



SECTION 3.0 CAPITAL COST OF PROPOSED DEVELOPMENT 

Exelon does not propose to add any additional power generation facilities to the Project. 

SECTION 4.0 ESTIMATE AVERAGE ANNUAL COST OF PROJECT 

The average annual cost of the Project includes capital costs, taxes, depreciation, as well as operations 

and maintenance costs. The average annual costs also include any costs associated with the proposed 

protection mitigation and enhancement (PM&E) measures. 

4.1. Capital Costs 

The estimated average annual capital costs for the Project are $10,167,000. These costs include life 

cycle costs such as runner replacements, generator rewinds, and oil circuit breaker replacements and 

routine replacement of vehicles and tools. Additional capital costs related to the implementation of 

PM&E measures will add to the annual capital expense. These costs are detailed in the Section 4.5. 

4.2. Taxes 

The estimated annual property taxes are approximately $537,000. Exelon estimates paying 

approximately $26,283,000 in Project-related federal income taxes and approximately $4,504,000 in 

Project-related state income taxes annually. 

4.3. Depreciation and Amortization 

The estimated annual deprecation and amortization costs associated with the Project are $3,329,000. 

4.4. Operation and Maintenance Expenses 

Annual operations and maintenance (O&M) expenses include interim replacements, insurance, and 

administrative and general costs associated with the operation of the Project. The estimated O&M costs 

for the Project are approximately $6,857,000 per year. 

Additional O&M expenses related to the implementation of PM&E measures will add to the annual 

O&M expense. These costs are detailed in the Section 4.5. 

4.5. Costs of Environmental Measures 

Exelon proposes several environmental measures for inclusion in the new license for the Project. The 

measures would add capital costs, and increase annual operations and maintenance costs for the Project. 

D-3



Exelon estimates that the capital cost associated with Project PM&E measures will be approximately 

$3,615,000 (nominal 2014 dollars). PM&E costs will increase O&M costs by approximately $3,786,000 

(nominal 2014 dollars). 

Table 4.5-1 presents the itemized preliminary costs associated with these PM&E measures. 

TABLE 4.5-1: PRELIMINARY COST ESTIMATE OF PROPOSED ENVIRONMENTAL 

MEASURES 

PME Measure Total Capital Cost over 

46 Years (2014 dollars) 

Total O&M Cost over 46 

Years (2014 dollars) 

D-4 

Average Annual Cost 

over 46 Years (2014 

dollars) 

Bald Eagle 

Management 

$0 $53,000 $1,000 

Bog Turtle 

Management 

$0 $582,000 $13,000 

Recreation 

Management 

$3,607,000 $3,151,000 $147,000 

Shoreline 

Management 

TBD TBD TBD 

Historic 

Properties 

$8,000 $0 $0 

Total $3,615,000 $3,786,000 $161,000 

SECTION 5.0 ESTIMATED ANNUAL VALUE OF PROJECT POWER 

If all Project generation was sold into the market, it would be priced at the Day Ahead and Real Time 

Locational Marginal Prices that clear for each generator. For 2011, the Project had a realized generation 

energy value of $70.25/MWh and a pumping energy value of $32.77/MWh (this is a realized value 

calculated as revenue divided by generation). 

The economic analysis of the Project also recognizes that the PJM market values the installed capacity 

and ancillary services provided by generation facilities. Installed Capacity (ICAP) is required by PJM to 

ensure the reliability of the electric system. ICAP is compensated in terms of Unforced Capacity 

(UCAP) within PJM where UCAP =ICAP*(1-EFORd 4 ). UCAP price is established by PJM through an 

RPM (Reliability Pricing Model) auction process. The calendar average RPM clearing price was 

4 EFORd = Equivalent Forced Outage Rate.



$136.60/MW-day. The Project’s UCAP value is 1,060.6 MW. Thus, the annual capacity value of the 

Project for 2011 is approximately $52.8 million (1,060.6 MW * $136.60/MW-day * 365 days/yr). 

In addition to energy and capacity, the Project produces ancillary services that provide regulation 

service, spinning and scheduling reserve, voltage control and black start capability to the PJM market. 

For 2011, the ancillary services revenue has been calculated as $10,819,000 per year. 

Table 5-1 below shows the total valuation of the power based on the product components identified 

above. This assumes an average generation, of 1,739,000 MWh and use of 2,261,000 MWh annually, 

based on the Exelon operations model. The annual market value of the energy, capacity and ancillaries 

is approximately $$111,771,000, which equates to $64.27 per MWh. 

TABLE 5-1: VALUATION OF THE ANNUAL OUTPUT OF THE MUDDY RUN PROJECT 

Energy Generated at $70.25 (for 1,739,000 MWh) $122,165,000 

Energy for Pumping at $32.77 (for 2,261,000 MWh) ($74,093,000) 

UCAP at $136.60 per MW-day (1,060.6 MW) $52,880,000 

Ancillary Services $10,819,000 

Total Value (Energy + Ancillary Services + UCAP) $111,771,000 

Total value per MWh (generated) $64.27 

SECTION 6.0 SOURCES AND EXTENT OF FINANCING 

Exelon finances capital projects using a combination of debt obligations and internal funding sources. 

Based on the value of Project power (Section 5.0), the Project has adequate financial resources for the 

operation of the Project for the term of a new license (Section 4.0). 

SECTION 7.0 ESTIMATE OF COST TO DEVELOP LICENSE APPLICATION 

The cost to develop the information necessary to complete the Muddy Run Project license application is 

estimated to be $7,026,000. This estimate includes all study costs, ILP costs, and personnel and 

administrative costs associated with processing. 

SECTION 8.0 ON-PEAK AND OFF-PEAK VALUES OF PROJECT POWER 

The Conowingo Project operates within the Pennsylvania-New Jersey-Maryland (PJM) Interconnection, 

whose geographic area includes that of the Mid-Atlantic Area Council (MAAC) region. 

D-5



Exelon has provided the historical 2011 Real Time On Peak and Off-Peak prices for the Muddy Run 

generation node 5 . 

On Peak Price $53.04/MWh 

Off-Peak Price $37.45/MWh 

SECTION 9.0 ESTIMATED AVERAGE ANNUAL INCREASE OR DECREASE IN PROJECT 

GENERATION 

No changes in operations of the Project are proposed, and therefore no increases or decreases in Project 

generation are expected. 

5 The electricity values referenced were internally generated from an Exelon software application. This application 

software retrieves PJM data such as LMP electricity prices directly from the PJM database. Exelon’s program 

retrieves data every hour and also on a daily and monthly basis. The data referenced was the historical Real Time 

LMP values for Muddy Run for 2011. The Muddy Run Pricing node (Pnode) ID is #734134. For reference, the 

URL for PJM data is http://www.pjm.com/pub/account/lmp/20120801.csv (data for August 1st 2012). 

D-6



EXHIBIT E-ENVIRONMENTAL REPORT 

E-1

Section 1.0 




Introduction ..................................................................................................................... 5 

1.1. Exelon’s Application for a New License ....................................................................................... 5 

1.2. Purpose of Action and Need for Power ......................................................................................... 5 

1.2.1. Purpose of Actions .................................................................................................................... 5 

1.2.2. Need for Power .......................................................................................................................... 6 

1.3. Applicable Statutory and Regulatory Requirements...................................................................... 7 

1.3.1. Federal Power Act ..................................................................................................................... 7 

1.3.2. National Historic Preservation Act of 1966 .............................................................................. 7 

1.3.3. Clean Water Act of 1970 ........................................................................................................... 8 

1.3.4. Endangered Species Act of 1973 ............................................................................................... 8 

1.3.5. Energy Policy Act of 2005 ........................................................................................................ 9 

1.4. Public Review and Consultation .................................................................................................... 9 

1.4.1. Scoping ...................................................................................................................................... 9 

1.4.2. Interventions ............................................................................................................................ 10 

1.4.3. Relicensing Studies ................................................................................................................. 10 

1.4.4. Comments on the Draft License Application .......................................................................... 12 

1.4.5. Comments on the Final License Application .......................................................................... 13 

1.4.6. Comments on the Draft Environmental Assessment ............................................................... 13 

Section 2.0 

Proposed Action and Alternatives ............................................................................... 16 

2.1. No Action Alternative .................................................................................................................. 16 

2.1.1. Existing Project Facilities ........................................................................................................ 16 

2.1.2. Existing Project Boundary ....................................................................................................... 17 

2.1.3. Existing Project Safety ............................................................................................................ 18 

2.1.4. Existing Project Operations ..................................................................................................... 18 

2.1.5. Existing Environmental Measures and Recreation Facilities .................................................. 18 

2.2. Exelon’s Proposal ........................................................................................................................ 20 

2.2.1. Proposed Project Facilities ...................................................................................................... 20 

2.2.2. Proposed Project Boundary ..................................................................................................... 21 

2.2.3. Proposed Project Safety ........................................................................................................... 21 

2.2.4. Proposed Project Operations ................................................................................................... 21 

2.2.5. Proposed Environmental Measures ......................................................................................... 22 

2.3. Alternatives Considered But Eliminated From Further Analysis ................................................ 23 

2.3.1. Retire the Project ..................................................................................................................... 23 

2.3.2. Issue a Non-Power License ..................................................................................................... 24 

2.3.3. Federal Agency Takeover of the Project ................................................................................. 25 

Section 3.0 

Environmental Analysis ............................................................................................... 28 

E-i



3.1. General Description of the River Basin ....................................................................................... 28 

3.1.1. Topography ............................................................................................................................. 28 

3.1.2. Climate .................................................................................................................................... 29 

3.1.3. Land and Water Use ................................................................................................................ 29 

3.2. Cumulative Effects Analysis ....................................................................................................... 39 

3.2.1. Cumulatively Affected Resources ........................................................................................... 39 

3.2.2. Geographic Scope of Analysis for Cumulatively Affected Resources .................................... 39 

3.2.3. Temporal Scope of Analysis for Cumulatively Affected Resources ....................................... 40 

3.2.4. Past, Present and Reasonably Foreseeable Future Actions ..................................................... 40 

3.3. Proposed Action and Action Alternative ..................................................................................... 40 

3.3.1. Geology and Soils ................................................................................................................... 40 

3.3.2. Water Resources ...................................................................................................................... 60 

3.3.3. Aquatic Resources ................................................................................................................... 82 

3.3.4. Terrestrial Resources ............................................................................................................. 119 

3.3.5. Threatened and Endangered Species ..................................................................................... 136 

3.3.6. Recreational Resources ......................................................................................................... 147 

3.3.7. Land Use ............................................................................................................................... 164 

3.3.8. Cultural Resources ................................................................................................................ 173 

3.3.9. Aesthetic and Noise Resources ............................................................................................. 190 

3.3.10. Socio-Economic Resources ................................................................................................... 197 

3.4. No-Action Alternative ............................................................................................................... 205 

Section 4.0 

Developmental Analysis .............................................................................................. 206 

4.1. Power and Economic Benefits of the Project ............................................................................ 206 

4.1.1. Economic Assumptions ......................................................................................................... 206 

4.1.2. Annual Power Value ............................................................................................................. 207 

4.1.3. Project Costs under No-Action Alternative ........................................................................... 207 

4.1.4. Project Costs under Proposed Alternative ............................................................................. 208 

4.2. Comparison of Alternatives ....................................................................................................... 208 

4.2.1. No Action Alternative ........................................................................................................... 209 

4.2.2. Proposed Alternative ............................................................................................................. 209 

Section 5.0 

Conclusions .................................................................................................................. 210 

5.1. Comparison of Alternatives ....................................................................................................... 210 

5.2. Comparison Development and Recommended Alternative ....................................................... 210 

5.3. Unavoidable Adverse Effects .................................................................................................... 210 

5.4. Consistency with Comprehensive Plans .................................................................................... 210 

Section 6.0 

Section 7.0 

Literature Cited........................................................................................................... 219 

Consultation Documentation ..................................................................................... 229 

E-ii



APPENDIX A - RESPONSE TO COMMENTS RECEIVED ON DRAFT LICENSE 

APPLICATION....................................................................................................................................... 245 


Table 1.4.1-1: Scoping Comment Summary ........................................................................................... 14 

Table 1.4.4-1: Licensing Study Summary ............................................................................................... 15 

Table 3.1-1: Characteristics of the Susquehanna River Subbasins ...................................................... 33 

Table 3.1.3.3-1: Hydropower in the Lower Susquehanna River Subbasin .......................................... 34 

Table 3.1.3.4-1: Major Tributaries to the Lower Susquehanna River ................................................. 35 

Table 3.3.1.1.2-1: Bedrock Geologic Units of the Project Area ............................................................ 46 

Table 3.3.1.1.3-1: Surficial Geologic Units of the Project Area ............................................................ 47 

Table 3.3.1.1.4-1: Soil Units of Project Area in Muddy Run Reservoir Area ..................................... 48 

Table 3.3.1.1.4-2: Soil Units of Project Area in Transmission Line Corridor ..................................... 50 

Table 3.3.2.1.1-1: Conowingo Annual and Monthly Sub-Daily (30-Minute) Flow Exceedance 

Percentiles, in CFS (WY 1989-1990, 1992-1993, 1995-2009) ......................................................... 75 

Table 3.3.2.1.1-2: Marietta Annual and Monthly Sub-Daily (30-Minute) Flow Exceedance 

Percentiles, in CFS (WY 1989-1990, 1992-1993, 1995-2009) ......................................................... 76 

Table 3.3.2.1.1-3: Water Withdrawal and Return Statistics for 30-day High-Flow Periods ............. 77 

Table 3.3.2.1.1-4: Water Withdrawal and Return Statistics for 30-day Low-Flow Periods .............. 77 

Table 3.3.2.1.2-1: Summary of Pennsylvania Protected Water Use Categories .................................. 78 

Table 3.3.2.1.2-2: Pennsylvania’s Maximum Water Temperature Criteria specified for Warm 

Water Fisheries ................................................................................................................................. 79 

Table 3.3.2.1.2-3: Summary of Water Quality Data Collected from the Muddy Run Project 

Discharge from 8/8/2006 to 9/3/2006 ............................................................................................... 79 

Table 3.3.3.1-1: Fish Species Known to Occur in Muddy Run Power Reservoir and Recreation Lake 

.......................................................................................................................................................... 109 

Table 3.3.1.1-2: Fish Species Composition in Conowingo Pond, 2010-11 .......................................... 111 

Table 3.3.1.1-3: Comparison of Creel Surveys at Muddy Run Recreation Lake. ............................. 111 

E-iii



Table 3.3.3.1-4: Estimated Catch and Harvest Totals on Conowingo Pond in 2010 ........................ 112 

Table 3.3.3.1-5: Benthic Macroinvertebrates Identified in Conowingo Pond and Muddy Run 

Reservoir .......................................................................................................................................... 113 

Table 3.3.3.1-6: Algal Species Identified in Conowingo Pond and Muddy Run Reservoir .............. 116 

Table 3.3.3.1-7: Zooplankton Species Identified in Muddy Run Reservoir....................................... 118 

Table 3.3.4.1.3-1: Avian Species Seen or Heard during Surveys (2010 – 2011) ................................ 131 

Table 3.3.4.1.3-2: Amphibians and Reptiles Observed during Herp Surveys (2010-2011) .............. 133 

Table 3.3.6.1-1: Recreation Projection Index, through 2050 (a) Northeast Region .......................... 160 

Table 3.3.6.1-2: Recreation Activity in Terms of Recreation Days by Location, Summary, 2050 (a) 

Muddy Run Project ........................................................................................................................ 161 

Table 3.3.6.1-3: Projected Average Weekend Summer Parking Lot Use by Location, Summary, 

2050 Muddy Run Project ............................................................................................................... 162 

Table 3.3.6.2-1: Recreation Facility Enhancement Costs .................................................................... 162 

Table 3.3.9-1: Audio Assessment Measurement Results ..................................................................... 196 

Table 3.3.10.1.2-1: Population of Pennsylvania, Lancaster and York Counties and Communities, 

1980- 2020. ....................................................................................................................................... 202 

Table 3.3.10.1.2-2: Lancaster and York Counties and Communities Population Change, 1980-2020. 

.......................................................................................................................................................... 203 

Table 3.3.10.1.2-3: Per Capita Income for Pennsylvania, Lancaster and York County. ................. 203 

Table 3.3.10.1.2-4: Median Household Income for Pennsylvania, Lancaster and York County. .... 203 

Table 3.3.10.1.2-5 Pennsylvania, Lancaster and York County Civilian Labor Force Data ............. 204 

Table 4.1.1-1: Assumptions for Economic Analysis ............................................................................. 206 

Table 4.1.2-1: Valuation of the Annual Output of the Muddy Run Project ...................................... 207 

Table 4.1.3-1: Summary of Annual Costs under the No Action Alternative. .................................... 208 

Table 4.1.4-1: Summary of Annualized Costs (2014 dollars) for Environmental and Recreation 

Measures .......................................................................................................................................... 208 

Table 4.2-1: Comparison of the Power Value, Annual Costs, and Net Benefits of the No Action and 

Proposed Alternatives. .................................................................................................................... 209 

E-iv




Figure 2.1.1-1: Muddy Run Project Facilities ........................................................................................ 26 

Figure 2.1.2-1: Project Location Map ..................................................................................................... 27 

Figure 3.1-1: Susquehanna River Basin Map ......................................................................................... 36 

Figure 3.1.3.4-1: Major Tributaries to the Susquehanna River in Lower Susquehanna River 

Subbasin ............................................................................................................................................. 38 

Figure 3.3.1.1-1: Bedrock Geology .......................................................................................................... 51 

Figure 3.3.1.1.4-1: Soils within 2000 Feet of Muddy Run Main Parcel................................................ 52 

Figure 3.3.1.1.4-2: Soils within 2000 Feet of Muddy Run Transmission Parcels ................................ 53 

Figure3.3.1.1.5-1: Weathered Bedrock ................................................................................................... 54 

Figure 3.3.1.1.5-2: Outcropping Bedrock ............................................................................................... 55 

Figure 3.3.1.1.5-3: In Situ Tree Stumps .................................................................................................. 56 

Figure 3.3.1.1.5-4: Meandering Thalwegs ............................................................................................... 57 

Figure 3.3.1.1.7-1: Erosion at Recreation Dam ...................................................................................... 58 

Figure 3.3.1.1.8-1: Shoreline Erosion Inventory .................................................................................... 59 

Figure 3.3.4.1.4-1: Muddy Run NWI Wetlands ................................................................................... 135 

Figure 3.3.6.1-1: Muddy Run Recreation Facilities ............................................................................. 163 

Figure 3.3.7.1-1: Muddy Run Land Use Classifications ...................................................................... 171 

Figure 3.3.7.1-2: Muddy Run Land Use with Sensitive Resources ..................................................... 172 

E-v



EXHIBIT E – ENVIRONMENTAL REPORT 

The following excerpt from the Code of Federal Regulations (CFR) at 18 CFR § 5.18(b) describes the 


Exhibit E—Environmental Exhibit. The specifications for Exhibit E in §§4.41, 4.51, or 4.61 of this 

chapter shall not apply to applications filed under this part. The Exhibit E included in any license 

application filed under this part must address the resources listed in the Pre-Application Document 

provided for in §5.6; follow the Commission’s “Preparing Environmental Assessments: Guidelines for 

Applicants, Contractors, and Staff,” as they may be updated from time-to-time; and meet the following 

format and content requirements: 

(1) General description of the river basin. Describe the river system, including relevant tributaries; give 

measurements of the area of the basin and length of stream; identify the project’s river mile designation 

or other reference point; describe the topography and climate; and discuss major land uses and economic 

activities. 

(2) Cumulative effects. List cumulatively affected resources based on the Commission’s Scoping 

Document, consultation, and study results. Discuss the geographic and temporal scope of analysis for 

those resources. Describe how resources are cumulatively affected and explain the choice of the 

geographic scope of analysis. Include a brief discussion of past, present, and future actions, and their 

effects on resources based on the new license term (30–50 years). Highlight the effect on the cumulatively 

affected resources from reasonably foreseeable future actions. Discuss past actions’ effects on the 

resource in the Affected Environment Section. 

(3) Applicable laws. Include a discussion of the status of compliance with or consultation 

under the following laws, if applicable: 

(i) Section 401 of the Clean Water Act. The applicant must file a request for a water quality 

certification (WQC), as required by Section 401 of the Clean Water Act no later than the deadline 

specified in §5.23(b). Potential applicants are encouraged to consult with the certifying agency or 

tribe concerning information requirements as early as possible. 

(ii) Endangered Species Act (ESA). Briefly describe the process used to address project effects on 

Federally listed or proposed species in the project vicinity. Summarize any anticipated environmental 

effects on these species and provide the status of the consultation process. If the applicant is the 

Commission’s non-Federal designee for informal consultation under the ESA, the applicant’s draft 

biological assessment must be included. 

(iii) Magnuson-Stevens Fishery Conservation and Management Act. Document from the National 

Marine Fisheries Service (NMFS) and/or the appropriate Regional Fishery Management Council any 

essential fish habitat (EFH) that may be affected by the project. Briefly discuss each managed species 

and life stage for which EFH was designated. Include, as appropriate, the abundance, distribution, 

available habitat, and habitat use by the managed species. If the project may affect EFH, prepare a 

draft “EFH Assessment” of the impacts of the project. The draft EFH Assessment should contain the 

information outlined in 50 CFR 600.920(e). 

(iv) Coastal Zone Management Act (CZMA). Section 307(c)(3) of the CZMA requires that all 

Federally licensed and permitted activities be consistent with approved state Coastal Zone 

Management Programs. If the project is located within a coastal zone boundary or if a project affects 

a resource located in the boundaries of the designated coastal zone, the applicant must certify that 

the project is consistent with the state Coastal Zone Management Program. If the project is within or 

affects a resource within the coastal zone, provide the date the applicant sent the consistency 

certification information to the state agency, the date the state agency received the certification, and 

the date and action taken by the state agency (for example, the agency will either agree or disagree 

with the consistency statement, waive it, or ask for additional information). Describe any conditions 

placed on the state agency’s concurrence and assess the conditions in the appropriate section of the 

license application. If the project is not in or would not affect the coastal zone, state so and cite the 

coastal zone program office’s concurrence. 

E-1



(v) National Historic Preservation Act (NHPA). Section 106 of NHPA requires the Commission to 

take into account the effect of licensing a hydropower project on any historic properties, and allow 

the Advisory Council on Historic Preservation (Advisory Council) a reasonable opportunity to 

comment on the proposed action. “Historic Properties” are defined as any district, site, building, 

structure, or object that is included in or eligible for inclusion in the National Register of Historic 

Places (NRHP). If there would be an adverse effect on historic properties, the applicant may include 

a Historic Properties Management Plan (HPMP) to avoid or mitigate the effects. The applicant must 

include documentation of consultation with the Advisory Council, the State Historic Preservation 

Officer, Tribal Historic Preservation Officer, National Park Service, members of the public, and 

affected Indian tribes, where applicable. 

(vi) Pacific Northwest Power Planning and Conservation Act (Act). If the project is not within the 

Columbia River Basin, this section shall not be included. The Columbia River Basin Fish and Wildlife 

Program (Program) developed under the Act directs agencies to consult with Federal and state fish 

and wildlife agencies, appropriate Indian tribes, and the Northwest Power Planning Council 

(Council) during the study, design, construction, and operation of any hydroelectric development in 

the basin. Section 12.1A of the Program outlines conditions that should be provided for in any 

original or new license. The program also designates certain river reaches as protected from 

development. The applicant must document consultation with the Council, describe how the act 

applies to the project, and how the proposal would or would not be consistent with the program. 

(vii) Wild and Scenic Rivers and Wilderness Acts. Include a description of any areas within or in the 

vicinity of the proposed project boundary that are included in, or have been designated for study for 

inclusion in, the National Wild and Scenic Rivers System, or that have been designated as wilderness 

area, recommended for such designation, or designated as a wilderness study area under the 

Wilderness Act. 

(4) Project facilities and operation. Provide a description of the project to include: 

(i) Maps showing existing and proposed project facilities, lands, and waters within the project 

boundary; 

(ii) The configuration of any dams, spillways, penstocks, canals, powerhouses, tailraces, and other 

structures; 

(iii) The normal maximum water surface area and normal maximum water surface elevation (mean 

sea level), gross storage capacity of any impoundments; 

(iv) The number, type, and minimum and maximum hydraulic capacity and installed (rated) capacity 

of existing and proposed turbines or generators to be included as part of the project; 

(v) An estimate of the dependable capacity, and average annual energy production in kilowatt hours 

(or mechanical equivalent); 

(vi) A description of the current (if applicable) and proposed operation of the project, including any 

daily or seasonal ramping rates, flushing flows, reservoir operations, and flood control operations. 

(5) Proposed action and action alternatives. 

(i) The environmental document must explain the effects of the applicant’s proposal on resources. 

For each resource area addressed includes: 

(A) A discussion of the affected environment; 

(B) A detailed analysis of the effects of the applicant’s licensing proposal and, if reasonably 

possible, any preliminary terms and conditions filed with the Commission; and 

(C) Any unavoidable adverse impacts. 

(ii) The environmental document must contain, with respect to the resources listed in the Pre- 

Application Document provided for in §5.6, and any other resources identified in the Commission’s 

scoping document prepared pursuant to the National Environmental Policy Act and §5.8, the 

following information, commensurate with the scope of the project: 

(A) Affected environment. The applicant must provide a detailed description of the affected 

environment or area(s) to be affected by the proposed project by each resource area. This 

E-2



description must include the information on the affected environment filed in the Pre-Application 

Document provided for in §5.6, developed under the applicant’s approved study plan, and 

otherwise developed or obtained by the applicant. This section must include a general description 

of socio-economic conditions in the vicinity of the project including general land use patterns 

(e.g., urban, agricultural, forested), population patterns, and sources of employment in the 

project vicinity. 

(B) Environmental analysis. The applicant must present the results of its studies conducted under 

the approved study plan by resource area and use the data generated by the studies to evaluate 

the beneficial and adverse environmental effects of its proposed project. This section must also 

include, if applicable, a description of any anticipated continuing environmental impacts of 

continued operation of the project, and the incremental impact of proposed new development of 

project works or changes in project operation. This analysis must be based on the information 

filed in the Pre-Application Document provided for in §5.6, developed under the applicant’s 

approved study plan, and other appropriate information, and otherwise developed or obtained by 

the Applicant. 

(C) Proposed environmental measures. The applicant must provide, by resource area, any 

proposed new environmental measures, including, but not limited to, changes in the project 

design or operations, to address the environmental effects identified above and its basis for 

proposing the measures. The applicant must describe how each proposed measure would protect 

or enhance the existing environment, including, where possible, a non-monetary quantification of 

the anticipated environmental benefits of the measure. This section must also include a statement 

of existing measures to be continued for the purpose of protecting and improving the environment 

and any proposed preliminary environmental measures received from the consulted resource 

agencies, Indian tribes, or the public. If an applicant does not adopt a preliminary environmental 

measure proposed by a resource agency, Indian tribe, or member of the public, it must include its 

reasons, based on project specific information. 

(D) Unavoidable adverse impacts. Based on the environmental analysis, discuss any adverse 

impacts that would occur despite the recommended environmental measures. Discuss whether 

any such impacts are short- or long-term, minor or major, cumulative or site-specific. 

(E) Economic analysis. The economic analysis must include annualized, current cost-based 

information. For a new or subsequent license, the applicant must include the cost of operating 

and maintaining the project under the existing license. For an original license, the applicant must 

estimate the cost of constructing, operating, and maintaining the proposed project. For either 

type of license, the applicant should estimate the cost of each proposed resource protection, 

mitigation, or enhancement measure and any specific measure filed with the Commission by 

agencies, Indian tribes, or members of the public when the application is filed. For an existing 

license, the applicant’s economic analysis must estimate the value of developmental resources 

associated with the project under the current license and the applicant’s proposal. For an 

original license, the applicant must estimate the value of the developmental resources for the 

proposed project. As applicable, these developmental resources may include power generation, 

water supply, irrigation, navigation, and flood control. Where possible, the value of 

developmental resources must be based on market prices. If a protection, mitigation, or 

enhancement measure reduces the amount or value of the project’s developmental resources, the 

applicant must estimate the reduction. 

(F) Consistency with comprehensive plans. Identify relevant comprehensive plans and explain 

how and why the proposed project would, would not, or should not comply with such plans and a 

description of any relevant resource agency or Indian tribe determination regarding the 

consistency of the project with any such comprehensive plan. 

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(G) Consultation Documentation. Include a list containing the name, and address of every 

Federal, state, and interstate resource agency, Indian tribe, or member of the public with which 

the applicant consulted in preparation of the Environmental Document. 

H) Literature cited. Cite all materials referenced including final study reports, journal articles, 

other books, agency plans, and local government plans. 

(6) The applicant must also provide in the Environmental Document: 

(A) Functional design drawings of any fish passage and collection facilities or any other facilities 

necessary for implementation of environmental measures, indicating whether the facilities 

depicted are existing or proposed (these drawings must conform to the specifications of §4.39 of 

this chapter regarding dimensions of full-sized prints, scale, and legibility); 

(B) A description of operation and maintenance procedures for any existing or proposed 

measures or facilities; 

(C) An implementation or construction schedule for any proposed measures or facilities, showing 

the intervals following issuance of a license when implementation of the measures or construction 

of the facilities would be commenced and completed; 

(D) An estimate of the costs of construction, operation, and maintenance, of any proposed 

facilities, and of implementation of any proposed environmental measures. 

(E) A map or drawing that conforms to the size, scale, and legibility requirements of §4.39 of this 

chapter showing by the use of shading, cross-hatching, or other symbols the identity and location 

of any measures or facilities, and indicating whether each measure or facility is existing or 

proposed (the map or drawings in this exhibit may be consolidated). 

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SECTION 1.0 



INTRODUCTION 

1.1. Exelon’s Application for a New License 

Exelon Generation Company, LLC (Exelon or Licensee), in accordance with Sections (§§) 5.17 and 5.18 

of Title 18 of the Code of Federal Regulations (CFR) will file with the Federal Energy Regulatory 

Commission (FERC or Commission) an Application for a New License for Major Project – Existing Dam 

- for Exelon’s 800 megawatt (MW) Muddy Run Pumped Storage Project, FERC Project No. 2355 

(Project). The initial license for the Project was issued by the Federal Power Commission (FPC), FERC’s 

predecessor, to Susquehanna Power Company and Philadelphia Electric Power Company. The license 

was issued on September 21, 1964, for a term ending August 31, 2014. 

Project facilities and features of the existing FERC license for pump storage operation include the dam 

creating the Muddy Run upper reservoir, as well as three other structures: an east dike, a recreation pond 

dike, and an intake canal embankment. The upper reservoir is connected to the powerhouse by four 

intake cylinders and tunnels, which bifurcate into eight penstocks which in turn feed each of the Project’s 

pump/turbines. The Project’s lower reservoir, Conowingo Pond, is located on the Susquehanna River. 

The Conowingo Pond also serves as the impoundment for the adjacent Conowingo FERC Project (FERC 

No. 405). The Project also includes a primary transmission line, which extends from the powerhouse 

across Conowingo Pond and travels approximately four miles to the PBAPS substation in York County, 

PA. All of the lands within the Project boundary are private lands owned by Exelon. 

Exelon proposes to continue to operate the Muddy Run Pumped Storage Project as it has operated 

historically. Exelon is not proposing any changes to the existing power production facilities or Project 

operations. Exelon is proposing the implementation of several resource management plans and a 

comprehensive management and upgrade proposal for the recreational facilities at the Muddy Run 

Project. 

1.2. Purpose of Action and Need for Power 

1.2.1. Purpose of Actions 

FERC must decide whether to issue a new hydropower license to Exelon for the Muddy Run Project and 

what conditions should be placed on any license issued. In deciding whether and under what conditions 

to issue a license for a hydroelectric project, pursuant to Section 10(a)(1) of the Federal Power Act (FPA), 

FERC must determine that the project will be best adapted to a comprehensive plan for improving or 

developing the waterway. In addition to the power and developmental purposes for which licenses are 

E-5



issued, FERC is required under Section 4 (e) of the FPA to give equal consideration to the purposes of 

energy conservation, the protection, mitigation of damage to, and enhancement of, fish and wildlife 

(including related spawning grounds and habitat), the protection of recreational opportunities, and the 

preservation of other aspects of environmental quality. 

Issuing a new license for the Project would allow Exelon to continue to generate and transmit electricity 

at the Project for the term of the new license, making electric power from a renewable resource available 

to its customers. 

Exhibit E of this license application has been prepared in accordance with 18 CFR § 5.18(b) and in 

general conformance with the Commission’s Preparing Environmental Assessments: Guidelines for 

Applicants, Contractors and Staff (FERC 2008). This Exhibit E is designed to support FERC’s required 

analysis under the National Environmental Policy Act of 1969 (NEPA), as amended. The Exhibit 

analyzes the environmental and economic effects associated with the continued operation of the Muddy 

Run Project, as proposed by Exelon. This Exhibit includes measures proposed by Exelon for the PM&E 

of resources that would potentially be affected by Exelon’s proposed Project. The effects of a no-action 

alternative are also considered. 

1.2.2. Need for Power 

The Muddy Run Project is located within the PJM Regional Transmission Organization (RTO) which is 

responsible for the movement of wholesale power in thirteen eastern states and the District of Columbia. 

PJM prepares a 15-year load projection in energy demand, which it utilizes to plan improvements to the 

existing transmission system. PJM currently predicts that in the Mid-Atlantic region, peak summer 

energy usage demand for the 15-year period from 2010 through 2024 is forecasted to increase by 1.5 

percent (PJM 2011). Over the term of the new license, Muddy Run will provide power and ancillary 

services to help meet this growing demand. 

The Project also is capable of providing “black start” service. Black start is the procedure used to recover 

from a total or partial loss of the transmission system by starting individual stations independently of the 

grid and gradually reenergizing the interconnected system. In the event that the regional grid loses all 

power, Exelon can bring the Muddy Run Project online using installed station batteries to begin the 

process of returning power to the grid. 

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1.3. Applicable Statutory and Regulatory Requirements 

Issuing a new license for the Project is subject to numerous requirements under the FPA and other 

applicable statutes. The major acts and related requirements are described below. Actions undertaken by 

Exelon or the agency with jurisdiction related to each requirement are also described. 

1.3.1. Federal Power Act 

1.3.1.1 Section 10(j) Recommendations 

Under the provisions of Section 10(j) of the FPA, each hydroelectric license issued by FERC is required 

to include conditions based on recommendations of federal and state fish and wildlife agencies for the 

protection, mitigation or enhancement of fish and wildlife resources affected by the Project, unless FERC 

determines they are inconsistent with the purposes and requirements of the FPA or other applicable law. 

During the relicensing, Exelon consulted with the Pennsylvania Department of Environmental Protection 

(PADEP), the Pennsylvania Fish and Boat Commission (PFBC), Susquehanna River Basin Commission 

(SRBC), and the United States Fish and Wildlife Service (USFWS). 

1.3.1.2 Section 18 Fishway Prescriptions 

Section 18 of the FPA, 16 U.S.C. § 811, states that FERC shall require construction, maintenance, and 

operation by a licensee of such fishways as the secretaries of the Department of Commerce and the 

Department of the Interior (DOI) may prescribe. Exelon has consulted with the USFWS during 

implementation of the ILP, including study plan development. 

1.3.2. National Historic Preservation Act of 1966 

As the lead Federal agency for hydropower relicensing, FERC is responsible for satisfying Section 106 

consultation requirements under the National Historic Preservation Act (NHPA). Implementation 

regulations for Section 106 have been published by the Secretary of the Interior in 36 CFR 800. FERC 

must consult with interested parties, including the Pennsylvania Historical and Museum Commission, 

Bureau for Historic Preservation (PHMC) and all Tribes which may have used the area in the past on 

Project effects on historic properties eligible for protection under the NHPA. This consultation must 

document that FERC has considered the effects of the undertaking (the issuance of a new federal 

operating license) on historic properties eligible for listing on the National Register of Historic Places 

(NRHP) and allow the Advisory Council on Historic Preservation (ACHP) a reasonable opportunity to 

comment on its conclusions. FERC typically satisfies Section 106 requirements by delegating day-to-day 

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consultation and study authority to the Licensee. FERC delegated this authority to Exelon by letter dated 

May 11, 2009. 

Exelon developed a study plan to identify and assess, in consultation with the PHMC and potentially 

affected Indian tribes, any adverse effects on historic properties resulting from continued operation of the 

Project, as required under 36 CFR § 800.5. If necessary, based on consultation with the PHMC and 

Indian tribes and other interested parties, Exelon will develop a Historic Properties Management Plan 

(HPMP) in consultation with these same parties. 

1.3.3. Clean Water Act of 1970 

Section 401 of the Clean Water Act (CWA) requires Exelon to obtain state certification of the Project’s 

compliance with applicable provisions of the CWA, or a waiver of certification from the appropriate state 

agency. FERC regulations require that a request for CWA Section 401 certification be filed within 60 

days of FERC’s issuance of a notice of acceptance and ready for environmental analysis (REA). During 

the relicensing, Exelon consulted with the Office of Water Management of the Pennsylvania Department 

of Environmental Protection. Exelon is prepared to file its application for CWA Section 401 certification 

in a timely manner. 

Water quality standards for Muddy Run Project waters are established by the Bureau of Water Standards 

and Facility Regulation, Water Quality Standards Division, of the PADEP. The water quality standards 

applicable to the Project are contained in the 2010 Pennsylvania Integrated Water Quality Monitoring and 

Assessment Report (WQMAR). 

1.3.4. Endangered Species Act of 1973 

The Endangered Species Act (ESA) of 1973, as amended, (16 USC § 1531 et seq.) was enacted to protect 

and conserve endangered and threatened species and the ecosystems upon which they depend. The ESA 

defines an “endangered” species in part as a, “species which is in danger of extinction throughout all or a 

significant portion of its range” and a “threatened” species as one, “which is likely to become an 

endangered species within the foreseeable future throughout all or a significant portion of its range.” (16 

USC § 1532(6)). A species may be officially proposed for listing under the ESA as endangered or 

threatened. The ESA is administered by the Secretary of the Interior through USFWS for most species, 

and by the Secretary of Commerce through the National Marine Fisheries Service (NMFS for marine and 

anadromous species. 

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Section 7 of the ESA requires federal agencies to consult with the USFWS and National Marine Fisheries 

Service (NMFS) to ensure that any action that they authorize, fund, or carry out is not likely to jeopardize 

the continued existence of any threatened or endangered species, or result in the destruction or adverse 

modification of critical habitat for these listed species. 

Section 7 consultation with the USFWS and NMFS is ongoing 

1.3.5. Energy Policy Act of 2005 

The Energy Policy Act of 2005, as amended (P.L. 109-58) provides parties 6 to a licensing proceeding the 

opportunity to propose alternatives to preliminary conditions and to request trial-type hearings regarding 

issues of material fact that support the preliminary conditions developed under FPA § 18. 

1.4. Public Review and Consultation 

The Commission’s regulations (18 CFR §§ 5.1-5.16) require that an applicant consult with appropriate 

federal and state agencies, local governments, Indian tribes, non-governmental organizations (NGO), 

businesses and unaffiliated members of the public that may be interested in the proceeding before filing 

an application for a license. This consultation is the first step in complying with FPA, ESA, NHPA, and 

other federal statutes. Pre-filing consultation must be complete and documented according to the 

Commission’s regulations. Confirmation of Exelon’s prefiling consultation is included in Exhibit E, 

Section 7 of the license application. 

1.4.1. Scoping 

Under the Commission’s regulations, issuing a licensing decision for any project first requires preparation 

of either an EA or an EIS, in accordance with NEPA. The preparation of an EA or EIS is supported by a 

scoping process to ensure the identification and analysis of all pertinent issues. 

On May 11, 2009, the Commission issued a notice of commencement of proceeding stating FERC 

intended to prepare an EA for the Project but noting there was a possibility that an EIS would be required. 

At the same time, the Commission issued Scoping Document 1 (SD1). SD1 provided Relicensing 

Participants with FERC’s preliminary list of issues and alternatives to be addressed in an EA, or EIS, for 

6 License parties are defined in 18 CFR §385.102(c), and includes, with respect to a proceeding, a person (or entity) 

filing any application, petition, tariff or rate filing, complaint, or any protest under section 19a(i) of the Interstate 

Commerce Act (49 U.S.C. 19a(i)). 

E-9



the Project relicensing and enabled Relicensing Participants to more effectively participate in and 

contribute to the scoping process. 

The Commission held two public scoping meetings in Holtwood, Pennsylvania on June 10 and 

Darlington, Maryland, on June 12, 2009, and conducted a site visit on June 10, 2009. The scoping 

meetings and site visit were noticed in a local newspaper and the Federal Register. The meetings were 

recorded and the transcript posted by the Commission on its Internet E-Library. 

The Commission requested that written comments on SD1 and Exelon’s Pre-Application Document 

(PAD) be provided to the Commission no later than July 10, 2009. In addition to the oral comments 

received during the scoping meetings, the Commission received 10 comment letters by the July 10 

deadline 7 . Thirteen of the letters provided comments on SD1 and 6 of the letters comment on the PAD. 

Table 1.4.1-1 lists Relicensing Participants that filed comments on SD1 and the PAD. 

Based on the Commission’s review of oral comments during the June 10 and 12 scoping meetings and 

written comments on SD1 and the PAD, on August 24, 2009, the Commission issued Scoping Document 

2 (SD2) that replaced SD1. 

1.4.2. Interventions 

At this time, the Commission has not acted on motions to intervene. 

1.4.3. Relicensing Studies 

1.4.3.1 FERC’s Determination on Revised Study Plan 

Pursuant to 18 C.F.R. § 5.11 of the Commission's regulations, Exelon filed its Proposed Study Plan (PSP) 

on August 24, 2009, and distributed the PSP to interested resource agencies and stakeholders for review 

and comment. In addition, pursuant to 18 C.F.R. § 5.11(e), Exelon held an initial meeting on the PSP at 

the Darlington Volunteer Fire Department in Darlington, MD on September 22 and 23, 2009. 

On November 20 and 23, 2009, several resource agencies and stakeholders provided comments on 

Exelon's PSP, pursuant to 18 C.F.R. § 5.12 of the Commission's regulations, including Commission staff, 

the PFBC, PGC, the Susquehanna River Basin Commission (SRBC) and USFWS. Exelon filed its 

7 The Mason-Dixon Trail System submitted comments on July 13, 2009, however this comment letter 

is included as being considered submitted by the comment period deadline. 

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Revised Study Plan (RSP) with FERC on December 22, 2009. Column A in Table 1.4.4-1 lists the 15 

studies included in Exelon’s RSP. 

On February 4, 2010, FERC issued a Study Plan Determination for Exelon’s Muddy Run Project. The 

Determination approved without modification 10 of the 15 studies in Exelon’s RSP, approved with 

modifications 5 of the studies, and did not add or eliminate any studies. On March 1, 2010, the Director 

issued an amendment to the study plan determination letter adding a radio-telemetry study to assess the 

potential for American eel entrainment at the Muddy Run Project. On June 17, 2010, FERC issued an 

Order Denying Rehearing on Exelon’s request to rehear the additional study ordered by FERC. 

1.4.3.2 FERC’s Determination Regarding Study Disputes 

Three agencies (SRBC, USFWS and PADEP) filed with FERC a formal dispute with FERC’s February 4, 

2010, Study Determination. Collectively, the agencies’ disputes focused on Study 3.3, Fish Entrainment 

and Impingement Assessment. 

On March 3, 2010, and May 20, 2010, FERC issued separate Orders Denying Rehearing to the SRBC, 

indicating that this federal agency does not have mandatory conditioning authority under Sections 4(e) or 

18 of the Federal Power Act, and denying SRBC’s request for rehearing of FERC’s study plan 

determination letters. 

On May 5, 2010, FERC issued a study dispute determination for the Muddy Run Project confirming that 

studies should be completed in accordance with their February 4 Study Plan Determination, as amended 

on March 1, 2010. Requests for rehearing by PADEP and the USFWS of this determination were denied 

by FERC in an Order Denying Rehearing dated July 15, 2010. 

1.4.3.3 FERC’s Determination on Initial Study Report 

Exelon filed with FERC an Initial Study Report on February 22, 2011, held an Initial Study Report 

meeting on March 9-11, 2011, and filed with FERC an Initial Study Report meeting summary on March 

28, 2011. Ten stakeholders filed letters regarding Exelon’s Initial Study Report with FERC. On June 24, 

2011, the Commission issued a Determination that did not require any modifications to studies. 

1.4.3.4 FERC’s Determination on Updated Study Report 

Exelon filed with FERC an Updated Study Report on January 23, 2012, and held an Updated Study 

Report meeting on February 1-2, 2012. Exelon filed an Updated Study Report meeting summary on 

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February 17, 2012. On May 21, 2012, the Commission issued a Determination that did not require any 

refinements to studies. 

1.4.3.5 Study Status 

All of the studies FERC has approved for the Project’s relicensing have been completed. Where 

applicable, the findings of these studies have been incorporated into the license application. 

1.4.4. Comments on the Draft License Application 

On April 3, 2012, Exelon filed with FERC and made available to Relicensing Participants a Draft License 

Application (DLA). 

Twelve letters regarding Exelon’s DLA were filed with FERC within the 90-day comment period, which 

ended on July 9, 2012. Table 1.4.4-1 lists the commenters and the date of their letter. 

TABLE 1.4.4-1. LIST OF COMMENT LETTERS FILED WITH FERC ON EXELON’S 

DRAFT LICENSE APPLICATION. 

Commenter Date of Letter 

Mason-Dixon Trail February 10, 2012 

FERC July 2, 2012 

PADEP July 2, 2012 

Rawlinsville Fire Department May 13, 2012 

MDNR July 9, 2012 

TNC July 9, 2012 

NMFS July 9, 2012 

NPS July 6, 2012 

PFBC July 9, 2012 

SRBC July 9, 2012 

USFWS July 5, 2012 

Susquehanna Riverkeeper July 8, 2012 

Exelon has addressed the various comment letters that were received on the DLA, consistent with the 

regulatory requirements of 18 CFR § 5 and the related FERC guidance. Refer to Appendix A of this 

Exhibit E for a reply to comments requesting additional studies of clarification of material in the DLA. 

Proposals regarding PM&E measures and studies that were not adopted by Exelon, and the reason Exelon 

did not adopt them, are discussed in Exelon’s response to comments on the DLA provided in Appendix A 

of Exhibit E. 

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1.4.5. Comments on the Final License Application 

Upon filing, FERC will solicit and compile comments on the final license application. Within 14 days of 

filing, FERC will issue a public Tendering Notice for the application which includes a schedule for 

processing of the application. When FERC determines the application is complete, it will then issue a 

Notice of Acceptance of the application and a Notice of Ready for Environmental Analysis (REA). 

Comments on this REA notice, intervention requests, and preliminary terms and conditions must be filed 

with FERC no more than 60 days after the REA notice has been issued. The licensee must also file a 

Water Quality Certificate Application within 60 days from the issuance of the REA notice. At this time, 

FERC will consider comments received and begin development of the NEPA document required for the 

licensing action. Once this process has been completed and a Water Quality Certificate has been issued, 

FERC will then issue a new license for the Project. 

1.4.6. Comments on the Draft Environmental Assessment 

FERC will solicit, compile and respond to comments received on the draft EA, or draft EIS if FERC 

chooses to prepare an EIS instead of an EA, in the final environmental document. 

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TABLE 1.4.1-1: SCOPING COMMENT SUMMARY 

Relicensing Participant Date of Letter 

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Document on Which Comments Were 

Filed 

FERC’s 

Scoping 

Document 1 

Exelon’s Pre- 

Application Document 

USFWS July 10, 2009 X X 

Susquehanna River Basin 

Commission 

July 10, 2009 X X 

PFBC July 10, 2009 X X 

PADEP July 10, 2009 X -- 

Nature Conservancy July 10, 2009 X -- 

NMFS July 10, 2009 X -- 

MDNR July 10, 2009 X -- 

Lower Susquehanna Riverkeeper July 10, 2009 X X 

Lancaster County Planning 

Commission 

July 10, 2009 X -- 

FERC July 10, 2009 X X 

American Rivers July 10, 2009 X --

Study 

Number 



TABLE 1.4.4-1: LICENSING STUDY SUMMARY 

Study Description 

Studies Proposed by 

Exelon in Exelon’s 

December 22, 2009 

Revised Study Plan 

3.1 Water Quality Study X X 

3.2 

3.3 

3.4 

3.5 

3.6 

3.7 

3.8 

3.9 

3.10 

3.11 

Hydrologic Study of Muddy 

Run Water Withdrawal and 

Return Characteristics 

Fish Entrainment and 

Impingement Assessment 

Impacts of Muddy Run Project 

on Conowingo Pond Fishes 

Nearfield Effects of the 

Muddy Run Project on 

Migratory Fishes 

Muddy Run Project Effects on 

Migratory Fishes: Interactions 

with the PBAPS Thermal 

Plume 

Transmission Line Avian 

Interaction Study 

Study to Identify Habitat Use 

Areas for Bald Eagle 

Study to Identify Potential 

Habitat and Presence/Absence 

of Bog Turtle and Rough 

Green Snake 

Creel Survey of Muddy Run 

Recreation Lake 

Recreational Inventory and 

Needs Assessment 

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X X 

Studies Approved or Modified 

by FERC in FERC’s February 

4, 2010 Determination 

Approved Modified 

X X X 

X X X 

X X X 

X X X 

X X 

X X 

X X 

X X X 

X X 

3.12 Shoreline Management Plan X X 

3.13 

3.14 

Visual and Noise Assessment 

of the Muddy Run Project 

Archaeological and Historic 

Cultural Resource Review and 

Assessment 

X X 

X X 

3.15 Osprey Nesting Survey X X

SECTION 2.0 



PROPOSED ACTION AND ALTERNATIVES 

This section describes the existing Project (i.e., the No-Action Alternative) and Exelon’s proposed 

changes to the existing Project (i.e., proposed Project). Specifically, Section 2.1 describes the No-Action 

Alternative, the baseline from which to compare all action alternatives. Section 2.2 describes Exelon’s 

proposed Project. Section 2.3 describes any other action alternatives proposed at this time. Section 2.4 

describes alternatives considered but not analyzed in detail in this document. 

2.1. No Action Alternative 

2.1.1. Existing Project Facilities 

The existing Project facilities consists of: 1) a main dam embankment, 2) the east dike, 3) recreation pond 

dam and spillway 4) canal dam embankment, 5) upper reservoir spillway 6), intake structure 7) a 

powerhouse and 8) a primary transmission line. The Project also includes public recreation facilities and 

use areas. The location of major Project facilities is shown in Figure 2.1.1-1. Detailed descriptions of 

these facilities are provided in Exhibit A of this application. The principal Project facilities as currently 

licensed are summarized below. 

� The main dam embankment is a rock-filled dam with a central impervious core approximately 

4,800 feet long, with a maximum height of 260 feet. The crest of the dam is at elevation 533 feet, 

is 34 feet wide and is traversed by a 20-foot-wide two-laned roadway (River Road). The main 

dam forms the Power Reservoir, which has a normal operating elevation range of 470 feet to 520 

feet. At elevation 520 feet, the Power Reservoir has a total storage capacity of 56,731 acre-feet 

with a usable capacity of 33,894 acre-feet, and a surface area of 892 acres. 

� The East Dike is approximately 800 feet long, has a crest width of 20 feet, and a maximum height 

of about 12 feet. The east dike is also a zoned earth and rock-fill embankment with an 

impervious core. The crest of the east dike is 530.8 feet. 

� The Recreation Pond Dam is a zoned earth and rockfill embankment, approximately 750 feet 

long, with a maximum height of about 90 feet and a crest width of 34 feet. The crest is at 

elevation 530. The recreation pond spillway consists of a nearly level rock cut channel 

approximately 140 feet wide with a concrete weir at crest elevation 520 feet. The dam forms a 

pond with a total storage capacity of 709 acre-feet, and surface area of approximately 100 acres at 

its constant elevation of 520 feet. 

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� The Canal Embankment forms the upper part of the intake channel which leads from the upper 

reservoir to the intake structure. The lower part of the channel is excavated in rock. The 

embankment has a maximum height of about 35 feet. The upstream face of the embankment and 

the rock cut channel are lined with a nine-inch-thick reinforced concrete slab extending about 

1,000 feet upstream on both sides of the canal from the cylinder gates. The upstream portion of 

the canal is an unlined soil and rock cut. 

� The spillway for the Power Reservoir is located on the west side of the intake canal. It is a 

concrete ogee type structure 200 feet long, 20 feet high, has a crest elevation of 521 feet and 

discharges into a vegetated natural ravine. 

� The Intake Structure consists of four cylinder gates with trash racks (clear spacing of 5.375 

inches). Each intake supplies two units and includes a cylindrical tower which leads to a 430- 

foot-deep vertical shaft. The vertical shafts and horizontal power tunnels are concrete lined with 

a diameter of 24.5 feet. The concrete lined power tunnels bifurcate approximately 500 feet 

upstream of the powerhouse, and transition to 14-foot-diameter steel penstocks that continue 

downstream to connect to one of eight pump turbine units in the powerhouse. 

� The powerhouse containing eight Francis-type pump-turbine/motor-generator units, each with a 

hydraulic capacity of 4,000 cubic feet per second (cfs) at a rated head of 412 feet, for a total 

discharge capacity from the powerhouse of 32,000 cfs. The pumping capacity of the pump 

turbines is 3,500 cfs each at a rated head of 427 feet, for a total powerhouse pumping capability 

of 28,000 cfs. The electrical generating equipment consists of eight motor-generator units, each 

rated at 13.8 kilovolts (kV). 

� The primary transmission lines within the Project boundary consist of two 230 kV three-phase, 

three-wire circuits. Both lines begin at a 230 kV switching station located on the roof of the 

Muddy Run Powerhouse and run approximately 4.25 miles to the PBAPS North Substation. 

2.1.2. Existing Project Boundary 

The Project boundary encompasses approximately 2,793 acres (Figure 2.1.2-1). There are approximately 

1,793 acres of land around the upper reservoir and a portion of the Susquehanna River shoreline on 

Conowingo Pond, where the Project powerhouse is located. The Project boundary also includes the 900- 

acre Muddy Run Power Reservoir and the 100-acre Recreation Lake. The lands for the Muddy Run 

E-17



Project are located within Lancaster and York Counties, Pennsylvania. The westerly portion of the 

Project boundary lies near Route 372 (Holtwood Road), while northerly and easterly portions lie near 

Susquehannock Road and Silver Spring/River Roads, respectively. The southerly portion of the Project 

boundary encompasses a steep bluff along the shoreline of the Susquehanna River from Route 372 

(Holtwood Road) downstream to Powerhouse Road, just southeast of Wissler’s Park. The Project 

boundary also includes a 4.25 mile transmission line corridor that crosses Conowingo Pond to the west 

shoreline, before turning south and continuing to PBAPS. 

2.1.3. Existing Project Safety 

The Project has been operating for more than 45 years under the existing license and during this time 

FERC staff has conducted operational inspections focusing on the continued safety of the structure, 

identification of unauthorized modifications, efficiency and safety of operations, compliance with the 

terms of the license, and proper maintenance. In addition, the Project has been inspected and evaluated 

every 5 years by an independent consultant and a consultant’s safety report has been submitted for 

FERC’s review. 

2.1.4. Existing Project Operations 

The Muddy Run Project is a pumped storage hydroelectric facility. Water is pumped from the lower 

reservoir (Conowingo Pond) to the upper reservoir which has 33,894 acre-feet of active storage available 

for pump storage operations. Typically, pumping occurs during low-load periods when energy costs are 

low, while generation occurs during high-load periods. 

2.1.5. Existing Environmental Measures and Recreation Facilities 

The Project includes a wildlife management area (WMA) located along the northerly, westerly and 

southerly portion of the Muddy Run Project’s Power Reservoir. The Muddy Run WMA consists of 

approximately 800 acres (Project and non-Project land) owned by Exelon and leased to (and managed by) 

the PGC. The land is managed to provide food and cover for wildlife. A series of management roads and 

trails provide access for hunters, hikers, birders, and equestrians. Exelon also maintains a series of 

recreational facilities with the Project Boundary. The facilities are described briefly below; more detailed 

descriptions are contained in Section 3.3.6. 

E-18

Muddy Run Park 



Muddy Run Park encompasses approximately 700 acres of Project lands and also includes the 100 acre 

recreation lake on the northerly end of the Muddy Run Project Power Reservoir. The park is owned by 

Exelon and operated by a vendor. 

The developed portion of the park is located on the west side of the recreation lake and provides both 

overnight and day use facilities. A 189 site campground (148 trailer sites with electric and water hookup, 

38 tent sites and three primitive group sites) with two dumping stations, two comfort stations , shower and 

laundry facilities, two playgrounds, and a covered picnic pavilion is located on the northerly shoreline of 

the recreation lake. There is also a large area on the east shore of the recreation lake that is occasionally 

used for camping and special events. Numerous separate facilities are located throughout the park, 

including a day use area with two covered pavilions, two restroom facilities, a boat launch with dock, four 

playgrounds, an outdoor amphitheater, a basketball court, a ball field, a tractor pull area, and picnic tables 

and grills. A non-motorized trail extends around the perimeter of the recreation lake (approximately 3.5 

miles) and several side trails branch off the trail for access to the pond for fishing. 

Boat rentals (canoes, kayaks, paddleboats, rowboats) are available at the park and visitors can launch their 

own boats (launch fee required) at the park boat ramp. The boat ramp provides launch opportunities for 

small boats on the recreation lake. Gasoline powered boats are not allowed on the recreation lake, though 

electric motors are allowed. Swimming is not allowed in the recreation lake. 

A visitor’s information center contains displays and meeting rooms. The center is also used for park 

related programs and rental functions. 

Wissler’s Run Park 

Wissler’s Run Park is located on the east bank of the Susquehanna River immediately downstream of the 

Muddy Run Project Powerhouse. The park is owned and managed by Exelon and provides a large open 

green space area for picnicking, bank fishing, and an overlook of the upper Conowingo Pond and islands. 

Improvements at the site include a covered pavilion with picnic tables, benches, an informational kiosk, a 

450 foot long paved pathway along the river bank for angler access, a 12’ by 15’ fish cleaning facility 

(non-functioning ) , and an ADA portable restroom. A paved 130 space parking lot services this site. 

E-19



2.2. Exelon’s Proposal 

2.2.1. Proposed Project Facilities 

2.2.1.1 Generation Facilities 

Exelon does not propose any changes to existing developmental (i.e., generation) facilities. 

2.2.1.2 Non-Generation Facilities 

Exelon has proposed the following capital improvements to recreation facilities at the Muddy Run 

Project. 

Shoreline Improvements at the Recreation Lake 

The existing boat launch facility will be replaced with a new concrete plank ramp with a new gangway 

and floating dock. The ramp is sized for launching small trailered watercraft suitable for boating on the 

recreation lake (electric motors only). The ramp will be 12 feet wide and of a length to provide a water 

depth of three feet at the toe of the ramp. Docking will consist of a concrete gangway abutment, three 

foot wide gangway, and an 80 inch wide dock of sufficient length. The gangway and dock will be 

Americans with Disabilities Act (ADA) compliant. A small ADA picnic area adjacent to the boat launch 

facility will be upgraded to improve the stability and firmness of the surface and drainage. Renovations 

to this area will enhance access and reduce future maintenance to this site. Approximately 150 feet of 

shoreline between the ADA picnic area and the rental boat dock will be improved to control run-off and 

potential erosion into the recreation lake. This will be accomplished by removing the boulders from the 

area, re-grading, applying a crushed gravel base to prevent further shoreline erosion. The existing timber 

retaining wall along the shoreline at the rental boat dock area will be removed and replaced with a sheet 

pile retaining wall. A new ADA gangway and floating dock will also be installed. The retaining wall is 

being replaced as the existing wall is being undermined by the action of the lake. 

Muddy Run Park Campground 

The campground includes 148 camper trailer sites with water and electric hook-ups. Presently, 137 of 

these sites have 30 amp electric hook-ups. Eleven sites with 50 amp hook-ups were upgraded within the 

past three years to accommodate newer camper trailers that are wired for 50 amp service. The demand 

for 50 amp campsites exceeds the current supply of such sites. Exelon will upgrade the electric service to 

an additional 50 campsites, and monitor future need and upgrade additional sites when the demand exists. 

E-20



Other Muddy Run Park Enhancements 

Exelon will expand an existing playground area near the Visitor’s Center with safety swings and three 

modular play structures suitable for younger children (“tot lot”). A mulch safety surface will also be 

installed. A 2,000 square foot water spray park will be constructed near the Park entrance. Also, the 

existing paving will be resurfaced. 

Wissler’s Park. Some facilities at Wissler’s Park have recently been renovated to improve their 

condition. This includes the paved walkway from the parking area to the picnic pavilion. The parking lot 

was repaved in 2011. Currently, the pavilion is being replaced. Exelon plans to designate and sign two 

additional ADA parking spaces near the picnic pavilion for compliance with standards set by 

Accessibility Guidelines for Buildings and Facilities (ADAAG). A non-functioning fish cleaning station 

will be demolished and the site reclaimed. 

Wildlife Management Area. Pursuant to license Article 41, Exelon leases lands to the PGC, which is 

managed to provide food and cover plantings for wildlife, and provide public hunting opportunities. 

Exelon proposes to continue this arrangement with PGC for the term of a new FERC license. Exelon will 

erect and maintain FERC Part 8 signs at the River Road and Furniss Road WMA parking areas to identify 

the conditions of access to the site. 

2.2.2. Proposed Project Boundary 

Exelon is not currently proposing any changes to the existing Project boundary. 

2.2.3. Proposed Project Safety 

Exelon anticipates that, as part of the relicensing process, FERC staff will evaluate the continued 

adequacy of the proposed Project facilities under the new license. FERC will include special conditions 

in the new license, as appropriate. Exelon anticipates FERC will continue to inspect the Project during 

the new license term to assure continued adherence to FERC-approved plans and specifications, special 

license articles pertaining to construction if any is proposed, operations and maintenance, and accepted 

engineering practices and procedures. 

2.2.4. Proposed Project Operations 

Exelon is not currently proposing any changes to the existing Project operations. 

E-21



2.2.5. Proposed Environmental Measures 

Exelon proposes to continue existing environmental measures described in Section 2.1.5. In addition, the 

Exelon proposes a series of additional measures to protect and enhance resources in the Project Boundary 

during the term of the next license. The proposed measures are summarized below. 

Shoreline Management Plan 

Exelon proposes to implement a Shoreline Management Plan (SMP) consistent with Guidance for 

Shoreline Management Planning at Hydropower Projects (FERC 2001). The SMP includes specific 

measures and policies related to shoreline vegetation management and erosion control, woody debris 

management, game species management, sensitive natural resource protection, recreation use, and use of 

Project lands. Exelon proposes to adopt best management practices for controlling sediment introduction 

from lands within the Project boundary. The SMP is being filed in Volume 3 of this license application. 

Bog Turtle Management Plan 

Due to the presence of bog turtles within the Project boundary, Exelon has developed a Bog Turtle 

Management Plan (BTMP) in consultation with the USFWS and the PFBC. This management plan entails 

three components. 

� Restriction of mowing in the wetland documented to support bog turtles. 

� Invasive plant and woody plant control, particularly for reed canary grass. 

� Limits on public access to the wetland without advertising the reason. 

The BTMP is being filed in Volume 4 of this license application. 

Bald Eagle Management Plan 

Bald eagles use Project lands and waters for nesting, roosting and foraging. Exelon has developed a Bald 

Eagle Management Plan (BEMP) in consultation with the USFWS and PGC. 

The BEMP provides for the management of bald eagle habitat on Exelon lands in accordance with 

recommendations from the National Bald Eagle Management Guidelines and state agency guidance. Bald 

eagle habitat, including nest sites, forage sites, and communal roost sites on Exelon lands will be 

managed through a range of measures. The range of measures is tailored to types of activities with 

potential to impact eagles and will include, but not be limited to, seasonal restrictions, distance buffers, 

and landscape buffers. The BEMP is being filed in Volume 4 of this license application. 

E-22



Historic Properties Management Plan 

If necessary, Exelon will implement an HPMP for the management of archaeological and historic 

resources throughout the term of the new license. The HPMP will be prepared in consultation with the 

Pennsylvania SHPO, and other stakeholders and in accordance with the Guidelines for the Development 

of Historic Properties Management Plans for FERC Hydroelectric Projects. 

The HPMP will address, among other things, a schedule and methodology for implementing monitoring 

measures; management measures for identified historic properties; protection of historic properties 

threatened by Project-related activities, including Project operations, shoreline and aquatic recreation, 

shoreline development, routine Project maintenance, and other Project activities or operations; and public 

outreach, education, and signage for the purpose of reducing looting and vandalism of sites. 

Recreation Management Plan 

Exelon proposes to implement a Recreation Management Plan (RMP). The RMP will guide the operation 

and maintenance of Exelon’s recreation facilities, and also include proposals for recreation facility 

enhancements outlined above in Section 2.2.1.2. The RMP is being filed in Volume 3 of this license 

application. 

2.3. Alternatives Considered But Eliminated From Further Analysis 

Exelon considered but eliminated from further analysis the following alternatives: 

� Retire the Project 

� Issue a Non-Power License 

� Federal Agency Takeover of the Project 

Each of these alternatives and the consideration of factors through which the alternative was eliminated 

from further analysis are described below. 

2.3.1. Retire the Project 

Project retirement could be accomplished with or without removal of the Project dams. No relicensing 

participant has suggested that removal of the Project dams would be appropriate in this case; therefore, 

there is no basis for recommending it. Thus, dam removal is not a reasonably foreseeable alternative to 

relicensing the Project with appropriate resource management measures. 

E-23



The second Project retirement alternative would involve retaining the Project dams and disabling or 

removing equipment used to generate power. Project works would remain in place and could be used for 

historic, consumptive, environmental and recreational water management, or other purposes. This would 

require that a government agency with authority to assume regulatory control and supervision of the 

remaining facilities be identified. No relicensing participant has advocated this alternative. Therefore, 

there is no basis for recommending it. Because the power supplied by the Project is needed, a source of 

replacement power would have to be identified. In these circumstances, removal of the electric 

generating equipment is not a reasonably foreseeable alternative. 

FERC’s statement from SD2 regarding a project decommissioning license analysis follows: 

Decommissioning of the Project could be accomplished with or without dam removal. Either 

alternative would require denying the relicense application and surrender or termination of the 

existing license with appropriate conditions. There would be significant costs involved with 

decommissioning the Project and/or removing any Project facilities. The Project provides a viable, 

safe, and clean renewable source of power to the region. With decommissioning, the Project would no 

longer be authorized to generate power. 

No party has suggested Project decommissioning would be appropriate in this case, and we have no 

basis for recommending it. Thus, we do not consider Project decommissioning a reasonable 

alternative to relicensing the Project with appropriate environmental enhancement measures. 

2.3.2. Issue a Non-Power License 

A non-power license is a temporary license that FERC issues when it determines that a project should no 

longer be used for power purposes. Such licenses are designed as an interim measure until a separate 

state, municipal, interstate, or federal agency assumes regulatory supervision over the lands and facilities 

involved. FERC’s statement from SD2 regarding a non-power license analysis follows: 

A non-power license is a temporary license which the Commission would terminate whenever it 

determines that another governmental agency will assume regulatory authority and supervision over 

the lands and facilities covered by the non-power license. 

Hence, issuing a non-power license for the Project would not provide a long-term solution to the 

issues presented. To date, no party has sought a non-power license, and we have no basis for 

concluding that the Project should no longer be used to produce power. Thus, we do not consider a 

E-24



non-power license to be a reasonable alternative to some form of new license with enhancement 

measures. 

Because the Project power is needed and Exelon believes that a new license can be issued that will satisfy 

the FPA’s public interest/comprehensive development standard, Exelon believes there is no basis for the 

Commission to conclude that the Muddy Run Project should no longer be used for power generation. 

Thus, issuance of a non-power license is not a reasonable alternative to issuance of a new license with 

appropriate PM&E measures. 

2.3.3. Federal Agency Takeover of the Project 

Federal takeover of the Project is not a reasonably foreseeable alternative. Federal takeover and operation 

of the Project would require federal Congressional approval. While that fact alone would not preclude 

further consideration of this alternative, there is no evidence to indicate that federal takeover should be 

recommended to Congress. No relicensing participant or other party has suggested federal takeover 

would be appropriate, and no federal agency has expressed an interest in operating the Project. 

FERC’s statement from SD2 regarding a federal government takeover license analysis follows: 

In accordance with § 16.14 of the Commission’s regulations, a federal department or agency may file 

a recommendation that the United States exercise its right to take over a hydroelectric power project 

with a license that is subject to sections 14 and 15 of the FPA (16 U.S.C. §§ 791(a)-825(r). We do 

not consider federal takeover to be a reasonable alternative. Federal takeover of the Project would 

require congressional approval. While that fact alone would not preclude further consideration of this 

alternative, there is currently no evidence showing that federal takeover should be recommended to 

Congress. No party has suggested that federal takeover would be appropriate and no federal agency 

has expressed interest in operating either of the projects. 

Federal takeover of the Project is not a reasonably foreseeable alternative. 

E-25

SECTION 3.0 



ENVIRONMENTAL ANALYSIS 

3.1. General Description of the River Basin 

The Susquehanna River originates near Cooperstown, New York at Otsego Lake and flows for about 444 

miles to the Chesapeake Bay at Havre de Grace, Maryland (SRBC 2008a) (Figure 3.1-1). The drainage 

area of the Susquehanna River encompasses portions of New York, Pennsylvania and Maryland and 

covers 27,510 square miles. The Susquehanna River Basin can be divided into six major subbasins: the 

Upper Susquehanna, Chemung, West Branch Susquehanna, Middle Susquehanna, Juniata, and Lower 

Susquehanna. The Muddy Run Project is located on Muddy Run, a tributary (at River Mile 22) to the 

Lower Susquehanna River. The Muddy Run drainage area above the Muddy Run Main Dam is 9.2 

square miles. 

The Conowingo Hydroelectric Project (Conowingo Project) is located on the main stem of the Lower 

Susquehanna River, within the Lower Susquehanna subbasin, at River Mile (RM) 10 in Maryland. The 

main stem flows 130 miles through the subbasin and the impoundment formed upstream of the 

Conowingo Project extends approximately 14 miles. The Muddy Run Project utilizes Conowingo Pond 

on the mainstem Susquehanna River at its lower reservoir. Table 3.1-1 provides the drainage area, 

acreages and population within each subbasin. 

3.1.1. Topography 

The Muddy Run Project is located in the Piedmont Upland Section of the Piedmont Physiographic 

Province of Pennsylvania. The region is characterized by a rolling upland with broad hills and some 

steep-sided valleys (Risser and Siwiec 1996). The Susquehanna River valley narrows and deepens 

abruptly to a steep-walled gorge nearly 600 feet deep flanked by gently-rolling upland with under 100 feet 

of local relief as the river enters the Upland Section (Pazzaglia and Gardner 1993). This gorge is also 

called the Holtwood Gorge. 

The Muddy Run Project is located on Muddy Run, a tributary (at RM 22) to the Lower Susquehanna 

River. Muddy Run is a tributary of the Susquehanna River. The Muddy Run drainage area above the 

Muddy Run Main Dam is 9.2 square miles. The Muddy Run Reservoir is an impoundment created by the 

construction of the Muddy Run Main Dam, the Muddy Run Canal and the East Dike. Muddy Run 

Recreation Lake was created by impounding the upper reaches of the reservoir. The result was the 

flooding and permanent inundation of the lower lying areas surrounding the original course of Muddy 

E-28



Run. The upland elevations of the margins of this portion of the Muddy Run Project area reach elevations 

ranging 600 to 700 feet National Geodetic Vertical Datum of 1929 (NGVD 1929). 

The maximum elevation of the Muddy Run Power Reservoir is elevation 520 feet NGVD 1929, or 

approximately 411 feet above the normal pool level of Conowingo Pond. The top of the wall protecting 

the Muddy Run Powerhouse from the Susquehanna River is about elevation 135 feet NGVD 1929, or 

about 26 feet above the normal pool level of the Conowingo Pond. The transmission line corridor of the 

Muddy Run Project crosses Holtwood Gorge as it leaves the powerhouse. The transmission line traverses 

over a rolling topography which reaches a maximum of 500 to 510 feet NGVD 1929 about 1,200 feet 

south of Muddy Creek. 

The distinctive topography and landforms characterizing the Project area developed from the weathering 

and erosion of underlying geologic units described in the next section. 

3.1.2. Climate 

Climatic conditions vary within the Lower Susquehanna River subbasin. The Ridge and Valley 

physiographic province in the northwest experiences a humid continental climate with large seasonal 

temperature variations in contrast to the more coastal-type climate experienced in the Piedmont 

physiographic province in the southeastern part of the subbasin where temperatures are more moderate 

and precipitation is slightly greater (Risser and Siwiec 1996). 

Average annual precipitation is distributed fairly evenly throughout the year; however, long-term records 

indicate wet and dry periods (Risser and Siwiec 1996). Droughts have been fairly common, at times 

threatening groundwater supplies (SRBC 2005). During the 1990s through the mid-2000s droughts have 

occurred in 1991, 1995, 1997, 1998, 1999, 2000, 2002 and 2006 (SRBC 2007b). 

3.1.3. Land and Water Use 

3.1.3.1 Major Land Uses 

The Lower Susquehanna subbasin drains 5,809 square miles from Sunbury, Pennsylvania to Havre de 

Grace, Maryland (SRBC 2008b). Two-hundred eighty square miles are in Maryland. It is the most 

developed of the six subbasins. Some of the most productive agricultural lands and largest population 

centers of the Susquehanna River Basin are located in the Lower Susquehanna subbasin as well. Major 

population centers include Harrisburg (47,196), Lancaster (54,672), and York (40,226), Pennsylvania 

(2007 population estimates) (U.S. Census Bureau 2008). 

E-29



The Chesapeake Bay Watershed Land Cover Data Series (USGS 2006) indicates land cover of the Lower 

Susquehanna subbasin consists of forested areas (43.6 percent), pasture/hay (13.8 percent), cultivated 

crops (27.8 percent), developed (11.0 percent), open water and wetlands (2.8 percent), herbaceous 

grassland (0.5 percent) and barren land (0.4 percent). The land uses currently found near the Muddy Run 

Project are largely related to electric power production facilities and various recreation amenities. 

3.1.3.2 Major Water Uses 

Power generation (12 major power plants 8 ) accounts for the greatest water use in the Lower Susquehanna 

River subbasin (89 percent) (SRBC 2008b) Other uses are industrial (4.8 percent), municipal (4.2 

percent), agricultural (1.2 percent), and domestic (0.8 percent). The power producers use surface water 

while non-power users also rely on groundwater (Risser and Siwiec 1996). Seventy-eight percent of the 

approved consumptive water use in the entire basin (about 441 million gallons per day (MGD)) is from 

the Lower Susquehanna subbasin (SRBC 2008c) 9 . 

In its analysis of power plant water use in the entire basin, SRBC reports only 4 percent (168 million 

gallons per day (MGD)) of the water withdrawn from the basin by the fossil (8) and nuclear (3) power 

plants in Pennsylvania (4,217 MGD) is consumptively used (SRBC 2008d). This large percentage with 

respect to the rest of the basin is due to consumptive use (CU) by the City of Baltimore and Chester Water 

Authority diversions (100 percent CU) and the two nuclear power plants located within the lower 

subbasin (SRBC 2008c). SRBC also estimates that 785 agricultural operations consumptively use more 

than 20,000 gallons per day each across the entire basin (SRBC 2007a). Hydroelectric power generation 

is an in-stream non-consumptive use of water while thermoelectric power generation is a consumptive 

off-stream water use (Ludlow and Gast 2000). 

The Conowingo Project, located in Maryland, creates the Conowingo Pond, a 14-mile-long 9,000-acre 

pond, extending into Pennsylvania, with 35 miles of shoreline, a width varying from 0.5 to 1.3 miles, and 

a maximum depth of about 98 feet (SRBC 2006a). The Conowingo Pond is currently a source of water 

for: 

� Conowingo Hydroelectric Project, located in Cecil and Harford Counties, Maryland; 

� Muddy Run Project, Lancaster County, Pennsylvania; 

8 Five fossil, five hydro, and two nuclear (SRBC 2008d). 

9 2005 data 

E-30



� Peach Bottom Atomic Power Station, York County, Pennsylvania; 

� York Energy Center, York County, Pennsylvania; 10 

� City of Baltimore, Maryland, municipal water supply; 

� Harford County, Maryland, public water supply (provided by Baltimore’s system); 

� Chester Water Authority water supply utility, serving areas of southeast Pennsylvania and 

northern Delaware; 

� Recreational uses, including boating and fishing; and 

� Sustained stream flows downstream of the dam. 

3.1.3.3 Basin Dams and other Energy Producers 

Five projects cross the main stem of the Susquehanna River in the lower subbasin. These consist of four 

hydroelectric dams (Conowingo, Holtwood, Safe Harbor, and York Haven) and the Adam T. Bower 

Memorial Dam (the Sunbury fabridam). On Muddy Run, a tributary to the Lower Susquehanna River, 

there are four dams associated with the Muddy Run Project: the Main Dam, East Dike, Intake Channel 

Dam, and Recreation Dam. Nearly 300 smaller dams are also distributed throughout the Lower 

Susquehanna subbasin (H. Weinberger, Chesapeake Bay Program, personal communication, 2012) 

(Figure 3.1.3.3-1). 

Ten dam structures related to hydropower production are located within the Lower Susquehanna subbasin 

(Table 3.1.3.3-1). Three of these dams (Conowingo Dam, Holtwood Dam, and Safe Harbor Dam) form a 

reservoir system (Conowingo Pond, Lake Aldred, and Lake Clarke, respectively). Upstream of these 

reservoirs are the York Haven dams. The Muddy Run Project Main Dam crosses the Muddy Run ravine a 

few miles below Holtwood. The Muddy Run Project pumps water from a lower reservoir (Conowingo 

Pond) to an upper reservoir (Muddy Run Reservoir) formed by the Main Dam. 

3.1.3.4 Tributary Streams 

There are 21 major tributaries to the Susquehanna River (each with a drainage area of greater than 100 

square miles) in the lower subbasin (Risser and Siwiec 1996). These tributaries are listed in Table 3.1.3.4- 

1 and depicted in Figure 3.1.3.4-1. 

Muddy Creek is a major tributary to the Conowingo Pond. Smaller named tributaries to the Conowingo 

Pond include Conowingo Creek, Broad Creek, Hanes Branch, Michaels Run, Peters Creek, Barnes Run, 

Fishing Creek, Wissler Run, and Muddy Run. Numerous unnamed tributaries also discharge to 

10 Commercial operation began March 2011. 

E-31



Conowingo Pond. The major tributaries of the Conowingo Project below the Conowingo Dam are 

Octoraro Creek and Deer Creek. 

E-32



TABLE 3.1-1: CHARACTERISTICS OF THE SUSQUEHANNA RIVER SUBBASINS 

Subbasin Drainage Area 

(square miles) 

E-33 

Population 

Upper Susquehanna 4,944 488,800 

Chemung 2,595 225,350 

West Branch Susquehanna 6,978 475,350 

Middle Susquehanna 3,771 696,800 

Juniata 3,404 312,750 

Lower Susquehanna 5,809 1,761,500 

(Source: SRBC 2008b)

1 FERC (2004) 

2 USACE (2005) 



TABLE 3.1.3.3-1: HYDROPOWER IN THE LOWER SUSQUEHANNA RIVER SUBBASIN 

Project Dams River (River Mile) 1 NID ID 2 NID 

Height 

(feet) 2 

3 Susquehanna Electric Co (2005) 

E-34 

NID 

Length 

(feet) 2 

NID 

Storage 

(acre-feet) 2 

Nameplate 

Capacity 

(megawatts) 1 

Conowingo Susquehanna (10) MD00097 94 4,648 310,000 573 

Muddy Run Main Dam Muddy Run (22) 3 PA00266 260 4,800 56,731 800 

Muddy Run Intake 

Channel Dam (Canal 

Dam) 

Muddy Run Recreation 

Dam 

Muddy Run (NA) PA83008 35 2,300 56,731 NA 

Muddy Run (NA) PA83009 90 750 709 NA 

Muddy Run East Dike Muddy Run (NA) PA83010 12 800 56,731 NA 

Holtwood Susquehanna (24.6) PA00854 55 3,075 19,000 196 

Safe Harbor Susquehanna (32.2) PA00855 75 4,869 144,000 417 

York Haven Main Dam Susquehanna (56.1) PA00515 23 7,970 13,300 19 

York Haven East 

Channel Dam 

Susquehanna (NA) PA83001 10 935 13,300 NA 

York Haven Headrace Susquehanna(NA) PA83004 28 3,500 13,300 NA



TABLE 3.1.3.4-1: MAJOR TRIBUTARIES TO THE LOWER SUSQUEHANNA RIVER 

TRIBUTARY DRAINAGE AREA 

(SQUARE MILES) 

E-35 

STATE PHYSIOGRAPHIC 

PROVINCE 

Shamokin Creek 137 PA Ridge and Valley 

Middle Creek 175 PA Ridge and Valley 

Penns Creek 533 PA Ridge and Valley 

Mahanoy Creek 157 PA Ridge and Valley 

Mahantango Creek 164 PA Ridge and Valley 

Wiconisco Creek 116 PA Ridge and Valley 

Sherman Creek 244 PA Ridge and Valley 

Conodoguinet Creek 506 PA Ridge and Valley 

Yellow Breeches Creek 219 PA Ridge and Valley 

Swatara Creek 571 PA Ridge and Valley 

Bermudian Creek 110 PA Piedmont 

Conewago Creek 515 PA Piedmont 

South Branch Codorus Creek 117 PA Piedmont 

Codorus Creek 278 PA Piedmont 

Chickies Creek 126 PA Piedmont 

Cocalico Creek 140 PA Piedmont 

Conestoga River 277 PA Piedmont 

Pequea Creek 154 PA Piedmont 

Muddy Creek 139 PA Piedmont 

Octoraro Creek 210 MD & PA Piedmont 

Deer Creek 170 MD & PA Piedmont 

(Source: Risser and Siwiec 1996)



3.2. Cumulative Effects Analysis 

3.2.1. Cumulatively Affected Resources 

According to § 1508.7 of the Council on Environmental Quality’s regulations for implementing NEPA, 

an action may cause cumulative impacts on the environment if its impacts overlap in space and time with 

the impacts of other past, present and reasonably foreseeable future actions regardless of what agency or 

person undertakes such other actions. Cumulative effects can result from individually minor but 

collectively significant actions taking place over a period of time, including hydropower and other land 

and water development activities. 

This Exhibit E addresses four resource areas that have a potential to be cumulatively affected by the 

continued operation of the Project in combination with other activities: 

� Geology and Soils 

� Water Quantity and Quality 

� Aquatic Resources 

� Threatened and Endangered Species 

Provided below is the geographic and temporal scope of the cumulative affects analysis for these 

resources, and past, present and reasonably foreseeable future actions considered in the analysis. 

3.2.2. Geographic Scope of Analysis for Cumulatively Affected Resources 

The geographic scope of the cumulative effects analysis defines the physical limits or boundaries of the 

proposed action’s effect on the resources. Because the proposed action would affect the resources 

differently, the geographic scope for each resource may vary. FERC’s SD2 described the geographic 

scope for cumulative effects as follows: 

“Based on information in the Conowingo and Muddy Run PADs and preliminary staff analysis, 

we have identified water quality and quantity, resident and diadromous fish, and Chesapeake Bay 

habitats as resources that may be cumulatively affected by the proposed operation of the projects 

in combination with other developmental activities in the Susquehanna River Basin.” 

Exelon has included this geographic area to the cumulative effects analysis for the resources identified by 

FERC. 

E-39



3.2.3. Temporal Scope of Analysis for Cumulatively Affected Resources 

The temporal scope of the cumulative effects analysis addresses past, present, and future actions and their 

effects on each affected resource. Based on the expected term of a new license, the temporal scope of 

analysis addresses reasonably foreseeable actions for 30-50 years into the future. 

3.2.4. Past, Present and Reasonably Foreseeable Future Actions 

The cumulative effects of past and present actions on water quantity and aquatic resources are 

incorporated into the description of the existing resources in Sections 3.3.1, 3.3.2, 3.3.3, and 3.3.5 of this 

Exhibit E. 

3.3. Proposed Action and Action Alternative 

3.3.1. Geology and Soils 

3.3.1.1 Affected Environment 

3.3.1.1.1 Geology 

The Muddy Run Project is located in the Piedmont Upland Section of the Piedmont Physiographic 

Province of Pennsylvania. The Piedmont Upland Section contains crystalline bedrock (low-grade 

metamorphic rocks and metamorphosed igneous rocks) with a mantle of unconsolidated in situ or 

transported surficial material. The underlying geologic structure is the result of multiple episodes of 

metamorphism and deformation. The Pennsylvania Geological Survey (PGS) and United States 

Geological Survey (USGS) each use different rock unit terms to represent different levels of detail of 

geologic mapping in different regions. The bedrock geology described in this report is based on the 

digitally updated 1980 Geologic Map of Pennsylvania (PGS 2001) depicted on a digital map compiled by 

the Susquehanna River Basin Commission (SRBC 2006b). 

3.3.1.1.2 Bedrock Geology 

The bedrock geology of the Project area is illustrated in Figure 3.3.1.1-1 and described in Table 3.3.1.1.2- 

1. 

The Muddy Run Reservoir in Lancaster County and the surrounding area are underlain with the Octoraro 

Formation (Xo). In York County, north of Muddy Creek, the transmission line connecting the Muddy 

Run powerhouse with the regional transmission grid near Peach Bottom Atomic Power Station is also 

underlain with the Octoraro Formation. After crossing Muddy Creek in a southern direction, the 

transmission line corridor is, for the most part, underlain with the Peters Creek Schist (Xpc). About 4,000 

E-40



feet south of Muddy Creek the transmission line crosses ultamafic rocks consisting primarily of 

serpentinite (Xu). 

Outcropping bedrock islands in the Susquehanna River from below Holtwood Dam to Mt. Johnson 

Island, collectively called the Conowingo Islands, are recognized as an outstanding geologic feature of 

Pennsylvania (Geyer and Bolles 1979). Most of the islands are concentrated between Holtwood Dam and 

Muddy Creek. This area of the Susquehanna River is also known as the Holtwood Gorge. The potholes 

and cliffs of the gorge area are regarded by the PADCNR as heritage geology sites called Erosional 

Remnants. The gorge contains three distinct bedrock terraces representing episodes of rapid downcutting 

that took place about 13,000 to 35,000 years ago (Reusser et al. 2004). After leaving the powerhouse, the 

transmission line crosses three of the Conowingo Islands: Turkey Island, an unnamed island, and Lower 

Bear Island. 

3.3.1.1.3 Surficial Geology 

Surficial geologic units overlap with the United States Department of Agriculture (USDA) Natural 

Resources Conservation Service (NRCS) soils series that are described in the next section. Descriptions 

of surficial geologic units provide information not available in USDA/NCRS soil descriptions. 

Surficial geologic units within the Project area form a discontinuous mantle of unconsolidated in situ 

material (weathered bedrock and saprolite) and transported material (alluvium and colluvium) (Sevon 

1996). Weathered bedrock consists of all in situ rock between the surface and unweathered rock at depth 

that is broken or breaks readily with minimal force. Saprolite is weathered bedrock that is typically soft, 

easily cut with a knife or dug with a shovel. Alluvium is material transported and deposited by running 

water. Colluvium is material mass transported by gravity. 

Some of this material is deposited on lower terraces located within about 150 feet above the present 

channel along the margins of the Conowingo Pond and Susquehanna River and at major tributary mouths 

throughout the Project area, and on upland terraces located about 260 and 460 feet above the present 

channel (Pazzaglia and Gardner 1993). The transmission line corridor crosses these features. 

The transmission line corridor crosses Holtwood Gorge. Surficial geologic features characteristic of the 

gorge are the exposed bedrock islands, large rounded boulders scattered on the islands, and very deep 

potholes (Thompson 1990). Along the eastern wall of the gorge, unconnected and elongate, spoon- 

shaped “deeps” over 3,000 feet in length, about 300 feet across, and up to 115 feet deep occur (Pazzaglia 

E-41



and Gardner 1993). The gorge contains three distinct bedrock terraces representing episodes of rapid 

downcutting that took place about 13,000 to 35,000 years ago (Reusser et al. 2004) 

The different surficial units mapped in the Project area by Sevon (1996) are described in Table 3.3.1.1.3- 

1. Saprolite is restricted to the edge of the Project area boundary about 1,500 feet south of Muddy Run 

west of Susquehannock Drive. 

3.3.1.1.4 Soils 

The most up-to-date soils mapping and map unit descriptions available were accessed from the Soil 

Survey Geographic database (SSURGO) (Figure 3.3.1.1.4-1 and 3.3.1.1.4-2). Map units may represent 

more than one soil series and map unit symbols for the same unit in the two counties may be different. 

The Muddy Run Reservoir portion of the Project area is covered primarily with Chester, Glenelg, and 

Manor soils that developed from weathered bedrock. These map units are non-hydric. The Baile silt 

loam, a hydric soil mapped only in one of the unnamed tributaries of Muddy Run Reservoir, may also 

occur as hydric inclusions in Chester and Glenville soils. The hydric Holly silt loam may also be present 

as inclusions in some soil map units. Hydric soils form under conditions that promote the development of 

wetlands. The soils traversed along the transmission line corridor are primarily Manor and Mt. Airy soils 

that developed from weathered bedrock on steep slopes. 

The soil map units within the Project area are described in Tables 3.3.1.1.4-1 and 3.3.1.1.4-2. 

3.3.1.1.5 Shoreline Characteristics 

The Muddy Run Reservoir shoreline is a wide and gently sloping non-vegetated zone that is alternately 

exposed and inundated (the shore zone). The shore zone is primarily unweathered bedrock covered with a 

veneer of fragmented weathered bedrock, colluvium and alluvium (Figure 3.3.1.1.5-1). Bedrock often 

crops out as steeply dipping protrusions or is exposed as massive cliffs (Figure 3.3.1.1.5-2) and in situ 

tree stumps are common (Figure 3.3.1.1.5-3). Where tributaries enter the reservoir, meandering 

thalwegs 11 traverse alluvium within broad swale morphology (Figure 3.3.1.1.5-4). Gullies, rills, and sheet 

11 The thalweg of a channel is a line of maximum depth along the bed. In streams with great water level fluctuations, 

the thalweg may be evident as a very narrow water-filled channel within a wide aerially exposed channel bed during 

the lowest water levels. 

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flow features on exposed shores drain surrounding riparian areas and some may be fed by groundwater 

seeps. 

3.3.1.1.6 Shoreline Types 

Near-vertical bedrock outcrops occur at the water’s edge at the reservoir entrance to the canal, near the 

River Road bridge crossing and below the Recreation Dam on the south shore. Below the Recreation 

Dam, bedrock cliffs are prominent behind a gently sloping shore zone. 

3.3.1.1.7 Erosion Features 

Near the east side of the River Road crossing, bedrock outcrops are interrupted by areas of erosion of 

weathered bedrock. Soils are exposed along the slope face, tree roots are exposed at the nearly vertical 

upper top-of-bank, and weathered rock fragments lie on the steeply sloping surface below the upper zone. 

This erosion site is downslope of the south end of the east dike structure. This site is monitored daily; the 

dike is unaffected by the erosion and is in excellent condition. 

Active gully-type erosion by intermittent spillway flows and runoff have created deep crevasses in a steep 

channel downstream of the Recreation Dam spillway on the north side of the dam (Figure 3.3.1.1.7-1). 

The erosion is not impacting the spillway. Exelon continuously reviews conditions at this location to 

assess any future need for erosion abatement. On the north shoreline of the finger-shaped cove formed by 

the tributary immediately below (south of) the Recreation Dam, a top-of-bank erosion scarp face (about 2 

feet) in soils developed from the underlying bedrock was observed. A relatively steeply sloping exposure 

of alluvial material lies at the base of the scarp with slump features. 

3.3.1.1.8 Shoreline Erosion Inventory 

Shoreline types are categorized and mapped by the predominance of erosion properties as follows: 

• High Erosion: Severe erosion; may adversely affect a valuable resource (e.g., infrastructure) or create a 

potential safety hazard. 

• Moderate Erosion: Site of top-of-slope erosion of unconsolidated material; may show signs of slumping. 

Resource not adversely affected. 

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• Minimal to None: Unweathered bedrock covered with a veneer of fragmented weathered bedrock, 

colluvium and alluvium. Alluvium predominates where tributaries enter the Reservoir. 

The shoreline erosion inventory of the Muddy Run Reservoir is illustrated in Figure 3.3.1.1.8-1. Erosion 

along the Muddy Run Reservoir can be categorized as minimal to none with the exception of the three 

sites described above. 

3.3.1.2 Environmenutal Effects 

Existing, relevant, and reasonably available information is sufficient to determine the potential effects of 

the Project on geologic resources. Accordingly, FERC’s Study Determination did not require that Exelon 

perform any studies related to geologic impacts. Exelon does not propose any activities that would 

measurably increase shoreline erosion or deposition of sediment in Project reservoirs. The observed 

erosion is localized in nature and is caused by the Power Reservoir fluctuations in combination with 

spillway discharge, surface runoff, mass wasting and wind-generated waves. Overall, the effects of 

erosion at the Muddy Run Project are minimal. 

3.3.1.3 Cumulative Effects 

Council of Environmental Quality (CEQ) regulations define ‘cumulative effects’ as “the impact on the 

environment which results from the incremental impact of the action when added to other past, present, 

and reasonably foreseeable future actions regardless of what agency (Federal or non-Federal) or person 

undertakes such other actions” (40CFR§1508.7). 

For this analysis, the action is the relicensing and continued operation of the Muddy Run Project. The 

cumulatively affected resource is the Lower Susquehanna River Basin and the Chesapeake Bay. The 

geographic scope of this analysis is defined by the scope of EPA’s Bay Total Maximum Daily Load 

(TMDL), which covers a 64,000-square-mile area across seven jurisdictions. The temporal scope of this 

analysis includes a discussion of the past, present, and reasonably foreseeable future actions, and their 

effects on the resource based on a new license term. 

The potential impact of the Project is associated with whether the continued operation of the Muddy Run 

Project affects the sediment budget of the Lower Susquehanna River, which had already been altered by 

Holtwood Dam (built 1910), the Conowingo Project (built 1928) and the Safe Harbor Dam (built 1930- 

1931) when the Project became commercially operational in 1967. 

E-44



The cumulative impact of the Project on the affected resource occurs within the context of watershed 

activities that directly control sediment reaching the Project. Regulations and voluntary incentives 

implemented to date by federal, state and local governments; non-governmental organizations; and 

stakeholders in the agricultural, storm water, and wastewater sectors of the watershed have reduced 

sediment/nutrient loads reaching the Muddy Run watershed, including the Project, but not enough to 

prevent Chesapeake Bay and its tidal tributaries from becoming impaired waterbodies unable to meet 

water quality criteria. 

Operational capacity will not be added and physical modification will not be made under the proposed 

action. The cumulative impacts of the action are evaluated within the context of the EPA Chesapeake 

Bay TMDL process and planned expansion program of the Holtwood Dam Project under possible future 

scenarios. Shoreline erosion due to reservoir level fluctuations occurs, but because the shoreline consists 

largely of weathered and unweathered bedrock the erosion is minimal and protracted. The Project does 

not alter the sediment budget of the Lower Susquehanna River and, therefore, does not impact sediment 

introduction or transport to Chesapeake Bay. The Proposed Actions of the Project, in combination with 

other activities within the watershed, will not alter this condition for the reasonably foreseeable future. 

Thus, the impact of the Project on sediment, when added to other past, present, and reasonably 

foreseeable future actions, is negligible or non-existent. 

3.3.1.4 Proposed Environmental Measures 

As the upper reservoir was created expressly for power generation and shoreline erosion has been deemed 

minimal, no additional shoreline erosion protection measures are currently proposed. If, during the term 

of the new license, Exelon proposes new Project facilities or activities that were not addressed in FERC’s 

NEPA process, prior to construction Exelon would ensure that all proposals, where applicable, are 

consistent with Exelon’s measures in the Shoreline Management Plan for the Muddy Run Project. This 

Plan will address potential erosion impacts from new Project facilities. 

3.3.1.5 Unavoidable Adverse Effects 

Unavoidable adverse impacts of Muddy Run operations include shoreline erosion due to reservoir level 

fluctuations. As the shoreline is largely weathered and unweathered bedrock, shoreline erosion will be 

minimal. 

E-45



TABLE 3.3.1.1.2-1: BEDROCK GEOLOGIC UNITS OF THE PROJECT AREA 

Unit 

Map 

Symbol 

Age Description 

Octoraro Xo Probably lower Albite-chlorite schist with 

Formation 

Paleozoic phyllite, hornblend gneiss, 

and granitized members 

Peters Creek Xpc Probably lower Chlorite-sericite schist with 

Schist 

Paleozoic 

interbedded quartzite 

Ultramafic rocks Xu Probably lower Serpentinite with pyroxenite 

Paleozoic 

and steatite 

(Source: PGS 2001) 

E-46



TABLE 3.3.1.1.3-1: SURFICIAL GEOLOGIC UNITS OF THE PROJECT AREA 

Unit Description 

Rock and alluvium undivided Flat to vertical surfaces of schist bedrock either bare or covered with 

alluvium. Exposed areas in bed of Susquehanna River. 

Schist bedrock and colluvium 

undivided 

Surfaces with low to steep slopes underlain by unweathered or 

weathered schist bedrock and thin (< 6 feet), discontinuous deposits of 

colluvium. 

Rock upland Nearly flat upland surface underlain unusually by weathered schist 

bedrock, sometimes by unweathered schist bedrock. Little to not 

colluvium is present. 

Alluvium Material underlies narrow to broad, flat-surfaced floodplains of 

perennial streams. Comprises stratified sand, silt and clay in upper 

part; same plus gravel in lower part. Generally less than ten feet thick. 

Saprolite Upland surface underlain by isovolumetrically weathered, 

untransported bedrock that retains its original character but has lost up 

to half its original bulk density. 

Alluvium and colluvium undivided Alluvium and colluvium are mapped together where the valley in 

which they occur is too narrow to map the units separately at 1:24,000 

scale. 

Colluvium Colluvium is unsorted and unstratified to crudely stratified debris 

derived from underlying bedrock. Comprised of fragments set in 

finer-grained matrix. Platy fragments in schist bedrock areas. 

Mapped where greater than six feet thick. 

(Source: Sevon 1996) 

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TABLE 3.3.1.1.4-1: SOIL UNITS OF PROJECT AREA IN MUDDY RUN RESERVOIR AREA 

Map Unit Map Symbol Description 

Baile silt loam Ba Baile soils are hydric and make up 85 percent of this map 

unit. Very deep and poorly drained; potentially highly 

erodible; in depressions and on footslopes; forms in local 

alluvium and weathered micaceous schist. Other minor 

Chester silt loam, 0 to 3 percent 

slopes 

Chester silt loam, 3 to 8 percent 

slopes 

Chester silt loam, 8 to 15 

percent slopes 

Glenelg silt loam 3 to 8 percent 

slopes 

Glenelg silt loam 8 to 15 percent 

slopes 

Glenelg silt loam 15 to 25 


Glenville silt loam, 3 to 8 


Manor silt loam, 3 to 8 percent 

slopes 

Manor silt loam, 8 to 15 percent 

slopes 

E-48 

soils make up the remainder of the map unit. 

CbA Chester soils make up 90 percent of this map unit. Very 

deep and well drained; not highly erodible; forms in 

weathered micaceous schist. Hydric Baile soils make up 3 

percent of the map unit. Other minor soils make up the 

remainder of the map unit. 

CbB Chester soils make up 90 percent of this map unit. Very 

deep and well drained; potentially highly erodible; forms in 

weathered micaceous schist. Hydric Baile soils make up 3 



CbC Chester soils make up 90 percent of this map unit. Very 

deep and well drained; highly erodible; forms in weathered 

micaceous schist. Other minor soils make up the remainder 

of the map unit. 

GbB Glenelg soils make up 85 percent of this map unit. Very 

deep and well drained; potentially highly erodible; forms in 

weathered micaceous schist and gneiss. Other minor soils 

make up the remainder of the map unit. 

GbC Glenelg soils make up 85 percent of this map unit. Very 


micaceous schist and gneiss. Other minor soils make up the 


GbD Glenelg soils make up 85 percent of this map unit. Very 


micaceous schist and gneiss. Other minor soils make up the 


GdB Glenville soils make up 85 percent of this map unit. Very 

deep and moderately well to somewhat poorly drained; 

potentially highly erodible. Hydric Baile soils make up 10 



MaB Manor soils make up 90 percent of this map unit. Very 

deep and well drained to somewhat excessively drained; 

potentially highly erodible; forms in weathered micaceous 

schist. Other minor soils make up the remainder of the map 

unit. 

MaC Manor soils make up 90 percent of this map unit. Very 


highly erodible; forms in weathered micaceous schist. Other 

minor soils make up the remainder of the map unit.




Manor silt loam, 15 to 25 


Manor very stony silt loam, 3 to 

8 percent slopes 

Manor very stony silt loam, 8 to 


MaD Manor soils make up 90 percent of this map unit. Very 


highly erodible; forms in weathered micaceous schist. Other 

E-49 

minor soils make up the remainder of the map unit. 

MbB Manor soils make up 90 percent of this map unit. Very 

deep and well drained to somewhat excessively-drained; 

potentially highly erodible; forms in weathered micaceous 

schist. Other minor soils make up the remainder of the map 

unit. 

MbD Manor soils make up 90 percent of this map unit. Very 


highly erodible; forms in weathered micaceous schist. 

Other minor soils make up the remainder of the map unit. 

Manor very stony silt loam, 25 MbF Manor soils make up 90 percent of this map unit. Very 

to 60 percent slopes 


highly erodible; forms in weathered micaceous schist. 


Newark silt loam Nc Newark soils make up 85 percent of this map unit. Deep 

and somewhat poorly drained; not highly erodible; forms on 

floodplains. Hydric Holly soils make up 12 percent of the 

map unit. Other minor soils make up the remainder of the 

map unit. 

Udorthents, loamy Ud Udorthents make up 90 percent of this map unit. Well 

drained; potentially highly erodible; typically high in rock 

fragments. Hydric wet spots develop in 2 percent of the 

map unit. Other minor soils make up the remainder of the 

map unit. 

(Source: SSURGO)



TABLE 3.3.1.1.4-2: SOIL UNITS OF PROJECT AREA IN TRANSMISSION LINE CORRIDOR 


Chester silt loam, 3 CbB Chester soils make up 90 percent of this map unit. Very deep and well 


drained; potentially highly erodible; forms in weathered micaceous schist. 

Hydric Baile soils make up 3 percent of the map unit. Other minor soils 


Comus silt loam Cm Comus soils make up 90 percent of this map unit. Deep and well drained; 

potentially highly erodible; forms in micaceous alluvial material on 

Fluvaquents and 

Udifluvents, loamy 

Glenelg silt loam 3 


Glenelg silt loam 8 


Glenville silt loam, 

3 to 8 percent 

slopes 

Mt. Airy and 

Manor soils, 3 to 8 


Mt. Airy and 

Manor soils, 8 to 15 


Mt. Airy and 

Manor soils, 15 to 


Mt. Airy and 

Manor soils, 25 to 

60 percent slopes, 

extremely stony 

floodplains. Other minor soils make up the remainder of the map unit. 

Ff Fluvaquents make up 60 percent of this map unit and Udufluvents make up 

25 percent. Silty sediment frequently flooded and reworked by rivers. 

Hydric Holly soils make up 15 percent of the map unit. Occur mainly in 

E-50 

areas with low flow velocities. 

GbB Glenelg soils make up 85 percent of this map unit. Very deep and well 

drained; potentially highly erodible; forms in weathered micaceous schist 

and gneiss. Other minor soils make up the remainder of the map unit. 

GbC Glenelg soils make up 85 percent of this map unit. Very deep and well 

drained; highly erodible; forms in weathered micaceous schist and gneiss. 


GdB Glenville soils make up 85 percent of this map unit. Very deep and 

moderately well to somewhat poorly drained; potentially highly erodible. 

Hydric Baile soils make up 10 percent of the map unit. Other minor soils 


MOB Mt. Airy soils make up 56 percent of this map unit and Manor soils make 

up 30 percent. Moderately deep to very deep and well-drained to 

somewhat excessively drained; potentially highly erodible; forms in 

weathered micaceous crystalline rock. Other minor soils make up the 


MOC Mt. Airy soils make up 55 percent of this map unit and Manor soils make 

up 25 percent. Moderately deep to very deep and well drained to 




MOD Mt. Airy soils make up 60 percent of this map unit and Manor soils make 

up 20 percent. Moderately deep to deep and well drained to somewhat 

excessively drained; potentially highly erodible; forms on weathered 

micaceous crystalline rock. Other minor soils make up the remainder of 

the map unit. 

MRF Mt. Airy soils make up 60 percent of this map unit and Manor soils make 

up 20 percent. Moderately deep to very deep and well drained to 




Rock outcrop Rc Bedrock exposures on surface. 

(Source: SSURGO)



FIGURE3.3.1.1.5-1: WEATHERED BEDROCK 

Contact Of Two Different Size Classes Of Fragmented Bedrock Along Muddy Run Reservoir Shore 

Dipping Bedrock Is Almost Hidden As It Protrudes Veneer Of Weathered Bedrock 

E-54



FIGURE 3.3.1.1.5-2: OUTCROPPING BEDROCK 

Dipping Bedrock Protrusion 

Near-Vertical Bedrock Cliff 

E-55



FIGURE 3.3.1.1.5-3: IN SITU TREE STUMPS 

Exposed In Situ Tree Stump 

Tree Stumps Are Randomly Distributed On Sloping Shore 

Slump Feature In Foreground 

E-56



FIGURE 3.3.1.1.5-4: MEANDERING THALWEGS 

Alluvium Of Broad Swale Exposed at Low Water Levels In Muddy Run Reservoir 

Meandering Thalweg Conveys Water to The Reservoir 

Close-Up Illustrating Swale Bank Covered With Tree Stumps 

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FIGURE 3.3.1.1.7-1: EROSION AT RECREATION DAM 

Series of crevasses has developed adjacent to Recreation Dam 

Steep walled crevasse viewed from reservoir side 

Steep walled crevasse viewed from top-of-slope 

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3.3.2. Water Resources 


3.3.2.1.1 Water Quantity 

Lower Susquehanna River Hydrology and Streamflow 

The Susquehanna River has a total drainage area of 27,510 square miles, of which 6,270 square miles are 

in south-central New York, 20,950 square miles are in central Pennsylvania, and 280 square miles are in 

northeastern Maryland. Of this total drainage area, approximately 27,100 square miles are located above 

Conowingo Dam. 

The lower Susquehanna has several hydroelectric projects that collectively influence the river’s flow 

characteristics. In the approximately 45 river miles between the Marietta, PA USGS gage (No. 

01576000) and the mouth of the Susquehanna at Chesapeake Bay, there are three main channel dams and 

one pumped storage facility, all constructed for the purpose of hydroelectric energy generation. In 

addition to the hydroelectric energy generation, there are several other withdrawals for various uses, 

including power generation cooling water as well as drinking water withdrawals. 

The average annual flows between water year (WY 12 ) 1968 and 2009 measured at the Marietta and 

Conowingo USGS gages were 39,686 and 41,026 cfs, respectively. A statistical analysis of lower 

Susquehanna River flows is described by Gomez and Sullivan (2012). Annual and monthly sub-daily 

flow exceedance percentiles at the Conowingo and Marietta USGS gages show that the Susquehanna 

experiences a wide range of flows that vary by season (Table 3.3.2.1.1-1 and Table 3.3.2.1.1-2). 

The Project Power Reservoir is located on Muddy Run, a small tributary to the Susquehanna. The 

average annual flow from Muddy Run to the Muddy Run Reservoir is approximately 7 cfs. There are no 

USGS gaging stations on Muddy Run. 

Major Water Users 

There are eight main water users along the lower Susquehanna downstream of the Marietta, PA USGS 

gage, which is at RM 45 (Figure 3.3.2.1.1-1). The eight water users, in upstream to downstream order, 

are: 

12 Water year refers to a year that begins on October 1 and ends September 30. For example, WY 1968 begins 

October 1, 1967 and ends September 30, 1968. 

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� Safe Harbor Hydroelectric Project - The farthest upstream water user, located at RM 31. Safe Harbor 

is a peaking Project, with an installed capacity of 417.5 MW and an estimated hydraulic capacity of 

110,000 cfs. 

� Holtwood Hydroelectric Project - Located at RM 24, Holtwood Dam has a powerhouse with a total 

hydraulic capacity of approximately 31,500 cfs and an installed generation capacity of 107 MW. 

FERC recently issued PPL a License Amendment to expand the capacity at the Holtwood Project. 

Construction began in 2010, and when completed will result in a total generation capacity of 196 MW 

and total hydraulic capacity of 61,460 cfs. 

� Muddy Run Pumped Storage Project - Located at RM 22, Muddy Run uses Conowingo Pond as a 

lower storage reservoir. The powerhouse turbines have a total discharge capacity from the 

powerhouse of 32,000 cfs. The total powerhouse pumping capability is 28,000 cfs. 

� Peach Bottom Atomic Power Station - PBAPS withdraws cooling water from Conowingo Pond, and 

is located at approximately RM 17. PBAPS has two units, with a total generating capacity of 2,186 

MW. A total of approximately 2,230 MGD (3,450 cfs) is required at full power operation. 

� The York Energy Center - This facility has a 1,100 MW electric generation facility that withdraws 

cooling water approximately 8 miles upstream of Conowingo Dam, at RM 18. The facility has a 

permitted is allowance of 12.62 MGD(19.5 cfs)from Conowingo Pond 

� The City of Baltimore - Currently, the City of Baltimore is approved by the SRBC to withdraw a 

maximum of 250 MGD (387 cfs) from the Conowingo Pond, but is currently limited by its pumping 

capacity to a withdrawal of approximately 137 MGD (212 cfs). During low flow periods 13 on the 

Susquehanna River, the maximum 30-day average withdrawal is reduced to 64 MGD (99 cfs). The 

Conowingo Pond withdrawal is principally used during major drought periods or under emergency 

operating conditions. 

� Chester Water Authority - The SRBC has permitted Chester Water Authority to withdraw up to 30 

Millions Gallons per Day (MGD) (46 cfs) of water from Conowingo Pond. 

13 Baltimore’s low flow withdrawal restriction refers to when Marietta flow is below Conowingo’s 

seasonal minimum flow. 

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� Conowingo Hydroelectric Project - The Conowingo Project has an installed generation capacity of 

573 MW and a hydraulic capacity of 86,000 cfs. 

Water Withdrawal and Return Characteristics 

The Project operates by pumping water from the lower reservoir (Conowingo Pond) to the upper Power 

Reservoir using pump/turbines in pumping mode and then passing the water from the upper Power 

Reservoir back through the pump/turbines in generation mode. Typically, pumping occurs during low- 

load periods when energy costs are low, while generation occurs during high-load periods. 

Muddy Run’s Power Reservoir has an effective storage of approximately 33,894 acre-ft at elevation 520 

ft 14 . Conowingo Pond has an effective storage of approximately 34,050 acre-ft between Pond elevation 

105.2 ft and 109.2 ft, which is the typical fluctuation range even though the Conowingo FERC license 

conditions allow fluctuations between 101.2 ft and 110.2 ft. The Muddy Run powerhouse turbines have a 

maximum discharge capacity from the powerhouse of 32,000 cfs. The maximum total powerhouse 

pumping capability is 28,000 cfs. Both of these values are a function of the operating head at the Project, 

and, therefore, vary with Conowingo Pond and Muddy Run Power Reservoir elevations. 

Using hourly Project operations data from 2008 thru 2010, flow statistics were calculated to illustrate the 

water withdrawal and return characteristics of the Muddy Run Project. For each year, a 30-day low flow 

period (between August and September) and a 30-day high flow period (between March and April) was 

analyzed (GSE and Normandeau Associates 2012a). 

Table 3.3.2.1.1-3 and Table 3.3.2.1.1-4 illustrate, for each 30-day high flow period (between March and 

April) and 30-day low flow period (between August and September), the 1) average daily withdrawal 

from Conowingo Pond; 2) average daily discharge to Conowingo Pond; 3) maximum daily withdrawal 

from Conowingo Pond; 4) the maximum daily discharge to Conowingo Pond; 5) the maximum hourly 

withdrawal from Conowingo Pond; and 6) the maximum hourly discharge to Conowingo Pond. The 

corresponding 30-day average flows from the Marietta USGS gage are also shown. 

14 All elevations in this document refer to the National Geodetic Vertical Datum of 1929 (NGVD 

1929), unless otherwise noted. This is in contrast to the traditionally used datum at the Conowingo 

Project, Conowingo Datum, which is 0.7 ft lower than NGVD 1929, such that elevation 520 ft 

NGVD1929 is equal to elevation 519.3 ft Conowingo Datum. 

E-62



3.3.2.1.2 Water Quality 

Water Quality Standards and Classifications 

The Pennsylvania Code (Title 25, Chapter 93) establishes narrative and numeric water quality criteria 

needed to support a variety of protected water uses (Table 3.3.2.1.2-1). All surface waters in 

Pennsylvania are protected for aquatic life (warm water fishes), water supply (potable, industrial, 

livestock, wildlife and irrigation) and recreation (boating, fishing, water contact sports and aesthetics). 

The segment of the Susquehanna River between the confluence with the Juniata River and the 

Pennsylvania-Maryland border where the Project is located has a warm water fishes (WWF) designated 

water use. In addition to general/narrative standards that are applicable to all surface waters, specific 

water quality criteria for parameters such as pH, alkalinity, bacteria, color, dissolved oxygen (DO), 

temperature and certain ions, metals and nutrients are established for critical use (i.e., the most sensitive 

designated or existing use designated for protection). 

Water quality parameters that have been most closely monitored with regard to the operation of the 

Muddy Run Project include DO and temperature. For WWF waters, the Pennsylvania DO standard is a 

minimum daily average of 5.0 milligrams per liter (mg/L) with an instantaneous minimum of 4.0 mg/L. 

The standard recognizes the natural process of stratification in lakes, ponds and impoundments and 

applies to flowing water and the epilimnion of a naturally stratified lake, pond or impoundment and 

throughout the water column for non-stratified bodies of water. 

Maximum temperature limits vary with the time of year. The maximum temperature criteria for WWF 

are summarized in Table 3.3.2.1.2-2. These temperature standards apply only to water affected by heated 

discharges; no heated discharge emanates from the Muddy Run Project. In addition to these temperature 

criteria, heated waste sources may not result in a change of temperature in receiving water of more than 

2°F during a one-hour period. 

Historical Water Chemistry 

Muddy Run Project Discharge 

Continuous monitoring of water temperature, DO and pH was conducted in the Project discharge area in 

the summer (August 8 – September 3) of 2006 (Exelon 2009). Only one month was monitored due to 

unusually high river inflows in the latter half of July and early September. 

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Table 3.3.2.1.2-3 summarizes the data collected during monitoring in summer 2006. The water quality 

data were in compliance with the Pennsylvania Water Quality Standards for water temperature, DO and 

pH at all times. The minimum instantaneous DO value measured was 5.2 Milligrams Per Liter (mg/L), 

which is above the daily average standard of 5.0 mg/L and instantaneous value of 4.0 mg/L. Likewise, 

pH measurements remained well within the standard range of 6.0 to 9.0 su. The maximum water 

temperature recorded in the tailrace was 86.7 degrees Fahrenheit (°F). Project discharge temperatures 

reflected those in the inflow to Conowingo Pond (Holtwood Dam). River inflow was 7,200 to 76,200 cfs 

during the study with the lowest values (20,000 cfs) occurring August 20-September 3. Historically, average daily August river flows are less 

than 10,000 cfs about 50% of the time and greater than 20,000 cfs about 10% of the time (Normandeau 

Associates 2000). 

Daily fluctuations in temperature of 1.0°F were typical with variations in pH usually



Existing Water Chemistry 

Exelon conducted water quality monitoring within the Muddy Run Power Reservoir and tailrace in 2010 

(Normandeau Associates and GSE 2012a) and 2011 (Normandeau Associates and GSE 2012b). The 

2010 objectives were to characterize the water quality conditions associated with the Muddy Run Project 

and analyze the Project’s operation-related (pumping, generating, or idle) effects on water temperature, 

dissolved oxygen (DO), pH, specific conductivity, turbidity, and chlorophyll a. The 2010 objectives were 

met by implementing two sampling schemes, one each for the Power Reservoir and tailrace: (1) bi- 

weekly sampling from April through October 2010 to collect water quality depth profile data along a 

single transect (Stations 001, 002, and 003) in the Power Reservoir, and (2) continuous monitoring of 

water temperature, DO, pH, and specific conductivity at the Units 1-2 cylinder gate (Station 004, Power 

Reservoir) and the other in the tailrace (Station 005) in the discharge from Units 3 and 4. 

The 2011 study objectives were to characterize the current water quality conditions associated with the 

Muddy Run Project and analyze the effects of Project operations (pumping, generating, or idle) on water 

temperature, DO, pH, specific conductivity, and turbidity. The 2011 objectives were met by 

implementing two sampling schemes, one each for the Power Reservoir and tailrace: (1) weekly sampling 

to collect water quality depth profile data at two locations (Stations MR 1103 and 003) in the Power 

Reservoir, and three locations (Stations MR 1106, MR 1107, and MR 1109) near the tailrace both upriver 

and downriver of the Project, and (2) continuous monitoring of water quality parameters (water 

temperature, DO, pH, and specific conductivity) at the Units 1-2 cylinder gate (MR 1104), from the 

tailrace at Units 1 and 2 (MR 1105) and 0.25 mi upriver of the Project (MR 1107) 

Power Reservoir Sampling 

2010 Sampling 

A classic thermal stratification (decrease of 1°C per 1 m increase in depth) was absent in Muddy Run 

Power Reservoir during the 2010 sampling program. The minimum and maximum surface water 

temperature values recorded along the sampled transect in the Power Reservoir were 52.2 °F (11.2 °C) on 

April 5 and 84.6 °F (29.2 degrees Centigrade)(°C) on July 26. The minimum and maximum 30 meter 

(98.4 feet)(ft) depth water temperature values were 48.2°F (9.0°C) on April 5 and 84.2°F (29.0 °C) on 

July 26. 

The seasonal DO pattern followed an opposite pattern to that of water temperature and paralleled that of 

river flows. As the season progressed, surface DO decreased, as did river flows, with a distinct strong 

E-65



vertical stratification (a difference in DO of greater than 5.0 mg/L between surface and at depths deeper 

than 20 ft) occurring at Stations 001 (1.7 miles from the intake towers) and 002 (1.3 miles from the intake 

towers) in August. Although a DO stratification of this magnitude and strength was not observed at 

Station 003 (located 0.5 miles from the intake towers), DO was less than 5.0 mg/L at depths deeper than 

25 ft in July and throughout the water column in August. DO values, though generally homogeneous 

throughout the water column at other locations profiled, were less than 5.0 mg/L in late June through 

early September. Because Station 003 is located near the head of the intake canal and is subject to 

frequent exchange of water transfer it did not exhibit a strong stratification and appeared well mixed at 

most times. 

The minimum and maximum surface pH values recorded along the single transect in Muddy Run 

Reservoir were 7.0 and 8.6 su, respectively. Although variations between dates were evident, little 

difference occurred between locations on a given sampling date. These values are within the range 

observed in the past and were within the PADEP standards. 

Chlorophyll a values ranged from 0.401 to 20.9 mg/m 3 during the 15 bi-weekly sampling events, April 

through October 2010. The minimum value (0.401 mg/m3) was recorded on June 28 and August 23, and 

the maximum value (20.9 mg/m3) on May 3 and May 17. 

Continuous water quality data collected at the Muddy Run Project in 2010 indicated that pH values were 

mostly within the Pennsylvania Water Quality Standards (6.0-9.0 inclusive). 

The 2010 continuous monitor data indicated that all instantaneous hourly DO values were greater than 4.0 

mg/L in April through June, and in October. However, some DO values did not conform to the 

Pennsylvania water quality standards (no instantaneous values less than 4.0 mg/L and average daily 

values to be equal to or greater than 5.0 mg/L) during the summer. A total of 70 instantaneous hourly DO 

values were less than 4.0 mg/L with most (42 or 60%) recorded at the cylinder gate monitor in August 

when the Project was in an idle mode. The average daily DO value was less than the Pennsylvania State 

standard of 5.0 mg/L on seven days in August and one day in September at the cylinder gate (Station 004) 

monitor. 

E-66

2011 Sampling 



Vertical water temperature profiles at two locations (Stations MR 1103 and MR 003) in the Power 

Reservoir were sampled on nine dates in July and August 2011. None of the collected profiles indicated a 

classic thermal stratification (decrease of 1°C per 1 m increase in depth or 0.55°F decrease in temperature 

per 1 ft increase in depth). The minimum and maximum surface water temperature values recorded at the 

two stations sampled in the Power Reservoir were 75.2°F (24.0°C) and 85.5°F (29.7°C), with highest 

values in July and lower values in August. The two stations’ minimum and maximum 65.6-98.4 ft (20-30 

meter) depth water temperatures were 75.2°F (24.0°C) and 85.3°F (29.6°C), with highest values in July 

and lower values in August. 

DO stratification in the Power Reservoir occurred mostly in mid July through early August, but varied by 

depth and location. Some DO profiles at Stations 003 and MR 1103 showed substandard values at various 

depths in late July and early August. Stratification was observed at Station 003 between July 18 (surface 

DO 7.2 mg/L and 98.4 ft DO 3.6 mg/L) and August 1 (surface DO 6.1 mg/L and 98.4 ft DO 2.9 mg/L). A 

weaker DO stratification (surface DO was 6.3 mg/L and DO at the average bottom depth of 65 ft was 2.4 

mg/L) was observed on August 1 at Station MR 1103. Around the same time period, Stations 003 and 

MR 1103 experienced a weak inverse DO stratification (higher DO in deeper water and lower DO in 

surface water), which was likely due to more oxygenated Conowingo Pond water being pumped into the 

Power Reservoir. 

Overall, at Station MR 1104, hourly DO measurements of less than 4.0 mg/L were measured 15% of the 

time between July 16 and August 7. At MR 1104, hourly DO values less than 4.0 mg/L occurred during 

all three operational scenarios. Out of a total of 1,454 hourly DO observations, 48 (3.0%) hourly values 

less than 4.0 mg/L occurred during the idle mode, 27 (1.9%) during generation, and 8 (0.6%) during the 

pumping mode. MR 1104 continuous monitor DO measurements were variable, mainly due to 

stratification within the Muddy Run reservoir. A notable effect of Project operation on DO at MR 1104 

was the consistent increase in DO during the pumping mode as a result of the more highly oxygenated 

river water. 

The minimum and maximum surface pH values recorded at the two stations in Muddy Run Reservoir 

were 7.2 and 8.4, respectively. These values comply with the PADEP standards. The minimum and 

maximum surface turbidity values recorded at the two stations in Muddy Run Reservoir were 3.1 and 

26.0 Nephelometric Turbidity Unit (NTU), respectively. These values comply with PADEP turbidity 

standards (≤ 40 NTU) between May 15 and September 15). 

E-67

Muddy Run Tailrace Area 

2010 Sampling 



Water quality was sampled at one location in 2010 (Station 005), a continuous monitoring location. The 

water quality parameters collected included water temperature, DO, pH and specific conductivity. 

The maximum and minimum temperatures recorded at the tailrace monitor were 30.0°C (86.0°F) and 

14.2°C (57.6°F), respectively. 

Relative to the historical period (1956-2009), water temperatures in the 2010 study period were higher (up 

to 10°F or 5.6°C in some months) in April through September and lower in October. There were more 

frequent occurrences of average daily water temperatures greater than 80°F (26.7°C) in 2010 summer 

than in the historical period. 

DO decreased from April highs (≥ 9.0 mg/L) to mid-August lows (mostly between 4.0 to 6.0 mg/L); 

fluctuated thereafter and generally increased in September through October. This pattern of DO variation 

coincided with increasing water temperature from April through August (generally > 27.0 °C or > 80.0 °F 

in July-August) and decreasing river flows (less than 8,000 cfs in August). 

At the tailrace deck (Station 005) monitor, the average daily DO value was less than 5.0 mg/L on three 

days in July and one day in August. Instantaneous DO values were less than 4.0 mg/L on 14 occasions 

(12 times in July and 2 times in August). Changes to Conowingo Pond water quality, as indexed by 

temperature and DO profiles taken at a transect approximately 3 mi downstream of Muddy Run, were not 

detectable on sampled dates. Little variation in temperature or DO across the sampled transect locations 

was noted. This suggests the influence of substandard DO discharge from Muddy Run may be localized 

to near field areas. 

Values of pH generally fluctuated between 7.0 and 8.0, with the lowest pH of 6.7 and highest of 9.1 su 

units. 

2011 Sampling 

The tailrace sampling included three water quality profile locations (MR 1106, MR 1107 and MR 1109) 

near the immediate tailrace both upriver and downriver of the Project, and two continuous water quality 

stations (MR 1105 and MR 1107) (Figure 3.3.2.1.2-1). The two tailrace continuous water quality stations 

were located inside the plant at a header pipe that draws water from the tailrace at Units 1 and 2 (MR 

1105), as well as a station 0.25 mi upriver of the Project (MR 1107). 

E-68



Tailrace water temperatures were observed through vertical profiles (MR 1106, MR 1107, and MR 1109) 

and continuous monitoring stations (MR 1105, MR 1107). The minimum and maximum surface water 

temperature values recorded at the three vertical profile stations were 75.0°F (23.9°C) and 87.1°F 

(30.6°C), respectively, with the highest values in July and lower values in August. The minimum and 

maximum bottom depth water temperature values recorded were 75.0°F (23.9°C) and 86.7°F (30.4°C), 

respectively. No temperature stratification was observed at any of the tailrace monitoring locations. The 

maximum and minimum temperatures at MR 1107 were 30.7°C (87.3°F) and 22.3°C (72.1°F), 

respectively. Diurnal temperature cycles were observed at both continuous monitoring stations. The 

diurnal difference in water temperature was more pronounced at the Muddy Run discharge station (MR 

1105), particularly in August, suggesting that the ambient temperature of Muddy Run Reservoir water is 

more diurnally influenced than Conowingo Pond inflows. 

Tailrace DO levels were observed through vertical profiles (MR 1106, MR 1107, MR 1109) and 

continuous monitoring stations (MR 1105, MR 1107). No DO stratification was observed at any station, 

except for some small differences (1.3 mg/L) in DO at Station 1106 (upriver of Muddy Run Project) on 

August 1. All average daily DO values were above 5.0 mg/L at all stations and dates. Continuous DO 

readings decreased from early July highs of 8.2 mg/L and above to early August lows of 3.5 mg/L, and 

then increased in mid and late August. Low instantaneous DO values coincided with increasing water 

temperature (generally >27.0°C or >80.0°F) and decreasing river flows (



between locations on a given sampling date. All values were within the PADEP pH criteria of 6.0-9.0 

(inclusive) for the duration of the sampling period. 

The minimum and maximum surface turbidity values recorded at the three stations near the immediate 

tailrace were 3.3 and 26.1 NTU, respectively. These data met the PADEP standards for turbidity in a 

warm water fishery (≤40 NTU between May 15 and September 15). 

3.3.2.2 Environmental Effects 

Hydrology and Streamflow 

3.3.2.2.1 Water Quantity 

Under Exelon’s proposed action, the Muddy Run Project would continue to withdraw and discharge water 

from/to Conowingo Pond. During high flow periods, Exelon analysis indicates that average daily 

withdrawals would range from approximately 3,100 to 5,000 MG, and average daily discharges would 

range from approximately 3,200 to 5,100 MG. During low flow periods, Exelon average daily 

withdrawals would range from approximately 4,500 to 5,000 MG, and average daily discharges would 

range from approximately 4,600 to 4,900 MG. These operations would continue to alter Conowingo 

Pond water levels, on an intra-daily timeframe. 

Other than the evaporative losses due to the upper reservoir, which are small compared to other 

consumptive uses on the Pond (drinking water, industrial cooling water, etc.), the Muddy Run Project 

does not result in any net water loss to the Susquehanna River Basin. While operations change the water 

levels in Conowingo Pond, water does not leave or bypass any portion of the Susquehanna River due to 

Project operations. The impacts to water quantity associated with the continued operation of the Muddy 

Run Project would be minor. 

Of all the Conowingo Pond water users, Muddy Run requires the highest water levels (105.2 ft) to 

withdraw water, followed by PBAPS (104.2 ft). While Conowingo’s license permits water levels to 

range between 101.2 ft and 110.2 ft, in practice Exelon maintains water levels high enough to 

accommodate Muddy Run and PBAPS withdrawals. Thus, since the Project does not draw water levels 

below 105.2 ft, it does not have any adverse effects on other Conowingo Pond water users, including the 

Conowingo Hydroelectric Project. 

E-70



3.3.2.2.2 Water Quality 

Power Reservoir DO and Thermal Stratification 

Under Exelon’s proposed action, Muddy Run’s Power Reservoir will continue to experience DO 

stratification under certain summer conditions (low flows, high water temperatures), which can result in 

isolated Project discharges into Conowingo Pond which do not meet the current DO standard. 

Monitoring downstream of Muddy Run indicates that the low DO water discharged from the Project 

dissipates quickly, and does not impact overall Conowingo Pond DO levels. The impacts will be short- 

term and minor, occurring during portions of the summer when flows are low and water temperatures are 

high. Exelon’s analysis indicates that thermal stratification of the Muddy Run Power Reservoir does not 

occur. 

Effect on Nutrient Cycling in Muddy Run Reservoir 

Under Exelon’s proposed action, the continued operation of the Muddy Run Project would have a minor 

impact on the sediment and nutrient budget of the Lower Susquehanna River. Watershed efforts by 

various groups have reduced sediment/nutrient loads reaching the Muddy Run watershed, including the 

Power Reservoir. As water withdrawals and discharges are very frequent, and the average residence time 

of water within the Power Reservoir is short, Project operations have little net impact on dissolved and 

particulate nutrient loads received from upstream. As such, there is little impact on the net movement of 

nutrients between the Power Reservoir and Conowingo Pond. 

Effect of Mobilization of Sediment from Pumping 

Exelon’s analysis indicates that mobilization of sediment in the Muddy Run Power Reservoir during 

pumping operations is a relatively minor impact. Turbidity data collected in 2010 and 2011 within the 

Power Reservoir were within Pennsylvania Water Quality Standards (≤ 40 NTU) on all sampling 

occasions, with the exception of one sampling event in June 2010. Mobilization of sediment in 

Conowingo Pond during pumping operations under Exelon’s proposed action is not expected to change 

from existing conditions. 

Effects on Water Quality and State Water Quality Standards 

Under Exelon’s proposed action, Exelon anticipates that the Project will normally meet current 

Pennsylvania water quality standards; however, during isolated summertime periods Project discharges 

E-71



may infrequently not meet DO standards. The 2010 and 2011 water quality studies (Normandeau 

Associates and GSE 2012a and 2012b) showed that: 

� The Project’s Power Reservoir does experience DO (but not temperature) stratification during 

summertime conditions (low flow, high water temperatures); 

� The stratified DO can infrequently result in Project discharges not meeting Pennsylvania DO 

standards; 

� Discharges containing DO that does not meet current standards do not appear to be noticeable in 

Conowingo Pond downstream of the Muddy Run Project, suggesting that the low-DO water 

dissipates quickly. 

� Water quality in terms of temperature, pH, and turbidity, do and will continue to meet 

Pennsylvania Water Quality Standards. 


CEQ regulations define ‘cumulative effects’ as “the impact on the environment which results from the 

incremental impact of the action when added to other past, present, and reasonably foreseeable future 

actions regardless of what agency (Federal or non-Federal) or person undertakes such other actions” 

(40CFR§1508.7). 

For this analysis, the action is the relicensing and continued operation of the Muddy Run Project. The 

geographic scope of this cumulatively affected resource is the Lower Susquehanna River Basin and the 

Chesapeake Bay. The temporal scope of this analysis includes a discussion of the past, present, and 

reasonably foreseeable future actions, and their effects on the resource based on a new license term. 

The potential impact of the Project is associated with whether the continued operation of the Muddy Run 

Project affects water quantity and quality of the Lower Susquehanna River. 

Conowingo Pond Water Withdrawals 

The cumulative impact of the Project on water withdrawals occurs within the context of the presence of a 

series of hydroelectric facilities that directly control the hydrologic regime of the Susquehanna River. 

Operational capacity will not be added and physical modification will not be made under the proposed 

action. The Project contributes to the alteration of the lower Susquehanna River’s hydrology, particularly 

E-72



in terms of water levels and flow regime. The Project directly influences Conowingo Pond water levels, 

and indirectly influences Conowingo Dam outflows. It is difficult to quantify specific Project impacts, as 

Conowingo Pond’s inflows are highly regulated by the upstream lower Susquehanna River hydroelectric 

projects (Safe Harbor and Holtwood). The Project does not directly alter the water quantity of the Lower 

Susquehanna River on a daily basis and, therefore, does not impact water quantities within the 

Chesapeake Bay. The Proposed Actions of the Project, in combination with other activities within the 

watershed, will not alter this condition for the reasonably foreseeable future. 

Water Quality 

The cumulative impact of the Project on water quality occurs within the context of the presence of a series 

of hydroelectric facilities that have the potential to collectively effect the water quality of the 

Susquehanna River. Operational capacity will not be added and physical modification will not be made 

under the proposed action. The Project does not appear to have appreciable impacts on several water 

quality parameters, such as water temperature, pH and specific conductivity, as levels in the Power 

Reservoir matched ambient and upstream conditions well. However, Power Reservoir DO stratification 

does appear to play a role in infrequent (0.1% in 2011) localized discharges containing DO levels that do 

not meet the current instantaneous standard in the Muddy Run tailrace. Upstream and downstream 

monitoring indicated that the DO levels that do not meet the current instantaneous standard was isolated 

to the immediate vicinity of the Muddy Run Project’s discharge into Conowingo Pond, and that other 

projects did not appear to influence DO levels measured in the Project’s Power Reservoir. The Project 

results in a minor, local impact to the water quality of the Lower Susquehanna River and, therefore, does 

not impact the Susquehanna River Basin downstream of the Project or the Chesapeake Bay. The 

proposed actions of the Project, in combination with other activities within the watershed, will not alter 

this condition for the reasonably foreseeable future. 


3.3.2.4.1 Hydrology and Streamflow 

Exelon’s environmental analysis indicates that Project operations alter Conowingo Pond levels, which 

may influence streamflow below Conowingo Dam on an intra-daily basis. However, other than the 

evaporative losses due to the upper reservoir, the Muddy Run Project does not result in any net water loss 

to the Susquehanna River Basin. Consequently, Exelon is not proposing any flow-related measures. 

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3.3.2.4.2 Power Reservoir DO and Thermal Stratification 

Exelon’s environmental analysis indicated that Project impacts resulted in DO stratification in the Muddy 

Run Power Reservoir, but no thermal stratification was observed in the Power Reservoir. The stratified 

Power Reservoir results in releases containing DO levels that do not meet the current instantaneous 

standard during extreme low flow periods. Given the infrequency of these releases, Exelon is not 

proposing any DO-related environmental measures. 

3.3.2.4.3 Effect on Nutrient Cycling in Muddy Run Reservoir 

Exelon’s environmental analysis indicates that Project impacts on nutrient cycling in Muddy Run Power 

Reservoir are minor. Exelon, therefore, is not proposing any measures to address nutrient cycling. 

3.3.2.4.4 Effect of Mobilization of Sediment from Pumping 

Exelon’s environmental analysis indicates that Project impacts on sediment mobilization during pumping 

operation at the Project are minor. Exelon, therefore, is not proposing any environmental measures to 

address sediment mobilization. 

3.3.2.4.5 State Water Quality Standards 

Exelon’s environmental analysis indicates that discharges containing DO levels that do not meet the 

current instantaneous standard are released infrequently (



TABLE 3.3.2.1.1-1: CONOWINGO ANNUAL AND MONTHLY SUB-DAILY (30-MINUTE) FLOW EXCEEDANCE PERCENTILES, IN CFS (WY 

1989-1990, 1992-1993, 1995-2009) 

Exceedance 

Percentile 

Annual January February March April May June July August September October November December 

0 909,000 909,000 264,000 416,000 500,000 278,000 459,000 235,000 179,000 446,000 233,000 302,000 295,000 

5 122,000 176,000 126,000 173,000 189,000 123,000 86,400 70,230 59,100 74,500 81,100 95,900 138,000 

10 85,600 133,000 89,200 132,000 128,000 87,200 72,500 57,800 45,100 58,100 68,100 80,700 97,800 

15 79,000 99,000 81,600 106,000 104,000 81,700 65,000 47,745 32,400 45,900 52,000 74,900 82,700 

20 73,000 84,000 78,100 87,500 88,200 76,200 58,000 38,200 22,800 32,900 41,100 67,200 79,800 

25 67,000 80,200 74,900 82,900 83,800 69,100 50,600 30,400 11,600 23,600 32,800 60,500 75,500 

30 60,800 77,700 71,600 79,320 80,700 65,500 42,700 22,200 6,820 10,500 25,900 53,000 70,400 

35 51,200 73,000 68,300 76,300 77,700 60,500 36,600 10,800 6,550 6,450 21,900 44,700 66,300 

40 41,400 68,300 64,300 73,500 74,400 54,400 29,900 7,460 6,400 6,070 11,600 36,500 61,200 

45 33,000 62,500 59,500 71,100 71,800 46,500 23,900 6,800 6,250 5,790 5,930 30,700 52,800 

50 25,200 56,300 48,300 68,600 69,400 39,400 17,600 6,550 6,070 5,340 4,910 24,100 43,900 

55 17,100 45,900 38,600 64,700 65,900 34,200 8,850 6,350 5,930 4,950 4,680 13,600 34,400 

60 9,650 34,800 30,200 59,100 62,500 27,100 7,280 6,220 5,790 4,630 4,590 6,250 26,600 

65 6,800 26,400 23,300 48,000 55,000 23,200 6,650 6,060 5,690 4,410 4,510 5,010 19,500 

70 6,150 17,600 13,200 38,400 44,680 12,800 6,300 5,880 5,500 4,280 4,420 4,680 7,780 

75 5,690 6,750 6,550 29,800 33,700 10,400 6,070 5,790 5,390 4,040 4,320 4,540 4,500 

80 5,100 4,410 4,410 23,000 24,900 9,640 5,920 5,650 5,190 3,800 4,210 4,450 3,510 

85 4,550 1,870 1,710 7,250 13,700 9,320 5,830 5,550 4,950 3,650 3,840 4,280 1,450 

90 4,120 1,160 1,140 5,100 12,500 9,110 5,650 5,290 4,680 3,470 3,730 3,960 1,020 

95 3,280 959 950 4,460 11,900 8,800 5,390 4,950 3,760 3,050 3,620 3,620 879 

100 257 297 261 1,380 10,000 6,200 4,410 3,070 2,200 1,700 959 756 257 

E-75



TABLE 3.3.2.1.1-2: MARIETTA ANNUAL AND MONTHLY SUB-DAILY (30-MINUTE) FLOW EXCEEDANCE PERCENTILES, IN CFS (WY 1989- 

1990, 1992-1993, 1995-2009) 

Exceedance 

Percentile 

Annual January February March April May June July August September October November December 

0 588,000 588,000 244,000 352,000 448,000 230,000 421,000 249,000 126,000 390,000 198,000 277,000 272,000 

5 119,000 176,000 121,000 172,000 179,000 129,000 84,500 48,000 44,900 73,600 65,800 89,600 127,000 

10 85,800 122,800 98,100 134,000 131,000 82,500 55,100 37,200 26,400 41,900 42,900 68,300 90,800 

15 69,000 98,900 77,200 110,000 107,000 68,700 46,408 31,300 21,700 28,700 33,800 56,600 76,700 

20 58,800 85,200 65,500 94,300 95,200 63,100 39,700 28,400 18,939 22,500 28,600 50,300 67,000 

25 51,000 72,300 58,800 83,000 85,800 56,900 36,300 25,000 16,700 18,300 25,200 42,400 57,826 

30 44,300 63,100 53,500 74,600 77,200 52,900 32,800 21,800 14,400 15,700 22,400 38,200 52,500 

35 38,800 57,000 49,200 68,900 71,600 48,100 30,100 19,200 12,300 13,400 20,100 35,400 47,300 

40 34,200 50,500 45,000 63,900 67,100 43,600 28,300 17,200 11,100 11,600 17,900 32,500 42,100 

45 30,200 44,700 41,200 58,700 62,800 40,100 25,000 14,900 9,630 9,895 15,256 29,000 37,800 

50 27,000 40,600 37,700 52,300 58,500 35,801 22,400 13,400 8,680 8,380 12,800 26,300 34,500 

55 24,000 36,600 32,900 47,400 54,700 33,400 20,000 12,000 7,960 7,320 10,649 24,360 30,700 

60 21,100 31,500 29,900 44,700 50,500 30,800 18,300 11,100 7,340 6,620 9,290 21,500 28,200 

65 18,200 27,500 27,600 41,081 46,800 27,900 16,600 10,300 6,560 6,040 8,243 17,700 25,700 

70 15,600 23,600 25,900 37,800 43,600 25,690 14,900 9,440 6,040 5,590 7,370 14,100 23,600 

75 12,900 21,300 24,100 34,900 39,500 23,700 13,600 8,750 5,630 5,190 6,823 11,000 21,300 

80 10,500 19,600 21,200 31,700 35,700 21,800 12,700 7,740 5,350 4,820 6,307 9,330 19,000 

85 8,130 17,633 18,400 28,800 32,448 19,300 11,900 7,010 5,000 4,400 5,960 7,810 16,800 

90 6,270 15,900 16,691 25,400 27,900 16,700 10,900 6,130 4,400 3,890 5,330 5,920 14,200 

95 5,180 13,900 14,700 23,200 23,400 14,600 8,150 5,270 3,530 3,010 4,500 5,350 8,130 

100 2,130 7,920 8,930 15,100 17,900 10,900 4,580 3,470 2,600 2,130 3,070 4,220 4,700 

E-76

Flow Period 



TABLE 3.3.2.1.1-3: WATER WITHDRAWAL AND RETURN STATISTICS FOR 30-DAY HIGH-FLOW PERIODS 

Average 

Flow at 

Marietta 

USGS gage 

(cfs) 

Average Daily 

Withdrawal 

from 

Conowingo 

Pond (MG) 

Average Daily 

Discharge to 


Pond (MG) 

Maximum Daily 

Withdrawal 

from 


Pond (MG) 

E-77 

Maximum Daily 

Discharge to 


(MG) 

Maximum Hourly 

Withdrawal from 


(MG) 

Maximum 

Hourly 

Discharge to 


Pond (MG) 

Mar 5 -Apr 3, 2008 132,645 5,003 5,089 7,599 8,093 923 984 

Mar 11-Apr 9, 2009 54,194 3,085 3,222 6,275 6,909 792 865 

Mar 13-Apr 11, 2010 96,459 3,344 3,296 6,124 6,405 794 866 

Flow Period 

TABLE 3.3.2.1.1-4: WATER WITHDRAWAL AND RETURN STATISTICS FOR 30-DAY LOW-FLOW PERIODS 

Average 

Flow at 

Marietta 

USGS gage 

(cfs) 

Average Daily 

Withdrawal 

from 


Pond (MG) 

Average Daily 

Discharge to 


Pond (MG) 

Maximum Daily 

Withdrawal 

from 


Pond (MG) 

Maximum 

Daily 

Discharge to 


Pond (MG) 

Maximum 

Hourly 

Withdrawal from 


(MG) 

Maximum 

Hourly Discharge 

to Conowingo 

Pond (MG) 

Aug 28-Sep 26, 2008 6,523 5,053 4,924 7,065 7,344 786 1,013 

Sep 1-Sep 30, 2009 13,722 4,505 4,625 5,818 8,352 786 928 

Sep 1-Sep 30, 2010 5,691 4,677 4,744 6,615 8,728 748 997



TABLE 3.3.2.1.2-1: SUMMARY OF PENNSYLVANIA PROTECTED WATER USE 

CATEGORIES 

Protected 

Description 

Use 

Aquatic Life 

CWF Cold Water Fishes – Maintenance or propagation, or both, of fish species 

including the family Salmonidae and additional flora and fauna which 

are indigenous to a cold water habitat. 

WWF Warm Water Fishes – Maintenance and propagation of fish species and 

additional flora and fauna which are indigenous to a warm water habitat. 

MF Migratory Fishes – Passage, maintenance and propagation of 

anadromous and catadromous fishes and other fishes which ascend to 

flowing waters to complete their life cycle. 

TSF Trout Stocking – Maintenance of stocked trout from February 15 to July 

31 and maintenance and propagation of fish species and additional flora 

and fauna which are indigenous to a warm water habitat. 

Water Supply 

PWS Potable Water Supply – Used by the public as defined by the Federal 

Safe Drinking Water Act, 42 U.S.C.A. § 300F, or by other water users 

that require a permit from the Department under the Pennsylvania Safe 

Drinking Water Act (35 P. S. § § 721.1-721.18), or the act of June 24, 

1939 (P. L. 842, No. 365) (32 P. S. § § 631-641), after conventional 

treatment, for drinking, culinary and other domestic purposes, such as 

inclusion into foods, either directly or indirectly. 

IWS Industrial Water Supply – Use by industry for inclusion into non-food 

products, processing and cooling. 

LWS Livestock Water Supply – Use by livestock and poultry for drinking and 

cleansing. 

AWS Wildlife Water Supply – Use for waterfowl habitat and for drinking and 

cleansing by wildlife. 

IRS Irrigation – Used to supplement precipitation for growing crops. 

Recreation and Fish Consumption 

B Boating – Use of the water for power boating, sail boating, canoeing and 

rowing for recreational purposes when surface water flow or 

impoundment conditions allow. 

F Fishing – Use of the water for the legal taking of fish. For recreation or 

consumption. 

WC Water Contact Sports – Use of the water for swimming and related 

activities. 

E Esthetics – Use of the water as an esthetic setting to recreational pursuits. 

Special Protection 

HQ High Quality Waters 

EV Exceptional Value Waters 

Other 

N Navigation – Use of the water for the commercial transfer and transport 

of persons, animals and goods. 

E-78



TABLE 3.3.2.1.2-2: PENNSYLVANIA’S MAXIMUM WATER TEMPERATURE 

CRITERIA SPECIFIED FOR WARM WATER FISHERIES 

Critical Use Period 

Maximum Temperature 

Criteria (°F) 

January 1-31 40 

February 1-29 40 

March 1-31 46 

April 1-15 52 

April 16-30 58 

May 1-15 64 

May 16-31 72 

June 1-15 80 

June 16-30 84 

July 1-31 87 

August 1-15 87 

August 16-30 87 

September 1-15 84 

September 16-30 78 

October 1-15 72 

October 16-31 66 

November 1-15 58 

November 16-30 50 

December 1-31 42 

TABLE 3.3.2.1.2-3: SUMMARY OF WATER QUALITY DATA COLLECTED FROM 

THE MUDDY RUN PROJECT DISCHARGE FROM 8/8/2006 TO 9/3/2006 

Parameter Minimum Average Maximum 

Dissolved Oxygen (mg/l) 5.2 6.3 9 

Water Temperature (°F) 68.7 80.8 86.7 

pH (standard units) 7.44 7.66 8.03 

Holtwood Dam Flow (cfs) 7,200 18,626 76,200 

Holtwood Dam Water 

Temperature (°F) 

68.5 81.1 86.6 

E-79



3.3.3. Aquatic Resources 

Resident Fish Species 


Muddy Run Power Reservoir 

As many as 47 species of warmwater and coolwater fishes have been identified in Muddy Run 

Power Reservoir, including accidental or introduced species (Table 3.3.3.1-1). Resident fishes 

include: 15 species of minnows (Cyprinidae), 10 species of sunfishes and basses (Centrarchidae), 

five species of perches (Percidae), five species of catfishes (Ictaluridae), four species of suckers 

(Catostomidae), and eight other resident species. Game species include: black bass (smallmouth 

bass, Micropterus dolomieu, and largemouth bass, Micropterus salmoides), walleye, white 

crappie and channel catfish. 

Robbins and Mathur (1976) reported that Muddy Run Power Reservoir was numerically 

dominated by common carp (Cyrinus carpio), channel catfish, quillback (Carpiodes cyprinus), 

white crappie, and spotfin shiner (Cyprinella spilopterus). After its inadvertent introduction to the 

Conowingo Pond in June 1972, young gizzard shad (Dorosoma cepedianum) were collected in 

Muddy Run Power Reservoir in the fall of 1972 (RMC 1979a). Fish reproduction is limited in 

Muddy Run Power Reservoir (RMC 1979a; Heisey et al. 1980) and Snyder (1975) suggested that 

the majority of eggs and young observed in Muddy Run Power Reservoir probably originated in 

upper Conowingo Pond. 

Recruitment to the reservoir is mainly from transfer of larvae from Conowingo Pond during 

Muddy Run Project pumping operations, but may also occur to a lesser extent from Muddy Run 

Recreation Lake via the spillway (RMC 1979a). Successful spawning in Muddy Run Power 

Reservoir is limited due to water level fluctuations. Many of the species common to the region 

(lower Susquehanna River drainage) build nests in the shallows, however, limited nest-building 

by bluegill and pumpkinseed was observed in areas (



912 fish per hectare (369 fish per acre), or 15.9% of all fishes, with channel catfish making up 

90.3% of that proportion. The mean standing crop estimated for 1972-1977 (646 kilogram (kg) 

per hectare [756 pounds per acre]) exceeded the mean standing crop estimate reported by 

Carlander (1955) for numerous conventional reservoirs. Carlander (1955) reported a mean 

standing crop of 378 kg per hectare (337 pounds per acre) and a maximum of 698 kg per hectare 

(623 pounds per acre). In Muddy Run Power Reservoir, carp (69%) dominated the overall 

standing crop estimate and walleye, smallmouth bass, white crappie and channel catfish 

comprised 12.8% of the mean standing crop. 

The creation of the 900 acre Power Reservoir provides additional fish habitat for growth and 

feeding. Growth of smallmouth bass in Muddy Run Power Reservoir improved markedly after 

gizzard shad became abundant (Heisey et al. 1980). 

Muddy Run Recreation Lake 

As many as 36 species of warmwater and coolwater fishes have been identified in Muddy Run 

Recreation Lake, including accidental or introduced species (Table 3.3.3.1-1). Robbins and 

Mathur (1976) identified bluegill and pumpkinseed as the most abundant fishes in Muddy Run 

Recreation Lake during the initial years of impoundment. White crappie, largemouth bass, and 

stocked northern pike, and brook trout were the principal sport fishes. The fish population was 

re-assessed by night electrofishing in 1985. Bluegill, green sunfish, largemouth bass, and 

redbreast sunfish represented 86% of the 22 species collected (RMC 1986). 

A fisheries assessment of Muddy Run Recreation Lake was also performed by the PFBC in 1987. 

PFBC documented a substantial walleye population in Muddy Run Recreation Lake, likely the 

result of fingerling stocking. Walleye stocking was discontinued due to poor return to anglers. 

Fisheries management in Muddy Run Recreation Lake has consisted of stocking trout for put- 

and-take angling and habitat enhancement. The PFBC began stocking rainbow trout each fall in 

the 1980s, which provided additional angling throughout fall and for winter ice fishing. Rainbow 

trout are currently also stocked in February. The PFBC stocked walleye and tiger muskellunge in 

Muddy Run Recreation Lake for a period in the 1980s, and most recently stocked 1,500 channel 

catfish annually during 2001-2005 (PFBC 2012). 

E-83




The fish community of Conowingo Pond is a complex and dynamic ecological system. In 

addition to natural reproduction, fish are recruited to the system from downstream of Conowingo 

Dam (via the EFL), from the Muddy Run Project in generating mode, Conowingo Pond 

tributaries, and from upstream impoundments. Egress of fishes occurs via the Holtwood Fish 

Lift, the Muddy Run Project in pumping mode, and passage over and through Conowingo Dam 

(Normandeau Associates and GSE 2012f). 

The resident fishes of Conowingo Pond include common warm-water species that are found in 

lakes, ponds, and reservoirs from the southeastern US to Canada. The resident fish community 

also reflects intentional and unintentional fish introductions over the last several decades. 

Unintentional introductions include the planktivorous gizzard shad (Dorosoma cepedianum) in 

1972 and, more recently (2002), the predatory flathead catfish (Pylodictis olivaris). Intentional 

introductions include the stocking of hybrid fishes for recreational angling (e.g.,striped bass, 

white bass and tiger muskellunge); neither hybrid is currently stocked in Conowingo Pond, but 

tiger musky are recruited from upriver stocking. American eel (Anguilla rostrata) was stocked 

above Conowingo Dam for years until 1980, but few, if any, individuals are currently present in 

Conowingo Pond. Other introductions have occurred via volitional passage of resident and 

migratory fishes into Conowingo Pond each spring since 1997. As a result, white perch (Morone 

americana) and an apparently residualized population of alewife (Alosa pseudoharengus) are 

now occasionally caught by various gear types. 

Historically, abundance, species composition, and life-history parameters have been monitored to 

document the resident fish community of Conowingo Pond relative to operation of the Muddy 

Run Project and/or PBAPS since 1966. Juvenile and older fishes have been sampled principally 

by seine, bottom trawl, and trap net at selected locations throughout Conowingo Pond. Until 

1979, sampling was continuous on a bi-weekly basis. Beginning in 1980, when PBAPS was 

relieved of sampling requirements by the NRC (RMC 1980), and throughout most of the 

following decade, the number of sampling stations and sampling frequency was reduced (to 

monthly or less) to reflect a maintenance-level program. Renewed systematic sampling relative 

to proposed changes in PBAPS operations (reduced cooling tower use) occurred from 1996 

through 1999, focusing on monthly sampling during June to October in the vicinity of PBAPS. 

E-84



Historical fishery studies in Conowingo Pond have yielded up to 56 species of fish. The principal 

game fish species included: walleye (Sander vitreus), black bass (smallmouth bass (Micropterus 

dolomieu) and largemouth bass (Micropterus salmoides), combined), and channel catfish 

(Ictalurus punctatus). Green sunfish (Lepomis cyanellus), pumpkinseed (Lepomis gibbosus), 

bluegill (Lepomis macrochirus), and white crappie (Pomoxis annularis) were important pan 

fishes. Forage species included gizzard shad, spottail shiner (Notropis hudsonius), spotfin shiner 

(Cyprinella spilopterus), bluntnose minnow (Pimephales notatus), and tessellated darter 

(Etheostoma olmstedi). Gizzard shad, one of the most common species found, may be out- 

competing other species (e.g., white crappie) for food (Normandeau Associates 2000). In 2005, 

more than 305,000 gizzard shad (81% of the total catch) passed into Conowingo Pond via the 

EFL (SRAFRC 2006). In some years, the number of gizzard shad passed into Conowingo Pond 

approaches one million fish. 

A new 5-year sampling program was initiated in 2010 relative to proposed operational changes at 

PBAPS. Monthly fisheries sampling was planned for April through October from 2010-2014 

utilizing three gear types: electrofishing, seine net, and bottom trawl. The study plan also 

includes two winter sample events by electrofishing only. Start-up delays meant that April-June 

2010 fisheries data were not collected; however sampling occurred as planned in July-October 

2010. In 2011, fisheries data were collected in February (electrofishing only) and from April 

through October. 

A summary of the fish species composition for these more recent samplings is shown in Table 

3.3.1.1-2. In 2010 (July – October), a total of 34 species occurred in a total catch of 12,455 fish. 

In 2011 (April – October), a total of 41 species occurred in a total catch of 25,690 fish. As 

typical of results from earlier years, gizzard shad, channel catfish, spotfin shiner, comely shiner, 

and bluegill dominated the overall species composition. Green sunfish, spottail shiner, bluntnose 

minnow, smallmouth bass, and rock bass were also caught in numbers greater than one percent. 

All other species comprised about 5% of the catch. Flathead catfish known to occur in the lower 

Susquehanna River drainage since 2002 represented a new species addition within a formal 

sampling program. 

Migratory Fish Species 


E-85



Anadromous fishes are those fish species that spend all or part of their adult life in salt water and 

return to freshwater streams and rivers to spawn. Conversely, catadromous fishes are species that 

reproduce in the sea but spend most of their lives in freshwater, estuarine, or inshore marine 

waters. Historically, adult anadromous species, primarily alewife (Alosa pseudoharengus), 

blueback herring (Alosa aestivalis), and American shad have been passed into Conowingo Pond 

via the Eastern Fish Lift (EFL) at Conowingo Dam. Currently, adult American shad are the only 

one of these anadromous species to consistently migrate upstream past the Muddy Run Project on 

a regular basis each spring. Wild juvenile American shad or juveniles that are stocked as fry and 

reared in upstream areas (i.e., above Holtwood Dam) emigrate downstream past the Muddy Run 

Project in the fall. During the juvenile stage (elver and yellow), the few catadromous American 

eel that are able to reach Conowingo Pond may migrate upstream through Conowingo Pond and 

past the Muddy Run Project in the spring; few yellow eel remain in Conowingo Pond. As adult 

eels begin to sexually mature, they migrate downstream in the fall as they return to the sea. 

However, because few juvenile eels migrate past Conowingo Dam, few adult eels reside in the 

Susquehanna River upstream of the Muddy Run Project. Thus, the lower reservoir for the Muddy 

Run Project currently serves chiefly as a migration corridor for both juvenile and adult American 

shad and a low number of juvenile and adult American eels 15 . 

Entrainment, Impingement and Mortality 

In 2010, Exelon investigated the potential for fish to be entrained at Muddy Run powerhouse 

intakes in the Project (Normandeau Associates and GSE 2012e). The objectives of the study 

were to: 1) evaluate the potential for entrainment and impingement of six resident fish species 

and two diadromous fish species at the Muddy Run Project, and 2) evaluate survival probabilities 

of the eight fish species at the Project, taking into account site-specific data such as turbine type, 

rotational speed (rpm), and size of entrained fish. 

The goal of the study was to assess the likelihood of entrainment into Project intakes and if so, 

whether it is likely that entrainment would have a significant effect on fish populations. To 

15 The USFWS has initiated a status review for the American eel as a result of a 90-day finding on the 

Council for Endangered Species Act Reliability’s petition to list the American eel as threatened under the 

authority of the Endangered Species Act. The Service published a notice in the Federal Register on Sept. 

29, 2011. The notice commenced a 60-day information request period, which closed Nov. 28, 2011. Before 

making a 12-month finding on whether listing the eel is warranted, the Service must gather and analyze the 

new information received during this period. In this review, the Service must find that the eel warrants 

listing in order to propose that it receive federal protection. 

E-86



achieve this goal, a fish entrainment evaluation was conducted utilizing historic data from Muddy 

Run Power Reservoir and Conowingo Pond, existing literature, life history information, and data 

on fish entrainment at other hydroelectric projects for eight species of management interest at the 

Muddy Run Project. The fish species considered in the evaluation were those identified by 

Exelon and Project stakeholders as important management species and included both resident 

fish: bluegill, channel catfish, rock bass, smallmouth bass, walleye and white crappie; and 

diadromous fish: American eel and American shad. 

The evaluation also considered the potential for fish survival in the event of entrainment into and 

through the Project pump/turbines. The survival assessment was also based on an extensive 

review of literature and existing data and considered the important physical characteristics of the 

units as well as the biological characteristics of the eight fish species. Some of the important 

factors considered in this portion of the assessment included turbine type, turbine speed and 

intake characteristics. The results of Exelon’s study are summarized below. 

Resident Fish Species 

The life history and behavior of the six resident fish were examined to assess the potential for 

entrainment of fish from Muddy Run Power Reservoir during Project generation. Many of the six 

resident species are primarily littoral zone fishes. While these species are found in Muddy Run 

Power Reservoir, few individuals are expected to be found in the 1000-ft long concrete intake 

channel between the Muddy Run Power Reservoir and the intake structures at the end of the 

intake channel. The channel lacks the shallow, in-water cover, and sandy or rocky littoral zone 

substrate preferred by these species. The physical distance of the fish throughout the Reservoir 

from the intake structures reduces their exposure to entrainment. Channel catfish and walleye, 

particularly large-sized adults, may be found in the intake channel; however, they are generally 

capable of avoiding flow velocities encountered about 200 feet from the intake cylinders when 

the Project is generating. 

Certain operational factors are likely to result in increased entrainment rates including: reservoir 

drawdown of up to 50 feet on a regular basis and a high hydraulic capacity. The reduced reservoir 

volume places the abundant forage species (primarily gizzard shad) and their predators at a 

greater risk of entrainment because they are more likely to be in the intake canal. Similarly some 

individuals of the littoral zone species in the Reservoir near the mouth of the intake channel may 

also be at some greater risk of entrainment. However, because the turbines are large and rotate 

E-87



slowly, survival rates of the small fish that are most likely to be entrained are expected to be high 

(greater than 95%). 

The life history and behavior of the six resident fish were also examined to assess the potential 

for entrainment of fish from Conowingo Pond during Project pumping. The Muddy Run Project 

intake structure in Conowingo Pond is perpendicular to river flow and suitable littoral habitat in 

the area of the intakes is limited. This reduces the entrainment potential for juvenile and adult 

stages of littoral zone species that prefer shallow habitat associated with cover. Most of the six 

resident species have swim speeds sufficient to overcome intake flow velocities (0.5 to 3.0 fps) 

measured about six feet in front of the intake structure during pump-back operations. 

Certain operational factors suggest entrainment rates are likely to be higher during pump-back 

operations than during generation. Primarily, flow velocities immediately in front of the trash 

rack are slightly higher, though velocities dissipate somewhat away from the intakes (i.e., in the 

river channel). The lack of significant littoral habitat near the Project and deep set intake 

structures (37.8 ft below full pond elevation) moderate these higher velocities. 

For both generation and pumping, egg and larval fish stages are more likely to be entrained than 

juvenile and adult fish. These stages are largely passive with no ability to avoid the intake 

currents. This effect would be greater for species with pelagic eggs and larvae than for species 

that maintain nests (e.g., bluegill, bass). Of the six resident species, effects of entrainment are 

anticipated to be highest for juvenile and adult channel catfish during both generation and pump- 

back. Channel catfish are a resident, benthic species known to reside near the intake structures in 

Muddy Run Intake Channel and Conowingo Pond. The swim speed of channel catfish is 

sufficient to escape flow velocities at the intake structure during generation but not near the 

intake trash rack during pump-back. The other resident species have relatively low entertainment 

potential due to swim speeds in excess of intake flow velocity or habitat preferences that 

generally keep them at a distance from the intake structures. 

A qualitative assessment of overall survival potential was developed from data in the EPRI 

database, results from additional survival studies, and survival estimates calculated using the 

Franke et al. (1997) model. Quantitative data from the three data sets were converted to a 

qualitative ranking system where: 

High (H) = 100-95% 

Moderate-High (MH) = 95-90% 

E-88



Moderate (M) = 90-85% 

Low-Moderate (LM) = 85-80% 

Low (L) =



Migratory Fish Species 

The two species considered in the migratory fish evaluation were American eel and American 

shad, which are migratory species that pass through Conowingo Pond during their life cycle. 

Their entrainment potential through the Muddy Run Project is dependent upon their proximity to 

the intake structure and is limited to periods of pumping (approximately 2200 – 0500 hrs). In 

addition to literature review, entrainment potential for adult eels and juvenile and adult shad was 

evaluated with studies in Conowingo Pond. 

Adult American eel 

Although an established run of emigrating adult or silver American eel is lacking at present, it is 

expected when present, that they may emigrate downstream through Conowingo Pond primarily 

in October and November. 

Exelon conducted a site-specific study to assess entrainment potential for downstream migrating 

adult American eel at Muddy Run (Normandeau Associates and GSE 2012c). The calculated 

study entrainment rate inclusive of all telemetered eels that passed Muddy Run during all 

operating conditions (pumping, generating, and idle mode) was 7.2%. A pumping entrainment 

rate of 26.3% was estimated for telemetered eels that encountered the zone of influence at the 

Muddy Run Project during pumping mode. When this pumping entrainment rate is integrated 

into a model that includes the proportion of eels migrating when Muddy Run is typically pumping 

(from 2200 to and including 0500 hrs), the percentage of eels present near the intake structure, it 

is estimated that approximately 7% of the emigrating eels are likely to be entrained. 

The survival potential for adult American eel entrained at the Project is estimated to be moderate 

to low (90% to greater than 80%) and is dependent on the length of the fish entrained (i.e., large 

fish generally have lower survival rates). 

Juvenile American eel 

Yellow or juvenile eels may find suitable habitat and reside in Conowingo Pond until making 

their downstream migration as an adult. Yellow eel have a limited home range, suggesting that 

only those yellow eel resident in the vicinity of the intake structure are susceptible to entrainment. 

Exelon’s study concluded that the overall entrainment rating for juvenile American eel was low- 

moderate based on literature estimates (Normandeau Associates and GSE 2012e). Currently, few 

juvenile eels are present in Conowingo Pond. 

E-90



Adult American shad 

American shad are surface oriented and only present in the vicinity of the intake structure for a 

short period of time as they migrate through Conowingo Pond in the spring (April-June). The 

burst swim speed 17 of adult American shad (11.5-13.0 feet per second) is greater than the flow 

velocity (4.19 fps) at the intake structure. 

Exelon conducted site-specific studies to assess entrainment potential and near-field passage for 

adult American shad at Muddy Run (Normandeau Associates and GSE 2012g). The analysis 

included radio telemetry data collected in 2008, as well as an examination of previous radio 

telemetry studies conducted in 1989 and 2001. 

The 2001 and 2008 telemetry data provided an adult shad entrainment rate during Muddy Run 

pumping operations from April to June. The 2001 study reported an estimated entrainment rate 

between 3.8% (7 of 183) and 5.1% (7 of 136), depending on how the number of fish available to 

be entrained was calculated. The 2008 study estimated an entrainment rate of approximately 

3.6% (9 of 248). Based on the prevailing water temperatures (> 70 °F) and dates (late May-early 

June) of entrainment, most entrained shad were assumed to be post-spawned fish. 

Exelon’s literature review concluded that the entrainment potential of adult American shad was 

estimated to be low based on literature estimates (Normandeau Associates and GSE 2012e). The 

literature review also suggested the survival potential for entrained adult American shad is 

expected to be moderate to low (90-



all operating conditions (pumping, generating, and idle mode) was 9.4%. A pumping entrainment 

rate of 22.6% was estimated for telemetered shad that encountered the zone of influence at 

Muddy Run during pumping mode. However, when the pumping entrainment rate is integrated to 

account for both the typical pumping schedule at Muddy Run and the known behavioral 

emigration pattern of juvenile American shad (peak emigration times between 1700-2200 hrs), it 

is estimated that approximately 2.9% to 6.6% of emigrating shad are likely entrained. The study 

results also indicated that the proportion of shad entrained at Muddy Run appears to be related to 

the number of units pumping. The majority of juvenile shad were entrained when six or more 

units were pumping. 

Exelon’s literature review concluded that the entrainment potential of juvenile American shad is 

expected to be low-moderate based on literature based estimates (Normandeau Associates and 

GSE 2012e). The literature also suggested that the survival potential for entrained juvenile 

American shad is expected to be high (100-95%). 

Alewife and Blueback Herring 

Alewife and blueback herring were not identified as target species for the study, but the effects 

likely would be similar to American shad based on similar migratory behaviors. 

In-River Migratory Fish Passage Impediments 

Thermal Barriers 

Exelon conducted a study to determine the impact of an upstream shift in the PBAPS cooling 

water discharge thermal plume, due to Muddy Run pumping operations, on the availability of a 

migration corridor for fishes moving through Conowingo Pond (Normandeau Associates and 

GSE 2012h). 

Adult pre-spawned American shad migrate upstream through Conowingo Pond in April and May. 

Post-spawned shad emigrate in late May to July, and juvenile shad emigrate primarily in October 

and November. Since migration timing of river herring overlaps that of American shad to a large 

extent, conclusions drawn for American shad also apply to these species. 

The hydrologic conditions that are conducive for an upstream shift in the thermal plume were 

identified using a 3-D time varying hydraulic- thermal model (Generalized Environmental 

Modeling for Surfacewaters Systems or GEMMS ®) developed by ERM, Inc... The model 

indicated that an upstream dispersion of the thermal plume (a rise (∆T) in surface water 

E-92



temperature of at least 1°F at the PBAPS intake) can occur at river flows of less than or equal to 

12,500 cfs coincident with sustained pumping operations (> approximately 28,000 cfs) for 12h 

(typical pumping time at present is 7-8 h)) of the Muddy Run Project and a cessation or reduction 

of outflow at Conowingo Dam. 

The probability of co-occurrence of river flows equal to or less than 12,500 cfs and peak 

migration time was used to assess whether hydrological conditions exist that are conducive to 

upstream dispersal of the PBAPS thermal plume when species of interest are migrating through 

Conowingo Pond. The probability of occurrence at flows less than or equal to 12,500 cfs for pre- 

spawned shad during migration in Conowingo Pond (April – May) is 0% in April and less than 

0.6% in May. Thus, the potential for interactive effects of the two power stations on upstream 

migrating adult American shad is concluded to be minor. 

The migration of post-spawned adult American shad within Conowingo Pond also appeared 

unimpeded. Results of a radio tagging study of post-spawned shad in 1988 indicated that 75% of 

the shad freely migrated upstream and downstream past the Muddy Run Project. River flows 

during the study ranged between 4,300 and 20,800 cfs. Systematic weekly tracking of radio 

tagged American shad in May through August 2010 (fish tagged at Safe Harbor and those passed 

upstream from Conowingo EFL were available for monitoring) corroborated earlier findings. 

Tagged fish did not change movement direction even though river flows less than 10,000 cfs 

occurred 100% of the time in July 2010. Historically, river flows less than 10,000 cfs occurred 

36% of the time in July. 

The risk of exposure of juvenile shad to interactive effects of the two power stations appears to be 

low as well. The peak outmigration of juvenile shad primarily occurs at water temperatures 

between 50 and 60°F in October and November. Although historically river flows less than or 

equal to 12,500 cfs occurred 53.5% of the time in October and 24% of the time in November, 

they co-occurred with water temperature of 50 to 60°F approximately 13.4% of the time in 

October and 14% of the time in November. 

Known active avoidance responses of juvenile shad to lethal temperatures and the ability to 

traverse heated effluent provided evidence that young shad would be able to traverse Conowingo 

Pond. The estimated upper avoidance temperature of juvenile American shad (Moss 1970; Marcy 

et al. 1976; RMC 1979) is reported at greater than or equal to 86.0° F (30.0°C). In Conowingo 

Pond at an ambient water temperature of 60.0°F (15.6°C), PBAPS discharge temperature would 

E-93



be 82.0°F (27.8°C, with the designed rise (∆T) of 22.0°F or 12.2°C). Since the thermal discharge 

is released via a submerged jet at 5-7 fps, heat dissipation is fairly rapid (Elder et al. 1973). As a 

result, the thermal plume affects the top 5 to 15 ft of the water column primarily along the 

western shoreline and downstream to western and mid-pond areas to the Pennsylvania/Maryland 

state line (Normandeau Associates 1999). Virtually the entire pond is less than 86 °F (30.0 °C) 

and is available for juvenile shad emigration. 

Juvenile American eel (elvers), when present in Conowingo Pond, could be subjected to similar 

hydrologic conditions encountered by post spawned adult American shad. Therefore, the 

interactive effects of the two power stations on juvenile eels should be minimal. 

While an established run of emigrating adult American eel through Conowingo Pond does not 

currently exist, based on a literature review (e.g. EPRI 2001), it is likely that adult American eel 

would emigrate primarily from October through November. The onset of migration generally 

coincides with freshets at water temperatures less than 70 °F. American eels have been 

acclimated to water temperatures ranging from 42.8°F to 86.0°F in laboratory experiments (Barila 

and Stauffer 1979). Based on this run timing and temperature tolerance, American eel adults 

could be subjected to similar hydrological conditions as juvenile American shad. As in the case 

of juvenile shad, the interactive effects of the two power stations on migrating eel should be 

minimal. This conclusion is supported by a report by the USFWS (2012) that found that most 

(89.8%) of adult eels that were tagged above the Muddy Run Project and continued migrating 

through Conowingo Pond successfully passed PBAPS. 

Velocity Barriers 

Exelon collected water velocity data in 2010 in the area of the Muddy Run tailrace to investigate 

potential impacts related to Muddy Run operations on migratory fish (Normandeau Associates 

and GSE 2012g). Water velocity profile data collected when the Holtwood Project was releasing 

between 27,000 cfs and 30,000 cfs, Muddy Run was releasing between 26,000 cfs and 32,000 cfs 

and Conowingo Pond varied between El. 107.7 ft and 110.5 ft, indicates that 1) the highest water 

velocities are close to the eastern shoreline; 2) there are substantial areas along each transect 

where velocities are approximately 2.4 fps or less and; 3) no observed velocities exceeded 5.5 fps. 

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Areas immediately downstream of the Muddy Run powerhouse have the highest overall 

velocities, but there are still substantial areas where the velocity is approximately 2.4 fps or less. 

Given the American shad’s sustained 18 and prolonged 19 swim speed (2.4 fps and 7 fps, 

respectively), there are substantial areas within the tailrace that provide a zone through which 

adult shad can migrate upstream without exceeding the sustained swim speed, and there are no 

areas that exceed shad’s prolonged swim speed. 

In addition, radio telemetry data collected in 2008 were analyzed, along with previous radio 

telemetry studies conducted in 1989 and 2001 (Normandeau Associates and GSE 2012g). Based 

on the number of adult American shad detected in the immediate vicinity of Muddy Run, the 

near-field passage rate (the number of fish detected at a location upstream of Muddy Run divided 

by the total number of fish that were detected at or downstream of Muddy Run) varied from 91% 

in 1989 to 80% in 2001 and 84.5% in 2008. 

Aquatic Habitat 


Aquatic habitat within Muddy Run Power Reservoir generally consists of a wide and gently 

sloping non-vegetated shoreline that is subject to daily water level fluctuation. Shoreline 

substrates are primarily unweathered bedrock covered with a veneer of fragmented weathered 

bedrock, colluvium and alluvium. Bedrock outcroppings and overhangs are also common features 

along the shoreline littoral areas. 


Aquatic habitat within Conowingo Pond is described in the Conowingo Hydroelectric Project 

License Application, Exhibit E, Section 3.3.3.1.7, and incorporated into this document by 

reference. 

Recreational Fishery 

Muddy Run Recreation Lake 

18 

Sustained swim speed is that which can be maintained for an indefinite period (longer than 200 minutes) 

and does not involve fatigue. 

19 

Prolonged swim speed can last between 15 seconds and 200 minutes and if maintained will end in 

fatigue. 

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Angling in the Muddy Run Project upper reservoir is entirely focused in areas within the Muddy 

Run Recreation Lake, which was opened for fishing in 1969. The lake offers angling 

opportunities for bluegill and other sunfish, largemouth bass, white and black crappie, yellow 

perch, and walleye, as well as other warm water species (Robbins and Mathur 1976). Northern 

pike (Esox lucius) yearlings were introduced into Muddy Run Recreation Lake by the PFBC in 

1969 (Robbins and Mathur 1976). Muddy Run Recreation Lake is also included in the PFBC’s 

Early Season Trout-Stocked Waters Program, providing a put-and-take trout fishery. Angling 

access is provided along the shoreline and from boats. A boat rental facility run by the park 

operator and a hard surface launch ramp (fee) with courtesy dock for private craft are available. 

Gas-powered outboard motors are not permitted. The entire Recreation Lake shoreline perimeter 

is available for fishing. 

During a creel survey in 1972, when limited fishing access to Muddy Run Power Reservoir was 

opened, 17 species were caught by anglers. Channel catfish, white crappie, common carp, and 

smallmouth bass dominated the catch (RMC 1979a). Northern pike were also caught, despite no 

stocking of this species in the Muddy Run Power Reservoir. Since northern pike were stocked in 

the Recreation Lake, it is assumed that these fish entered the Muddy Run Power Reservoir from 

the Lake via the spillway (RMC 1979a). Anglers released the majority of channel catfish and 

smallmouth bass due to small size or being caught out of season. However, 79 percent of all 

black crappie (Pomoxis nigromaculatus) and white crappie caught were kept by the fishermen 

(RMC 1979a). 

A temporally focused creel survey in spring 1987 documented the intense interest in the crappie 

fishery in Muddy Run Power Reservoir (RMC 1988). Predominantly local anglers fishing near 

the Muddy Run Recreation Lake spillway harvested an estimated 2,880 white crappie, most of 

which occurred over a three-week period. The white crappies harvested were large. Mean total 

length (TL) exceeded 11 inches, and more than 20% of the harvest exceeded 12 inches TL. 

Channel catfish and yellow perch were also caught. 

Creel surveys of the Muddy Run Recreation Lake in the mid-1980s focused on annually stocked 

brook trout (Salvelinus fontinalis), crappie, and black bass species (i.e., smallmouth bass, 

Micropterus dolomieu, and largemouth bass, Micropterus salmoides, combined). Most brook 

trout were harvested in spring. Catch and harvest during summer and fall of 1985 and 1987 

comprised mainly bluegill and other sunfishes, white crappie, largemouth bass, and yellow perch 

(RMC 1986; 1988). A few walleye and tiger muskellunge, both stocked species, were also 

E-96



caught. One quarter of the anglers at Muddy Run Recreation Lake in 1987 were also camping in 

Muddy Run Park. 

A creel survey conducted from April through November 2010 (Normandeau Associates and GSE 

2012i) included both aerial counts and ground surveys of boat and shoreline anglers at the Muddy 

Run Recreation Lake. Anglers caught an estimated 15,662 fish. Sunfish species (Lepomis spp.) 

plus rock bass (Ambloplites rupestris) accounted for 54.2% of the fish caught by anglers. 

Length measurements of fish harvested by boat anglers were obtained from 127 fish representing 

eight species or species groups. Rainbow trout accounted for 52.0% of all harvested fish 

measured and ranged from 7 to 20 inches long. Crappie (Pomoxis spp.) ranged from 7 to 12 

inches long; 65% of the crappie were white crappie (Pomoxis annularis). Length measurements 

were obtained from 163 fish of five species harvested by shore anglers. Rainbow trout dominated 

the measured harvest from shore; lengths ranged from 9 to 21 inches. 

Anglers also provided a measured or estimated length (to the nearest inch) of numerous fish 

released back into Muddy Run Recreation Lake. Boat anglers provided measurements for 12 

species and three species groups released totaling 636 fish. Black bass represented 73.8% of all 

fish measured and released; with 93% being largemouth bass. Over 80% of the released 

largemouth bass were reported as legal (≥12 inches) to harvest. Crappie up to 14 inches long 

were measured and released by boat anglers. Shore anglers released 228 fish following 

measurement; most (44%) were rainbow trout that measured up to 16 inches long. 

The results of the 2010 creel surveys were similar to that of earlier surveys in 1985 and 1987 in 

the time period that particular species were sought, preference of species sought, species 

harvested and angler demographics. The estimated angler hours in 2010 were approximately 56% 

of that in 1985, much like the June to October time period in 1987 that was compared to the 1985 

survey. The preference of species sought was trout and black bass in all three surveys. The 

directed catch and harvest rates are generally comparable in 1985 and 2010 due to comparable 

time period that the two surveys were conducted. The demographics (mid-60%) of anglers that 

fished the Muddy Run Recreation Lake were residents of Lancaster County, PA in 1985 and in 

2010 (Table 3.3.3.1-3). 


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The recreational fishery of the Conowingo Pond can be described by the results of a creel survey 

conducted by Exelon from March 1, 2010 through February 28, 2011 (Normandeau Associates 

and GSE 2012j). Surveys conducted during the spring, summer, and fall (March 1 through 

November 30, 2010) provided the most useful information. Count efforts during 42 scheduled 

weekly aerial flights recorded 497 actively fishing boats and 189 shore anglers. Additionally, 

boat and shore anglers were interviewed at 13 access points ranging from the Norman Wood 

Bridge (PA Rt. 372) just below Holtwood Dam to the Conowingo Dam. Interviews were used for 

a total of 646 boat anglers representing 365 parties, as well as 152 shore anglers representing 71 

parties. 

Although “casual” anglers not seeking a particular species accounted for 80% of all shore anglers 

interviewed, boat fishing pressure was largely directed toward black bass. Over half of the boat 

anglers interviewed during the summer and fall were seeking black bass, with weekend fishing 

pressure dominating. 

Of the estimated 18,466 black bass caught (41% of all fish caught), only 79 were estimated to 

have been harvested. Instead, catfish (flathead and channel) were more likely to be harvested, 

with an estimated 2,147 of 12,428 catfish caught being harvested (80% of all fish harvested). 

None of the estimated 11,000 sunfish and crappie species caught were found to have been 

harvested. The retention rate of the total 44,526 fish caught by boat (5.3%) and shore (8.9%) 

anglers was 6.0% combined. Table 3.3.3.1-4 shows a breakdown of species caught and harvested 

by boat and shore anglers combined on Conowingo Pond in the spring, summer, and fall of 2010. 

The winter portion of the Conowingo Pond creel survey (December 1, 2010 through February 28, 

2011) did not generate any expanded statistics due to a lack of angling pressure. Winter count 

efforts during 13 aerial flights recorded only six actively fishing boats and two shore anglers. A 

total of 22 boat anglers representing 13 parties were interviewed. Six fish species or species 

groups were sought, with the largest proportion of anglers (36.4%) seeking largemouth bass. 

The primary purposes of the winter study were to estimate angling pressure at PBAPS warm- 

water discharge and determine the opportunity to ice fish in the tributaries like Broad Creek and 

Funk’s Run Pond. All boat anglers reported to be fishing the thermal discharge. Although the 

winter of 2010-2011 produced ice on Conowingo Pond, it may have been too thin for many shore 

anglers to utilize, while still creating an obstacle for boat anglers trying to launch and navigate to 

the PBAPS discharge. Ice started in the tributaries and coves in early December, and the PBAPS 

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boat ramp was iced in by mid-December. In January, ice fishing holes were observed at Funk’s 

Run Pond and Broad Creek. By mid-February, the Conowingo Pond was free of ice except for a 

small portion of Funk’s Run Pond. 

Benthic Macroinvertebrates 


The benthos of Muddy Run Power Reservoir is limited to the profundal zone due to the 

intermittent generation and pumping cycle that alternately exposes and inundates sediment above 

the minimum pond level (RMC 1979a). Studies conducted between 1968 and 1976 identified 21 

taxa, 14 of which belong to the Tubificidae (tubificid worm) and Chironomidae (midge) families 

(Table 3.3.3.1-5). The benthic community in Muddy Run Power Reservoir was found to be far 

less diverse than that in Conowingo Pond and was dominated by the worm Limnodrilus 

hoffmeisteri. 

Succession in the benthic invertebrate community since the creation of Muddy Run Power 

Reservoir may have contributed to a change in the species composition; populations of 

Polypedilum halterale and Tanytarsus spp. declined and L. hoffmeisteri populations increased 

dramatically (RMC 1979a). The benthic community in the Muddy Run Recreation Lake is 

similar to that of the Muddy Run Power Reservoir. 


Benthic invertebrate samples obtained from various locations in Conowingo Pond between 1967 

and 1984 yielded 61 taxa (Normandeau Associates 2001). Primary components of the benthic 

community were oligochaetes and chironomids, with the tubificid worm Limnodrilus 

hoffmeisteri, the midge Procladius sp., the phantom midge Chaoborus punctipennis, the midge 

Chironomus attenuatus, the midge Coelotanypus consinnus, and the tubificid worm Ilyiodrilus 

templetoni comprising 94-98 percent of the total abundance in various years. The generally 

sparse invertebrate community in the lower two-thirds of the Conowingo Pond may be due to 

unfavorable substrate conditions (sand-coal fines and silt) (Normandeau 2001). Burrowing 

mayflies such as Hexagenia limbata in this reach provide a significant food resource for species 

such as smallmouth bass, white crappie, and channel catfish. 

Nuisance Macroinvertebrate Species 

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The Asiatic clam (Corbicula fluminea) is a small bivalve native to southeastern Asia often found 

at high densities in clear, well-oxygenated waters. Since the mid-1980s, this species has rapidly 

colonized the lower Susquehanna River. This species was detected in the Muddy Run Power 

Reservoir in April 1985. 

Another non-indigenous bivalve, the zebra mussel (Dreissena polymorpha), is a small, fingernail- 

sized mussel native to the Caspian Sea region of Asia. Zebra mussels have been found in the 

upper Susquehanna River drainage (Kazyak et al. 2005). Zebra mussels were detected in Muddy 

Run Power Reservoir in November 2008, shortly after their initial discovery in Conowingo Pond 

in late October. Zebra mussels found along the Muddy Run shoreline were all dead animals (shell 

only). Subsequently, zebra mussel veligers were documented during 2009 and 2010 in the intake 

canal at PBAPS. Biomonitoring at Conowingo Dam in 2010 did not detect any zebra mussels. 

Phytoplankton and Zooplankton 

Pelagic algae, or phytoplankton, represent the base of the aquatic food chain, converting sunlight 

into biomass and providing a food source for zooplankton and small invertebrates. Zooplankton 

are grazers of phytoplankton and are the primary food source for zooplanktivorous fish and 

invertebrates. 


The phytoplankton community in Muddy Run Power Reservoir was characterized during studies 

conducted from 1966 to 1978 (RMC 1979a). A total of 35 genera of algae were identified in the 

reservoir, the most common of which were the green algae Pandorina spp., Pleodorina spp., 

Pediastrum spp., the diatom Melosira spp., and the blue-green algae Anacystis spp., 

Gomphosphaeria spp., and Anabaena spp. (Table 3.3.3.1-6). Green algae and diatoms were the 

most abundant taxa in the reservoir annually, and peak abundance was recorded from late-spring 

through late-summer (RMC 1979a). The phytoplanktonic community in Muddy Run Power 

Reservoir is less diverse than that in Conowingo Pond. 

A total of 46 taxa of zooplankton were collected from Muddy Run Power Reservoir during 

sampling of this water body between 1967 and 1976. Dominant zooplankters, comprising greater 

than 90 percent of the collections, included the water fleas Diaphanosoma leuchtenbergianum, 

Daphnia spp., and Bosmina longirostris, the cyclopoid copepod Cyclops vernalis, cyclopoid 

copepodids, and copepod nauplii (Table 3.3.3.1-7). The density of the zooplankton community 

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in Muddy Run Power Reservoir varied seasonally, with the highest densities reported for the time 

period between late spring and mid-fall (RMC 1979a). 


The Conowingo Pond plankton community was characterized during ecological studies 

conducted at various locations in the Pond from 1966 through 1978 (RMC 1979a). A total of 44 

genera of algae were identified in Conowingo Pond in the vicinity of the Muddy Run Project, 

including the most common genera observed: Pandorina, Pleodorina, Pediastrum (green algae), 

Melosira (diatom), and Anacystis, Gomphosphaeria, and Anabaena (blue-green algae). Diatoms 

comprised 50 percent of the phytoplankton population in Conowingo Pond. Green algae were 

common in August and September, brown algae in October, diatoms in June and July, and blue- 

green algae in September. 

The zooplankton community in Conowingo Pond was evaluated in studies conducted between 

1966 and 1978 (RMC 1979a). The community was comprised of 53 species, and was 

numerically dominated by six taxa: the water fleas Diaphanosoma leuchtenbergianum, Daphnia 

spp., and Bosmina longirostris, the cyclopoid copepod Cyclops vernalis, cyclopoid copepodids, 

and general copepod nauplii. The mean monthly density of these dominant taxa was greatest 

between the months of June and September, with densities exceeding 100 individuals/L (RMC 

1979a). Densities averaged less than three individuals/L from November through May. 


Effects of Entrainment and Impingement 

Resident Fish 

For Exelon’s proposed alternative, the overall entrainment impacts on the Power Reservoir’s 

resident fishes is expected to be low-moderate during generation, and not result in significant 

impacts to resident fish populations. 

Resident fish are not likely to be in the area of the Project’s concrete intake channel, since it lacks 

the shallow, in-water cover, and sandy or rocky littoral zone substrate preferred by most of these 

species. Adult channel catfish and walleye may be found in the intake channel; however, they are 

generally capable of avoiding flow velocities near the intake cylinders during generation. 

However, the reduced reservoir volume during reservoir drawdown may lead to some 

entrainment of resident species. 

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During pumping operations the impact to fishes due to entrainment is expected to be moderate 

under Exelon’s proposed alternative, since the Project intake structure in Conowingo Pond is 

perpendicular to river flow and suitable littoral habitat in the area of the intakes is limited. In 

addition, most of the target species have swim speeds sufficient to overcome intake flow 

velocities present during pumping operations. 

Entrainment is expected to be highest for juvenile and adult channel catfish during both 

generation and pumping operations. Channel catfish are a bottom dwelling species that may 

reside near the intake structures in Muddy Run intake channel and Conowingo Pond. The swim 

speed of channel catfish is sufficient to escape flow velocities at the intake structure during 

generation but not velocities near the intake trash rack during pumping. 

Fish impingement would be unlikely for most target species during generation and pumping 

given the wide bar rack spacing and relatively deep intakes. Fish lacking the swimming ability to 

avoid the intakes would be expected to pass through the bar racks and not be impinged upon 

them. 

Entrainment survival potential under Exelon’s proposed alternative for juvenile stages of all of 

the target species is expected to be High to Moderate-High (100-90%). Adult bluegill, rock bass, 

smallmouth bass, and white crappie are expected to have High to Moderate-High (100-90%) 

survival. Survival for adult channel catfish and walleye is expected to be Moderate to Low- 

Moderate (90-80%). 

Migratory Fish 

American Shad and River Herring 

For Exelon’s proposed alternative, entrainment rates for adult American shad, during the spring 

migration season (Apr-Jun), are expected to be approximately 3.6 to 5.1%. The survival potential 

for any entrained adult American shad is expected to be moderate to low (90-

American Eel 



For Exelon’s proposed alternative, entrainment rates for adult American eel, during the primary 

fall migration season (Oct-Nov) are expected to be approximately 7%. The survival potential for 

adult American eel entrained at the Project is estimated to be moderate to low (90-



would occur less than 14% of the time. In addition, under the proposed alternative water 

temperatures influenced by PBAPS are not expected to exceed avoidance temperature levels 

(86°F) for juvenile shad (Moss 1970; Marcy et al. 1976; RMC 1979) during the migration season, 

leaving a migration corridor through Conowingo Pond. 

As part of the proposed alternative for the Conowingo Project relicensing, Exelon is proposing to 

work with other licensees on the Susquehanna River to implement both an upstream and 

downstream trap-and -transport program to provide American eel passage between Conowingo 

and York Haven Dams. This program would minimize impacts related to PBAPS thermal plume 

on upstream and downstream passage of American eel as the eels would not be exposed to the 

plume. 

Exelon anticipates that the cost of the downstream trap and transport program would be shared 

among the licensees of the four dams the eels would be required to pass. Additional background 

and research information will need to be gathered to further refine aspects of the downstream trap 

and transport program before its implementation. 

Velocity Barriers 

Near-field passage of adult American shad at the Project is expected to range from approximately 

80% to 91% during the migration season. Water velocity data measured in the tailrace indicate 

that there are substantial areas where velocities are approximately 2.4 fps or less and maximum 

velocities do not exceed 5.5 fps. The adult American shad’s sustained and prolonged swim 

speeds are 2.4 fps and 7 fps, respectively. Under the proposed alternative, substantial areas 

within the tailrace are expected to be present to provide for a zone of upstream passage. 

Effects on Invasive Zebra Mussels and Other Exotics 

The Asiatic clam and zebra mussels have been detected in low densities within the Muddy Run 

Power Reservoir, as well as within areas of Conowingo Pond. In addition, a widely distributed 

and low density population of adult zebra mussels is present in upstream and downstream 

portions of the Susquehanna River; it is unclear whether this represents the start of a population 

explosion or the maximum extent of the zebra mussel colonization. The impounded waters 

upstream of Conowingo Dam contain sufficient habitat and provide appropriate flow and 

environmental conditions throughout most of the year to allow establishment of viable zebra 

mussel populations (Normandeau Associates 1995 and 2002). 

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Under Exelon’s proposed alternative, zebra mussel settlement within Muddy Run Power 

Reservoir could continue from veligers spawned in upstream impoundments/areas of the river and 

transported to Muddy Run Power Reservoir during pumping operations. Colonization and 

infestation could potentially impact any structure or system components that come in contact with 

raw river water, and make them susceptible to mussel settlement/fouling. 


CEQ regulations define ‘cumulative effects’ as “the impact on the environment that results from 

the incremental impact of the action when added to other past, present, and reasonably 

foreseeable future actions regardless of what agency (Federal or non-Federal) or person 


For this analysis, the action is the relicensing and continued operation of the Muddy Run Project. 

The cumulatively affected resource is fish/aquatic resources. The geographic scope for resident 

and diadromous fish is defined by FERC in their Revised Scoping Document as the entire 

Susquehanna River watershed and the upper Chesapeake Bay habitat resources. The temporal 

scope of this analysis includes a discussion of the past, present, and reasonably foreseeable future 

actions, and their effects on the resource based on a new license term. 

The potential impact of the Project is associated with whether the continued operation of the 

Muddy Run Project affects resident and migratory fish populations and associated habitat of the 

upper Chesapeake Bay and the Lower Susquehanna River, which had already been altered by 

Holtwood Dam (built 1910) and the Conowingo Project (built 1928) when the Project was 

initially constructed in the 1960s. 

Effect of Entrainment and Impingement on Resident and Migratory Fish Populations 

Non-Project factors that may affect American shad populations in the watershed include upstream 

and downstream passage efficiency at the Conowingo, Holtwood, Safe Harbor, and York Haven 

Dams. In addition, predation, by-catch, and competition are possible factors impacting the 

American shad population. In the ocean, American shad are likely preyed upon by many species 

of fish, marine mammals, and seabirds. Inshore, it has been suggested that striped bass (Morone 

saxatilis) predation may limit the American shad population. Bycatch in commercial fisheries is 

a threat of significant concern for American shad populations. Significant bycatch primarily 

occurs in coastal ocean trawl fisheries for Atlantic herring (Clupea harengus), Atlantic mackerel 

(Scomber scombrus) and squid. Competition with other aquatic species for food resources could 

E-105



impact American shad abundances. For example, gizzard shad populations increased dramatically 

in the mid-20th century as broad based ecological changes provided a potential increase in 

suitable habitats. 

Since the institution of trap and transport and volitional upstream American shad passage at 

Conowingo Dam, entrainment of migratory American shad from Conowingo Pond has resulted 

from the pumping operations of the Project. Based on Exelon’s analysis, which indicated an 

entrainment rate ranging from 3.6% to 5.1%, this cumulative impact is moderate within the 

context of other past, present and future actions affecting American shad populations in the 

Lower Susquehanna River. 

Downstream passage of juvenile shad has been affected by pumping operation of the Muddy Run 

Project. This impact is moderate when considered in the context of other past, present, and 

future actions within the Lower Susquehanna River basin. Exelon’s analysis indicates that the 

estimated entrainment rate at the Project ranges from approximately 2.9% to 6.6% for 

downstream emigrating juvenile shad. 

Since the Project became operational in the 1960s, entrainment and mortality of resident fish 

populations within Conowingo Pond and Muddy Run Power Reservoir have occurred. However, 

both historic and current fish population data collected within Conowingo Pond and Muddy Run 

Power Reservoir indicate a healthy and robust fishery exists. In addition, data from historic and 

current creel surveys of Conowingo Pond show that a healthy year-round sport fishery is present. 

Exelon’s analysis of current and future impacts indicate that entrainment impacts related to 

Project operations are expected to be low to moderate during generation, and moderate during 

pumping. In addition, survival potential for entrained resident fish is expected to range from 80- 

100% depending on the particular life stage and species. 

Construction of Conowingo Dam in 1928 effectively closed the Susquehanna River to upstream 

migration of eels at river mile 10. Remnants of a stocking program in Pennsylvania that ended 

decades ago are occasionally taken. Elver stocking above Conowingo Dam was resumed in 2008 

by USFWS. 

Operational capacity will not be added and physical modification will not be made under the 

proposed alternative. The cumulative impacts of the action are evaluated within the context and 

the planned expansion program of the Holtwood Project under possible future scenarios. 

Increased American shad upstream passage efficiency and diminishment of migratory delays at 

E-106



the Holtwood Project will likely decrease the expected entrainment rates at the Muddy Run 

Project, as well as increase the near-field passage rate at the Muddy Run Project. Effects on 

alewife and blueback herring would likely be similar to American shad based on similar 

migratory behaviors. Providing upstream and downstream trap and transport program for 

American eel passage between Conowingo and York Haven Dams will likely minimize impacts 

from Muddy Run Project operations on American eel in the future. 

Effect of Power Reservoir Fluctuations on Aquatic Habitat 

Muddy Run generally follows the operating pattern where generation occurs during the day and 

pumping occurs at night. As a result, there can be large fluctuations in the Power Reservoir and 

of lesser magnitude in Conowingo Pond. The water level fluctuations can have direct effects on 

the plant and animal communities in these near-shore and littoral areas. At the Muddy Run 

Project, greater effects can be expected in the Power Reservoir as the water level changes are 

greater than in Conowingo Pond. Effects of Muddy Run operations on near-shore habitat in the 

Power Reservoir are expected to be moderate; since the reservoir does not support high quality 

habitat. 

Many of the same effects from water level fluctuations on near-shore habitat can be expected for 

riparian and littoral zones. The substantial fluctuation of the Power Reservoir periodically 

exposes the littoral zone and periodically floods the riparian zone. This can suspend sediments 

and either uproot aquatic and shoreline vegetation or expose the root systems of riparian plants 

leaving them susceptible to disease, freezing and even animals. Water level fluctuations tend to 

reduce littoral zone habitat and make the habitat that does persist unstable. This unstable littoral 

habitat is not suitable for many aquatic species; therefore it is not fully utilized. As fluctuations 

in Conowingo Pond tend to be lesser in magnitude, effects on the littoral zone are considered 

minor and effects on riparian habitat are considered negligible. 

Operational capacity will not be added and physical modification will not be made under the 

proposed action. The cumulative impacts of the action are evaluated within the context of the 

geographic scope for cumulative effects, which was defined by FERC in their Revised Scoping 

Document as the Susquehanna River from the Safe Harbor Project to Havre de Grace, Maryland, 

and the upper Chesapeake Bay. The Proposed alternative of the Project, in combination with 

other activities within the watershed, will not alter existing reservoir aquatic habitat conditions for 

the reasonably foreseeable future. 

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Entrainment, Impingement, and Mortality 

Exelon’s environmental analysis indicated that entrainment, impingement, and mortality resulting 

from Project operations have relatively minor impacts on resident and migratory fish species; 

therefore, Exelon is not proposing any environmental measures at this time. 

Effects of Thermal and Velocity Barriers to Migratory Fish Movement 

Exelon’s environmental analysis indicated that the effects of thermal and velocity barriers to 

migratory fish movements are negligible; therefore, Exelon is not proposing any environmental 

measures at this time. 

Effects on Invasive Zebra Mussels and Other Exotics 

Exelon’s environmental analysis indicated that the Project may indirectly facilitate the spread of 

the invasive zebra mussel and other exotic mollusks. Exelon proposes no environmental measures 

related to this issue at this time. 

3.3.3.5 Unavoidable Adverse Impacts 

No unavoidable impacts are expected to aquatic resources in the Muddy Run Project. 

E-108



TABLE 3.3.3.1-1: FISH SPECIES KNOWN TO OCCUR IN MUDDY RUN POWER 

RESERVOIR AND RECREATION LAKE 

Common Name Scientific Name 

E-109 

Muddy Run 

Reservoir 1 

Muddy Run 

Recreation 

Lake 

American eel Anguilla rostrata X 

Banded killifish Fundulus diaphanus X X 

Black crappie Pomoxis nigromaculatus X X 

Blacknose dace Rhinichthys atratulus X X 

Bluegill Lepomis macrochirus X X 

Bluntnose minnow Pimephales notatus X X 

Brook trout Salvelinus fontinalis X X 

Brown bullhead Ameiurus nebulosus X X 

Brown trout Salmo trutta X X 

Channel catfish Ictalurus punctatus X X 

Comely shiner Notropis amoenus X 

Common carp Cyprinus carpio X X 

Common shiner Luxilus cornutus X 

Creek chub Semotilus atromaculatus X X 

Creek chubsucker Erimyzon oblongus X 

Fallfish Semotilus corporalis X X 

Fathead minnow Pimephales promelas X X 

Gizzard shad Dorosoma cepedianum X X 

Golden shiner Notemigonus crysoleucas X X 

Green sunfish Lepomis cyanellus X X 

Hybrid striped bass Morone saxatilis x M. chrysops X 

Largemouth bass Micropterus salmoides X X 

Logperch Percina caprodes X 

Muskellunge Esox masquinongy X 

Northern hog sucker Hypentelium nigricans X X 

Northern pike Esox lucius X X 

Pumpkinseed Lepomis gibbosus X X 

Quillback Carpiodes cyprinus X X 

Rainbow trout Oncorhynchus mykiss X 

Redbreast sunfish Lepomis auritus X X 

River chub Nocomis micropogon X




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Muddy Run 

Reservoir 1 

Rock bass Ambloplites rupestris X 

Rosyface shiner Notropis rubellus X 

Muddy Run 

Recreation 

Lake 

Rosyside dace Clinostomus funduloides X X 

Satinfin shiner Cyprinella analostana X 

Shield darter Percina peltata X 

Shorthead redhorse Moxostoma macrolepidotum X X 

Smallmouth bass Micropterus dolomieu X X 

Spotfin shiner Cyprinella spilopterus X X 

Spottail shiner Notropis hudsonius X X 

Swallowtail shiner Notropis procne X 

Tessellated darter Etheostoma olmstedi X X 

Tiger muskellunge Esox lucius x E. masquinongy X 

Walleye Sander vitreus X X 

White catfish Ameiurus catus X 

White crappie Pomoxis annularis X X 

White sucker Catostomus commersonii X X 

Yellow bullhead Ameiurus natalis X X 

Yellow perch Perca flavescens X X 

Goldfish Carassius auratus X 

1 Egg, larva, and/or adult life stages identified. 

Sources: 

Susquehanna River Anadromous Fish Restoration Committee (2006), PPL and Kleinschmidt (2006), Normandeau 

Associates (2001), Normandeau Associates (2000), Robbins et al. (1974), RMCa (1979).



TABLE 3.3.1.1-2: FISH SPECIES COMPOSITION IN CONOWINGO POND, 2010-11 

Species Percent of Catch 

Gizzard shad 42.4% 

Channel catfish 19.5% 

Spotfin shiner 7.9% 

Comely shiner 6.8% 

Bluegill 6.6% 

Green sunfish 4.0% 

Spottail shiner 3.0% 

Bluntnose minnow 1.8% 

Smallmouth bass 1.4% 

Rock bass 1.3% 

Other species 5.3% 

TABLE 3.3.1.1-3: COMPARISON OF CREEL SURVEYS AT MUDDY RUN 

RECREATION LAKE. 

Year 1985 1987 2010 

Months surveyed April - October June - October April - November 

Estimated effort (h) 92,294 17,801 51,940 

Number of trips 19,227 4,140 17,632 

Average trip length (h) 4.8 4.3 Boat 3.6 

Shore 2.5 

Directed catch rate Boat 0.46 Boat 0.67 Boat 0.58 

Shore 0.38 Shore 0.60 Shore 0.50 

Harvest rate Boat 0.12 Boat 0.05 Boat 0.11 

Shore 0.15 Shore 0.07 Shore 0.21 

Angler's residence (%) Lancaster (65) Lancaster (54) Lancaster (67) 

Dominant species sought Anything Anything Anything 

Estimated harvest 14,275 1,614 4,954 

Retention rate 12% 32% 

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TABLE 3.3.3.1-4: ESTIMATED CATCH AND HARVEST TOTALS ON CONOWINGO 

POND IN 2010 

Species 

Spring 

Catch Harvest 

Summer 

Catch Harvest 

Fall 

Catch Harvest 

TOTAL 

Catch Harvest 

Gizzard shad 12 0 — — — — 12 0 

Common carp 241 205 1428 166 264 0 1933 371 

Catfish 836 0 361 0 — — 1197 0 

Channel catfish 1719 367 7239 1208 849 52 9807 1627 

Flathead catfish 690 395 180 39 553 87 1424 520 

Smallmouth bass 5082 0 4606 0 1759 35 11447 35 

Largemouth bass 3197 0 3077 0 744 44 7019 44 

Sunfish 404 0 605 0 277 0 1286 0 

Bluegill 1787 0 6112 0 186 0 8085 0 

Rock bass 587 0 848 0 43 0 1478 0 

Green sunfish — — 13 0 — — 13 0 

Pumpkinseed — — 26 0 — — 26 0 

White crappie — — 13 0 — — 13 0 

Black crappie 54 0 — — — — 54 0 

Striped bass 66 0 — — 27 27 93 27 

White perch — — 90 0 — — 90 0 

Walleye 242 35 142 0 150 17 533 52 

Striped bass hybrid — — — — 18 0 18 0 

TOTAL 14,917 1,001 24,740 1,413 4,869 262 44,526 2,676 

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TABLE 3.3.3.1-5: BENTHIC MACROINVERTEBRATES IDENTIFIED IN 

CONOWINGO POND AND MUDDY RUN RESERVOIR 

Higher Taxon Genus or Species Common Name 

Mollusks 

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Below Holtwood 

Dam1 

Physidae Physella Snail X 

Spaeriidae 

Sphaerium Peaclam X 

Elliptio complanata Eastern elliptio X 

Lampsilis cariosa Yellow lampmussel X 

Muddy 

Run 

Reservoir2 

Lymnaeidae Stagnicola sp. Pondsnail X 

Amphipods 

Crangonyctidae Crangonyx Amphipod X 

Gammaridae 

Gammarus Amphipod X 

Gammarus fasciatus Amphipod X 

Hyallelidae Hyalella Amphipod X 

Mayflies 

Baetidae 

Baetidae 

Caenidae Caenis 

Acentrella Small mayfly X 

Baetis Small mayfly X 

Centroptilum Small mayfly X 

Heterocloeon Small mayfly X 

Small square-gill 

mayfly 

Ephemeridae Hexagenia limbata Mayfly X 

Heptageniidae 

Stenacron Mayfly X 

Stenonema Mayfly X 

Potamanthidae Anthopotamus Hacklegill mayfly X 

Tricorythidae Tricorythodes 

Damselflies/Dragonflies 

Coenagrionidae Argia 

Little stout crawler 

mayfly 

Narrow-winged 

damselfly 

Corduliidae Neurocordulia Emerald dragonfly X 

Libellulidae Leucorrhinia Common skimmer X 

Libellulidae 

Dobsonflies 

Libellula Common skimmer X 

Agnetina Common stonefly X 

X 

X 

X




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Dam1 

Corydalidae Corydalus Dobsonfly X 

Sialidae Sialis Dobsonfly X 

Caddisflies 

Hydropsychidae 

Cheumatopsyche Netspinning caddisfly X 

Hydropsyche Netspinning caddisfly X 

Macrostemum Netspinning caddisfly X 

Muddy 

Run 

Reservoir2 

Leptoceridae Oecetis Longhorned caddisfly X X 

Philopotamidae Chimarra Finger-net caddisfly X 

Beetles 

Flies 

Elmidae Dubiraphia Riffle beetle X 

Elmidae Optioservus Riffle beetle X 

Elmidae 

Stenelmis Riffle beetle X 

Psephenus Water-penny beetle X 

Ceratopogonidae Biting midge X 

Chaoboridae 

Chaoborus Phantom midge X 

Chaoborus 

pumnctipennis 

Phantom midge 

Chironomidae Midge X X 

Chironomidae 

Chironomidae 

Anatopynia sp. Midge X 

Chironomus decorus Midge X 

Coelotanypus concinnus Midge X 

Cryptochironomus 

fulvus 

Midge 

Polypedilum halterale Midge X 

Procladius sp. Midge X 

Tanytarsus Midge X 

Dolichopodidae Long-legged fly X 

Oligochaete Worms 

Oligochaeta Earthworm X 

Tubificidae 

Branchiura sowerbyi X 

Limnodrilus 

hoffmeisteri 

Ilyodrilus templetoni X 

X 

X 

X




Others 

E-115 



Dam1 

Cambaridae Orconectes Crayfish X 

Gerridae 

Gerris Water strider X 

Trepobates Water strider X 

Muddy 

Run 

Reservoir2 

Hydracarina Aquatic mite X 

Isopoda Caecidotea Isopod X 

Lepidoptera Petrophila Snout-moth X 

Lophopodidae Pectinatella magnifica Freshwater bryozoan X 

Nematoda Nematode worm X 

Plagiostomidae Hydrolimax grisea Planarian X 

1 Source: Normandeau Associates (2000) 

2 Source: RMC (1979)



TABLE 3.3.3.1-6: ALGAL SPECIES IDENTIFIED IN CONOWINGO POND AND 

MUDDY RUN RESERVOIR 

Taxon 

Euglenoids 


Pond 

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Muddy Run 

Reservoir 

Euglena X X 

Trachelomonas X X 

Green Algae 

Chlamydomonas X 

Eudorina X X 

Pandorina* X X 

Pleodorina* X X 

Volvox X X 

Haematococcus X 

Sphaerocystis X X 

Dispora X 

Golenkinia X 

Micractinium X X 

Errerella X 

Dictyosphaerium X X 

Coelastrum X 

Hydrodictyon X 

Pediastrum* X X 

Oocystis X X 

Ankistrodesmus X 

Closteriopsis X 

Kirchneriella X 

Selenastrum X 

Actinastrum X X 

Scenedesmus X X 

Closterium X X 

Cosmarium X X 

Staurastrum X X 

Zygnema X 

Protococcus X



Taxon 


Pond 

Spirogyra X 

Yellow-Green Algae 

Gloeobotrys X 

Yellow-Brown Algae 

E-117 

Muddy Run 

Reservoir 

Mallomonas X X 

Synura X X 

Dinobyron X X 

Diatoms 

Melosira* X X 

Stephanodiscus X X 

Asterionella X X 

Fragilaria X X 

Gyrosigma X 

Navicula X 

Nitzschia X X 

Brown Algae 

Ceratium X X 

Peridinium X X 

Blue-Green Algae 

Coccochloris X X 

Gomphosphaeria* X X 

Anabaena* X X 

Aphanizomenon X X 

Nostoc X 

Anacystis* X X 

Rivularia X 

Oscillatoria X X 

Spirulina X 

*Most common genera observed in Conowingo Pond and Muddy Run Reservoir. 

(Source: RMC 1979)



TABLE 3.3.3.1-7: ZOOPLANKTON SPECIES IDENTIFIED IN MUDDY RUN 

RESERVOIR 

Cladocera Copepoda 

Leptodora kindtii Cyclopoid copepodids 

Diaphanosoma 

leuchtenbergianum 

Cyclops vernalis 

Daphnia parvula C. bicuspidatus thomasi 

D. retrocurva C. scutifer 

D. galeata mendotae Mesocyclops edax 

D. catawba Eucyclops agilis 

D. ambigua E. speratus 

Moina affinis Tropocyclops prasinus 

Ceriodaphnia lacustris Macrocyclops albidus 

C. quadrangula 

Paracyclops fimbriatus 

poppei 

C. reticulata Calanoid copepodids 

Scapholeberis aurita Diaptomus pallidus 

Bosmina longirostris D. siciloides 

Eubosmina coregoni Harpacticoida 

Ilyocryptus spinifer nauplii 

I. sordidus 

Macrothrix laticornis 

M. rosea 

Pleuroxus hamulatus 

P. denticulatus 

P. striatus 

Alona affinis 

A. quadrangularis 

A. costata 

A. guttata 

A. rectangula 

Leydigia leydigi 

Chydorus sphaericus 

Pseudochydorus globosus 

Camptocercus rectirostris 

Eurycercus lamellatus 

(Source: RMC 1979) 

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3.3.4. Terrestrial Resources 


Based on stakeholder feedback and FERC’s SD2, existing, relevant, and reasonably available 

information from Exelon’s PAD and additional available literature was sufficient to determine the 

potential effects of the Project on the large majority of terrestrial resources known to exist within 

the Project boundary. Two resource specific studies were performed for relicensing of the 

Muddy Run Project to identify potential effects on terrestrial species. These studies included the 

Transmission Line Avian Interaction Study and the Osprey Nesting Survey. In addition, qualified 

personnel performed field studies to document existing terrestrial resources within the Project 

boundary. For Exhibit E, Exelon is presenting the most relevant literature available to 

characterize this resource, the observations of field studies performed in 2010 and 2011, and 

studies performed for assessing avian interactions with the existing transmission line and the 

identification of osprey nesting locations. 

3.3.4.1.1 Upland Botanical Resources 

The region encompassing the Project area is characterized by a diversity of terrestrial botanical 

resources, which are influenced by soil type, hydrology, climate, and historic and current land 

use. General plant communities in the Project area include old fields, woodlands, and cultivated 

fields. 

Studies have been conducted to assess areas adjacent to the Muddy Run Project area and 

regionally. These studies include those conducted as part of the Holtwood Redevelopment Project 

(PPL and Kleinschmidt 2006, Keever 1972, and Cohen 2004). They provide data to generally 

describe the predominant terrestrial botanical communities that may lie within and in the vicinity 

of the Muddy Run Project. Additional field surveys were not conducted to determine the presence 

and/or extent of these botanical resources or the respective plant community boundaries within 

the Project boundary. 

Pennsyvlania GAP Anlaysis Program (GAP) GIS-based land cover datasets with dominant plant 

species descriptions (Myers and Bishop 1999) were reviewed, in conjunction with soils data, 

landscape setting, and aerial photographs, to estimate the acreage of plant communities likely to 

be present wthin the Project boundary. The botanical resources were categorized in accordance 

with the classification system developed by the PADCNR (Fike 1999). This system was 

E-119



developed for describing terrestrial communities throughout Pennsylvania. Within this context, 

the primary natural plant communities are likely to include: 

� Mixed mesophytic and rich hemlock-mesic hardwood forest (1,260 acreas); 

� Dry oak-mixed hardwood or red oak-mixed hardwood forest (265 acres); and 

� Virginia pine-mixed hardwood forest (38 acres). 

A small portion of the Project area in the transmission line corridor is underlain with serpentinite 

bedrock (see unit Xu in Figure 3.3.1.1-1). However, this area is currently in agricultural use and 

does not support a Serpentine Virginia pine-oak forest. It is estimated that agricultural cropland 

comprises 148 acres within the Project boundary and maintained lawns comprise 257 acres. 

The three upland forest communities identified above are described below. 

Mixed Mesophytic and Rich Hemlock-Mesic Hardwood Forest 

These communities are associated with the deep ravines and gorges that occur along the tributary 

streams leading into the Susquehanna River. Muddy Creek (crossed by the Muddy Run Project 

transmission line corridor) and the Ferncliff Wildlife and Wildflower Preserve are examples of 

locations where these communities dominate (Keever 1972). A few of these areas may support 

virgin stands of timber along the steep slopes. Species dominance within these communities is 

variable between locations, and assemblages differ slightly from those listed in Fike (1999). 

In the Ferncliff area, dominant species (in descending order) include American beech (Fagus 

grandifolia), eastern hemlock (Tsuga canadensis), tuliptree (Liriodendron tulipifera), white ash 

(Fraxinus americana), northern red oak (Quercus rubra), scarlet oak (Q. coccinea), sugar maple 

(Acer saccharum), chestnut oak (Q. montana), and American basswood (Tiliea americana) 

(Keever 1972). Additional species that may occur at other locations include cucumber-tree 

(Magnolia acuminata), black cherry (Prunus serotina), black walnut (Juglans nigra), shagbark 

hickory (Carya ovata), Ohio buckeye (Aesculus glabra), and yellow buckeye (A. flava). The 

understory of this community may include pawpaw (Asimina triloba), bladdernut (Staphylea 

trifolia), rosebay (Rhododendron maximum), eastern redbud (Cercis canadensis), and witch-hazel 

(Hamamelis virginiana). 

E-120



Dry Oak-Mixed Hardwood and Red Oak-Mixed Hardwood Forest 

These assemblages primarily consist of hardwoods occurring on mesic (red oak-mixed) and drier 

(dry oak-mixed) conditions. Red oak-mixed hardwood forests make up much of Pennsylvania’s 

hardwood forests (Fike 1999). 

This community is found throughout the region at elevations somewhat greater than the mixed 

mesophytic forests. Species typically found within this community include northern red oak, red 

maple (Acer rubrum), black oak (Quercus velutina), white oak (Q. alba), yellow birch (Betula 

alleghaniensis), and mockernut hickory (C. tomentosa). Understory shrubs include northern 

arrowwood (V. recognitum), maple-leaved viburnum (Viburnum acerifolium), spicebush (Lindera 

benzoin), and H. virginiana. The herbaceous layer is variable and may include wild-oats 

(Uvularia sessilifolia), may-apple (Podophyllum peltatum), and striped wintergreen (Chimaphila 

maculata). 

Virginia Pine-Mixed Hardwood Forest 

This community is found in dry, rocky, higher elevation areas and is dominated by three species, 

including chestnut oak, Virginia pine (Pinus virginiana), and table mountain pine (P. pungens) 

(USDOI 1980). Other species that may be associated with this community include red oak, scarlet 

oak, black oak, and white oak, along with black cherry, red maple, sweet birch (Betula lenta), and 

hickories (Carya spp.). The understory is a mix of northern red cedar (Juniperus virginiana), 

shining sumac (Rhus copallina), and Allegheny blackberry (Rubus allegheniensis) (Fike 1999). 

Other communities are likely associated with wetland and riparian areas and may include red 

maple-black gum palustrine forest, sycamore-river birch-box elder floodplain forest, and red 

maple-elm-willow floodplain swamp. Wetland vegetation is described in Section 3.3.4.1.4. 

3.3.4.1.2 2010 and 2011 Field Surveys 

Field surveys conducted in 2010 and 2011 to identify habitat types within and around the Muddy 

Run Project area had findings generally consistent with the regional plant community types 

expected and described above. The Muddy Run Power Reservoir is surrounded by a variety of 

land use cover types, the majority of which are upland forest communities. Within the 

established parkland surrounding the adjacent recreation lake, there are maintained lawns as well 

as scattered woodland. Agricultural cropland is also present, particularly in the eastern portions 

of the study area, as well as within a portion established as a game reserve on the western shore. 

E-121



Forested areas include mature woodland as well as more scrubby immature growth. Dominant 

tree species included green ash (Fraxinus pennsylvanica), sycamore (Platanus occidentalis), 

black willow (Salix nigra) and box elder (Acer negundo) along the reservoir shorelines; red oak 

(Quercus rubra), white oak (Quercus alba), pignut hickory (Carya glabra), sweet birch (Betula 

lenta), black cherry (Prunus serotina), tulip poplar (Liriodendron tulipifera) and sugar maple 

(Acer saccharum) in forest interiors, with black locust (Robinia pseudoacacia) and black walnut 

(Juglans nigra) along forest edges. Invasive exotic species, including mile-a-minute (Persicaria 

perfoliata), tree-of-heaven (Ailanthus altissima), autumn olive (Elaeagnus umbellata), bush 

honeysuckle (Lonicera maackii) and Japanese stiltgrass (Microstegium vimineum) were prevalent 

in areas along the western shore of the reservoir, but less so along the eastern shore. Such 

invasive plants were most common along edge areas near the recreation park and in transmission 

line ROWs. Evergreen communities were also found in the western portion of the study, 

including eastern red cedar (Juniperus virginiana), Virginia pine (Pinus virginiana), white pine 

(P. strobus), and short-leaf pine (P. echinata) 

3.3.4.1.3 Terrestrial Wildlife 

The physiographic setting of the Project area, its relatively large tracts of undisturbed terrestrial 

habitats and the broad-leaved terrestrial and palustrine forests described above provide a wide 

variety of habitats for terrestrial wildlife. These include over-wintering and breeding habitats for 

both migratory and resident bird species. Wildlife surveys have been performed for other studies 

adjacent to and including parts of the Project area (Cohen 2004; PPL and Kleinschmidt 2006). 

Terrestrial wildlife identified in these surveys is likely to be similar to wildlife within the Muddy 

Run Project. 

Non-target bird and herpetofaunal species observed during field surveys conducted in 2010 and 

2011 as part of relicensing studies are listed in Tables 3.3.4.1.3-1 and 3.3.4.1.3-2. 

3.3.4.1.4 Wetlands, Riparian, and Littoral Habitat 

The Project area encompasses a variety of water-dependent habitats that can be variously defined 

by frequency of inundation, water depth, and geomorphic position in the landscape adjacent to an 

open body of water. These habitats are characterized by a variety of vegetation types and wildlife 

species. Wetlands, the riparian zone, and the littoral zone are three broad habitat types that are 

present in the Project area. 

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Initial field surveys discussed in the PAD were limited to the Muddy Run Reservoir shoreline and 

the Susquehanna River crossed by the primary transmission lines and occupied by the Muddy 

Run powerhouse. Additional surveys conducted in 2010 included all Project lands around the 

Muddy Run Reservoir and the entire associated transmission line. The findings of these studies 

are summarized below. 

Wetland Habitat and Vegetation 

Muddy Run Reservoir 

National Wetland Inventory (NWI) maps were reviewed to identify the potential location of 

wetlands within the boundary of the Muddy Run Project (Figure 3.3.4.1.4-1). NWI maps identify 

wetlands in accordance with the Cowardin classification which includes littoral and some open 

water habitats as wetlands. NWI wetlands within the Project boundary that are not littoral or open 

water habitats are limited to: 1) temporarily flooded deciduous broad-leaved forested and scrub- 

shrub wetlands and narrow-leaved persistent emergent wetlands at the uppermost impounded 

reach of Muddy Run in the Recreation Lake and 2) a temporarily flooded narrow-leaved 

persistent emergent wetland at the uppermost impounded reach of an unnamed tributary to the 

Muddy Run Reservoir south of Muddy Run. 

Three wetlands were identified on land adjacent to Muddy Run Reservoir during field surveys in 

2010, and two wetlands were identified on other Project lands during field surveys in 2011. 

These wetlands are described below. 

Wetland 2 is located in the northeast corner of the Power Reservoir and is identified as a 

palustrine emergent (PEM) on the NWI map. This wetland originates as a spring seep that drains 

into the reservoir. Dominant plants include sedges (Carex spp.) and jewelweed (Impatiens 

capensis). Soils were muddy but not mucky and were underlain by gravel and rock 

approximately 1-2 inches below the surface. 

Wetland 3 is a palustrine forested (PFO) wetland located along a small stream which drains into 

the northeast corner of the reservoir. It is dominated by skunk cabbage (Symplocarpus foetidus), 

red maple (Acer rubrum), and spicebush (Lindera benzoin). 

Wetland 4 consists of a PFO wetland with PEM components, and is associated with a stream that 

ultimately flows into the reservoir. Dominant vegetation included sycamore (Platanus 

occidentalis) and skunk cabbage. 

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Wetland 5 is a PEM/ palustrine scrub-shrub (PSS) wetland located adjacent to the upper reaches 

of the recreation lake. Dominant vegetation included sedges, rushes, cattail (Typha latifolia), rice 

cutgrass (Leersia oryzoides), sweetflag (Acorus calumus) and blue vervain (Verbana hastata). 

A non-Project related natural gas transmission line, operated by Williams Gas Pipeline 

Corporation (Williams), traverses the southeastern boundary of the Project area. One wetland 

(Wetland 6) was identified within the confines of the pipeline right-of-way (ROW). This wetland 

was a PEM, with dominant vegetation including common reed (Phragmites australis), cattail, 

sedges, rushes, jewelweed, reed canary grass (Phalaris arundinacea) goldenrod (Solidago spp) 

and aster (Aster spp). Over half of the wetland was dominated by Phragmites, and had 

compacted soils related to the presence of the pipeline. Two seep areas were present that 

supported the more diverse vegetation and had mucky spots. These seeps drained off-site into 

Wissler’s Run, which in turn drains into the Susquehanna River. 

Transmission Line Corridor and Muddy Run Powerhouse 

The Muddy Run Powerhouse is constructed at the base of the steep rocky shoreline of the 

Susquehanna River between the Norfolk Southern rail and the water’s edge. The primary 

transmission line corridor spans the Susquehanna River from the roof of the powerhouse to the 

other side just below the PFBC boat launch upstream of Muddy Creek. Wires are attached to 

towers located on Turkey Island (one tower), a small unnamed island immediately downstream 

(one tower), and Lower Bear Island (six towers). 

Overhead transmission lines extend over the Susquehanna River to Turkey Island, turn south to 

Lower Bear Island, and continue to the York County mainland. The transmission line ROW 

continues up a steep bluff and jogs south over the Muddy Creek and tributaries situated in 

ravines. Deciduous woods surround the transmission line to a point approximately 500 feet south 

of Muddy Creek, at which point the ROW traverses agricultural fields (both pasture and 

cropland) to the terminus of the study area near Lay Road over two miles to the southeast. 

Wooded riparian zones were present along 4 stream crossings (Muddy Run Creek and unnamed 

tributaries to Muddy Run Creek). 

One wetland, described as Wetland 1, was identified within the transmission line corridor, and is 

located within the confines of a pig pasture. This PEM wetland was dominated by sedges (Carex 

spp.), rushes (Juncus spp.), and jewelweed (Impatiens capensis) and exhibited evidence of 

groundwater seepage. The Lancaster County Natural Areas Inventory (Nature Conservancy 

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1990, 1993) indicates that the western margin of Lower Bear Island, between two cleared power 

rights-of-way, consists of a hardwood dominated wetland. Reconnaissance level field 

observations recorded at the northernmost edge of this area along the shore identify river birch 

and purple loosestrife. This supports the presence of jurisdictional wetlands here. Other woody 

vegetation are likely to be similar to the forested wetlands described by PPL and Kleinschmidt 

(2006) along the Holtwood Dam tailrace on the east margin and downstream tip of Piney Island 

and in the Holtwood Dam spillway along the western margin of the river. 

3.3.4.1.5 Littoral Zone Habitat and Vegetation 

The littoral zone is the nearshore area extending from the seasonal high water level to the furthest 

extent of rooted aquatic vegetation (Wetzel 1975). The depth of this extent is usually defined as 

where about 1 percent of surface light penetrates (Environmental Protection Agency undated). 

The magnitude and frequency of rapid water fluctuations in the Power Reservoir precludes the 

establishment of emergent or submergent rooted vegetation. Field surveys found that the 

reservoir margin is free of vegetation. 

A field-based quantification of the full extent of the littoral zone was not conducted. Aerial 

photographs depicting the exposed littoral zone at low water levels (see Figure 3.3.1.1.8-1) were 

used to approximate that littoral zone area along the upper reservoir shoreline is on the order of 

240 acres. 

Steep bathymetric slopes at island margins beneath the transmission line crossing of the 

Conowingo Pond do not display a littoral zone. Nearshore slopes near the emergent wetland at the 

PFBC boat launch are gentler with emergent aquatic water willow present. The littoral zone 

beneath the transmission line within the Project boundary is 0.2 acres. 

3.3.4.1.6 Riparian Zone Habitat and Vegetation 

Riparian zones border waterways landward of the littoral zone. In Fischer et. al. (2001), the 

United States Army Corps of Engineers (USACE) defines riparian zones as long strips of 

vegetation adjacent to inland aquatic systems that affect or are affected by the presence of water. 

Riparian habitat can be a wetland or non-wetland (upland) (Tiner 1999). 

The extent of riparian habitat surrounding the reservoir is best characterized by the percentage 

metric rather than by acreage. To provide acres of riparian habitat it would be necessary to 

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arbitrarily choose a buffer width (e.g., 50-feet, 150-feet, etc). 2010 satellite imagery indicates 

that 84 percent of the reservoir shoreline is bordered by riparian habitat (woody vegetation). 

Wetland, Littoral, and Riparian Wildlife 

Littoral zones provide habitat for fish and benthic invertebrates. These aquatic resources are 

described in Section 3.3.3. Wetlands and the riparian zone of the Project area provide habitats for 

many forms of wildlife. There is no documentation of mammals specifically utilizing wetlands 

and riparian zones in the Muddy Run Project area, but numerous reptile and amphibian species 

were found during surveys conducted for relicensing surveys (Table 3.3.4.1.3-2). Also, several of 

the bird species identified in Tables 3.3.4.1.3-1 utilize wetland and riparian areas, including bald 

eagle and osprey, which were found to nest in the Project area. 

3.3.4.1.7 Sensitive Botanical Resources 

Natural areas with unique habitats known to support, or potentially support, listed and non-listed 

species or communities of concern are partly within the Muddy Run Project boundary. These 

include: 

• Erosional Remnants (recognized by PADCNR) 

• Riverside Outcrop Plant Community (recognized by PADCNR) 

Erosional Remnants 

Erosional Remnants are a heritage geology type identified by the PADCNR (PADCNR 2008). 

These are landforms or outcrops produced by erosion (e.g., free-standing rock columns or 

boulders; bedrock pinnacles, peaks or cliffs; or non-glacial potholes). The bedrock islands crossed 

by the Muddy Run Project transmission corridor are examples of erosional remnants. 

Riverside Outcrop Plant Community 

The Riverside Outcrop Community is recognized by the Pennsylvania Natural Heritage Program 

as an imperiled to critically imperiled plant association. It is found along banks of major rivers 

with rock outcrops subject to winter ice scour, periodic flooding, and periods of drought. This 

community, often associated with erosional remnants, is present in the Conowingo Islands reach 

of the Susquehanna River, which is occupied by the Muddy Run Project powerhouse and is 

crossed by the primary transmission line corridor. Transmission line towers are located on Turkey 

Island, Lower Bear Island, and an unnamed erosional remnant island. 

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The rocky outcrop river shoreline of the Conowingo Islands reach along Lower Chanceford 

Township is part of the Conowingo Island Macrosite, identified in the York County Natural 

Areas Inventory as a Priority Preservation Site for maintaining biological diversity in York 

County (Nature Conservancy 2004). The York County NAI reports 12 occurrences of species of 

special concern as well as other uncommon species. This area supports a diverse plant community 

with habitats that range from floodplain thickets and forests, to outcrop cliffs, vernal ponds, dry 

shrub heath, mesophytic and dry rocky forests, and littoral zone. Plants on rocks typically grow in 

crevices and hollows where sediment accumulates. The Lancaster County Natural Heritage 

Inventory 2008 update to the Lancaster County NAI (PNHP 2008) includes the Conowingo 

Islands and adjacent riverside areas of the Lower Susquehanna River (Riverside Cliff/Outcrop 

Community) as a Natural Heritage Area providing habitat to 16 plant species of concern and three 

animal species of concern. 

3.3.4.1.8 Transmission Line Avian Interactions 

The lands and waters crossed by Project transmission lines and structures in the Project area 

support a diverse community of avian species. Transmission line avian interaction surveys were 

conducted between April 2010 and October 2010 in the Project transmission line right-of-way 

(ROW), which includes lines 220-06 and 220-07 and extends 4.25 miles south from the Muddy 

Run powerhouse to PBAPS Substation North (URS and GSE 2012d). Methods used to examine 

potential risk included data collection consisting of avian species interactions in the ROW (e.g., 

perching, flying, and nesting), habitat characterization, carcass searches, and facility information 

(towers and lines appurtenant to the Project). Approximately 86 hours of avian interaction 

observations, including two carcass searches, were conducted in the ROW. During the study 

1,367 avian interactions and one carcass were observed. Habitat was assessed and categorized for 

the purposes of the study according to type (e.g., forest, agricultural field, open water). Data 

collected were used to determine potential risk of electrocution and collision based on the data 

collected as related to environmental, biological, and engineering factors associated with risk to 

avian species especially raptors. 

Large raptors, including bald eagles, ospreys, and vultures concentrate in the area (Water 

Crossing) where transmission lines cross over Conowingo Pond from the Muddy Run 

Powerhouse to a slope above Muddy Creek Boat Launch. The remaining portion of transmission 

line ROW extends overland (Overland Crossing) through agricultural fields edged by forest. The 

basis for the potential for effects of Project transmission lines on birds, particularly raptors, at the 

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Water Crossing is based on the abundance of birds, especially large raptors, in the vicinity of the 

Water Crossing; the perpendicular placement of transmission lines across flight paths (e.g., 

waterways serve as flight paths) in open and shoreline habitat, and the presence of small diameter 

shield wires (low visibility to birds) situated above conducting wires. Therefore, the abundance 

of large species, the configuration of lines perpendicular to shorelines in an open/shoreline 

environment, and the presence of shield wires have potential for collision risk to raptors and other 

species concentrated in the vicinity of the Water Crossing. These factors apply to the potential 

for collision at the Water Crossing but differ with respect to potential for electrocution. 

The study concluded that the potential for electrocution in the entire area of study to be low. As 

stated in the study, although large raptors are abundant in the area of the Water Crossing, 

potential for electrocution is low there and in other portions of the transmission line ROW due to 

the inherent design of Project towers which are high-voltage towers with large (20 – 40 feet) 

separations between energized and grounded components. The separations between components 

on Project towers are more than adequate to accommodate the wrist-to-wrist distances and 

vertical heights of the specific large species present in the Project area. Therefore, there is low 

potential for raptors and/or other species to be electrocuted by bridging the space between 

components. 

The study also concluded, based on the lack of carcasses and/or observations of actual bird 

strikes, that deadly interactions of any avian species with towers or transmission lines appurtenant 

to the Project was not a common occurrence. As the results of the 2010 study indicated, harmful 

or deadly interaction is uncommon in the area of study although there is potential risk of collision 

in the area of the Water Crossing. Project lines and towers are considered to have minimal effects 

on avian species, including large avian species, due to the low potential for electrocution and low 

mortality in the area. 

Nesting in the ROW was only observed in successional forest on steep slopes where 

approximately seven small cup nests were observed high in the canopy (Observation Point No. 3). 

The nests were likely songbird nests and represent seasonal use of the area. Nesting by large 

birds in Project towers was not observed in the 2010 study. However, one nesting attempt in the 

Project area by osprey was observed in a tower on Turkey Island in 2011 during the 2011 Osprey 

Nesting Survey. The nest was a late season attempt in an area and was not actively used 

thereafter. 

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3.3.4.1.9 Transmission Line Vegetation Management 

PECO, an Exelon Company, is responsible for the vegetation management within the 

transmission line corridor from the Muddy Run powerhouse to the substation serving PBAPS. 

PECO utilizes American National Standards Institute (ANSI) A300 standards, which apply to 

professionals who provide for, or supervise the management of, trees, shrubs, and other woody 

landscape plants. ANSI A300 standards provide a framework for developing specifications to 

implement an integrated approach to management of vegetation. 

Integrated Vegetation Management (IVM), an element of ANSI A300, promotes sustainable plant 

communities that are compatible with the intended use of the site. For PECO transmission lines 

the IVM program is designed to provide reliable electric service to Exelon’s customers through 

reducing the conflict between tall trees and the electric transmission lines. IVM is also 

considered a Best Management Practice among electric utilities and is codified under ANSI A300 

Part 7: Tree Shrub, and Other Woody Plant Maintenance – Standard Practices (Integrated 

Vegetative Management a. Electric Utility Rights-of-Way). 

IVM does not outline specific timeframes for management activities; instead it outlines a 

comprehensive program for managing plant communities in which compatible and incompatible 

vegetation is identified, action thresholds are considered, control methods are evaluated, and 

selected control(s) are implemented to achieve a specific objective. Choice of control methods is 

based on effectiveness, environmental impact, site characteristics, safety, security and economics. 

IVM also incorporates specific environmental protection measures such as not impacting any 

species of concern; protecting wetlands and streams; and protecting cultural resource sites. 

PECO’s IVM program includes the designation of a wire zone and a border zone within the right- 

of-way. The wire zone is the section of right-of way directly under the transmission wires and 

extending outward 10 feet on each side of the wires. The wire zone is managed to promote a 

low-growing plant community dominated by grasses, herbs, and small shrubs less than three feet 

in height. The border zone is the remainder of the right of way, and is managed to promote 

shrubs and small trees lower than 25 feet at maturity. PECO’s IVM program incorporates a 

variety of manual, mechanical, and herbicide control techniques to limit the growth of tall 

growing woody species and encourage the development of appropriate vegetation within the 

separate zones in the right of way. 

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Exelon is not proposing any changes to the existing Project operations. The only changes to 

Project facilities include proposed maintenance and upgrades to the existing recreational 

facilities. The lower Susquehanna River in the vicinity of the Muddy Run Project contains two 

natural communities of concern. Continued operation of the Muddy Run Project is not expected 

to affect these communities. 

As indicated in Section 3.3.4.1.9, Exelon’s study of avian interactions with the existing 

transmission line documents the presence of several species of large birds in the water crossing 

area of the Muddy Run transmission line ROW. The study also concludes that although potential 

exists for collision with shield wires located on towers located in the water crossing, deadly 

interactions with transmission lines have not been a common occurrence. As the results of the 

2010 study indicated, harmful or deadly interaction is rare and considered to have minimal effects 

on larger avian species. 


Exelon is not proposing any environmental measures to address natural botanical communities or 

avian interactions with transmission lines. Studies and field surveys completed by Exelon have 

documented that environmental measures specifically related to wildlife resources are not 

warranted. 


Water level fluctuations and increased velocities from the Project may have unavoidable adverse 

impacts on natural shoreline plant communities, connected wetlands and the littoral zone. The 

fluctuations periodically inundate and drain any Power Reservoir shoreline wetlands or areas that 

have hydrologic connectivity to the Power Reservoir. 

Also, there may be some unavoidable adverse impacts in the form of large avian species’ 

interaction with transmission lines. The studies in 2010 indicated that these interactions are 

minimal. 

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TABLE 3.3.4.1.3-1: AVIAN SPECIES SEEN OR HEARD DURING SURVEYS (2010 – 

2011) 


American Crow Corvus brachyrhynchos 

American goldfinch Carduelis tristis 

American kestrel Falco sparverius 

American robin Turdis migratorius 

Bald eagle Haliaeetus leucocephalus 

Baltimore oriole Icterus galbula 

Barn swallow Hirundo rustica 

Belted kingfisher Megaceryle alcyon 

Black vulture Coragyps atratus 

Black-capped chickadee Poecile atricapillus 

Blue jay Cyanocitta cristata 

Blue-gray gnatcatcher Polioptila caerulea 

Bobolink Dolichonyx oryzivorus 

Brown thrasher Toxostoma rufum 

Canada goose Branta canadensis 

Carolina wren Thryothorus ludovicianus 

Caspian tern Sterna caspia 

Cedar waxwing Bombycilla cedrorum 

Common grackle Quiscalus quiscula 

Coopers hawk Accipiter cocperii 

Dark-eyed junco Junco hyemalis 

Double crested cormorant Phalacrocoraz auritus 

Downy woodpecker Picoides pubescens 

Eastern bluebird Sialia sialis 

Eastern kingbird Tyrannus tyrannus 

Eastern phoebe Sayomis phoebe 

Eastern pewee Pipilo erythrophthalmus 

Eastern wood pewee Contopus virens 

European starling Sturnus vulgaris 

Gray catbird Dumetella carolinensis 

Great blue heron Ardea alba 

Great crested flycatcher Myiarchus crinitus 

Great egret Ardea alba 

Great horned owl Bubo virginianus 

Green heron Butorides virescens 

Herring Gull Larus argentatus 

House finch Carpodacus mexicanus 

House sparrow Passer domesticus 

House wren Troglodytes aedon 

Indigo bunting Passerine cyanea 

Killdeer Charadrius vociferus 

Mallard Anas platymynchos 

Mourning dove Zenaida macroura 

Northern cardinal Cardinalis cardinalis 

Northern flicker Colaptes auratus 

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Northern harrier Circus cyaneus 

Northern mockingbird Mimus polyglottos 

Northern parula Parula Americana 

Northern rough-winged swallow Stelgidopteryx serripennis 

Orchard oriole Icterus spurious 

Osprey Pandion haliaetus2 

(PA Threatened) 

Pileated woodpecker Dryocopus pileatus 

Red-bellied woodpecker Melanerpes carolinus 

Red-tailed hawk Buteo jamaicensis 

Red-winged blackbird Agelaius phoeniceus 

Rock dove Columba livia 

Rose-breasted grosbeak Pheucticus ludovicianus 

Ruby-crowned kinglet Regulus calendula 

Ruby-throated hummingbird Archilochus colubris 

Scarlet tanager Piranga oliacea 

Song sparrow Melospiza melodia 

Spotted sandpiper Actitis macularius 

Tree swallow Tachysineta bicolor 

Tufted titmouse Baeolophus bicolor 

Turkey vulture Cathartes aura 

UND– duck species NA 

UND – flycatcher species NA 

UND – gull species NA 

UND – sparrow species NA 

UND – vulture species NA 

UND – warbler species NA 

UND – wren species NA 

White-breasted nuthatch Sitta carolinensis 

White-throated sparrow Zonotrichia albicollis 

Willow flycatcher Empidonax traillii 

Wood duck Aix sponsa 

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TABLE 3.3.4.1.3-2: AMPHIBIANS AND REPTILES OBSERVED DURING HERP 

SURVEYS (2010-2011) 


American Toad Anaxyrus a. americanus 

Black Rat Snake Pantherophis alleghaniensis 

Bog Turtle Glyptemys muhlenbergii 

Broadhead Skink Plestiodon laticeps 

Bullfrog Lithobates catesbeianus 

Common Map Turtle Graptemys geographica 

Common Musk Turtle Sternotherus odoratus 

Common Snapping Turtle Chelydra s. serpentine 

Eastern Box Turtle Terrapene c. Carolina 

Eastern Fence Lizard Sceloporus undulates hyacinthinus 

Eastern Garter Snake Thamnophis s. sirtalis 

Eastern Milksnake Lampropeltis t. triangulum 

Eastern Painted Turtle Chrysemys p. picta 

Eastern Red-backed Salamander Plethodon cinereus 

Eastern Worm Snake Carphophis a. amoenus 

Five-lined Skink Eumeces fasciatus 

Four-toed Salamander Hemidactylium scutatum 

Fowler’s Toad Anaxyrus fowleri 

Gray Treefrog Hyla versicolor 

Green Frog Lithobates clamitans melanota 

Longtailed Salamander Eurycea longicauda 

Northern Black Racer Coluber c. constrictor 

Northern Brown Snake Storeria dekayi 

Northern Copperhead Agkistrodon contortrix mokasen 

Northern Dusky Salamander Desmognathus fuscus 

Northern Red Salamander Pseudotriton r. ruber 

Northern Slimy Salamander Plethodon glutinosus 

Northern Spring Peeper Pseudacris c. crucifer 

Northern Two-lined Salamander Eurycea bislineata 

Northern Water Snake Nerodia s. sipedon 

Pickerel Frog Lithobates palustris 

Queen Snake Regina septemvittata 

Red-spotted Newt Notophthalmus v. viridescens 

Spiny Softshell Apalone s. spinifera 

Spotted Salamander Ambystoma maculatum 

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Spotted Turtle Clemmys guttata 

Wood Frog Lithobates sylvaticus 

Wood Turtle Glyptemys insculpta 

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3.3.5. Threatened and Endangered Species 


In development of the Muddy Run Project Pre-Application Document, state and federal natural 

resource agencies were queried regarding the potential presence of rare, threatened, and 

endangered species that may be present in the Project Area. 

Birds 

Two bird species were identified by PGC and USFWS, the Bald eagle (Haliaeetus 

leucocephalus), and the Osprey (Pandion haliaetus). The Bald eagle and Osprey are both listed 

as threatened by Pennsylvania. 

Bald eagle (PA Threatened) 

The Pennsylvania listed threatened Bald eagle was identified by PGC as having “historically 

occurred and might presently occur” within the vicinity of the Project boundaries (letter dated 

August 25, 2006). The Important Bird Area Conservation Plan (Cohen 2004) states the species 

uses the Muddy Run “lake” for feeding. PGC also identified a known bald eagle nest on one of 

the Conowingo Islands traversed by the Muddy Run Project transmission line corridor (letter 

dated June 5, 2008). Additionally, PGC noted two known nests on Upper Bear Island, one on 

Piney Island, two on the eastern shore of the Susquehanna River across from Piney Island and 

one on the western shore of the Susquehanna River across from Piney Island, all upstream of the 

Muddy Run Project. 

Bald eagles prefer large rivers and lakes with abundant fisheries stock, which serve as their 

primary food source. Preferred water bodies include those with adjacent banks vegetated with 

mature canopy trees used for perches and for nesting. Nests are primarily constructed in dominant 

mature trees (often pine, sycamore, red oak and red maple), or cliffs near water, but occasionally 

are built on man-made structures. Kleinschmidt (2006) reported that egg laying and incubation 

occur between January and April with fledging occurring as early as mid-June and as late as the 

end of July. 

Regionally, Bald eagles are becoming increasingly abundant and are present throughout the year 

in the Project area. Surveys for bald eagle conducted in 2010 and 2011 found one active nest and 

one communal roost in the Muddy Run Project area (Center for Conservation Biology, URS, and 

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GSE 2012). Also, suitable foraging habitat for bald eagle was identified along the Muddy Run 

reservoir shoreline and Susquehanna River shoreline in the Project area. 

Osprey (PA Threatened) 

The Pennsylvania listed threatened Osprey was identified by PGC as having “historically 

occurred and might presently occur” within the vicinity of the Project boundaries. The species 

uses the Muddy Run Power Reservoir for feeding and nesting ospreys on power line towers are 

visible from Wissler’s Run Overlook in nearby Susquehannock State Park (Cohen 2004). 

Ospreys prefer salt marshes, large inland rivers, lakes, ponds and wetlands bordered by mature 

trees. Given that their diet is primarily fish, they require access to an abundant supply; however, 

they will also take small waterfowl, mammals and carrion. Kleinschmidt (2006) reported that 

preferred foraging habitat by local ospreys were associated with shallow water with low turbidity. 

They tend to nest in dead trees or on other open structures and have locally been observed 

perching on transmissions towers and on island trees. 

Ospreys are found in the Project area during only a portion of the year. Kleinschmidt (2006) 

reported that ospreys migrate into the area in April and depart by the end of September. Winter 

reports of osprey observations were not found; therefore it is presumed that they are only present 

in the Project area during migration and the breeding season. 

Surveys were conducted in the Project area according to Pennsylvania Game Commission 

protocol from April to June in 2010 and 2011 and were augmented with nest monitoring 

activities. Survey methods included visual scans for ospreys and their nests from boat as well as 

observations from land (URS and GSE 2012b and 2012c). 

One active osprey nest was located in the Project area in 2010 and again in 2011 in the same 

location. The single osprey nest was located on the Power Reservoir and potentially fledged at 

least one offspring. Other osprey activity, not conclusively associated with nests, was also 

observed frequently within the Muddy Run Project transmission line corridor during other studies 

related to the Project (URS and GSE 2012d). Most osprey activity occurred in the vicinity of the 

Project transmission line water crossing and involved ospreys using towers on Lower Bear Island 

and in the Muddy Run Pumped Storage facility for perching. In 2011, one pair of osprey started 

the construction of a new nest in late June in a Project tower on the unnamed island adjacent to 

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Turkey Island. However, this nest did not develop further and was abandoned as of June 23, 

2011. 

Reptiles and Amphibians 

Two listed herptile species were identified by USFWS and PFBC. These species are the Bog 

turtle (Glyptemys muhlenbergii) and the Rough green snake (Opheodrys aestivus). 

Bog turtle (PA Endangered and Federal Threatened) 

The bog turtle is a reptile species that is known to occur within southeastern Pennsylvania, 

including York and Lancaster Counties. The bog turtle is listed as threatened by the USFWS 

under the federal Endangered Species Act and as an endangered species by the Commonwealth of 

Pennsylvania. The species is within the range of the Muddy Run Project (letters from USFWS 

and PFBC dated July 27, 2006 and August 18, 2006, respectively). The actual presence of this 

species within Project boundaries is wholly dependent upon the type of wetlands present given 

that this species is a habitat specialist. The omnivorous bog turtle prefers wetlands with cool 

spring water, mucky substrates and hummocky vegetation with an open canopy. Bog turtles 

migrate between hibernation, foraging, basking and reproduction sites, often through forested 

areas and small stream channels. 

Studies were conducted during the spring and summer of 2010 and again in 2011 to identify 

potential habitat for this herpetofaunal species within the Muddy Run Project area (URS and GSE 

2012a). All land areas were searched to identify potential habitats by qualified biologists. Of the 

6 wetlands identified within the Project study area, 4 wetlands were not potential habitat and did 

not warrant further surveys, and 2 wetlands were potential habitat. Bog turtles were found to 

occupy one wetland within the Project study area. 

Rough green snake (PA Endangered) 

The rough green snake (Opheodrys aestivus) is a reptile species that is known to occur within 

southeastern Pennsylvania. The rough green snake is listed in the Commonwealth of 

Pennsylvania as an endangered species. It is recorded in Pennsylvania from southern Chester 

County and Greene County, though recent evidence also places them in Lancaster County near 

the study area. At the very northern portion of its range in the Susquehanna River Valley, this 

snake is an inhabitant of marshes and moist areas near streams, lakes and marshes. It is an 

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arboreal species, preferring particularly dense growth of brush, trees and vines and it forages 

primarily on insects. 

Studies were conducted during the spring and summer of 2010 to identify potential habitat for 

this herpetofaunal species within the Muddy Run Project area (EA, URS, and GSE 2011). All 

land areas were searched by qualified biologists to identify potential habitats. Potential habitat, 

totaling approximately 120 acres, for rough green snake was found in five different locations, 

therefore additional presence-absence surveys were conducted for this species during the 2011 

field season (EA, URS, and GSE 2012). Following the surveys, no rough green snakes were 

identified. 

A total of 38 species of amphibians and reptiles were observed, a remarkably high total for such a 

comparatively small area. While no RGS were encountered, several other species of concern were 

recorded. Federal and state listed species were represented by the Bog Turtle (Glyptemys 

muhlenbergii – Federally threatened and Pennsylvania endangered) and Broadhead Skink 

(Plestiodon laticeps – Pennsylvania Candidate). The following Pennsylvania species of special 

concern (no take/possession) were recorded during the study: Northern Copperhead (Agkistrodon 

contortrix mokasen), Eastern Spiny Softshell (Apalone s. spinifera), Eastern Worm Snake 

(Carphophis a. amoenus), Spotted Turtle (Clemmys guttata), Wood Turtle (Glyptemys insculpta), 

Common Map Turtle (Graptemys geographica), Four-toed Salamander (Hemidactylium 

scutatum), Queen Snake (Regina septemvittata), Eastern Fence Lizard (Sceloporus undulatus), 

and Eastern Box Turtle (Terrapene c. carolina). 

Fish 

In development of the Muddy Run Project PAD, state and federal natural resource agencies were 

queried regarding the potential presence of rare, threatened, and endangered species that may 

occur in the Project Area. The PFBC and USFWS did not identify any threatened and 

endangered fish species for the Muddy Run Project area. This section is based on new 

information pertaining to recent findings under the federal ESA and the potential presence of 

certain species that are listed in Pennsylvania or Maryland, but were not identified in the PAD. 

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Listed fish species include: 

Bowfin 

� Bowfin (Amia calva) – PA, candidate species 

� Hickory shad (A. mediocris)– PA, listed endangered 

� Alewife (A. pseudoharengus)– ESA, candidate species 

� Blueback herring (A.aestivalis) – ESA, candidate species 

� Chesapeake Logperch (Percinia caprodes, P. bimaculata)- MD, listed threatened 

(upstream of Conowingo) 

Bowfin are listed as a candidate species by Pennsylvania. Candidate species are subject to 

management limitations and could be listed as threatened or endangered in the future. Bowfin are 

considered to be rare in Pennsylvania, and prefer heavily vegetated warm lakes and rivers 

(Cooper 1983). The Bowfin’s historic range encompasses the upper Conowingo Pond, as 

evidenced by only two individuals captured in Conowingo Pond in 1974. There are no records of 

bowfin collection or passage from the Conowingo fish lifts. 

Hickory Shad 

Hickory shad are listed as an endangered species by Pennsylvania. The taking, killing, 

possessing, importing to or exporting from the state is prohibited without special permit. Hickory 

shad have passed into Conowingo Pond via the East Fish Lift very infrequently (10 fish from 

1991 - 2009, SRAFRC 2010). One hickory shad was observed in the Holtwood Fish Lift in 1997 

(SRAFRC 1998). From 1972 – 2009, west fish lift records included total catches of 2,416 

hickory shad, but in recent years, few were caught (SRAFRC 2010). In the Conowingo Dam 

tailrace and lower river tributaries, particularly Deer Creek, hickory shad have become relatively 

abundant in the early spring in recent years. Anglers engaged in catch-and-release fishing for 

hickory shad in the Conowingo tailrace cooperate with MDNR and PFBC to provide brood stock 

for tank or hatchery spawning. Hatchery-raised progeny of these individuals are stocked as fry in 

Chesapeake Bay tributaries by MDNR. The PFBC stocks most hickory shad fry out-of-basin, but 

one in-basin location that received hickory shad fry for five years beginning in 2003 was the 

Muddy Creek Fishing Access, just upstream of Muddy Creek, a west shore upper Conowingo 

Pond tributary in York County, PA. As many as 5.4 million hatchery-marked fry were stocked 

annually during the five-year period. Hickory shad fry stocking at Muddy Creek was discontinued 

after 2007. 

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Alewife and Blueback Herring 

In November 2011, NMFS published its Notice of 90-day Finding on a Petition to List Alewife 

(Alosa pseudoharengus) and Blueback Herring (Alosa aestivalis) as Threatened under the ESA 

(76 Federal Register 67652); thereby establishing them as candidate species and initiating 12- 

month status reviews for each species. Alewife and blueback herring are collectively referred to 

as river herring; collections often are not identified to species. Populations of blueback herring 

have been declining in the northeast due to a number of potential causes including habitat loss, 

targeted catch or bycatch at sea via commercial fishing, and increased numbers of striped bass 

and other types of predators (ASMFC 2009). From 1991 through 2009, 706,811 blueback herring 

and 9,106 alewives were passed into Conowingo Pond by the east fish lift, though the annual 

passage counts have been highly variable. Peak passage of blueback herring occurred from 1997 

– 2001. In three years of electrofishing surveys (1999 – 2001) for river herring spawning in small 

tributaries to Conowingo Pond, no river herring were collected. 

Chesapeake Logperch 

Logperch (Percina caprodes) is listed as threatened in Maryland; however, the species present in 

the Susquehanna River has been reclassified as Chesapeake logperch (Percina bimaculata). Near 

(2008) described the long standing use of P. caprodes and P. bimaculata as synonymous, but 

proposed that Chesapeake logperch is a distinct species and that the appropriate name for the 

species is P. bimaculata. Ashton and Near (2010) noted that Chesapeake logperch is listed as 

threatened in Maryland but that the designation is applied to P. caprodes until the state recognizes 

the nomenclature due to recent removal from synonymy with P. bimaculata (Near 2008). 

Chesapeake logperch use a range of habitat including streams, tributary impoundments, and large 

rivers. Ashton and Near (2010) reported extant populations of Chesapeake logperch in the lower 

Susquehanna River (above and below Conowingo Dam) and in the lower reaches of several 

tributaries including Broad, Conowingo, Deer, Northeast, and Octoraro creeks, MD, and Fishing 

Creek, Michael Run, Muddy, and Octoraro creeks, PA. Abundance was considered to be 

infrequent but occasionally locally abundant. In 1996, 211 Chesapeake logperch were captured 

in Conowingo Pond, mostly by seine but also by bottom trawl, trap net, and electrofishing. Seine 

stations with the highest catch rates (catch per station) included Broad Creek, a west shore 

Conowingo Pond tributary in Harford County, MD, and Fishing Creek, an east shore tributary in 

Lancaster County, PA (Normandeau 1997). Additionally, a total of 55 logperch were captured in 

Broad Creek in 1999 and near Frazier Tunnel (Cecil County, MD) (Normandeau 2000). 

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Logperch were also caught in the Conowingo tailrace during West Fish Lift operations in spring 

through at least 2001, typically one or two individuals per year (SRAFRC 1991; 1992; 2002). No 

logperch have been recorded passing into Conowingo Pond by the East Fish Lift since 1997. 

Plants 

PADCNR (letter dated August 23, 2006) identified two Pennsylvania state listed plant species 

and three non-listed plant species of concern known to have historically occurred in the vicinity 

of the Muddy Run Project. These species are listed below. 

� Reflexed flatsedge Cyperus refractus 

� Umbrella magnolia Magnolia tripetala 

� Eastern gama-grass Tripsacum dactyloides 

� Cranefly orchid Tuliparia discolor 

� Netted chainfern Woodwardia areolata 

Although the general habitat for a plant may be present in the Project area, none of these species 

were observed during field studies. 

Reflexed flatsedge (PA endangered) 

Reflexed flatsedge is a perennial graminoid (USDA NRCS 2008). This primarily upland plant 

species (USDA NRCS 2008) prefers an open canopy and sandy soils and is typically associated 

with fields, open dry woods, and barrens (OHDNR 2008). 

Umbrella magnolia (PA threatened) 

Umbrella magnolia is a perennial tree usually found in upland areas, preferring fine to medium 

textured soils that are neutral to slightly acidic. This species has a low tolerance for drought and is 

shade tolerant (USDA NRCS 2008). It is found in rich woods and ravines (FNA 1993+), near 

mountain streams and other wet areas (Kling et al. 2008), and in mesic shaded coves (OHDNR 

2008). 

Eastern gama-grass (PA Undetermined) 

Eastern gama-grass is a perennial graminoid (USDA NRCS 2008). This plant is typically found 

in wetter areas associated with swales, thickets, woodland borders, abandoned fields, wet shores, 

roadsides and limestone glades and prefers an open canopy (Hilty 2008; Slattery et al. 2003; 

USDA NRCS 2008). Soil conditions are generally loam to clay with and range from neutral to 

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acidic (Slattery et al. 2003). In its letter dated June 3, 2008, PADCNR describes the habitat for 

this plant as swamps and wet shores. 

Cranefly orchid (PA Rare) 

Cranefly orchid is a perennial forb (USDA NRCS 2008). This primarily upland plant species is 

found growing in rich well-drained soils within in mixed hardwood forests (Perles et al. 2006; 

USDA NRCS 2008). Cranefly orchid is known to occur within the boundaries of the Ferncliff 

Wildlife and Wildflower Preserve (LYHR 2006). In its letter dated June 3, 2008, PADCNR 

describes the habitat for this plant as deciduous forests and stream banks. 

Netted chainfern (PA non-listed) 

Netted chainfern, a perennial forb, usually occurs in wetlands where moist, acidic soils are found 

(FNA 1993+; MBG 2008; PNHP 2008; USDA NRCS 2008; UTA 2008). Netted chainfern 

occurs in acidic bogs, woodland swamps, thickets, on seeps, siliceous cliffs and ledges, and near 

still water. In its letter dated June 3, 2008, PADCNR describes the habitat for this plant as moist 

or wet woods and acidic bogs. 


Exelon is not proposing any changes to the existing Project operations. The only changes to 

Project facilities include continued maintenance and upgrades to the existing recreational 

facilities. Bald eagles and ospreys have successfully nested in the Project area. Bog turtles are 

documented residents in the Project area. Further consultations with USFWS and PFBC will 

occur regarding the bog turtle population, but no adverse affects to bog turtle as a result of Project 

operations are anticipated. Continued operation of the Muddy Run Project is not expected to 

affect these communities. 

Exelon’s study of avian interactions with the existing transmission line documents the presence of 

several species of large birds in the immediate vicinity of the Muddy Run Project. The study also 

concludes that deadly interactions with transmission lines have not been a common occurrence. 

As the results of the 2010 study indicated, harmful or deadly interaction is rare and considered to 

have minimal effects on larger avian species. 

Bowfin and Chesapeake Logperch fish are not likely to be adversely affected by the continued 

operation of the Project because the species are not known to reside in the Project area. 

Negligible numbers of hickory shad have used the Conowingo east fish lift; thus the Project is not 

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likely to have an adverse effect on hickory shad as a result of impingement and entrainment. 

Currently, alewife and blueback herring are not present in high abundance and their abundance 

has been in decline due to effects unrelated to the Project. Prior to recent declines, blueback 

herring and alewives used habitats in the lower Susquehanna River as well as in Conowingo Pond 

via passage at Conowingo Dam. Assuming increasing abundance during the temporal scope of 

this analysis, there is a minimal adverse effect of impingement and entrainment. Impingement 

during pumping is unlikely given the wide bar rack spacing and depth of intakes. Entrainment of 

immigrating pre-spawn adults, emigrating post-spawn adults, or emigrating juveniles could occur. 

Changes to existing vegetation management practices are not proposed. . 


CEQ regulations define ‘cumulative effects’ as “the impact on the environment which results 

from the incremental impact of the action when added to other past, present, and reasonably 

foreseeable future actions regardless of what agency (Federal or non-Federal) or person 


For this analysis, the action is the relicensing and continued operation of the Muddy Run Project. 

The cumulatively affected resource is RTE species. The geographic scope for this resource is 

defined by FERC in their Revised Scoping Document as the entire Susquehanna River watershed 

and the upper Chesapeake Bay habitat resources. The temporal scope of this analysis includes a 

discussion of the past, present, and reasonably foreseeable future actions, and their effects on the 

resource based on a new license term. 

The potential impact of the Project is associated with whether the continued operation of the 

Muddy Run Project affects rare threatened or endangered (RTE) species and associated habitat of 

the upper Chesapeake Bay and the Lower Susquehanna River, which had already been altered by 

Holtwood Dam (built 1910) and the Conowingo Project (built 1928) when the Project was 

initially constructed in the 1960s. 

ESA listed species have been and continue to be significantly affected by non-Project activities 

such as dam construction and water diversions. Such past, present and reasonably foreseeable 

future actions affect flow, water temperature, channel morphology, sediment, and water quality 

and are described in Section 3.3.2. 

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Bald eagles and ospreys have successfully nested in the Project area. Bog turtles are documented 

residents in the Project area. Continued Project operations are not likely to contribute to 

cumulative effects. 

Bowfin are only known from two records in Conowingo Pond more than 30 years ago; therefore 

Project operations are not likely to contribute to cumulative effects. 

To date negligible numbers of hickory shad have used the east fish lift, and so negligible, if any, 

numbers are present in the vicinity of the Project. Therefore, presently there are no incremental 

effects of entrainment by the Project’s units in pump-back mode. However, actions in the 

foreseeable future could result in increased passage of hickory shad upstream of Conowingo 

Dam. If hickory shad abundance increases, adverse effects of mortality from impingement and 

entrainment by the Muddy Run Project when in pump-back mode could result, but the effects are 

expected to be minor. Impingement during pumping is unlikely given the wide bar rack spacing 

and depth of intakes. Entrainment of immigrating pre-spawn adults, emigrating post-spawn 

adults, or emigrating juveniles could occur. Entrainment potential is dependent upon proximity to 

the intake structure during pump-back operations, though, so the effects are expected to be small. 

Direct estimates were not made for hickory shad, but entrainment estimates for American shad 

ranged from 3.6 to 5.1% for adults, and estimated population entrainment rates for juvenile 

American shad vulnerable to entrainment at Muddy Run during peak emigration times (1700- 

2200 hrs) ranged from 2.9% to 6.6%. Therefore, the cumulative effect of the Project is expected 

to be minor. 

In recent years, negligible numbers of alewife and blueback herring have used the east fish lift, 

and so negligible, if any, numbers are present in the vicinity of the Project. Therefore, currently 

there are no incremental effects of entrainment by the Muddy Run units in pump-back mode. 

However, actions in the foreseeable future could result in increased passage upstream of 

Conowingo dam. Assuming increasing abundance during the temporal scope of this analysis, 

there is a minimal adverse effect of impingement and entrainment. Impingement during pumping 

is unlikely given the wide bar rack spacing and depth of intakes. Entrainment of immigrating 

pre-spawn adults, emigrating post-spawn adults, or emigrating juveniles could occur. 

Entrainment potential is dependent upon proximity to the intake structure during pump-back 

operations, though, so the effects are expected to be small. Direct estimates were not made for 

alewife and blueback herring, but entrainment estimates for American shad ranged from 3.6 to 

5.1% for adults, and estimated population entrainment rates for juvenile American shad 

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vulnerable to entrainment at Muddy Run during peak emigration times (1700-2200 hrs) ranged 

from 2.9% to 6.6%. Entrainment potential is dependent upon proximity to the intake structure 

during pump-back operations, though, so the effects are expected to be small. Therefore, the 

cumulative effect of the Project is expected to be minor. 

In Conowingo Pond, Chesapeake logperch are considered to be locally abundant in specific 

habitats, but interaction with the Project is expected to be limited; therefore Project operations are 

not likely to contribute to cumulative effects. 


Exelon prepared a Bald Eagle Management Plan and a Bog Turtle Management Plan to address 

further actions related to minimizing potential adverse impacts to these species in the Project 

area. For the protection of ospreys from potential disturbances or other impacts during the 

breeding season the following measures will be provided for ospreys nesting on Exelon lands: 

� Nest Buffers - Nest buffers of 330 feet will be implemented during breeding season for 

most activities. For activities with the potential to emit excessive noise (which excludes 

routine Project operation and maintenance activities), larger buffers up to 600 feet will be 

implemented during breeding season. 

� Herbicide application for vegetation control will be avoided within 330 feet of nests 

during breeding season. 

� Tower nests – In the event that nests located in towers are identified as problem nests, 

Exelon will consult with the United States Fish and Wildlife Service to identify the 

appropriate best management practices and obtain applicable permits for nest removal or 

relocation. A typical best management practice for problem nests in towers is the 

installation of nest platforms on towers or nearby. 


Osprey and/or Bald eagle interactions with the transmission lines are potential unavoidable 

adverse impacts associated with the Muddy Run Project. These incidents were documented to be 

rare occurrences, and the effect of the continued operation of the Project is expected to be 

negligible or non-existent. 

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3.3.6. Recreational Resources 

Regional Recreation 


The Muddy Run Project, a pumped storage hydroelectric facility, is situated on the Susquehanna 

River within York and Lancaster counties in Pennsylvania. Muddy Run Reservoir (upper 

reservoir) is located on the eastern shoreline of Conowingo Pond and consists of a 900-acre body 

of water impounding 60,000 acre-feet of water with an average depth of 60 feet. Conowingo 

Pond, which was formed by the damming of the Susquehanna River by the Conowingo Dam near 

Darlington, Maryland, acts as the lower reservoir for the Muddy Run Project. Lands and waters 

within the existing Project boundary comprise approximately 2,790 acres. These lands generally 

extend along the shoreline of Muddy Run Reservoir, and include the Muddy Run powerhouse on 

Conowingo Pond. Project lands also include a primary transmission line which runs 4.25 miles 

from the Muddy Run powerhouse to a switching station at the Peach Bottom Atomic Power 

Station. 

The Muddy Run Project is the second of five FERC projects as you travel upstream along the 

Susquehanna River. The Conowingo Project is downstream of Muddy Run, while the upstream 

projects include, Holtwood, Safe Harbor and York Haven. The Muddy Run Project is an integral 

component of recreation and conservation opportunities in the lower Susquehanna River 

Corridor. In addition to the adjoining FERC projects; County, State, and Federal preservation 

initiatives and recreation facilities create numerous opportunities for public access and recreation. 

Facilities in the vicinity of the Project include scenic overlooks, hiking trails, fishing, state game 

land, nature preserves, picnic areas, campgrounds, boat launches, and environmental centers with 

interpretive displays. Recreation resources and opportunities in the general vicinity of the Project 

were covered extensively in Exelon’s PAD (Exelon 2009), and Exelon’s Recreation Plan (TRC 

and GSE 2012), and the reader is referred to these documents for additional information. 

Project Recreation Facilities 

The existing recreation facilities at the Muddy Run Project are identified on Figure 3.3.6.1-1. 

Muddy Run Park & Campground. The Muddy Run Park and Campground is located in the 

northerly section of the Muddy Run Project boundary and encompasses an area of 800 acres. 

Within these 800 acres is a 100 acre recreation lake, separated from the Muddy Run Power 

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Reservoir by a dam and concrete sill which regulates the water elevation. Access to the park is 

over Bethesda Church Road West, via Holtwood Road, U.S. Route 372. 

The park is owned by Exelon and operated by a vendor. The developed portion of the park is 

located on the west side of the recreation lake and provides both overnight and day use facilities. 

A 189 site campground (148 trailer sites with electric and water hookup, 38 tent sites and three 

primitive group sites) with two dumping stations, two comfort stations, shower and laundry 

facilities, two playgrounds, and a covered picnic pavilion is located on the northerly shoreline of 

the recreation lake. There is also a large area on the east shore of the recreation lake that is 

occasionally used for camping for special events (i.e., rendezvous re-enactors, Native American 

gatherings etc.). Numerous separate facilities are located throughout the park, including a day 

use area with two covered pavilions, two restroom facilities, a boat launch with dock, four 

playgrounds, an outdoor amphitheater, a basketball court, a ball field, a tractor pull area, and 

picnic tables and grills. A non-motorized trail extends around the perimeter of the recreation lake 

(approximately 3.5 miles) and several side trails branch off the trail for access to the pond for 

fishing. 

Boat rentals (canoes, kayaks, paddleboats, rowboats) are available at the park and visitors can 

launch their own boats (launch fee required) at the park boat ramp. The boat ramp provides 

launch opportunities for small boats on the recreation lake (approximately ten feet of ramp is 

below normal pond elevation with a water depth of four feet at the end of the ramp). Gasoline 

powered boats are not allowed on the recreation lake, though electric motors are allowed. 

Swimming is not allowed in the recreation lake. 

A visitor’s information center contains displays (static and interactive) and meeting rooms. The 

center is also used for park related programs and rental functions. Exelon recently renovated the 

interior of the information center and installed new displays and interactive models at an 

investment of $1.1 million. In addition, the park vendor operates a snack bar and campground 

store. Fees are charged for campsites, the boat launch and rentals, and to reserve a pavilion. 

The recreation lake located north of the Power Reservoir offers numerous activities for the public. 

The boat launch offers boat rentals of row boats, paddle boats, kayaks, and canoes. In addition to 

the boating opportunities, the recreation lake has a variety of game fish including crappies, 

catfish, blue gills, sunfish, largemouth and smallmouth bass, carp, as well as trout which are 

stocked four times a year. 

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Wissler’s Run Park. Wissler’s Run Park is located in Lancaster Pennsylvania, on the eastern 

shoreline of Conowingo Pond, just downstream of the Muddy Run Project Powerhouse. The site 

is accessed using the powerhouse access road from River Road. 

The park is owned and managed by Exelon and provides a large open green space area for 

picnicking, bank fishing, and an overlook of the upper Conowingo Pond and islands. The large 

open green space at the park also provides numerous observation points that are ideal for spotting 

Osprey, Great Blue Heron, and Bald Eagle. Improvements at the site include a covered pavilion 

with picnic tables, benches, an informational kiosk, a 450 foot long paved pathway along the river 

bank for angler access, and an ADA portable restroom. A paved 130 space parking lot services 

this site. The facility is open year-round. 

Muddy Run WMA. The Muddy Run WMA is located in Lancaster County, surrounding the 

southern portion of the Muddy Run Power Reservoir. The WMA consists of approximately 800 

acres (Project and non-Project land) owned by Exelon and leased to (and managed by) the PGC. 

The land is managed to provide food and cover for wildlife, which in turn promotes hunting and 

wildlife observation opportunities. Two gravel parking lots, accommodating approximately 40 

vehicles each, are located on Project land off River Road and Furniss Road. A paved parking lot 

on non-Project land on Hilldale Road accommodates approximately 10 vehicles. A gravel 

parking lot off Old River Road, also on non-Project land, provides space for approximately 40 

vehicles. A series of management roads and trails provide access for hunters, hikers, birders, and 

equestrians. 

Adjacent Recreation Facilities 

Susquehannock State Park. The Susquehannock State Park is located in Lancaster County and 

lies just southeast of the Muddy Run Project. The park is owned and managed by the PADCNR 

and encompasses 224 acres outside of the Project boundary. 

The park has numerous amenities including ball fields, playgrounds, pavilions, picnic tables, 

walking and equestrian trails, group tent sites, a historic building, and various overlook sites. The 

overlook areas provide excellent areas to observe a wide variety of bird such as Bald Eagle, 

Osprey, hawks, Black Vultures, and Turkey Vultures. The park also provides ADA accessible 

restroom facilities. 

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Mason Dixon Trail. The Mason Dixon Trail is a 193 mile trail that connects the Appalachian 

Trail with the Brandywine Trail. The trail begins in Cumberland County, PA, travels east 

towards the Susquehanna River where is follows the western shoreline south to Havre de Grace 

before heading across the river and north to its terminus at Chadds Ford, PA. Sections of the 

Mason Dixon trail cross licensee-owned land. Within the Muddy Run Project, the trail crosses 

the transmission parcels located in York County, and travels near several recreation sites in the 

Conowingo Project. The licensee has entered a license agreement with the Mason Dixon Trail 

System, Inc. allowing sections of the trail to be on Project land. 

Conestoga Trail. The Conestoga Trail is a 61 mile trail that begins in Furnace Hills where it 

intersects with the Horse-Shoe Trail, before meandering throughout Lancaster County, 

Pennsylvania before reaching its terminus with the Mason Dixon Trail. Near the Muddy Run 

Project, the trail travels near the northwestern section of the Muddy Run WMA, before travelling 

across Holtwood Road, Route 372 to intersect with the Mason Dixon Trail. 

Informal Recreation Sites 

There are a variety of informal recreation sites within the Project boundary. They mainly consist 

of foot trails to access the recreation reservoir for hiking or fishing. These sites were developed 

over time through regular use but have not been improved by the licensee. 

Use of Formal Recreation Sites 

Exelon conducted an in depth study from March 2008 to March 2009 to assess the character and 

frequency of use at formal recreation sites in the Muddy Run Project. Data collection objectives 

included characterizing types and levels of recreational use within the Project boundary and 

evaluating the potential need for additional access or facilities at the Project. The data was 

obtained using a variety of methods including spot counts, calibrations counts, traffic counters, 

and operator-supplied data. Using these methods, the study was able to obtain usage at sites 

based on recreation days, a recreation day being defined by FERC as each visit by a person to a 

development for recreational purposes during any portion of a 24-hour period. This study yielded 

data on the annual, peak, and seasonal usage at the sites. To determine facility capacity, spot 

checks were taken to observe the amount of used and available parking spots. Percent capacity 

was generally calculated during summer months. 

In addition to the 2008-2009 recreation survey conducted by the licensee, a User Preference 

Survey was conducted from April 2010 to May 2011 at the Muddy Run Project recreation sites to 

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obtain feedback on the quality of recreation facilities within the Project and need for additional 

facilities. Users were asked to give a rating, ranging from poor to excellent, on the parking, 

maintenance, fishing access and overall quality of the facility. In conjunction with the 

development of the Shoreline Management Plan and Recreation Management Plan, public 

meetings were held in June 2011 and September 2011 to further elicit feedback on the need for 

new facilities, and the satisfaction level of the existing recreation facilities. 

The User Preference Survey revealed that the Muddy Run Project was well regarded as a whole, 

averaging an overall score of good across all recreation facilities surveyed. All topics surveyed 

received scores at or above the good mark, with parking and fishing access receiving an average 

score of good, and maintenance receiving a score of good. 

This study found Muddy Run Park to be the most often used Project recreation facility, with 95 

percent of recreational days occurring within the park. The Muddy Run WMA accounts for 3 

percent of recreational trips to the area, while Wissler’s Park accounts for 2 percent. 

Muddy Run Park and Campground. Approximately 254,000 recreation days occurred during 

the year at the Muddy Run Park and Campground based on results from the Exelon study. Peak 

usage of the site was found to be during the summer months, occurring between May 27 and 

August 29. With approximately 44 percent of usage during these months, summer was 

substantially higher than fall, in which 27 percent of use occurred. Spring accounted for 23 

percent of the total use, while winter saw the least use at 5 percent. The peak use weekend 

occurred during the extended July 4 th weekend, when approximately 6,400 recreation days 

occurred at the park. This exceeded the daily average recreation days during summer months, 

which was estimated at approximately 1,200 days. Overall, the most popular activity observed 

was camping, which accounted for 21 percent of recreation days spent at the park. 

Camping is a popular activity at Muddy Run Park. Based on campground data, an estimated 21% 

of all the recreation days spent at the park are coupled with overnight stays (camping). 

Participation rates varied by season: 27% of all visitors to the park in the spring also stayed in the 

campground, while just 12% camped in the fall. However, after adjusting for the short fall season 

and comparing September numbers only, the participation rate for camping climbs to 28% for the 

beginning of fall. In the winter and summer, participation rates for camping are slightly lower, at 

22% and 23%, respectively. 

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Estimates for day-time recreational activity for the spring, summer and fall seasons were provided 

by park staff. Picnicking (50%) and boating (20%) were popular activities during spring. 

Picnicking and boating were the high use activities for both summer and fall seasons, as well as 

on an annual basis. During the winter season, spot counts and calibrations were used to collect 

data on recreational activity at Muddy Run Park. The majority of the activity was divided fairly 

evenly between three types of recreational use: walking or running (33%), sightseeing (33%), and 

shoreline fishing (32%). Boating, birding, and “other” activities were also observed, but each 

accounted for less than 1% of the total activity noted at the site during the winter months. 

Based on information provided by the Muddy Run Park staff and observation of parking usage, 

the park is considered well utilized, but not over capacity. Throughout the park as a whole during 

the summer season, the average use is at 60 percent capacity, based on parking lot usage. The 

greatest usage was at Picnic Area D (80 percent capacity), while the least utilized area of the park 

was Picnic Area B, which saw 30 percent capacity used. 

The User Preference Survey identified that 96% of those surveyed rated the overall facilities at 

Muddy Run Park as good or excellent, with opinion divided generally equally between the two 

ratings at 49% and 47%, respectively. Less than 5% of the respondents rated the overall facilities 

as fair or poor. No one rated the location as average. The average rating for the site as a whole 

was between good and excellent. 

At Muddy Run Park, the comment received most frequently (27%) was that a swimming pool 

within the park or a roped-off swimming area at the recreation reservoir was desired by 

recreationists. Currently, swimming and wading are not permitted at any location within the 

recreational facility. Of the comments received, 14% requested additional shower facilities or 

improvements to the existing ones. 

Specific comments received addressed a variety of issues. Twelve percent of the comments were 

related to the water and electric hookups at the campsites. Several of the campers noted that 

closer hookups would be appreciated. The addition of sewer hookups was also mentioned. Rental 

cabins or campers were requested by 7% of the recreationists surveyed at the facility. 

Muddy Run WMA. The Muddy Run WMA was less utilized than the Muddy Run Park, with 

approximately 7,500 daytime recreational days from March 2008 to March 2009. The study 

found no nighttime usage, which would have been indicated by camping activity, in the Muddy 

Run WMA. 

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At the WMA, hunting was the most popular activity (46%). In the winter, 77% of the 

recreationists at the area were hunting. Hunting was also popular in the fall, with 58% of the 

visitors. Running and walking were engaged in by 29% of total recreationists during the 2008- 

2009 season. This was the most popular activity in the summer, with 73% of the visitors 

participating. Birding was the most commonly observed activity in the Wildlife Management 

Area during the spring, with half of the visitors participating. Annually, however, the activity 

represents just 13% of the recreational use. Horseback riding (5%) and “other” activities (2%) 

were also noted at the WMA. 

The User Preference Survey identified horseback riding and walking during the 2010-2011 

survey period. The majority of the visitors to the site reported being very pleased with the 

facilities. Of the recreationists surveyed, more than 80% rated the overall site as excellent or 

good. None of the individuals interviewed assigned a rating of fair or poor to the location. The 

average rating for the site as a whole was good to excellent. Maintenance at the Muddy Run 

WMA was rated the highest of the areas addressed, with an average score of good to excellent. 

Parking received an average rating of good. For all of the areas surveyed, the recreational users 

of the WMA viewed the area as average or better. 

Wissler’s Run Park. An estimated 5,800 daytime recreation days were spent in Wissler’s Run 

Park from March 2008 to March 2009. The park saw its greatest usage during the spring season, 

with 52 percent of all recreation days occurring during these months. The summer season saw 35 

percent of total usage, while fall and winter usage was much less at 9 percent and 4 percent, 

respectively. While the park was used most in the spring, the peak use weekend was found to be 

the July 4 th weekend. During this time, approximately 200 recreation days were spent at the park. 

This was much higher than the average recreation days spent throughout the year, which was 

estimated to be around 20. 

Sightseeing was the most popular activity (71%) at Wissler’s Run Park during the 2008-2009 

recreation season as a whole, as well as during each season individually. Twenty-one (21) percent 

of recreationists engaged in shoreline fishing during the 2008-2009 season. This figure rose in the 

summer to 37% of the visitors to the park. Picnicking, birding, boating, and “other activities” 

combined represented only less than one-tenth of the total recreation activity at Wissler’s Run 

Park. In the fall, however, birding increased in popularity, including 18% of the visitors. 

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The User Preference Survey identified fishing and walking as the activities observed during the 

2010-2011 survey period. Eighty percent of the recreationists who completed the questionnaire 

rated the overall facilities at the site as excellent or good. None of the respondents rated the 

overall facilities as fair or poor. Parking received the highest average rating, from good to 

excellent. Maintenance and fishing each received an average rating of good. For all of the aspects 

of the park that were evaluated, the ratings were higher in the summer than in the spring. Fishing 

has the largest variation in rankings across the seasons. Visitors to the facility rated fishing fair in 

the spring, while the summer average rating was considerably higher at good to excellent. 

Projection of Project Recreation Demands 

To evaluate the ability of the facilities at the Muddy Run Project to meet future recreation 

demands, estimates were made through the year 2050 of growth in recreation days by activity at 

each location. The projections are based on growth coefficients developed as part of Projections 

of Outdoor Recreation Participation to 2050, published by the USDA Forest Service. The USDA 

projections use a combination of population, income, age, gender, and ethnicity to develop 

projected regional growth rates for various recreational activities. Table 3.3.6.1-1 presents the 

activity-specific growth rates. 

As shown above, the regional activities that the Forest Service anticipates will have the greatest 

increases in demand are horseback riding (82% growth), canoeing or kayaking (60%), birding 

(49% growth), sightseeing (48%), and biking (44%). The lowest growth rates are projected for 

general boating (17%), picnicking (17%), and hunting (12%). 

These growth coefficients were used to Project potential Muddy Run recreation activity by site 

through 2050. Recreational use from Section 6.4 of the Recreation Study provides the baseline 

2008 numbers from which the projections were made. Table 3.3.6.1-2 presents the projected 

number of recreation days for the year 2050 by activity for each site in the Muddy Run Project. 

As shown in Table 3.3.6.1-1 and Table 3.3.6.1-2, the participation rates will change over time as 

the level of growth varies from activity to activity. The majority of Project use will still be 

related to Muddy Run Park due to the size of the facility, the opportunities for a variety of 

activities and facilities, and the presence of on-site staff. 

Project-wide, recreation demand, in terms of recreation days, is projected to increase by 24% 

from 267,629 in 2008 to 331,454 in 2050. 

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Projection of Facility Capacity 

The site specific growth rates presented above are the basis for projecting 2050 capacity demand 

figures, in terms of average summer weekend use. Table 3.3.6.1-3 presents the level of capacity 

projected for 2050 at each site within the Muddy Run Project. As shown in Table 3.3.6.1-2, it is 

projected that the recreation sites at the Muddy Run Project will be under-capacity on the average 

summer weekend in 2050. The WMA and Wissler’s Run Park will continue to be extremely 

underutilized, while Muddy Run Park will exceed 75% of capacity. 

For each recreation resource type, the growth presented in the table above includes increases in 

demands from all types of recreation. While picnicking is expected to increase at approximately 

17% over the next four decades, sightseeing is anticipated to grow much more quickly (48%). 

Therefore, the growth in sightseeing will place additional demands on a facility that is also used 

by those picnicking. 

By 2050, it is projected that Muddy Run Park facility use will average 77% on weekend summer 

days. Other facilities (WMA and Wissler’s Run Park) will continue to be underutilized. While 

individual lots at Muddy Run Park may be more heavily used during certain seasons and special 

events, ample opportunities will be available for recreationists to enjoy any of the recreation 

resource types the park offers. With other Project sites underutilized, it would be expected that as 

demand pressures rose at the more heavily utilized (in terms of percentages) areas, recreationists 

would simply shift to facilities with more capacity. 


The analysis of Project Effects associated with the continued operation of the Muddy Run Project 

under a new license provided in this section includes a description of the anticipated effects of 

Exelon’s proposed Project, which includes Exelon’s proposed PM&E measures. 

Exelon’s relicensing studies determined that the existing recreational facilities are adequate to 

meet recreational demand associated with the Project now and in the reasonably foreseeable 

future. However, some of the facilities are currently in need of upgrading to maintain the proper 

functioning condition of the facility and to provide for ADA accessibility, or will require 

replacement or rehabilitation during the term of the new license to maintain the facilities in 

proper functioning condition. 

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Exelon’s proposed Project includes a Recreation Plan. The primary goal of the plan is to manage 

public recreation use of the Project’s recreation facilities over the term of the new license, and 

minimize recreation-use impacts to natural, historic, and cultural resources within the Project 

Area. The plan includes the following objectives to help achieve this goal: 

� Inventory existing access and facilities. 

� Estimate existing and potential recreational use of the Project. 

� Assess the need for additional public recreational access, opportunities and facilities. 

� Determine enhancements to existing facilities and any new facilities needed to meet 

recreational demand. 

� Determine the cost associated with rehabilitation and development of the evaluated 

facilities and identify entities responsible for implementing, constructing, operating, or 

maintaining any existing or proposed measures or facilities. 

� Determine how the Project can be integrated with existing or proposed regional 

recreation plans. 

� Address public access, safety and recreation with respect to blocked and impeded access 

and fluctuating water levels. 

The plan includes the following primary sections: 

Section 1-4 – Introduction, Purpose, Project Description, and FERC Requirements. 

Section 5 – Existing Public Recreation and Access. This section describes existing Project 

and regional recreation resources, and facilities. 

Section 6 – Estimate of Project Recreation Use. This section documents existing Project 

recreational facility use. 

Section 7 – Projected Recreation Demands. This section provides an analysis and estimate of 

future use of the existing Project recreational facilities. 

Section 8 – Recommendations and Proposed Enhancements. This section describes the 

Project’s proposed recreation rehabilitation of existing recreation facilities and capital 

improvement measures. 

Section 9 – Recreation Management. This section describes the recreation-monitoring 

program that defines how Project recreation facilities, use, needs, and potential associated 

impacts will be monitored and addressed over the license term. 

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Exelon also incorporates measures regarding erosion control during construction of recreation 

facilities through the implementation of a Shoreline Management Plan for the new license. The 

measures require that Exelon develop in consultation with appropriate agencies and, if required, 

file with FERC construction erosion control and site restoration plans for recreation facilities 

work prior to any ground disturbing activity. The Shoreline Management Plan also provides 

guidance on whether the site requires revegetation or other management measures to address 

erosion. 

Provided below is an assessment of the effects related to recreation resources and how Exelon 

proposes to address them over the new license term. 

The Muddy Run Project provides developed hiking, camping, fishing, boating, picnicking 

(including group picnicking), and sightseeing opportunities at three developed recreation areas on 

the Muddy Run upper recreation reservoir and on Conowingo Pond. The overall condition of the 

recreation area facilities is good. Current facility capacities do not exceed 75% at any of the 

individual facilities. Projected growth rates through 2050 for the existing recreation activities 

present at the Project indicate that current capacity will not be exceeded at any of the individual 

facilities. Based on the condition of the facilities and overall and weekend occupancy levels at 

each of the three facilities in the Project, the existing facilities should be adequate to handle an 

increase in use over the new license term with routine maintenance and upgrades to the facilities. 


While the recreation facilities at the Muddy Run Project have shown to meet current and future 

recreational demands, Exelon has proposed to improve several sites at the Project. In addition to 

site improvements, Exelon will also continue its existing partnerships and contracts with vendors 

to operate and maintain the existing recreation facilities. Specific improvements proposed for the 

recreational facilities for the new license are as follows. 

The estimated cost for this overall recreation improvement proposal is approximately $2 million 

dollars. Specific costs are provided in Table 3.3.6.2-1. 

Muddy Run Park Enhancements 

The campground includes 148 camper trailer sites with water and electric hook-ups. Presently, 

137 of these sites have 30 amp electric hook-ups. Eleven sites with 50 amp hook-ups were 

upgraded within the past three years to accommodate newer camper trailers that are wired for 50 

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amp service. The demand for 50 amp campsites exceeds the current supply of such sites. Exelon 

will upgrade the electric service to an additional 50 campsites, and monitor future need and 

upgrade additional sites when the demand exists. 

Exelon will expand an existing playground area near the Visitor’s Center with safety swings and 

three modular play structures suitable for younger children (“tot lot”). A mulch safety surface 

will also be installed. A 2,000 square foot water spray park will be constructed near the Park 

entrance. The spray park will help address the absence of permitted water contact activities at the 

Park as swimming is not allowed in the recreation lake. 

The existing boat launch facility will be replaced with a new concrete plank ramp with a new 

gangway and floating dock. The ramp is sized for launching small trailered watercraft suitable 

for boating on the recreation lake (electric motors only). The ramp will be 12 feet wide and of a 

length to provide a water depth of three feet at the toe of the ramp. Docking will consist of a 

concrete gangway abutment, three foot wide gangway, and an 80 inch wide dock of sufficient 

length. The gangway and dock will be ADA compliant. 

A small ADA picnic area adjacent to the boat launch facility will be upgraded to improve the 

stability and firmness of the surface and drainage. Renovations to this area will enhance access 

and reduce future maintenance to this site. 

Approximately 150 feet of shoreline between the ADA picnic area and the rental boat dock will 

be improved to control run-off and potential erosion into the recreation lake. This will be 

accomplished by removing the boulders from the area, re-grading, and applying a crushed gravel 

base to prevent further shoreline erosion. 

The existing timber retaining wall along the shoreline at the rental boat dock area will be removed 

and replaced with a sheet pile retaining wall. A new ADA gangway and floating dock will also 

be installed. The retaining wall is being replaced as the existing wall is being undermined by the 

action of the lake. 

Wissler’s Park Enhancements 

Some facilities at Wissler’s Park have recently been renovated to improve their condition. This 

includes the paved walkway from the parking area to the picnic pavilion. The parking lot was 

repaved in 2011. The pavilion has recently been replaced. 

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Exelon plans to designate and sign two additional ADA parking spaces near the picnic pavilion 

for compliance with standards set by ADAAG. A non-functioning fish cleaning station will be 

demolished and the site reclaimed. In addition, the existing walkway along the top of bank will 

be rebuilt and repaved. The Rawlinsville Fire Department has requested that Exelon construct an 

emergency access boat launch immediately south of the existing facility on lands within the 

Project boundary but not owned by Exelon. This boat launch would be used by the Fire 

Department to access the river during emergency situations. Rawlinsville Fire Department has 

agreed to consult with the property owner (Norfolk Southern) to obtain permission to construct 

the requested emergency access, which will be secured to assure that it is used by authorized 

personnel during emergencies. 

Wildlife Management Area 

Pursuant to license Article 41, Exelon leases lands to PGC, which is managed to provide food and 

cover plantings for wildlife, and provide public hunting opportunities. Exelon proposes to 

continue this arrangement with PGC. 


No unavoidable adverse impacts are expected to recreational resources in the Muddy Run 

Pumped Storage Project. In areas where recreation enhancements are proposed, temporary 

impacts may result as a result of construction. These impacts are expected to be short term and as 

a result, no long term adverse impacts are expected in association with the licensing proposal. 

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TABLE 3.3.6.1-1: RECREATION PROJECTION INDEX, THROUGH 2050 (A) 

NORTHEAST REGION 

Recreation Resource 

Type 2000 2008 (b) 2010 2050 

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Growth Factor, 

2008 to 2050 

Boating—general 1.00 1.02 1.03 1.20 1.17 

Canoeing 1.00 1.11 1.14 1.78 1.60 

Biking 1.01 1.08 1.09 1.55 1.44 

Shoreline Fishing 1.00 1.04 1.05 1.29 1.24 

Picnic 1.00 1.06 1.07 1.23 1.17 

Walking-Running 1.04 1.12 1.14 1.52 1.36 

Camping 1.00 1.0 1.09 1.32 1.32 

Hunting 0.98 1.00 1.01 1.12 1.12 

Horseback Riding 1.03 1.12 1.14 2.03 1.82 

Sight-seeing 1.04 1.22 1.27 1.80 1.48 

Birding 1.04 1.18 1.22 1.76 1.49 

� Source: Bowker, J. M., Donald B. K. English, H. Ken Cordell. Projections of Outdoor Recreation 

Participation to 2050, published by the USDA Forest Service, Athens, GA. 

� Interpolated from the projected change between 2000 and 2010.



TABLE 3.3.6.1-2: RECREATION ACTIVITY IN TERMS OF RECREATION DAYS BY LOCATION, SUMMARY, 2050 (A) MUDDY RUN PROJECT 

Boating 

Shoreline 

Fishing 

Picnic 

Walking/ 

Running 

Birding Hunting Horseback 

Riding 

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Sightseeing 

Camp Other Total 

Muddy Run 

Park 

67,022 27,161 126,369 51,057 17,963 0 0 0 

20 

23,540 313,112 23% 

Muddy Run 

WMA 

0 0 0 2,974 1,441 3,863 724 543 0 206 9,751 30% 

Wissler’s 

Run Park 

53 1,570 194 0 127 0 0 6,358 0 289 8,591 42% 

Total 67,075 28,731 126,563 54,031 19,531 3,863 724 6,901 

24,035 331,454 24% 

Participation 

Rate 

20% 9% 38% 16% 6% 1%



TABLE 3.3.6.1-3: PROJECTED AVERAGE WEEKEND SUMMER PARKING LOT USE BY 

LOCATION, SUMMARY, 2050 MUDDY RUN PROJECT 

Available 2008 Average 

Projected 2050 

Average Summer Projected Percentage 

Spaces Summer Use Use (a) 

of Use 2050 (a) 

Muddy Run Park 582 338 450 77% 

Muddy Run WMA 80 3 4 5% 

Wissler’s Run Park 130 3 5 4% 

Total 792 344 459 58% 

(a) Based on growth rates presented in last column of Table 3.3.6.1-1. 

TABLE 3.3.6.2-1: RECREATION FACILITY ENHANCEMENT COSTS 

Facility Construction Cost Annual O&M Cost 

(2014 costs) 

(2014 costs) 

Replace Muddy Run Park Boat Ramp and Dock $60, 000 $1,000 

Upgrade Muddy Run Park ADA Picnic Site $11,000 $500 

Shoreline Stabilization at Recreation Lake $7,000 $500 

Replace Retaining Wall at Boat Rental Area $289,000 $500 

Electric Upgrade Service to 50 amp $444,000 $30,000 

Playground Expansion at Muddy Run Park $45,000 $1,500 

Construct Spray Park at Muddy Run Park $346,000 $12,000 

Wi-Fi Service at Muddy Run Park $79,000 $15,000 

New Paving $764,000 $5,000 

Total Muddy Run Park $2,045,000 $66,000 

Wissler’s Run Park Repairs $16,000 $2,500 

Total Wissler’s Run Park $16,000 $2,500 

TOTAL MUDDY RUN PROJECT $2,061,000 $68,500 

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3.3.7. Land Use 


The Muddy Run Project is located in Lancaster and York counties, Pennsylvania. The majority of Project 

land is located in Lancaster County, including the 900 acre Power Reservoir, and the 100 acre recreation 

lake. A transmission line corridor spans across the Susquehanna River and extends into York County. In 

total, the Project consists of approximately 2,790 acres, 1,790 acres of which are upland. The majority of 

upland in the Project consists of agriculture fields and forested land. The land within the Project 

boundary is used for Project operation, public access, recreational use, and for various wildlife/nature 

protection and management. To better manage the Project land, Exelon has classified land use throughout 

the Project boundary on the basis of its primary land use. 

Existing Land Use 

Exelon has defined three land classifications within the FERC Project boundary (Figure 3.3.7.1-1). These 

classifications are defined as: 

� Project Operations – Lands used for power generation and electric transmission/distribution 

infrastructure and purposes. 

� Developed Recreation – Lands managed for developed public recreational facilities and activities. 

This includes commercial recreation facilities. 

� Public Access Lands – Lands generally open to the public but that are managed by a federal, state, 

county or conservation entity. 

Approximately 24 percent of land in the Project boundary is considered Project Operations land. The 425 

acres that make up this class are generally located along the shore of the Power Reservoir, and along the 

transmission line parcels which extend from the Muddy Run Powerhouse, across the Susquehanna and 

south into York County. 

Developed Recreation comprises 667 acres, or 37 percent of the upland acreage in the Project boundary. 

Muddy Run Park accounts for the majority of the acreage (~660 acres), while Wissler’s Park 

encompasses approximately 7 acres. Public Access Lands accounts for the remaining 39 percent of 

upland land, totaling 701 acres. The Muddy Run WMA makes up the majority of this class. 

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Special Designated Areas 



Portions of land within and adjacent to the Project are included within various national and statewide 

programs dedicated to promoting outdoor recreation needs, as well as the conservation and protection of 

the natural environment. 

National Trails System 

The National Trail System Act of 1968 authorized creation of a trail system comprised of National 

Recreational Trails, National Scenic Trails, and National Historic Trails. National Recreation Trails may 

be designated by the Secretary of Interior or the Secretary of Agriculture to recognize exemplary trails of 

local and regional significance in response to an application from the trail’s managing agency or 

organization. Portions of the Susquehanna River Trail and Mason-Dixon Trail are designated as National 

Recreation Trails as administered by the National Parks Service and are adjacent to the Project. A 

segment of the Mason-Dixon Trail (not part of the National Recreational Trail) crosses the Project’s 

transmission lines within the Project boundary. This segment is maintained and managed under an 

agreement with Exelon by Mason-Dixon Trail System, Inc., a volunteer organization dedicated to 

maintaining the Mason Dixon Trail system. 

Statewide Water Protection 

All surface waters in Pennsylvania are protected for aquatic life, water supply (potable, industrial, 

livestock, wildlife, and irrigation), and recreation (boating, fishing, water contact sports, and aesthetics). 

Pennsylvania has assigned a warm water fishes aquatic life designated water use to the Muddy Run 

Generating Reservoir, and a trout stocking designated use for the Muddy Run Recreation Lake. In 

addition to narrative standards that are applicable to all surface waters, specific water criteria for 

parameters such as pH, alkalinity, bacteria, color, dissolved oxygen, temperature, and certain ions, metals, 

and nutrients are established for critical uses in Pennsylvania. 

Pennsylvania Natural Heritage Program 

The Pennsylvania Natural Heritage Program is a partnership between the Western Pennsylvania 

Conservancy, PADCNR, PFBC, and PGC that gathers and provides information on the location and status 

of important ecological resources such as plants, vertebrates, invertebrates, natural communities, and 

geologic features. Within the Project, the Conowingo Islands were rated “exceptional” based on its 

potential natural value. Other areas rated under the program include Wissler Run (rated “high”) and 

Muddy Run Reservoir (rated “notable”). 

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Exelon has prepared a SMP to provide a framework for the management of Project lands and river 

shoreline areas consistent with broader local, regional, state and federal regulations, initiative, and 

planning guidelines. This SMP enables Exelon to fulfill its license responsibilities and obligation for the 

Project, including the protection and enhancement of the Project’s environmental and recreational assets. 

The SMP outlines the measures Exelon has taken to minimize or eliminate negative effects to shoreline 

resources through programs and policies consistent with FERC regulations. The measures created to 

manage Project land are described below: 

General Policy. To accommodate safe uses of lands and waters within the Project boundary by the 

general public, Exelon maintains designated recreational areas for public recreation including formal 

camping, picnicking, hiking, fishing and other day-use activities. All other Exelon owned lands, except 

where specifically posted, are available for informal day use activities. 

Due to the substantial daily upper reservoir water level fluctuations inherent in the operation of a pumped 

storage hydroelectric facility, access to the upper reservoir remains restricted by Exelon in order to ensure 

that public safety and plant operational and security concerns are met. 

Shoreline Erosion Control. Existing shoreline vegetation will be maintained for shoreline stabilization 

and to act as a vegetation buffer between the shoreline and adjacent land use. However, modifications are 

allowed to shoreline vegetation in order to construct erosion control measures, provided the modifications 

do not impair the overall function of the vegetated buffer. Trees and shrubs on steep slopes will be 

maintained whenever possible. If the buffer function would be impaired, a planting plan, using the native 

species plant list provided in the SMP will be devised and implemented to mitigate for the reduced 

function of the disturbed shoreline. 

General Maintenance. Modifications are allowed to shoreline vegetation to maintain the health of the 

shoreline vegetation, provided the modifications do not impair the overall function of the vegetated 

buffer. Dead, dying, diseased or hazardous trees and shrubs may be removed. In addition, non-native 

invasive vegetation may be removed. If the buffer function would be impaired by vegetation removal, a 

planting plan will be devised and implemented to mitigate for the reduced function of the disturbed 

shoreline. 

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Woody Debris Management. Woody debris is defined as trees and woody material that extend from the 

shoreline into the impoundment. This material can provide important habitat for fish and wildlife and 

shall be left in place unless the debris is a navigational or safety hazard. 

Game Species Management Policy. Exelon leases approximately 800 acres of both Project and non- 

Project land around the Power Reservoir to the PGC, which manages the property as a WMA. The 

Muddy Run WMA is managed by the state to improve wildlife habitat and provide public recreation 

opportunities, including hunting. Exelon has proposed to continue this arrangement with the PGC. 

Exelon and the PGC partner to manage the white-tailed deer population at Muddy Run Park and the 

recreation reservoir to maintain a healthy and sustainable population based on environmental and habitat 

conditions. This may include limited or restricted hunting opportunities conducted under conditions that 

ensure the safety of other recreationists. 

Sensitive Natural Resource Protection Overlays and Policies. Research and numerous studies were 

conducted to assess and determine the existence of and potential effects of Project operations on various 

resources, including RTE species, terrestrial and aquatic habitat, historic and cultural sites and structures, 

wetlands, unique natural areas, and steep slopes. 

Exelon has compiled existing and new data on these resources to develop a “sensitive resources” overlay 

to apply to the three land use categories described above (Figure 3.3.7.1-2). This overlay is defined as 

areas within the Project boundary that contain resources protected by state or federal law or executive 

order, and other natural features that Exelon considers important to the area or natural environment. The 

presence of these resources may partially or completely limit or restrict land uses and/or development, 

regardless of the applicable land classification described above. 

The sensitive resource overlay data will be updated as resources are verified and as new information and 

data is collected from documented and verified sources. Exelon may use specific resource data from the 

overlay to designate resource sites and buffer areas for conservation, preservation, and protection 

purposes. 

Prior to the implementation of any proposed expanded or new use of Project lands by Exelon or a non- 

licensee, Exelon will determine if the potential use would affect any sensitive resources identified on the 

overlay. Exelon will survey, or require the non-licensee proposing a non-Project use of Project lands to 

survey, the affected land to determine if it hosts any sensitive resources not previously verified or 

identified. If any sensitive resources are identified, Exelon will take appropriate protective actions prior to 

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undertaking the proposed use, or require a non-licensee proposing to use Project lands to take the same 

measures as a condition of conveying the right to use or occupy Project lands. In either case (Exelon or 

non-licensee) will develop protective actions in consultation with appropriate resource agencies. 

Resources with individual management plans and policies which are also subject to the Sensitive 

Resource Protection Overlay are identified in the following subsections. 

Leased Premises Policy. Exelon will continue existing leases for lands and structures within the Project 

boundary. Existing leases include the WMA with PGC, the lease for cultivation, and the manager’s 

residence at Muddy Run Park. 

Requests for new lease opportunities, or expansion of existing leases, will be reviewed by Exelon on a 

case-by-case basis to ensure requested uses comply with all regulatory requirements and Exelon policies, 

and do not impair Project operations, adversely impact sensitive resources, or unduly restrict public 

access. 

Policy Restricting Certain Recreational Uses. Exelon provides public recreation and access to Project 

lands and waters pursuant to its FERC license requirements. Access and use of certain portions of Project 

lands is restricted for operational, safety and security reasons. These restrictions include: 

Fishing: Fishing currently is not allowed within the secure area near the powerhouse along Conowingo 

Pond or the Power Reservoir, although fishing is allowed under State regulations from the River Road 

(public road) bridge over the Power Reservoir canal. Fishing in Project waters accessible to the public 

will be governed by applicable state regulations. 

Hunting: Hunting will not be allowed within the secure area of the Power Reservoir, or on other Project 

lands posted against hunting by Exelon, as necessary, to protect the public, adjacent landowners, lessees, 

employees, sensitive resources, and Licensee’s operating capabilities. Hunting on Project lands 

accessible to the public will be governed by Exelon policies and applicable state regulations. 

Off-Road Vehicles: Use of off-road vehicles on Project lands is prohibited. Exceptions may be made for 

company related purposes for employees and contractors, emergency personnel, agency personnel during 

their normal duties, and instances where an off-road vehicle is needed for ADA access for an approved 

activity or use. 

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Approval of Non-Project Use of Project Lands 

Any use of and/or construction within the Project boundary by a non-licensee must be permitted by the 

appropriate agencies and receive Exelon approval before work can begin. Parties requesting non-Project 

use of Project lands will be required to provide Exelon with sufficient information for Exelon to 

determine if the proposed use or occupancy is consistent with the requirements of the Project license and 

otherwise consistent with Exelon’s applicable policies. Exelon will determine if the proposed use or 

occupancy may be approved pursuant to the standard FERC use or occupancy article or whether prior 

approval by FERC is required. If Exelon, in its discretion, decides to support the proposed use or 

occupancy, it will execute the necessary conveyance of rights when it has received any necessary 

approval from FERC and the non-licensee has obtained all necessary permits and approvals. 

In addition to the SMP developed by Exelon, a Recreation Management Plan was developed to manage 

the recreation sites associated with the Project. The RMP provides a comprehensive overview of public 

recreational use and needs for the Project and addresses the licensee’s responsibilities pursuant to 18 

CFR, Chapter 1, Subchapter A, Part 2, Section 2.7. The RMP also includes a report of recreation 

resources discussing existing and proposed recreational facilities and opportunities at the Project pursuant 

to 18 CFR, Chapter 1, Subchapter B, Part 4, Subpart F, Section 4.51 (f)(5). 


The continued operation of the Muddy Run Project will have little effect on current land use within the 

Project boundary. Adjacent land use to the Project is currently dominated by agricultural land and 

forested land. As the Project maintains this character and promotes public interaction with the 

surrounding nature through parks and the continued presence of a wildlife management area, existing land 

use is not impacted by continued Project operations. While a large portion of shoreline in the power 

generating reservoir is considered Project operation land and therefore restricts public access due to safety 

issues, adequate recreation land is provided in the adjoining recreation lake. 

3.3.7.3 Environmental Measures 

Several recreation enhancements are currently proposed by the licensee for the Muddy Run Project. 

These enhancements are planned to either update existing recreation facilities, or construct new amenities 

on land currently used as developed recreation. As the land use acreage dedicated to recreation and 

public access is more than adequate given the size of the Project, no further environmental measures are 

being proposed in relation to land use by the licensee. 

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No unavoidable adverse impacts are expected to land use in the Muddy Run Pumped Storage Project. 

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3.3.8. Cultural Resources 

Section 106 of the National Historic Preservation Act of 1966 (Section 106), as amended, requires that 

FERC evaluate the potential effects of continued operation of the Muddy Run Pumped Storage Project on 

properties listed in or eligible for listing in the NRHP. Properties listed in or eligible for listing in the 

National Register are called historic properties. Section 106 also requires that FERC seek concurrence 

with the Pennsylvania State Historic Preservation Officer (SHPO) on any finding of effects, and allow the 

Advisory Council on Historic Preservation an opportunity to comment on any finding of effects to 

historic properties. 

If Native American (i.e., aboriginal) properties have been identified, Section 106 also requires that the 

Commission consult with interested Indian tribes that might attach religious or cultural significance to 

such properties. In this case, FERC must take into account whether any historic property could be 

affected by a proposed new license within the Project's area of potential effects (APE), and allow the 

Council an opportunity to comment prior to issuance of any new license for the Project. If Native 

American (i.e., aboriginal) properties are identified, Section 106 also requires that the Commission 

consult with interested Indian tribes that might attach religious or cultural significance to such properties. 

None have been identified at the Muddy Run Project. 


The APE is defined as the geographic area or areas within which an undertaking (i.e., relicensing) may 

directly or indirectly cause alterations in the character or use of historic properties, if any such properties 

exist. The Project’s APE includes all lands within the currently approved Project Boundary and any other 

area outside of the Project Boundary where historic properties might be affected by Project-related 

activities that are conducted in compliance with the FERC license. 

The Muddy Run Project APE includes all the lands within the proposed FERC Project Boundary, as 

shown on Figure 3.3.8.1-1. 

The Muddy Run Project is located in Lancaster and York counties, Pennsylvania. The majority of the 

Muddy Run Project area is located on the eastern shoreline of Conowingo Pond with the Project boundary 

generally extending along the shoreline of Muddy Run Reservoir. The Conowingo Pond is the reservoir 

formed by the damming of the Susquehanna River by the Conowingo Dam near Darlington, Maryland 

which acts as the lower reservoir for the Muddy Run Reservoir. The drainage area upstream of 

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Conowingo Dam is 27,100 square miles. The Muddy Run Reservoir portion of the Project area is located 

entirely within Lancaster County, Pennsylvania. The Muddy Run Project Powerhouse and Upper 

Reservoir (Muddy Run Reservoir portion of the Project area) are located in Martic and Drumore 

Townships, Lancaster County, Pennsylvania, along the eastern shoreline of Conowingo Pond, 

approximately two miles downstream of PPL’s Holtwood Hydroelectric Project. 

The primary transmission line corridor portion of the Muddy Run Project APE is located in Lancaster 

County and in Lower Chanceford and Peach Bottom Townships in York County, extending 

approximately 4.25 miles from the Muddy Run Powerhouse on eastern bank of the Susquehanna River in 

Lancaster County, across the Conowingo Pond, to the PBAPS North Substation located in York County, 

Pennsylvania. 

Prehistoric and Historic Background 

The prehistoric cultural stages represented in the region include the Paleoindian Stage (ca. 12,000-7,500 

B.P.), the Archaic Stage (ca. 7,500-1,800 B.P.), and the Late Prehistoric Stage (ca. A.D. 150-1540). 

These are followed by the Protohistoric Period (ca. A.D. 1540-1860) and the Historic Period (ca. 1860- 

1950). The stages in this scheme are marked by a gradual development of Native American culture from 

its earliest beginnings to the peak of its development in the form of horticultural societies living in semi- 

permanent villages. The succeeding protohistoric period was a time of transition; Native American culture 

in the region was radically altered before being assimilated into the dominant European culture. 

Paleoindian Period (10,000 B.C.- 7,500 B.C.). The Paleoindian period is the earliest recognized period 

of human occupation in the area and includes three sub-phases: 1) Clovis, 2) mid-Paleo, and 3) Dalton. 

Paleoindian settlement patterns may be described as semi-nomadic within a well-defined territory. The 

subsistence focus was on hunting both large and small game and it is assumed that wild plants were 

exploited for food, textiles, and other purposes. Pleistocene megafauna, such as mammoth and mastodon, 

were mostly extinct by this time, so the emphasis in hunting was most likely toward deer, elk, and 

perhaps woodland caribou. 

Paleoindian groups throughout the Northeast and Middle Atlantic region are noted for their preference for 

high-quality lithic materials such as Delaware chalcedony, Flint Run jasper, Normanskill chert, and in 

Delaware, Custer (1984) describes the Delaware Chalcedony Complex where quarry related sites were 

systematically exploited. A settlement pattern focused on utilizing the resources of interior swamps, 

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headwaters areas and other resource-rich early Holocene habitats within a quarry-based settlement system 

seems to be characteristic of the Paleoindian period. 

Paleoindian peoples were hunters and foragers who depended, at least partially, on species of game which 

are now extinct in the region. Game such as mastodon, mammoth, caribou and elk along with deer and 

smaller game were hunted with thrusting spears tipped with fluted spear points. Such point forms are very 

similar in style throughout North America. 

The Paleoindian period in York and Lancaster Counties, as well as in adjacent areas of Maryland along 

the Susquehanna River, is sparsely represented, evidenced almost entirely by isolated projectile point 

finds (e.g., Paul Cresthull collection, Harford County, Maryland). The surface finds of Paleoindian 

projectile points have been recovered from various environmental settings, however, the majority (surface 

finds in private collections) were found close to high order streams as well as from islands in the 

Susquehanna River. It should be noted that in some of these collections, non-diagnostic Paleoindian 

scrapers are recorded in the site files as evidence of Paleoindian occupations (e.g., 36AD16). Collections 

from the lower Susquehanna River region show numerous fluted point finds manufactured from a great 

variety of cherts. These finds are mainly from river terraces, now inundated by rising sea levels in 

Chesapeake Bay during the Holocene (See Gardner and Wall 1978). 

Archaic Period (7500 B.C. - 1000 B.C.). The settlement data from Archaic sites show that during the 

Archaic period a significant increase in aboriginal populations occurred. It is apparent that regional 

settlement systems during the earlier part of the Archaic period largely reflect post-glacial adaptations. 

Though data from excavated Early Archaic sites is rare, these sites tend to reflect many trends seen in 

previous Paleoindian period manifestations (Carr 1998:63). There is still a major focus on the use of 

selected crypto-crystalline materials such as jasper, however, a greater variety of raw materials were 

exploited than in Paleoindian times. Resident populations were organized into small bands exploiting 

their surroundings in a restricted wandering pattern; that is, hunting and foraging trips stemmed from base 

camps located near critically important resources. These settlement data show sites in upland areas 

surrounding the Susquehanna River as well as along the floodplains and terraces of the river itself. Many 

of the sites known for this area are from riverine settings though slightly less than Paleo-Indian sites in 

the Susquehanna drainage (Carr 1998:58). It is expected that, during the Early Archaic period, base camps 

in the region would have been associated with sources of high quality crypto-crystalline materials such as 

jasper and cherts as well as within areas of maximum habitat overlap such as floodplain and high terrace 

areas. 

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Middle Archaic occupations represent significant changes in Early Holocene adaptations in the region 

that involve exploitation of a wider range of environmental zones and new additions to tool assemblages 

such as drills and, later, ground stone tools. There is also a higher frequency of these sites compared to the 

Early Archaic, and trend which perhaps started with the Kirk Phase of the Early Archaic. Sites producing 

Kirk points (e.g., 36YO288) appear to be more numerous than other sub-phases of the Early Archaic. 

Surface sites containing Morrow Mountain and bifurcate-based projectile points have been recorded in 

both upland and riverine settings. 

The Late Archaic period in this part of the Lower Susquehanna Valley ranges from about 3000 to 1000 

BC. Assemblages typically contain scrapers and drills (often fashioned from resharpened points), adzes, 

celts, netsinkers, anvil stones, and steatite bowls. The appearance of ground stone tools, utilized for the 

processing of gathered wild plant foods, evidences a reliance on new technology related to shifts in 

subsistence practices. Southeast of the Project area, in Harford County, Maryland, several substantial 

soapstone quarries have been recorded (18HA91 and 18HA92) containing fragments of several dozen 

stone bowls in various stages of manufacture and associated with surface finds of Orient fishtail and 

broadspear points. These quarries show evidence of aboriginal quarry pits dug to obtain the high quality 

serpentine common in the area. 

Settlement patterns in the region during the Late Archaic show an increased use of all ranges of upland 

environmental settings. Surface site data show an increase in site size as well and, at the same time, more 

ephemeral types of environments were being exploited than before. Overall, Late Archaic subsistence 

covered a broad spectrum of upland resources with the exploitation of acorns, hickory nuts, and butternuts 

as well as seasonally abundant game, large and small. In York and Lancaster Counties, site distribution 

data show a tremendous increase in numbers of sites in a much wider range of environmental settings 

such as upland swamps (e.g. 36YO269, 270, and 280). Fishing appears to have assumed greater 

importance over previous times, as many of the sites located in the region are floodplain and island 

occupations which were probably seasonal fishing stations. These sites consistently yield netsinkers and 

related fishing equipment. Some base camp sites are located near smaller streams and rivers, and these 

perhaps are also fishing camps. 

Woodland Period (1000 B.C. - A.D. 1600). The Woodland period is marked by the development of 

settled village horticulture, the growth and development of widespread burial ceremonialism marked by 

mound construction, and the introduction of ceramics into the material culture. A full-blown elaboration 

of the burial ceremonialism concept is evidenced by Adena mound complexes. Mound building had been 

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initiated during the previous Late Archaic period, but on a smaller scale with the construction of simple 

stone mounds or burials on natural hilltop features. Some of these developments diffused into the lower 

Susquehanna and Chesapeake Bay area, but the evidence is limited chiefly to surface finds of trade items 

(e.g., Adena blocked-end tubular pipes, hematite hemispheres, and gorgets) along major streams and 

occasional finds of Adena projectile points. The mounds which typify the burial ceremonialism of this 

period in other regions do not appear to be represented here but they do occur further upstream, 

tentatively associated with the Clemson Island culture (Turnbaugh 1977). 

During the Early Woodland period (1000 - 300 BC), regional trade networks became more established. 

Early Woodland sites are generally larger than sites of previous times, and there seems to be an increasing 

reliance on riverine and estuarine resource areas. Cultigens were gradually introduced but never assumed 

great importance in Early Woodland subsistence economies. Stable wild plant resources along with 

hunting and fishing continued to support human populations in the region. More sedentary communities 

were established, particularly in the rich and ecologically diverse riverine settings, although tightly 

patterned mobility still characterized the settlement patterns of these Early Woodland period societies. In 

general, adaptive strategies were geared to exploiting a more limited and predictable array of stable 

resources within a smaller territory than in earlier times. The region’s critical resources, such as the 

soapstone quarries near the mouth of the Susquehanna River, were an essential part of these settlement 

patterns. 

Surface sites dating to the Early and Middle Woodland periods in the lower Susquehanna Valley area are 

marked primarily by surface finds of Fishtail and Jacks Reef projectile points. Some evidence of Early 

Woodland occupations has been recovered from buried surfaces on islands in the Lower Susquehanna, 

such as those described above for the Late Archaic period. Many of the Fishtail points are manufactured 

from meta-rhyolite, marking the continued preferential use of this raw material. Continuity also is evident 

in the tools found in Early Woodland assemblages that differ little from their Late Archaic predecessors. 

Intensification in trade networks over a large region is one of the notable trends evident by the onset of 

the Middle Woodland period (300 B.C. to A.D. 900). There is also an intensification of horticultural 

practices, although hunting, fishing, and plant collecting are still primary subsistence pursuits. The 

subsistence economy is also marked by the initiation of maize horticulture. The large number of sites for 

this time period and the extensive size of some of the sites support the argument for seasonal aggregation 

and dispersal. Tool kits utilized by Middle Woodland peoples are basically the same as those used during 

the succeeding Late Woodland but more exotic and high quality lithic raw materials are evident in Middle 

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Woodland assemblages. The technology evident in many of the Middle Woodland sites seems to favor 

bifacial tool production rather than a prepared core and blade flake technology as would be found in the 

Ohio Valley and adjacent regions at this time. 

Late Woodland and protohistoric occupations in the Lower Susquehanna River Valley are found 

primarily on the floodplains, especially the large villages which are found on levees and adjacent to small 

tributary streams (Raber 1993). These are primarily horticulturally based villages which evidence the use 

of maize, beans, squash, and eastern agricultural complex plants. Also found throughout the region are the 

small base camps and procurement sites. By circa AD 1300, maize agriculture is well established and 

many settlements show evidence of fortification. Many of the sites in the region that contain Late 

Woodland artifacts are multi-component surface sites in high order stream locations. 

Other trends in the Late Woodland period include shifts in lithic raw material preferences. These shifts 

may relate to the development of more sedentary lifestyles, the increasing reliance on horticultural 

products and a concomitant de-emphasis on intensive hunting and gathering. The result would have been 

smaller foraging and hunting ranges, which would, in turn, have resulted in more limited exploration for 

lithic raw materials and greater dependence on near-camp resources as well as those easily obtained 

through trade. Gradual movement of Susquehannock peoples into the Lower Susquehanna region from 

the Upper Susquehanna can be seen in a succession of archeological sites with the earliest dating to the 

mid-1500s (Turnbaugh 1977:238). Susquehannock sites include burials with grave offerings of historic 

items, usually interred just outside of the village, and clusters of rectangular houses surrounded by a 

palisade. Subsistence pursuits include cultivation of corn, beans, squash, and eastern agricultural complex 

cultigens, supplemented by hunting and fishing. By 1675, the end of Susquehannock occupation in the 

region was completed as a result of warfare and disease (Kent 1993). 

Colonial Period: Early European Settlement (1620-1775). The earliest European exploration of the 

Susquehanna River is attributed to John Smith, who sailed into the mouth of the Susquehanna River in 

1608 though earlier visits by Spanish Jesuits in the late 1500s are also described in early explorer's 

accounts. In the early 1600s Edward Palmer established a fur trade post on an island at the head of the 

Chesapeake Bay now called Garrett Island (Preston 1901; Wright 1967), in Cecil County. Early economic 

pursuits in the region during the 1600s and the first part of the 1700s were based primarily on tobacco 

cultivation which was transported overland from tobacco plantations to Bay access points via rolling 

roads. Shipping points were located on the Gunpowder River and the Bush River, the latter an early 

settlement area of the late 1600s. 

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Land at the mouth of the Susquehanna River was cleared for tobacco plantations in the second half of the 

seventeenth century. Settlement in the Project area in southern York County, Pennsylvania an area known 

as "The Barrens”, was settled by Scottish and Irish families (Hershner 1977) as well as Catholics from 

Maryland (Fortenbaugh 1950; Rupp 1845; Gibson1886). These early settlements were primarily 

agricultural with some residents providing services such as blacksmiths, wheelwrights and other 

supporting enterprises. The economy at that time was focused on wheat production and as wheat farming 

became more profitable, mills emerged along with additional supportive trades. 

By 1709 Mennonites were taking advantage of the rich agricultural lands in Lancaster County, 

Pennsylvania and were soon followed by the Huguenot families, Scottish, Scotch Irish, English, Swiss, 

Quaker, Irish and Palatine (Wood 1979). The population was diversified both in terms of ethnic 

background as well as job skills and religions which included Mennonites, Methodists, Anabaptists, 

Presbyterians, United Brethren and others such as Catholics and Jews. Lancaster County was established 

in 1729 as an extension of Chester County, from which many of the settlers originated. At the time it was 

first settled, this was considered Pennsylvania’s western frontier and the settlements were primarily small 

farms with political leadership being dominated by landed and professional people (Loose 1976). 

By the mid-eighteenth century, single-owner proprietorships were the most common. Fur traders on the 

frontier exchanged raw materials for manufactured goods in Lancaster. As the frontier moved westward, 

other towns including Shippensburg, Carlisle, and York assumed principal trading responsibilities while 

local business concentrated on processing and manufacturing. In 1749 York County was formed from 

Lancaster County. 

Settlers suffered from repeated Indian raids during the French and Indian War. The threat of such raids 

resulted in a system of frontier fortifications and trade supervision. The French and Indian War 

stimulated the local economy and as hostilities increased, Lancaster became a military center, as well as 

manufacturing and supply station. Shopkeepers received commissions to supply troops involved in 

placating the frontier, and military officials requested the services of artisans to provide them with 

manufactured goods. Local gunsmiths manufactured thousands of guns used during the Revolution and 

several salt works were set up to manufacture saltpeter. 

The development of many of the settlements and villages surrounding the Project relate directly to the 

proximity to the Susquehanna River and its tributaries and creeks. As these areas developed, the need for 

various modes of transportation grew as well. The use of roads, ferries, bridges, and canals allowed 

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residents and businesses to transport their goods and travel throughout the region. Roads often served as 

the earliest and simplest transportation routes. The first post road from Alexandria, Virginia to 

Philadelphia ran through Harford County, Maryland, located south of the Project, by 1670. The road 

followed the first settlements along the coastal areas, and was essential in providing early landowners 

with a crude highway for their travel to the early government seats. By 1687, a second post road was laid 

out and was noted as a more direct north-south route. It was known as the “path that runs from the 

Potomack to the Susquehanna” and the “King’s Road” (Wright 1967:102–103). 

Crossing the Susquehanna was often accomplished by ferry in the early periods. Holtwood village in 

Lancaster County is located near the site of an early ferry that crossed the Susquehanna. William H. 

Nelson started the ferry service in 1738, and it was transferred to James McCall in 1806. The well-used 

ferry, later renamed Clark’s ferry, continued throughout the nineteenth century, and was closed around 

1936 (Snyder and Boyle 1984c). 

The American Revolution (1775-1783). In Pennsylvania, York served as an interim capital for the 

Continental Congress during a short period, and York County served as a cross-roads for armies moving 

south during the latter part of the Revolution. Lancaster was also, for a short period, the country’s capital 

during the Revolution and later, the state capital (1799-1812). The role of Lancaster during the revolution 

was as a producer of both durable goods and food for the war effort (Kessler 1975; Loose 1976). After the 

Revolution, westward expansion continued and Lancaster assumed a much less prominent role in the 

region’s economy. In spite of this, local industries such as grist- and sawmills, lime kilns, textile 

industries and craft specialists continued to thrive. The town and county of Lancaster grew quickly in the 

late eighteenth century and became the residence of a number of wealthy landowners and prominent 

craftsmen such as iron workers and glass makers such as Henry Stiegel and Robert Coleman. 

Before and after the Revolution, there were efforts to utilize land resources, especially in the production 

of iron. The tradesmen profited from army provisioning contracts; skilled artisans such as metalworkers, 

shoemakers, tanners, and woodcraftsmen were commissioned to manufacture boots, saddles, casks, 

barrels, etc. and local gunsmiths manufactured thousands of guns used during the revolution and several 

salt works were set up to manufacture saltpeter. 

The processing of metal was an important part of both Lancaster and York County’s early economy. 

From the middle of the eighteenth century through to the middle of the nineteenth century, Martic Forge, 

on Pequea Creek (roughly six miles above the Project) in Lancaster County, Pennsylvania, was the 

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industrial center of Martic Township (Clare 1892:1). Here, too, iron production was the industrial focus 

for this area early on, and it was also one of the more important iron-producing centers for Lancaster 

County. 

The Federal and Antebellum Periods (1783-1840). Castle Fin Forge, located in the southern portion of 

Lower Chanceford Township on Muddy Creek, opened in 1810 and was also known as Palmyra Forge 

(Sheets 1991:56). Lower Chanceford Township was also the home of York Furnace, which was located 

on Otter Creek and was in operation from 1830 to 1875. Sometimes called “Speck,” the furnace produced 

cannons during the Civil War (Sheets 1981). By the end of the nineteenth century, Lancaster County 

furnaces and forges on the Conowingo and Octoraro Creeks were no longer running (Clare 1892). 

On the western side of the river, in spite of concerted efforts, early settlers in the Peach Bottom area of 

York County did not have much luck with growing rye or wheat. These crops, as well as barley, grew 

better in other parts of York County (Sheets 1981). The abundance of rye and corn in the surrounding 

area did, however, give rise to the production and sale of whiskey in York County. In fact, from 1800– 

1830, the county led all of Pennsylvania in whiskey production (Sheets 1981). 

The advent of canals was significant for the shipping industry. In the nineteenth century, canals and later 

railroads connected inland cities to those on the coast, fostered western expansion, and encouraged greater 

industrial production by facilitating transportation of more goods and raw materials. Large amounts of 

coal and lumber were transported on canals in the nineteenth century. 

The Susquehanna Canal, also known as the Maryland, Port Deposit, and Conowingo Canal, was opened 

to traffic in 1803 and was located on the east bank of the Susquehanna. It ran from the Pennsylvania- 

Maryland border south to the outskirts of Port Deposit. It is noted as contributing greatly to the growth of 

towns in along the Susquehanna, including Port Deposit (MHT, NHRP Detail Report, Port Deposit 

Historic District, CE-1291). The canal included nine locks. In spite of the corporation holding exclusive 

rights to the canal and any gristmills or water works built upon it, it was not financially successful 

(Wilner 1984:5). It was bypassed frequently on the river heading downstream, so not enough tolls were 

collected to maintain it properly. The canal was sold at auction in 1817 and was abandoned when the 

Susquehanna and Tidewater canal opened in 1840 (Shank 1988). 

The Susquehanna and Tidewater Canal was the most significant canal for the area with a charter that was 

approved on April 18, 1835 by the Pennsylvania and Maryland legislatures. Open by 1840, it was located 

on the west bank of the river and went as far as Wrightsville on the west side of the Susquehanna in York 

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County, terminating in Havre De Grace in Harford County (Smeltzer 1963). Most of the traffic on this 

canal was going to Baltimore, Philadelphia, and New York (Smeltzer 1963). There was a two-tiered 

towpath built on the canal; the mules on the lower walkway went east and the mules on the upper 

walkway traveled west (Smeltzer 1963). 

Railroad transportation made an early appearance in the Lower Susquehanna Valley because of its 

location on a natural travel corridor between the South and the Middle Atlantic states. Railroad investors 

were also eager to tap the natural resources, especially anthracite coal. Initially, canals had the advantage 

of capacity and cost. Before long, however, improvements in locomotives allowed trains to pull greater 

loads. Canals could not operate in the winter months and they were vulnerable to ice and flood damage. 

As canal revenues slipped after the Civil War, high maintenance costs became an increasing drain on 

profits. Inevitably, canals came under the control of railroad companies. Some canals became more 

valuable as rights-of-way for new rail lines or highways (Stranahan 1993). Planned in 1828 and finished 

in 1834, the "Iron Rail Road" was built from Philadelphia to Columbia on the Susquehanna River and 

included a stop in Lancaster. It was the first publicly-built railroad in the world. In 1837, the 

Philadelphia, Wilmington, and Baltimore line reached the Susquehanna. In 1857, local interests 

incorporated the Columbia and Port Deposit Railroad in Pennsylvania as the Washington and Maryland 

Line Railroad Company. The name was changed to the Columbia and Port Deposit Railroad in 1864. Its 

nickname was “The Port Road.” Construction was begun in 1866. Part of the line was in operation by 

1874, but the work on constructing the remainder progressed slowly. The entire 40-mile line was put into 

operation in July 1877. 

With the advent of the railroad, the counties within the Project area began to change rapidly. Abundant 

natural resources allowed the area to continue to grow and prosper. Fisheries, agricultural products, large 

forested areas, and Cecil and York Counties’ rich wealth of mineral resources, such as chrome, granite, 

magnesium, and iron ore placed the Lower Susquehanna Region at the heart of America's early 

manufacturing and extractive industries. 

As transportation facilities improved during the nineteenth century—in the form of canals and railroads— 

numerous industries were able to flourish in the Lower Susquehanna Valley, including tanbark mills, 

paper mills, fulling mills, sawmills, flint mills, lime kilns, canneries, creameries, and ice harvesting 

(Sarudy 2001). Mining and quarrying became the economic mainstays of Peach Bottom Township. 

Although abandoned by 1895, chrome mining at Rock Spring and Epsom salt mining had been notable 

industries in the township. 

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The Civil War (1861-1865). During the Civil War, Confederate troops under Generals Gordon and 

Early entered York for a brief period in June 1863 just prior to the battle of Gettysburg. Also in June, 

General Ewell’s corps of Confederate raiders, coming from Carlisle, entered Dillsburg under the 

command of Colonel Jenkins. They camped about 1/4 mile south of town before moving on. Other than 

this, very few events directly related to battles and troop movements occurred in the area. During the 

Civil War little military activity occurred in Lancaster County with the exception of troop movements and 

support facilities before, during and after the battle of Gettysburg. 

Post-Civil War and Industrial Expansion (1865-1900). After the Civil War, farming resumed its 

importance as the primary commercial enterprise in the county. Smaller industries developed as well in 

this largely rural county. Industrial expansion accelerated along with the growth of transportation 

networks designed to more efficiently export products of the local economy. Railroad construction 

increased in the late 19th century to the early 20th century. 

The Peach Bottom Railway was chartered in 1868 to build a narrow-gauge rail line from Philadelphia to 

haul coal from the Broad Top coalfields in southern Pennsylvania. The Eastern Division was supposed to 

connect Philadelphia with the Susquehanna River at Peach Bottom. Instead, only a line from Peach 

Bottom to Oxford was completed in 1878. The Middle Division was built between Delta (in the slate belt) 

and York in 1876. No money was available to build the bridge over the Susquehanna that would unite the 

divisions. The Eastern Division was reorganized into the Peach Bottom Railroad in 1881 (later the 

Lancaster Oxford & Southern Railroad) and the Middle Division into the York and Peach Bottom 

Railway. The York and Peach Bottom Railway reached Peach Bottom in 1883. The Maryland Central 

Railroad built a line between Baltimore and Delta. After acquiring the York and Peach Bottom Railroad, 

they both became part of the Maryland and Pennsylvania Railroad Company (the Ma & Pa). The line was 

abandoned south of York in 1985 (Maryland and Pennsylvania Railroad Historical Society 2007). 

The rains associated with the Johnstown Flood, or the great storm of 1889, had a large impact on the 

Susquehanna and Tidewater Canal in the Project area. By May 31, the west branch of the Susquehanna 

was filled with logs and began to rise. Homes, mills, lumber, and crops were carried down the river in the 

flood. The flood dealt a huge blow to the canal, destroying miles of the canal, marking the beginning of 

the end (Smeltzer 1963). The canal was bought by the Reading Railroad by the 1890s and closed by 

1900. 

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The Modern Era (1900 to Present). In the early twentieth century, creameries were a significant 

element of Lancaster’s agricultural economy. In 1916 there were 40 creameries in the county. One of the 

biggest, Farmer’s Creamery, was located in Drumore Township (Roddy 1916). Agricultural land use 

continued into the twentieth century; in 1960, Lancaster County was the largest farming county in 

Pennsylvania with 4,650 farms (Stevens 1964). In comparison, York County had 2,700 farms, a little 

more than half of those in Lancaster County (Stevens 1964). 

The Columbia & Port Deposit Railroad was the principal route for moving freight between points on the 

Pennsylvania Main Line and points on the Philadelphia, Baltimore, and Washington line. Freight trains 

were more efficiently and economically operated through the low grade of the Lower Susquehanna Valley 

rather than the heavier grades used for through passenger service (Burgess and Kennedy 1949). The 

Columbia & Port Deposit Railroad was relocated to higher ground from Conestoga Creek Bridge to Safe 

Harbor in 1905–1906 because of construction of the Holtwood Dam and the resulting lake. 

In 1916, the Columbia & Port Deposit Railroad and other lines consolidated into the Philadelphia, 

Baltimore, & Washington Railroad Company, a subsidiary of the Pennsylvania Railroad Company 

(Burgess and Kennedy 1949:375–376; 554). The railroad was relocated between Port Deposit and Fite’s 

Eddy in 1926–1928, when Conowingo Dam was built. The railroad was electrified in 1938 and then de- 

electrified in the early 1980s. It is still in active service today and owned by the Norfolk Southern 

Corporation (Smith 1997; Trower 2002). 

Hydroelectric power production facilities were developed beginning in the early 1900s to take advantage 

of the Susquehanna River’s force. In 1904, the York Haven Hydroelectric Station, located at Conewago 

Falls, was opened. The Holtwood Power Plant, which began operation in 1910, was the largest 

hydroelectric facility on the Susquehanna River, and is a major producer of electricity for south central 

Pennsylvania (Synder and Boyle 1984). By 1916, there were nine hydroelectric plants in Lancaster 

County (Roddy 1916). The Conowingo Dam was built near Darlington, Maryland a short distance 

downstream of the Project between 1926 and 1928 to provide hydroelectric power to supply Philadelphia 

and southeastern Pennsylvania with electricity. (Lower Susquehanna Heritage Greenway 2006; MHT 

Determination of Eligibility (DOE) Form, US 1 over Susquehanna River/Conowingo Dam, HA-1971). 

Electricity from the plant also powered railroad lines between New York and Washington, D.C., and was 

used for industrial and residential applications. When constructed, Conowingo Dam was the second 

largest hydroelectric development in the United Sates after Niagara Falls (Camden County Vocationalite, 

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June 1930). It was and still is the single largest generation station to be built in one step, and used the 

most up-to-date technology, as well as the largest turbines and generators ever produced (Exelon 2007). 

On September 21, 1964, FERC granted PECO a license to construct the Muddy Run Project, a pumped 

storage hydroelectric facility located in Lancaster and York counties, Pennsylvania. Construction 

commenced that year and commercial operation began in 1967. When completed, the Muddy Run Project 

was the largest pumped-storage facility in the world. 

Prehistoric and Historic Archeological Resources 

Exelon conducted archaeological field surveys to identify cultural resources between 2010 and 2011. The 

survey of the APE combined verification of data from the earlier surveys and systematic field 

investigations of locations not previously surveyed. All areas within the APE were included in the field 

survey, where safety considerations allowed for it. The results of the survey are summarized below. 

Two Areas of Interest (AOI) were identified during the Phase IA to have a high potential for 

archaeological deposits based on topographic landform and hydrological association. No prehistoric 

archaeological sites have been recorded on or around the Muddy Run Reservoir shoreline. Because the 

reservoir is a drowned stream valley, landforms surrounding the reservoir shoreline consist of former 

upland flats or ridges. What were once feeder tributaries into the Muddy Run valley now consist of water- 

filled valleys that contain submerged tributary terraces, floodplains, and stream confluences. Such 

landforms, now-submerged, are typically considered to have High Probability for archaeological 

resources while surrounding uplands are generally considered to have lower site probability with the 

exception of certain landforms such as prominent ridge tops overlooking stream valleys. 

Prehistoric archaeological sites were, therefore, expected to occur on all level landforms along the 

shorelines suitable for human habitation and/or occupation where colluvial or alluvial soil deposition may 

have preserved these sites. In particular, drowned stream confluences and associated terraces were 

considered to have a High Probability for site occurrence as such areas represented important destinations 

and intraregional communication links during prehistory. 

A Phase IB archaeological survey of the two AOI within the Area of Potential Effect (APE) was 

conducted in 2010. In total, 19 shovel test pits were excavated at intervals of 15 meters within five 

meters of the shoreline of the reservoir. No artifacts or cultural features were discovered as a result of the 

survey, and no further investigation of AOIs 1 and 9 is recommended. 

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Historic Period Buildings and Structures 

Exelon conducted an architectural survey and assessment within the APE of the Muddy Run Project 

(Project). The purpose of the architectural survey was to identify and map any NRHP-listed, NRHP- 

eligible, and previously surveyed architectural resources within the Project APE. 

The survey concluded that within the Project APE, there are no NRHP-listed architectural resources or 

architectural resources determined NRHP-eligible by the PHMC. To date, there has been no 

comprehensive architectural survey conducted within the Project APE or its immediate vicinity. There is 

one previously identified resource within the Project APE, the Ritchie Robinson House in Peach Bottom 

Township. This resource was evaluated by the PHMC in 2001 and determined ineligible for NRHP- 

listing. However, the PHMC typically re-evaluates NRHP evaluations conducted over five years prior to a 

current survey. 

The completion of this architectural survey and assessment has resulted in the recommendation that the 

previously identified resource within the APE, the Ritchie-Robinson House, located at the southern end of 

the Project transmission line, is not recommended eligible for the NRHP either individually or as part of 

any potential rural historic district. The farm does not possess a strong representation of a range of 

typical buildings and landscape features that illustrate important changes over time in the region’s 

agricultural history. The survey and assessment has identified no other architectural resources 50 years or 

older in the APE. 

The Phase IA archaeological investigation integrated a review of historical documents, local histories, and 

cultural resource site files along with field reconnaissance of the Project shorelines. Background research 

for the Project was conducted in October 2010 at the PHMC in Harrisburg, Pennsylvania. An 

archaeological shoreline reconnaissance was completed in November, 2010. 

Historical background and cartographic research has shown that the early history of the general Project 

region was marked by agriculture, iron forging, quarrying, and milling and this trend continued into the 

mid-nineteenth century when tourism began to take an active role. The development of many of the 

settlements and villages surrounding the Project area relate directly to the proximity to the Susquehanna 

River and its tributaries. 

Research at the PHMC indicated that no NRHP-listed historic resources are located within the Project 

area and that previous archaeological investigations in the vicinity have been rather limited. Most of the 

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studies have been in the uplands surrounding the Susquehanna River and its tributaries. Investigations 

that have been undertaken along the periphery of the Susquehanna River have been limited in scope or 

have been conducted by amateur collectors. Background research showed that avocational work has been 

conducted on several of the Susquehanna islands. This includes research in the 1950s on Bear Island 

(Kinsey 1959) and more recent research on Piney Island (Kent 1996). 

Site file research at the PHMC depicted 3 previously recorded archaeological sites within the Project APE 

and an additional 22 sites within a one-mile radius. Of the 25 total sites within or in the vicinity of the 

Project area, a majority are located on the Conowingo Island Group in close proximity to the Muddy Run 

Project. 

Archaeological field reconnaissance of the shorelines of the Muddy Run Power Reservoir identified two 

areas of high localized erosion corresponding to areas of high site probability. Other areas of high site 

probability exhibit low erosion. 

Exelon conducted a Phase I architectural survey and assessment within the Project APE. The purpose of 

such investigations would be to determine whether any NRHP-eligible sites are being impacted by 

shoreline erosion and to provide resource management recommendations. The purpose of the Phase I 

survey was to identify and map any NRHP-listed, NRHP-eligible, and previously surveyed architectural 

resources within the Project APE. The Phase I Survey consisted of definition of the Project APE, 

background research on previously identified architectural resources in the APE, preparation of an 

historic context, and a field reconnaissance of the APE. Based on background research, there are no 

NRHP-listed architectural resources or architectural resources determined NRHP-eligible by the PHMC. 

There is one previously identified resource within the APE, the Ritchie-Robinson House (PHMC ID# 

118594) located at the southern end of the Project transmission line. It was recommended that the existing 

survey information on the Ritchie-Robinson House and its evaluation for NRHP eligibility. Based on the 

field reconnaissance there are no other architectural resources 50 years or older located within the Project 

APE. 


Continued operation of the Project will not affect historic properties listed in or eligible for inclusion in 

the NRHP. Exelon’s relicensing studies determined that no Project facilities are eligible for inclusion in 

the NRHP. Continued Project operations and maintenance and associated Project recreation has a 

potential to affect sites due to ground disturbing activities (e.g., erosion, trampling and blading). In some 

E-187



cases sites are being affected by siltation, which may be considered a positive effect because it provides 

site protection. Therefore, Exelon’s proposed alternative includes as a proposed PM&E a license article 

which requires consultation prior to any land disturbance activity associated with the ongoing operation of 

the Project. 


Exelon’s proposed alternative includes a proposed license article that requires Exelon to consult with the 

Pennsylvania SHPO prior to any land-clearing or land-disturbing activities within the Project boundaries, 

including recreation developments at the Project. If Exelon discovers previously unidentified 

archeological or historic properties during the course of constructing or developing Project works or other 

facilities at the Project, Exelon shall stop all land-clearing and land-disturbing activities in the vicinity of 

the properties and consult with the SHPO. 

In either instance, Exelon shall file for Commission approval a cultural resource management plan 

prepared by a qualified cultural resource specialist after having consulted with the SHPO. The plan shall 

include the following items: (1) a description of each discovered property indicating whether it is listed 

on or eligible to be listed on the National Register of Historic Places; (2) a description of the potential 

effect on each discovered property; (3) proposed measures for avoiding or mitigating effects; (4) 

documentation of the nature and extent of consultation; and (5) a schedule for mitigating effects and 

conducting additional studies. 


No additional unavoidable adverse effects are anticipated. 

E-188

Aesthetics 



3.3.9. Aesthetic and Noise Resources 


The Muddy Run Project lands include many areas of high aesthetic value due to their topography, 

geology, and vegetation. The landscape surrounding the Muddy Run Reservoir reflects the agricultural 

economy that has historically dominated the area. The rolling landscape consists of small farmsteads, 

many of which were settled by Amish families and colonists from other religious sects. Single-family 

homes and scattered low-density residential developments are located among these farms. Tiny villages 

that have grown up around the busiest intersections provide the farm community with basic goods and 

services. Clustered around these village centers are a handful of industrial sites including feed and grain 

mills, rock quarries and produce packaging plants. Woodland and open space areas commonly exist along 

the major stream valleys where steep slopes and poor soils discourage land development. 

The facilities and features of the Project are located adjacent to the Susquehanna River in southern 

Lancaster and York counties, Pennsylvania. The Piedmont Province Upland Section gives the 

Conowingo Pond its unique landform. The rivers and streams in the province carved the rolling 

topography to form narrow valleys, suitable for the construction of water reservoirs. This erosion of the 

land created the hillsides, averaging 300 feet in height above the water that provide a backdrop to the 

Project area. Stronger rock, more resistant to erosion, helped create the numerous islands that populate 

the pond. The geologic history is apparent throughout the Conowingo pond, with tributaries displaying 

glacial erosion of the past in their meanders, chasms, cliffs, and cascades. This history has created a 

unique vista, with steep slopes marking the transition between the flat narrow shoreline of the pond, and 

the rolling open space and farmland adjacent to the Project. 

The rich vegetation that lines the shoreline throughout the Project creates additionally aesthetic value to 

the area. Due to the steep slopes and rocky soils that surround the Conowingo Pond, the area has 

remained relatively untouched and in its native state. This lack of development has allowed the region to 

facilitate the growth of a wide variety of native plant communities, many of which are considered rare or 

threatened in the wild. The majority of the shoreline is heavily wooded, with primary natural plant 

communities of rich hemlock-mesic hardwood forest, dry oak-mixed hardwood or red oak-mixed 

hardwood forest, and Virginia pine-mixed hardwood forest. Several unusual and unique plants are found 

in these wooded areas, including Snow Trillium, Goldenseal, rhododendron, hemlock, mountain laurel, 

Umbrella Trees, and American Holly. 

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Perhaps the most impressive of the numerous aesthetic qualities in the Project area are the diverse wildlife 

populations within it. The bald eagle, which maintains a strong population in the Conowingo Pond and 

Lower Susquehanna River, can be enjoyed by even novice bird watchers. Lying along part of the Atlantic 

Flyway, numerous migratory bird species use the Conowingo Pond and Lower Susquehanna River as a 

resting spot. Some species known to nest in the area include Osprey, black vulture, white-eyed vireo, 

scarlet tanager, prairie warbler, screech owl, herring gull, and red-tailed hawk. In addition to the avian 

wildlife, the forested areas provide habitats for mammals such as red and grey fox, raccoon, red and grey 

squirrel, chipmunk, opossum, and white-tailed deer. Other mammals observed in the Project area include 

river otter and mink. The wide variety of wildlife creates an impressive aesthetic quality for those 

wishing to observe nature. 

Overall, the upper reservoir, powerhouse, recreation facilities, and other Project facilities tend to blend 

into the landscape from most viewpoints. However, the upper reservoir and dam is clearly a man-made 

feature on the landscape. The powerhouse also exhibits a visual contrast due to its location on 

Conowingo Pond, light colors, uniform textures, and geometric shapes seen from vantage points within 

the river valley. The presence of the transmission corridor also creates a visual contrast to the existing 

land uses and aesthetics. The 4.25 mile long transmission corridor is also a noticeable feature of the 

landscape with the transmission poles, lines, and vegetation management related modifications visually 

present within and adjacent to the transmission line corridor. If the recreational users find the visual 

contrast of the powerhouse objectionable, there are other parts of Conowingo Pond with less contrast 

available for use (Exelon 2011m). 

Located immediately adjacent to Project lands, Susquehannock State Park is a 224-acre park on a wooded 

plateau overlooking the Susquehanna River in Drumore, Pennsylvania. Among the park’s primary 

attractions are river overlooks, which afford panoramic views of the lower reaches of the Susquehanna 

River. Hawk Point, the park’s main overlook, provides a spectacular view of the upper reaches of 

Conowingo Pond. The Conowingo Islands are in view from Hawk Point including Mt. Johnson Island, 

the world’s first bald eagle sanctuary. Also located at the park is Wissler’s Run Overlook, which gives an 

excellent view of the original rocky nature of the Susquehanna River’s natural riverbed with the well- 

known Norman Wood Bridge (Route 372) in the background. 

To better characterize the existing visual setting; in 2010 Exelon conducted a visual quality assessment of 

the Project’s facilities (Exelon 2011m). To evaluate the potential visual impact of Project operations, 

photographs were taken to document the existing visual condition and visibility of Project facilities from 

E-191



the key viewpoints in the view shed of the Project. In general, the location at each site chosen as the 

viewpoint represents typical views experienced by visitors. Photographs were taken during the spring, 

summer, fall, and winter seasons in both daylight and darkness. Daytime representative views included a 

view toward the powerhouse, using both wide angle and telephoto zoom, as well as views in the three 

other directions. Other views may have been included as well. During the night, generally only one 

photograph was taken toward the powerhouse to assess the aesthetic effects of lighting for Project 

operations, unless significant light features were present in other directions as well. 

Noise 

To evaluate the potential audio impact of Project operations, the ambient noise level was measured at ten 

sites in the vicinity of the Project. The assessment was performed in both daylight and darkness during 

each of the four seasons of 2010—spring, summer, fall, and winter—for a total of eight recordings per 

site (Figure 3.3.9-1). The results from the audio assessment at the ten sites are presented as values which 

represent average baseline conditions at each site for each sampling event. Table 3.3.9-1 presents the 

results for each sampling event, and also provides average, minimum, and maximum readings for each 

site and for all sites at each sampling event (GSE and Normandeau Associates 2012b). Additionally, 

readings which are shaded green in this Table indicate that the Muddy Run Project was not in operation 

during the time the monitoring was performed. 

Existing ambient baseline sound levels at the sites monitored in 2010 ranged from 34 to 61 decibels 

(dBA). Measured daytime sound levels for the sites varied from 37 to 55 dBA, while the average daytime 

sound level for the ten sites varied between 41 and 46 dBA. Measured evening sound levels varied from 

34 to 61 dBA, while the average evening sound level for the ten sites varied between 40 and 52 dBA 

(Exelon 2011). General patterns from the data reveal daytime dBA levels which were generally lower 

than evening dBA levels, and average dBA levels for both day and evening measurements for each site 

were lower as the distance to the Project facility increases. Finally, there appears to be no correlation in 

the data between increased dBA measurements corresponding to times when the facility was in operation 

(either pumping or generating) versus times the facility was not operating. 

The Cold Cabin Boat Launch (Site 8) is the only site for this study which is located in Peach Bottom 

Township. A maximum level of 54 dBA was recorded at this site, while the minimum level recorded was 

37 dBA. All sound levels recorded at this site were more than 10 dBA below the standard of 67 dBA 

established by the municipal ordinance for all non-agricultural uses in the Township. 

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The Visual Analysis Study performed for the Muddy Run Project confirmed that the Muddy Run 

powerhouse is clearly visible during both day and night at the three island sites as well as Wissler’s Run 

Park. At the Muddy Creek Boat Launch, Lock 15 Interpretive Area, and Susquehannock State Park, the 

powerhouse usually cannot be clearly seen during the day, but the glow of its lights is visible at night. 

Other facilities such as the transmission line towers on Lower Bear Island (day) and the intake towers 

lights (night) are generally visible at these sites. At Cold Cabin Boat Launch, no facilities can be seen 

during the day, and only the intake tower lights can be seen at night. At Muddy Run Wildlife 

Management Area, only the dam and Power Reservoir can be seen during the day, and a faint glow from 

the powerhouse and/or intake towers can sometimes be seen at night. Lastly, at Muddy Run Recreation 

Park, only the Power Reservoir can be seen during the day; no lights can be seen at night. 

The relative visual impacts of Muddy Run Project operations vary among monitored sites. The impact is 

highest at nighttime, and at sites with a clear line of sight to the powerhouse (i.e., Conowingo Islands, 

Wissler’s Run Park) and decreases with distance, obstructions, and foliage density. Qualitatively, four of 

the sites were found to have generally minimal or visual impact, two were found to have moderate 

impact, and four were found to have a relatively high impact. The impact of Project lighting at nighttime 

is highest at select locations (i.e., Conowingo Islands); however the Conowingo Islands have restrictions 

against public use at night, so any impacts to recreation is minor. In addition, the results from Muddy Run 

Study 3.11-Recreation Inventory and Needs Assessment and Conowingo RSP 3.26-Recreation Inventory 

and Needs Assessment did not indicate that the use and enjoyment of the recreation sites examined in this 

study are adversely affected by any visual and/or audio impacts. The impact of Project lighting at 

nighttime is highest at select locations (i.e., Conowingo Islands); however the Conowingo Islands have 

restrictions against public use at night, so any impacts to recreation is minor. 

Exelon’s proposed Project would have a minor effect on noise. The proposed Project is located in a rural 

area and data collected shows that the Project does not create levels of sound that will result in an effect 

from the Project. 


Exelon is not proposing any aesthetic or noise related measures. 

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Muddy Run operations will have a minor impact on visual and aesthetics. Construction of Exelon’s 

proposed recreation facility improvement will result in short-term increases in noise levels. However, the 

impacts given the brief period of work and type of activity will be temporary and minor. 

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Site 

No. 

Site Name 



TABLE 3.3.9-1: AUDIO ASSESSMENT MEASUREMENT RESULTS 

*Green shaded noise levels recorded while the Project was not operating (either pumping or generating). All other readings were taken while the facility was operating. 

E-196 

Average Baseline Noise Level (dBA)* 

Spring Summer Fall Winter 

Day Eve Day Eve Day Eve Day Eve 

Ave Min Max 

1 Turkey Island 48 52 50 56 54 57 52 57 53 48 57 

2 Lower Bear Island 44 44 43 53 50 52 46 52 48 43 53 

3 Big Chestnut Island 40 39 43 50 42 46 42 52 44 39 52 

4 Wissler’s Run Park 40 41 44 48 41 45 48 50 45 40 50 

5 Muddy Creek Boat Launch 39 39 41 55 49 54 41 47 46 39 55 

6 Lock 15 Interpretive Area 41 38 49 61 47 55 42 44 47 38 61 

7 Susquehannock State Park 46 37 46 57 44 58 40 49 47 37 58 

8 Cold Cabin Boat Launch 38 37 46 53 46 51 42 54 46 37 54 

9 Muddy Run Wildlife Mngt Area 37 34 45 59 46 54 42 43 45 34 59 

10 Muddy Run Recreation Park 41 36 45 52 42 50 43 43 44 36 52 

Ave 41 40 45 54 46 52 44 49 

Min 37 34 41 48 41 58 40 43 

Max 48 52 50 61 54 45 52 57



3.3.10. Socio-Economic Resources 

Socio-economic resource research and documentation involved accessing existing, relevant, and 

reasonably available information to determine the potential effects of the Project. 


3.3.10.1.1 Socio-economic Conditions 

The Project is located in Lancaster and York counties, Pennsylvania. The Muddy Run facility, including 

the pumped storage reservoir and powerhouse, are located in Lancaster County. The primary 

transmission line for the Project, which lies within the Project boundary and runs from the Muddy Run 

powerhouse to the PBAPS switchyard, is located in Peach Bottom Township, York County after crossing 

the Susquehanna River. 

Lancaster County. Lancaster County is located in southeastern Pennsylvania, encompassing 984 square 

miles. The Susquehanna River, which is located entirely within Lancaster County, serves as the western 

border of the County. Dauphin and Lebanon counties lie north of Lancaster County, while Berks and 

Chester counties lie east of Lancaster County. The City of Lancaster serves as the county seat. The 

Project Area is located in southern Lancaster County, about 30 miles south of the City of Lancaster, and 

35 miles northeast of the City of Baltimore, MD. Although the Project is located in a rural area of the 

County, it is within 50 miles of two relatively large Metropolitan Statistical Area (MSA) populations. 

The Philadelphia MSA (located northeast of the Project) has a population of 5.9 million people, and the 

Washington DC MSA (located southwest of the Project) has a population of 5.5 million people. (2010 

Census) 

Southern Lancaster County is largely rural in nature, and is dominated by agricultural land uses, which 

has shaped the history of the county. Today, Lancaster County is dependent upon agriculture 

(approximately 75% of the county contains lands within agricultural production) as well as manufacturing 

and tourism. Lancaster County is home to a concentrated population of Old Order Amish and 

Mennonites, who are well known for their distinctive religious beliefs and practices. Their religious 

practices do not permit their utilization of many modern conveniences and as such these religious groups 

are distinctive in their lifestyle. This population contributes significantly to the agricultural traditions of 

Lancaster County. 

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The Project is accessed via the State Route 3006 (River Road), which traverses the Muddy Run 

Reservoir’s main dam (access to the Muddy Run reservoir is prohibited due to safety concerns associated 

with the large water level fluctuations). The upper portion of the Muddy Run reservoir, which is 

separated from the main reservoir by the Project’s Recreation Pond Dike, is not subject to high fluctuation 

rates associated with the pumped storage operations. Public access is provided to this portion of the 

Project, and Exelon has constructed recreational facilities for this Project facility. The recreation 

reservoir is accessed by State Highway 372 (Holtwood Road). 

York County. York County is located in southeastern Pennsylvania, encompassing 910 square miles. It 

is bounded by the Susquehanna River to the east, while the southern boundary of the county comprises 

both the Pennsylvania Commonwealth boundary and the Mason Dixon Line. Adams County lies west of 

York County, while Cumberland County lies north of York County. The City of York serves as the 

county seat. The Project Area is located in southern Lancaster County, about 32 miles south of the City 

of Lancaster, and 35 miles northeast of the City of Baltimore, MD. The Project transmission line is not 

associated with any public access or recreational facilities. Although the Project is located in a rural area 

of the County, it is within 50 miles of two relatively large Metropolitan Statistical Area (MSA) 

populations. The Philadelphia MSA (located northeast of the Project) has a population of 5.9 million 

people, and the Washington DC MSA (located southwest of the Project) has a population of 5.5 million 

people. (2010 Census) 

The Project transmission line is located within Peach Bottom Township, along the western shore of the 

Susquehanna River. Southern York County is largely rural in nature, and is dominated by agricultural 

land uses. Today, while agriculture is an important industry within the County and a predominant land 

use in the southern portion of the county, it is a relatively small employer, providing only 500 out of the 

169,000 jobs in York County. The industries providing the largest amount of jobs in the county include 

manufacturing (34,000 jobs; 20% of the total jobs in York County) followed by health care (22,000 jobs; 

13% of the total jobs in York County) (EDC 2012). 

3.3.10.1.2 Population, Income, and Workforce 

Population. Population data for 1980 through 2020, and the change in population from 1990 to 2020, are 

provided in Tables 3.10.1.1-1 and 3.10.1.1-2, respectively. The population of both Lancaster and York 

counties has grown substantially between 1980 and 1990, and showed continued moderate growth 

between 1990 and 2010. The data also shows that while there has been significant growth in each of the 

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municipalities where the Project is located, the significant growth has been occurring outside the 

municipalities. The majority of the growth for both Lancaster and York counties has occurred within and 

adjacent to the more urban areas of the counties, including the cities of Lancaster and York, which serve 

as their respective county seats. 

From 1990 through 2010, both per capita income and median household income rose substantially, with 

the minimum increase of 73% median household income for the Commonwealth of Pennsylvania. The 

trend of note here is that while the Commonwealth showed a greater increase in per capita income in 

comparison to the counties, the counties showed a greater increase in median household income relative 

to the commonwealth over the same time period. 

Income. Personal income, a primary measure of personal buying power, is a key indicator in assessing 

community economic health. Personal income can be analyzed by a number of different indicators. For 

this assessment, per capita income and median household income are provided and discussed. The per 

capita income for the Commonwealth of Pennsylvania, Lancaster and York counties are provided in 

Table 3.3.10.1.2-3, while median household incomes are provided in Table 3.3.10.1.2.4. 

Workforce. Workforce statistics, most commonly analyzed in terms of unemployment rates, are a prime 

indicator of economic conditions. Civilian workforce and unemployment data for Pennsylvania, Lancaster 

and York County are provided in Table 3.10.1.2-5. Workforce statistics are consistent with larger trends, 

exhibiting growth in both total labor and employed from 1990 to 2000, however the economic downturn 

starting in 2007 has resulted in substantially higher levels of unemployment, and for the state a reduction 

in the number of people employed from 2010 compared to 2000. Lancaster County has shown a smaller 

growth in unemployment in the 2010 census compared to York County and all of Pennsylvania. 

Employment by Industry for Lancaster and York County. Employment by industry sector for 

Lancaster County has been compiled by the Economic Development Company of Lancaster County, PA. 

The two industries with the largest number of employees within the County are the Service industry 

(36.9%) (Including healthcare) and Manufacturing (14%). . 

In York County, employment by industry sector has been compiled by the Economic Development 

Company of York County, PA. The two industries with the largest number of employees within the 

County are the Service industry (43%) (including healthcare) and Manufacturing (20%). 

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3.3.10.1.3 Regional Benefits of the Project 

The Muddy Run Project has a positive effect on the local economies in Lancaster and York County. 

Project benefits include: (1) providing low-cost renewable power for citizens and industries, (2) paying 

local and state taxes, and (3) employment related to the operation and maintenance of the Muddy Run 

Project. 

Power Benefits. The Muddy Run Project produces on-peak, load-following, and voltage-regulation 

capabilities customary for a pumped storage Project and provides clean, efficient, reliable, and cost- 

effective hydroelectric power. The Muddy Run Project has a nameplate capacity of 800 MW. This 

amount of generating capacity is capable of providing the equivalent of approximately 600,000 local 

households with electricity each year, assuming one MW of power services an average of 750 households 

per year. 

Taxes. Exelon is subject to a variety of state, county, and local taxes. In 2011, these taxes totaled 

approximately $5 million. Taxes paid by Exelon positively affect the public as state taxes are deposited 

into general funds, which are directed, in part, back to the county and local governments. 

Employment Benefits. The Muddy Run Project is operated and maintained by 56 full-time employees. 

Exelon employees positively affect the local and regional economy by consuming goods and services, and 

paying taxes. 


The Project would be operated in substantially the same manner in which it has been historically 

operated, and would continue to supply low cost electricity, which is beneficial to the socioeconomic 

health of the region. 

Lancaster and York County are comprised of both urban areas as well as small rural communities. The 

counties have experienced modest to substantial growth rate over the past 30 years, while the 

Commonwealth has exhibited slow to no growth over the same time. Over the past 20 years, the counties 

have exhibited approximately equal per capita income, and substantially higher median household 

incomes and again approximately equal unemployment rates with the Commonwealth. 

The regional economy is predominantly service industry-based, with the manufacturing industry is a 

significant employer within the county. The service and retail trade industries are present largely as a 

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direct result of the tourist-based economy in Lancaster County, which contributes substantially to the 

regional economy of this natural resource rich region. County demographics indicate that the 

communities in the vicinity of the Project are similar to other towns in neighboring counties, and have not 

been adversely affected by the Project in terms of population, income, or employment opportunities. 

Importantly, the operation and maintenance of the Project coupled with taxes paid and energy generated 

have contributed to the economic and social benefits of the area in the immediate vicinity of the Muddy 

Run Project. The Project employs approximately 56 full-time staff who reside in the Project area, and 

provides economic benefits (e.g., taxes and services) to the area. 

Continued maintenance of the Project’s facilities, including recreation facilities, would result in some 

construction-related jobs, however, the labor force required would be very small (i.e., probably less than 

20 people) and would only be needed for a short time. 


The proposed Project likely has a beneficial effect on socio-economic resources; therefore, Exelon does 

not propose any measures related to socio-economic resources. 


The Muddy Run Project has no known unavoidable adverse effects on socioeconomic resources. 

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TABLE 3.3.10.1.2-1: POPULATION OF PENNSYLVANIA, LANCASTER AND YORK 

COUNTIES AND COMMUNITIES, 1980- 2020. 

Pennsylvania 

Commonwealth 

1980 

Census 

1990 

Census 

2000 

Census 

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2010 

Census 

2014 

Projection* 

2020 

Projection 

11,863,895 11,881,643 12,881,643 12,702,379 12,787,354 

Lancaster County 362,346 422,822 470,658 519,445 524,597 N/A 

Martic Township 3,286 4,362 4,990 5,190 4,968 N/A 

Drumore Township 1,682 2,114 2,243 2,560 2,271 N/A 

York County 312,963 339,547 381,751 434,972 N/A 450,887 

Peach Bottom Township 2,692 3,444 4,412 4,813 N/A N/A 

Source: EDC 2012, U.S. Census Bureau 2010, 2000, 1990, 1980. 

*Projections for 2014 populations presented by EDC were prepared for publication in 2009, and at the 

municipal level the growth projections are proven to be inconsistent with the actual counts from the 2010 

Census. While clearly incorrect, they have been included for demonstrative purposes.



TABLE 3.3.10.1.2-2: LANCASTER AND YORK COUNTIES AND COMMUNITIES 

POPULATION CHANGE, 1980-2020. 

Percent Change 

1980-1990 


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1990-2000 

Percent 

Change 

2000-2010 


Projection 

2010-2014/2020 

Pennsylvania Commonwealth 0.15% 8.4% -1.6% 0.6% 

Lancaster County 17% 11% 10% 1% 

Martic Township 33% 14% 4% -4% 

Drumore Township 26% 6% 14% -11% 

York County 8% 12% 14% 4% 

Source: EDC 2012, U.S. Census Bureau 2010, 2000, 1990, 1980. 

TABLE 3.3.10.1.2-3: PER CAPITA INCOME FOR PENNSYLVANIA, LANCASTER AND YORK 

COUNTY. 

1990 2000 2010 Percent Change 

Pennsylvania Commonwealth 14,068 20,880 $27,004 92% 

Lancaster County 14,235 20,398 24,871 75% 

York County 14,544 21,068 26,702 84% 

Source: U.S. Census Bureau 2010, 2000, 1990. 

TABLE 3.3.10.1.2-4: MEDIAN HOUSEHOLD INCOME FOR PENNSYLVANIA, LANCASTER 

AND YORK COUNTY. 

1990 2000 2010 Percent Change 

Pennsylvania Commonwealth $29,069 $40,106 $50,289 73% 

Lancaster County 33,255 45,507 65,390 97% 

York County 32,605 45,286 67,892 108% 

Source: U.S. Census Bureau 2010, 2000, 1990.



TABLE 3.3.10.1.2-5 PENNSYLVANIA, LANCASTER AND YORK COUNTY CIVILIAN LABOR 

FORCE DATA 

Total Civilian Labor 

Employed 

Unemployed 

(number/percent) 

Source: U.S. Census Bureau 2010, 2000, 1990. 

Pennsylvania Lancaster County York County 

1990 9,392,816 321,751 266,104 

2000 9,693,040 358,317 298,226 

2010 10,273,564 406,103 345,148 

1990 5,434,532 215,292 176,908 

2000 6,000,512 235,686 195,926 

2010 5,842,790 249,828 215,887 

1990 334,795/3.5 6,921/3.2 7,045/3.9 

2000 339,386/3.5 7,329/2.0 7,301/2.4 

2010 620,700/9.6 21,349/7.9 23,289/9.7 

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3.4. No-Action Alternative 

Under the No-action Alternative, the existing Project would continue to operate as it has historically 

operated as described in Section 2.1. The measures in the current licenses as described in Section 2.1 

would continue - none of Exelon’s proposed measures or those that may be proposed by others would be 

required and any environmental or recreation benefits from such recommendations would not occur. The 

Project would continue to be of importance to recreation, generation of renewable energy, and 

minimization of atmospheric pollutants. 

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SECTION 4.0 



DEVELOPMENTAL ANALYSIS 

This section analyzes the cost of continued operation and maintenance of the Project under the No Action 

and Proposed Alternatives. Costs are associated with the operation and maintenance of hydropower 

facilities, as well as the costs of providing the proposed protection, mitigation, and enhancement (PM&E) 

measures. The economic analysis has been conducted using a 46-year time period. 

4.1. Power and Economic Benefits of the Project 

4.1.1. Economic Assumptions 

Under its approach to evaluating the economics of hydropower projects as articulated in Mead 

Corporation, Publishing Paper Division (72 FERC 61,027, July 13, 1995), the Commission employs an 

analysis that uses current costs to compare the costs of a Project and likely alternative power with no 

consideration for potential future inflation, escalation, or deflation beyond the license issuance date. The 

Commission’s economic analysis provides a general estimate of the potential power benefits and costs of 

a project and reasonable alternatives to project-generated power. The estimate helps to support an 

informed decision concerning what is in the public interest with respect to a proposed license. For the 

economic analysis of the Project, assumptions, values, and sources are shown in Table 4.1.1-1. 

TABLE 4.1.1-1: ASSUMPTIONS FOR ECONOMIC ANALYSIS 

Assumption Value Source of Information 

Average Power Value (Generation) (2011 value) 21 $70.25 Exelon 

Average Power Value (Pumping) (2011 value) 22 $32.77 Exelon 

Average Annual Generation (MWh) 23 1,739,000 Exelon, Oasis Model 

Average Annual Energy for Pumping (MWh) 24 2,261,000 Exelon, Oasis Model 

Period of Analysis 46 years --- 

Net Investment (book value) 25 $140,505,000 

Exelon 

Capacity Value 26 (2011 value) 27 $136.60 per MW-day Exelon 

Ancillary Services (2011 value) $10,819,000 Exelon 

21 

This is a realized 2011 power value, which is calculated as annual revenue divided by annual generation. 

22 

This is a realized 2011 power value, which is calculated as annual cost divided by annual energy for pumping. 

23 

Average annual generation from Exelon’s OASIS operations model based on hydrology from 1930-2007. 

24 

Average annual energy for pumping from Exelon’s OASIS operations model based on hydrology from 1930- 

2007. 

25 

Does not include construction projects currently in progress. 

26 

The capacity associated with Muddy Run is 1060.6 MW. 

27 

Capacity value is from the clearing price from PJM and based on the 2011 planning year. 

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To estimate generation under Exelon’s Proposed Alternative as described in Exhibit E-Section 2.2, as 

well as under various alternatives including the No Action Alternative, Exelon developed an operations 

model of the Lower Susquehanna River using the OASIS modeling software. The model simulates the 

operation of the Safe Harbor, Holtwood, Muddy Run, and Conowingo Projects utilizing synthetic inflow 

hydrology and operating rules. See Exhibit B for a description of the operations model. 

4.1.2. Annual Power Value 

Table 4.1.2-1 shows the total valuation of power for the No Action and Proposed Alternatives. For both 

scenarios, this assumes an average annual generation of 1,739,000 MWh. In addition, the analysis 

assumes use of 2,261,000 MWh annually. 

The annual market value of the energy and capacity is $111,771,000, or $64.27 per MWh, for both the No 

Action and Proposed Alternatives. 

TABLE 4.1.2-1: VALUATION OF THE ANNUAL OUTPUT OF THE MUDDY RUN PROJECT 28 

No Action Proposed 

Energy Generated at $70.25 (for 1,739,000 MWh) $122,165,000 $122,165,000 

Energy for Pumping at $32.77 (for 2,261,000 MWh) ($74,093,000) ($74,093,000) 

UCAP at $136.60 per MW-day (1,060.6 MW) 29 $52,880,000 $52,880,000 

Ancillary Services $10,819,000 $10,819,000 

Total Value (Energy + Ancillary Services + UCAP) $111,771,000 $111,771,000 

Total value per MWh (generated) $64.27 $64.27 

4.1.3. Project Costs under No-Action Alternative 

The total annualized current costs for the Project No-Action Alternative is $51,677,000 (Table 4.1.3-1). 

28 Annual output calculations are based on 2011 realized power, capacity, and ancillary services values. 

29 Capacity value for 2011 is approximately $52.880 million (1060.6 MW * $136.60/MW-day * 365days/yr.) 

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TABLE 4.1.3-1: SUMMARY OF ANNUAL COSTS UNDER THE NO ACTION ALTERNATIVE. 

Item Annual Cost 

Capital Costs $10,167,000 

Local, State and Federal Taxes 30 $31,324,000 

Annual Depreciation and Amortization Expense 31 $3,329,000 

Operation and Maintenance Expenses 32 $6,857,000 

Total $51,677,000 

4.1.4. Project Costs under Proposed Alternative 

Exelon proposes several environmental measures (Table 4.1.4-1) for inclusion in the new license for the 

Project. The measures would add capital costs, and increase annual operations and maintenance costs for 

the Project. 

TABLE 4.1.4-1: SUMMARY OF ANNUALIZED COSTS (2014 DOLLARS) FOR 

ENVIRONMENTAL AND RECREATION MEASURES 

PME Measure Total Capital Cost 

over 46 Years (2014 

dollars) 

E-208 

Total O&M Cost over 

46 Years (2014 

dollars) 

Bald Eagle Management $0 $53,000 $1,000 

Bog Turtle Management $0 $582,000 $13,000 

Recreation Management $3,607,000 $3,151,000 $147,000 

Shoreline Management TBD TBD TBD 

Historic Properties Management $8,000 $0 $0 

Cost to Prepare Application for 

a New License 33 

$7,026,000 $0 $153,000 

Total $10,641,000 $3,786,000 $314,000 

4.2. Comparison of Alternatives 

Average Annual 

Cost over 46 Years 

(2014 dollars) 

Table 4.2-1 compares the power value, annual costs, and net benefits of Exelon’s No Action and 

Proposed Alternative for the Project. 

30 As described in Exhibit D, Section 4.2. 



33 As described in Exhibit D, Section 7.0.



4.2.1. No Action Alternative 

Under the No Action Alternative, the project would continue to operate as it does now. The project 

generates an average of 1,739,000 MWh of electricity annually. The average annual power value of the 

project under the no-action alternative would be $111,772,000 ($64.27/MWh). The average annual cost of 

producing this power would be $51,677,000 ($29.72/MWh). The resulting annual net benefit of the 

project would be about $60,095,000 ($34.56/MWh). 

4.2.2. Proposed Alternative 

Under the Proposed Alternative, the average annual generation would remain 1,739,000 MWh. The 

Project would have an average annual power value of $111,772,000 ($64.27/MWh), an average 

production cost of $51,966,000 ($29.88/MWh), and an annual net benefit of about $59,806,000 

($34.39/MWh). 

TABLE 4.2-1: COMPARISON OF THE POWER VALUE, ANNUAL COSTS, AND NET 

BENEFITS OF THE NO ACTION AND PROPOSED ALTERNATIVES. 

No Action Alternative Proposed Alternative 

Annual Generation (MWh) 1,739,000 1,739,000 

Annual Power value: Annual Net 

Generation 

$ per year $111,772,000 $111,772,000 

$/MWh $64.27 $64.27 

Annual Costs 

$ per year $51,677,000 $51,966,000 

$/MWh $29.72 $29.88 

Annual Net Benefits 

$ per year $60,095,000 $59,806,000 

$/MWh $34.56 $34.39 

E-209

SECTION 5.0 



CONCLUSIONS 

5.1. Comparison of Alternatives 

This section compares the developmental and non-developmental effects of Exelon’s proposed Project 

and the No-Action Alternative. 

5.2. Comparison Development and Recommended Alternative 

Sections 4(e) and 10(a) of the FPA require the Commission to give equal consideration to all uses of the 

waterway on which a project is located. When FERC reviews a hydropower project, FERC considers the 

water quality, fish and wildlife, recreational, and other non-developmental values of the involved 

waterway equally with its electric energy and other developmental values. Accordingly, any license 

issued shall be best adapted to a comprehensive plan for improving or developing a waterway or 

waterways for all beneficial public uses. 

5.3. Unavoidable Adverse Effects 

Exelon has performed numerous studies for the relicensing of the Muddy Run Project. These studies 

have identified that with the continued operation of the Muddy Run Project, the following unavoidable 

adverse effects will occur. 

� Minor erosion will continue to occur as a result of the fluctuation of the Power Reservoir. 

� Dissolved oxygen stratification will occur in the Power Reservoir during the warmest time of the 

year. 

� The existing littoral zone will be impacted by the continued fluctuation of the Power Reservoir, 

which is inherent in the operation of a pumped storage hydroelectric facility. 

� The existing transmission line will continue to result in limited adverse impacts to avian species, 

including the osprey and bald eagle. 

� The continued operation of the Project will have a minor impact on noise and aesthetic resources. 

5.4. Consistency with Comprehensive Plans 

Section 10(a)(2)(A) of the FPA requires the Commission to consider the extent to which a project is 

consistent with federal and state comprehensive plans for improving, developing, or conserving 

waterways affected by the Project. On April 27, 1988, FERC issued Order No. 481-A revising Order No. 

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481, issued October 26, 1987, establishing that FERC will give FPA Section 10(a)(2)(A) comprehensive 

plan status to any federal or State plan that meet the following three criteria: 

� It is a comprehensive study of one or more of the beneficial uses of a waterway or waterways; 

� It specifies the standards, the data, and the methodology used to develop the plan; and 

� It is filed with FERC. 

FERC’s Revised List of Comprehensive Plans, dated April 2011, can be found at FERC’s eLibrary 

(http://www.ferc.gov/industries/hydropower/gen-info/licensing/ complan.pdf). As required by 18 CFR § 

5.18(b)(5)(ii)(F), this section provides an explanation of how and why the proposed Project would, 

would not, or should not comply with each of the plans, or in some cases, directs the reader to the 

appropriate section of the Final License Application (FLA) for an in depth discussion of compliance with 

the plan. To facilitate FERC’s review, the plans are discussed below in the order presented by FERC in 

its Scoping Document 2 (SD2), as amended, and the full reference for each plan is provided. As of the 

time the FLA is filed, relevant resource agencies have not made a determination regarding the consistency 

of the proposed Project with any qualifying comprehensive plans. 

� Atlantic States Marine Fisheries Commission. 2003. Fishery Management Report No. 41 of the 

Atlantic States Marine Fisheries Commission. (Amendment 5 and 6 to the Interstate Fishery 

Management Plan for Atlantic Striped Bass). January 1995, February 2003. 

The Atlantic States Marine Fisheries Commission (ASMFC) 2003 Fishery Management Plan 

(FMP) for Atlantic Striped Bass was implemented to better manage this species given the popularity of 

this species to fishermen, the complex nature of its seasonal distribution, and decline in harvest and poor 

recruitment during the 1970’s. Amendment 5 of this FMP established the management program for the 

newly recovered striped bass stock. Since 1995 five addenda have been developed and implemented to 

respond to changing circumstances in the fishery. Amendment 6 was developed to address the 

management complexity as well as a number of other issues that may arise with the continued 

management of the species. 

The Susquehanna River at the Muddy Run Project was subject to the intentional introductions of hybrid 

fishes for recreational angling, including the striped bass. The fish is no longer stocked in Conowingo 

Pond. The Project is able to provide habitat for the species, and is consistent with this management plan. 

� Atlantic States Marine Fisheries Commission. 1998. Amendment 1 to the Interstate fishery 

management plan for Atlantic sturgeon (Acipenser oxyrhynchus). (Report No. 31) July 1998. 

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The Atlantic States Marine Fisheries Commission (ASMFC) 1990 Fishery Management Plan 

(FMP) for Atlantic Sturgeon was implemented to better manage the species throughout its U.S. range. In 

1996, the ASMFC decided to amend the plan with the goal of restoring Atlantic sturgeon 

spawning stocks to population levels which will provide for sustainable fisheries, and ensure 

viable spawning populations. The objectives of the Amendment are incorporated through the use 

of specific management measures whose goals are to establish 20 protected year classes of females in 

each spawning stock; close the fishery for a sufficient time period to reestablish spawning stocks and 

increase numbers in current spawning stocks; determine the spawning sites and provide protection of 

spawning habitats for each spawning stock; reduce or eliminate bycatch mortality of Atlantic sturgeon; 

where feasible, reestablish access to historical spawning habitats for Atlantic sturgeon; and conduct 

appropriate research as needed, especially to define unit stocks of Atlantic sturgeon. 

The Atlantic sturgeon is not known to inhabit Project waters. The Project is consistent with this 

management plan. 

� Atlantic States Marine Fisheries Commission. 2000. Amendment 3 of the Interstate Fishery 

Management Plan for shad and river herring. February, 2010. 

The goal of the Management Plan is to protect, enhance, and restore east coast migratory spawning 

stocks of American shad, hickory shad, and river herrings in order to achieve stock restoration 

and maintain sustainable levels of spawning stock biomass. Objectives identified in the plan were to 

prevent overfishing of American shad stocks by constraining fishing mortality; develop definitions of 

stock restoration, determine appropriate target morality rates and specify rebuilding schedules for 

American shad populations within the management unit; maintain existing or more conservative 

regulations for hickory shad and river herring fisheries until new stock assessments suggest changes are 

necessary; and promote improvements in degraded or historic alosine habitat throughout the species 

range. 

States were required to submit fishing recovery plans by July 1999 and annual monitoring reports 

thereafter. Mandatory fishery monitoring programs for American shad in the Susquehanna River 

identified in the FMP included annual spawning stock survey and representative sampling for 

biological data; calculation of mortality and/or survival estimates; recovery of any visibly marked 

animals; juvenile abundance survey; and hatchery evaluation. The FMP recommended monitoring 

programs for juvenile river herring and hickory shad in the Susquehanna River included weekly seining 

from July through October and twice weekly lift nets at Holtwood. 

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The continued operation of the Project will not have a significant impact on the shad and river herring 

population of the Susquehanna River, and is therefore consistent with this management plan. 

� Atlantic States Marine Fisheries Commission. 2000. Addendum II of the Interstate Fishery 

Management Plan for American eel (Anguilla rostrata). (Report No. 36). October, 2008. 

The FMP for the American eel was developed by the ASMFC to protect and restore the species. The goal 

of the FMP is to conserve and protect the American eel resource to ensure its continued role in the 

ecosystems while providing the opportunity for its commercial, recreational, scientific, and 

educational use. The primary objectives are to improve knowledge of eel utilization at all life stages 

through mandatory reporting of harvest and effort by commercial fishers and dealers, and 

enhanced recreational fisheries monitoring; increase understanding of factors affecting eel 

population dynamics and life history through increased research and monitoring; protect and enhance 

American eel abundance in all watersheds where eel now occur; where practical, restore American 

eel to those waters where they had historical abundance but may now be absent by providing access 

to inland waters for glass eel, elvers, and yellow eel and adequate escapement to the ocean for pre- 

spawning adult eel; investigate the abundance level of eel at the various life stages, necessary to 

provide adequate forage for natural predators and support ecosystem health and food chain structure. 

The continued operation of the Project will not have a significant impact on the eel population of the 

Susquehanna River, and is therefore consistent with this management plan. 

� National Marine Fisheries Service. 1998. Final Recovery Plan for the shortnose sturgeon (Acipenser 

brevirostrum). Prepared by the Shortnose Sturgeon Recovery Team for the National Marine Fisheries 

Service, Silver Spring, Maryland. December 1998. 

The Shortnose Sturgeon Recovery Plan was drafted by a seven-member recovery team comprising staff 

from federal, state and private institutions with both fishery research and management backgrounds with 

assistance of a group of "Technical Advisors" with diverse expertise in sturgeon research and 

management and species recovery planning. The Recovery Plan consists of four primary sections: 1) an 

updated synopsis of the biology and distribution of shortnose sturgeon; 2) a description of factors 

affecting species recovery; 3) an outline of actions needed to recover shortnose sturgeon; and 4) a detailed 

implementation schedule for completing specific recovery tasks. It is anticipated that the Recovery Plan 

will be periodically revised by the NMFS or a NMFS-appointed plan implementation team to reflect new 

scientific findings, reclassification and recovery of individual population segments, and improved 

understanding of factors affecting population survival. 

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Consultation with National Marine Fisheries Service staff has indicated that they do not support passing 

the shortnose sturgeon above the Conowingo Dam, located downstream of the Muddy Run Project. With 

the shortnose sturgeon not present at the Muddy Run Project, the Project is consistent with this 

management plan. 

� National Park Service. The nationwide rivers inventory. Department of the Interior, Washington, D.C. 

1993. 

The Nationwide Rivers Inventory (NRI) is a listing by the Park Service of more than 2,400 free-flowing 

river segments in the United States that are believed to possess one or more “outstandingly remarkable” 

natural or cultural values judged to be greater than local or regional significance. In addition to these 

eligibility criteria, river segments are divided into three classifications: Wild, Scenic, and Recreational 

river areas. Under a 1979 Presidential Directive and related Council on Environmental Quality 

procedures, all federal agencies must seek to avoid or mitigate actions that would adversely affect one or 

more NRI segments. 

The Muddy Run Project does not alter the current flows or character of any listed river segments to the 

extent that the Park Service’s classifications of the river segments would change, and is therefore 

consistent with this inventory. 

� Pennsylvania Department of Environmental Protection. 2009. Pennsylvania State Water Plan. 

Harrisburg, Pennsylvania. January 2009. 

The Pennsylvania State Water Plan was designed to evaluate and balance the water needs of 

multiple users and to avoid potential conflicts that may develop between competing water users. The 

Plan identifies critical water resource planning areas where the demand for water may exceed available 

supplies. Designation of such an area triggers more intensive planning efforts. 

There is no designated critical water resource planning area in or anywhere near the Project. This current 

State Water Plan contains no provisions specific to the Muddy Run Project. 

� Pennsylvania Department of Environmental Protection. 2006. Pennsylvania’s recreation plan, 2004- 

2008. Harrisburg, Pennsylvania. 

Pennsylvania’s Recreation Plan for 2004-2008, prepared by the Pennsylvania Department of 

Conservation and Natural Resource was published in April of 2004 in order to provide a vision 

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for the future of recreation in Pennsylvania. The Pennsylvania Recreation Plan serves the following 

purposes: 

� It serves as the Commonwealth’s official policy document for identifying recreational issues, 

needs, policies, and capital investment priorities. 

� It is a guide for the acquisition, development, rehabilitation, and protection of resources and 

provision of recreational opportunities and services to the State’s citizens and visitors. 

� It provides a framework ensuring the protection of Pennsylvania’s highly valued cultural and 

natural resources, and enhancing existing recreational opportunities within the Commonwealth. 

� This Plan contains no provisions specific to the Muddy Run Project. However, the Project is 

consistent with the goals of the Plan by providing public access and recreational opportunities to the 

Susquehanna River for residents of the Commonwealth of Pennsylvania, and is therefore consistent 

with this management plan. 

� Pennsylvania Department of Conservation and Natural Resources. 2010. The Pennsylvania Scenic 

Rivers Program Scenic Rivers Inventory. http://www.dcnr.state.pa.us/brc/rivers/scenicrivers/ 

Harrisburg, Pennsylvania. 

The Pennsylvania Scenic Rivers Program Scenic Rivers Inventory, prepared by the Pennsylvania 

Department of Conservation and Natural Resources, does not currently list the Susquehanna River as a 

State or Federally designated Scenic River. 

� Susquehanna River Basin Commission. 2008. Comprehensive plan for management and development 

of the water resources of the Susquehanna River Basin. Harrisburg, Pennsylvania. December 2008. 

The Susquehanna River Basin Commission (SRBC) developed this management plan to provide a 

framework to manage and develop the basin’s water resources and to serve as a guide for all 

SRBC programs and activities. The plan is focused on six key water resource needs identified 

as priority management areas which include water supply; water quality; flooding; ecosystems; 

Chesapeake Bay; and coordination, cooperation, and public information. Within these priority 

management areas, SRBC identified 12 areas of special interest. Those areas of special interests related 

to the Muddy Run Project include energy production, flood forecast and warning, migratory fish 

restoration, and water and wastewater infrastructure. 

The Muddy Run Project is consistent with the management objectives associated with hydropower 

development on the Susquehanna River, and is therefore consistent with this management plan. 

� U.S. Fish and Wildlife Service. 1989. Chesapeake Bay striped bass management plan. Annapolis, 

Maryland. December 1989. 

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The Chesapeake Bay Striped Bass Management Plan was under a strategy of the Living 

Resources Commitments of 1987 Chesapeake Bay Agreement. The goal of the plan is to 

enhance and perpetuate the striped bass stock in Chesapeake Bay and its tributaries, and 

throughout its Atlantic coast range, to generate optimum long-term ecological, social, and 

economic benefits. The primary objective of the plan is to abide by the ASMFC guidelines and 

requirements, but a number of other objectives and management problems as well as strategies 

were identified. 

The Susquehanna River at the Muddy Run Project was subject to the intentional introductions of hybrid 

fishes for recreational angling, including the striped bass. The fish is no longer stocked in Conowingo 

Pond. The Project is able to provide habitat for the species, and is consistent with this management plan. 

� U.S. Fish and Wildlife Service. 1989. Chesapeake Bay Alosid (shad and river herring) management 

plan. Annapolis, Maryland. July 1989. 

The Chesapeake Bay Alosid Management Plan has been developed to protect, restore, and enhance 

baywide shad and river herring stocks to generate the greatest long-term ecological, economic, 

and social benefits from the resource. The goals of the plan are to maintain a spawning stock at a size 

which eliminates low reproductive potential as a cause of poor spawning success; promote protection of 

the resource by maintaining a clear distinction between conservation goals and allocation issues; 

reduce fishing effort on alosid stocks until they exhibit increased abundance; improve knowledge of 

alosid stock dynamics to develop more accurate databases and minimize interjurisdictional conflicts; 

redefine the tributary survey program to improve water quality and habitat accessibility; and continue 

restocking programs into areas which historically supported natural spawning migrations and to 

expand existing stock restoration programs to include areas which do not presently support alosids. The 

Project is consistent with this plan. 

The continued operation of the Project will not have a significant impact on the shad and river herring 

population of the Susquehanna River, and is therefore consistent with this management plan. 

� U.S. Fish and Wildlife Service. 1992. Chesapeake Bay American eel fishery management plan. 

Annapolis, Maryland. December 18, 1992. 

The Chesapeake Bay American Eel Fisheries Management Plan was developed as part of the Living 

Resources Commitments of 1987 Chesapeake Bay Agreement. The goal identified in the plan is to 

manage the American eel harvest in the Chesapeake Bay and its tributaries so that harvest does not 

E-216



exceed the reproductive capacity of the population to maintain its size from year to year. The objectives 

of the goal are to promote protection of the resource by maintaining a clear distinction between 

conservation goals and harvest regulations; restore self-sustaining population of American eels to 

their historical ranges; implement appropriate monitoring programs necessary for collecting stock 

assessment data; provide for fair allocation of allowable harvest, consistent with traditional uses, among 

the various components of the fishery; promote studies to improve the understanding of economic, social, 

and biological aspects of the fishery; and continue to pursue and enforce standards of environmental 

quality and habitat protection necessary to protect the American eel population within the Bay 

and its tributaries. 

The continued operation of the Project will not have a significant impact on the American eel population 

of the Susquehanna River, and is therefore consistent with this management plan. 

� U.S. Fish and Wildlife Service. Undated. Fisheries USA: the recreational fisheries policy of the U.S. 

Fish and Wildlife Service. Washington, D.C. 

The Recreational Fisheries Policy defines the U.S. Fish and Wildlife Service’s (USFWS) 

stewardship role in the management of the United States’ recreational fishery resources. The 

USFWS is committed to promoting and enhancing freshwater, anadromous, and coastal fishery resources 

for long-term public benefit. This commitment is outlined by the following policies: 

1. Preserve, restore, and enhance fish populations and their habitats. 

2. Promote recreational fishing on USFWS and other lands to provide the public with a high quality 

recreational experience. 

3. Ensure that recommendations concerning recreational fisheries potentials and opportunities are 

included as part of appropriate field studies and management assistance efforts performed by the 

USFWS on non-USFWS waters. 

4. Serve as an active partner with other Federal governmental agencies, States, Tribes, 

conservation organizations, and the public in developing recreational fisheries programs. 

5. Promote the conservation and enhancement of the Nation’s recreational fisheries through the 

USFWS’s grant in aid programs. 

6. Improve and expand quantifiable economic valuations of the Nation’s recreational fisheries to 

demonstrate the importance of this resource to the health and welfare of our society and to the Nation’s 

economy. 

To accomplish these policies, the USFWS developed the following goals and strategies: 

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1. Effect the preservation and/or increased productivity of fishery resources. 

2. Ensure and enhance the quality, quantity, and diversity of recreational fishing opportunities. 

3. Develop and enhance partnerships between governments and the private sector for conserving 

and managing recreational fisheries. 

4. Cooperate and maintain a healthy recreational fisheries industry. 

The Muddy Run Project provides recreational fishing opportunities at both the upper Power Reservoir 

and the Conowingo Pond. The continued operation of the Project will serve to ensure and enhance the 

quality, quantity, and diversity of recreational fishing opportunities and maintain a healthy recreational 

fishing industry. Consequently, the Muddy Run Project is consistent with this management plan. 

� U.S. Fish and Wildlife Service. 2010. Migratory Fish Management and Restoration Plan for the 

Susquehanna River Basin. Harrisburg, Pennsylvania. November 15, 2010. 

This plan was developed to serve as the Susquehanna River Anadromous Fish Restoration 

Cooperative’s (SRAFRC) restoration guide and management plan for migratory fish resources. 

The goal of the plan is to “restore self-sustaining, robust, and productive stocks of migratory fish capable 

of producing sustainable fisheries, to the Susquehanna River Basin throughout their historic ranges 

in Maryland, Pennsylvania, and New York. The goals are 2 million American shad and 5 

million river herring spawning upstream of the York Haven Dam.” 

The continued operation of the Project will not have a significant impact on migratory fish populations 

in the Susquehanna River. Consequently, the Project is consistent with this management plan. 

E-218

SECTION 6.0 



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E-228

SECTION 7.0 



CONSULTATION DOCUMENTATION 

Throughout the Integrated Licensing Process, Exelon has engaged in substantive consultation with 

relicensing participants, and have filed all licensing materials with FERC. Names and addresses for 

federal, state, and interstate resource agencies, Indian tribes, or members of the public with which Exelon 

has consulted during relicensing, and a comprehensive summary of all consultation activities between 

filing of the Proposed Study Plan on August 24, 2009 and submittal of the Final License Application are 

included in this Final License Application. 

E-229



Stephanie Almoney 

47 Kings Way 

Stewartstown PA 17363 

Guy Alsentzer 

Lower Susquehanna Riverkeeper 

324 West Market 

York, PA 17401 

Andrea Anderson 

122 East McKinley Rd 


Michele & Lowel Anderson 

100 Grove Road 

Red Lion, PA 17356 

Mr. Mark Arbogast 

118 North Decatur Street 

Strasburg, PA 17579 

Mr. Charles Arbough 

10523 Howard Ave 

Cockeysville, MD 21030 

Tonda Arbough 

5 Banat Court 

Baltimore, MD 21237 

Mr. Matt Ashton 

Maryland Department of Natural 

Resources 

Natural Resource Biologist III 

Monitoring and Non-tidal Assessment 

580 Taylor Ave., C-2 

Annapolis, MD 21401 

Mr. David Axe 

71 West McKinley Road 


Mr. John W. Balay 

Susquehanna River Basin Commission 

Water Resources Management, 

Hydrologist 

1721 North Front Street 

Harrisburg, PA 17102-2391 

Alex Balboa 

1996 Waverly Drive 

Bel Air, MD 21015-1100 

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Paula Ballaron 




Ross Bare 

255 Seitz Road 

Columbia, PA 17512 

William Bates 

3586 Day Road 

Darlington, MD 21034 

Mr. Thomas W. Beauduy 


Deputy Director 



Robert Bennett 

117 Dallas Ave 

Newark, DE 19711 

Heidi Biggs 

Pennsylvania Fish and Boat 

Commission 450 Robinson Lane 

Bellefonte, PA 16823 

Catherine Bilger 

183 Gemmill Road 


Beth & Bill Birchall 

303 Tucquan Glen Road 

Holtwood, PA 17532 

Judy Blomquist 

1009 Morrison 

Havre de Grace, MD 21078 

Mr. Al Blott 

National Marine Fisheries Service 

113 Bruce Boyer Street 

PO Box 1692 

North Kingstown, RI 02852 

Mary Boomsma 

144 Stubler Mill Road 

Peach Bottom, PA 17563



Emilee Boyer 

Pennsylvania Department of 

Conservation and Natural Resources 

Environmental Review Specialist 

P.O. Box 8552 

Harrisburg, PA 17105 

Dorcia Bradley 

1920 Rivervue Drive 

Drumore, PA 17520 

John Bradley 

1920 Rivervue Drive 


Garry Brannaw 

PO Box 207 


Tom Brant 

York County Parks Department 

400 Mundis Race Road 


Ms. Olivia A. Braun 

Pennsylvania Game Commission 

Environmental Planner 

2001 Elmerton Avenue 

Harrisburg, Harrisburg, PA 17110- 

9797 

Mr. Jere J. Brooks 

1653 Rawlinsville Road 


Mr. Joe Brooks 

23 Stone Moss Dr 

Newnan, GA 30265 

Bernie Brown 

124 Mt Zoar Road 

Conowingo, MD 

Michael G. Brownell, Chief 




Christine C. Brubaker 

22 Birch Ct 


E-231 

Mr. Mark Bryer 

The Nature Conservancy 

Director, Chesapeake Bay Program 

5410 Grosvenor Lane, Suite 100 

Bethesda, MD 20814 

Susan Burdette 

602 Trout Dale Terrace 

Bel Air, MD 21014 

Mr. Richard A. Cairo 


General Counsel 



Mr. Robert B. Campbell 

Mason-Dixon Trail System 

PA Director 

811 Marvell Drive 


Cynthia Cantor 

17 Wilson Road 

Rising Sun, MD 

Bill Capouillez 




Honorable Ben L. Cardin 

United States Senate 

Senator 

509 Hart Senate Office Bldg 

Washington, D.C. 20510 

Brigitte Carty 

4948 Conowingo Road 

Darlington, MD 

Skip Cauler 

186 Indian Run Road 

Millerville, PA 17551 

Ed Cheslock 

P.O. Box 82 

Delta, PA 17314



Mr. Michael Chezik 

U.S. Department of the Interior - 

Office of the Secretary 

Regional Environmental Officer 

200 Chestnut Street 

Custom House, Room 244 

Philadelphia, PA 19106-2904 

Mr. Doug Clark 

Coastal Conservation Association 

Maryland Chapter, 101 Ridgely Ave., 

Suite 12A 


Mr. Kevin Colburn 

American Whitewater 

National Stewardship Director 

1035 Van Buren Street 

Missoula, MT 59802 

Mary Colligan 

National Marine Fisheries Service, 

Northeast Regional Office- 

DOC/NOAA 

Assistant Regional Administrator for 

Protected Resources 

55 Great Republic Drive 

Gloucestar, MA 01930-2276 

Peter Collins 

1745 Jumpers Ct 

Jarrettsville, MD 21084 

Mr. Wade Cope 


1721 N. Front Street 


Ben Cox 

1521 Kerr Road 

Whiteford, MD 21160 

Julie Crocker 



DOC/NOAA 

Protected Resources Division 

NMFS/NERO 


Gloucester, MA 01930 

E-232 

Mr. Phil Cwiek 

U.S. Army Corps of Engineers, 

Baltimore District 

Attn: CENAB-OP-RMN 

P.O. Box 1715 

Baltimore, MD 21203-1715 

Bob Dach 

U.S. Bureau of Indian Affairs Natural 

Resources 

Hydropower Program Director 

911 NE 11th Avenue 

Portland, OR 97232 

Kimberly Damon-Randall 



DOC/NOAA 



Joseph DaVia 

U.S. Army Corps of Engineers 

P.O. Box 1715 


David M. Davidson Jr. Director 

Stewards of the Lower Susquehanna 

Inc. 

324 W Market St 

York, PA 17401-1010 

Mr. Steve Davis 

U.S. Fish and Wildlife Service 

Fish Culture Facility Maintenance 

Northeast Fishery Center 

308 Washington Ave., P.O. Box 75 

Lamar, PA 16848 

Mr. Kenneth L. Dearolf Jr. 

Federated Sportsmen of Lancaster 

County 

Secretary 

4134 Jasmine Place 

Mount Joy, PA 17552 

Mr. Andrew Dehoff 



Harrisburg, PA 17102-2391



Felicia S. Dell 

York County Planning Commission 

Director 

28 East Market Street, 3rd Floor 


Mr. Thomas L. Denslinger P.E. 


Environmental Protection 

Chief, Water Use Management Section 

P.O. Box 8555 


Mr. David Densmore 


Pennsylvania Field Office 

315 S. Allen St. Suite 322 

State College, PA 16801 

Michele M. DePhilip 

The Nature Conservancy In 

Pennsylvania 

Director - Freshwater Conservation 

2101 N Front Street 


Bonnie Dershem 

US Fish and Wildlife Service 

Endangered Species Biologist 

315 South Allen Street, Suite 322 


Sara Deuling 

American Rivers 

355 North 21st Street, Suite 309 

Camp Hill, PA 17011 

John L. Devney 

Delta Waterfowl Foundation 

Senior Vice President 

Delta Waterfowl Foundation 

PO Box 3128 

Bismarck, ND 58502 

Maryanne Dolan 

Cecil Bird Club 

104 Milestone Road 

Elkton, MD 21921 

E-233 

Michael A Domin AICP 


Commission 

Principal Planner 

150 North Queen Street, Suite 320 


Amy Donohue 

657 East Posey Road 


Brian Dorsey 

Susquehanna Surf Society 

404 McFadden Rd 

Pylesville, MD 21132 

Tom Dunlap 

2542 Holtwood Road 


Nick Ebersole 

Lancaster County Conservancy 

117 West End Eve 


Mr. Ray Eckelmeyer 

9737 High Rock Road 


Mrs. Clara Eckelmeyer 

9737 High Rock Road 


Mr. Steve Elinsky 


P.O. Box 1715 


Sheila Eyler 

U.S. Fish and Wildlife Service, 

Maryland Fishery Resources Office 

177 Admiral Cochrane Drive 


Dennis R. Felts 

61 West McKinely Rd 


Mary L. Frey 


Commission 

Principal Planner 

150 North Queen Street, Suite 320 

Lancaster, PA 17603



Ms. Cynthia Fuhrer 

Susquehanna Heritage 

1706 Longhevel Road 


Margaret E. Gaffney-Smith 


Chief, Regulatory Branch 

P.O. Box 1715 


Mr. Robert Gallagher 

West/Rhode Riverkeeper, Inc. 

4800 Atwell Road, #6 

Shady Side, MD 20764 

Julie Gantenbein 

Natural Heritage Institute 

100 Pine St., Ste. 1550 

San Francisco, CA 94111 

Mr. Andrew Gavin 




Robert & May Gaynor 

312 Miller Street 

Strasburg, PA 17579 

David Glenn 

295 Slab Road 


Kate Shirk Gonick J.D., M.A. 


117 W End Ave 


Mr. Daniel C. Good 

135 Ridge Road 

Millersville, PA 17551 

Mr. Ralph Goodno 


President & CEO 

117 South West End Avenue 


Melissa Grader 


New England Field Office, 

Connecticut River Coordinator's Office 

103 East Plumtree Road 

Sunderland, MA 01375 

E-234 

R. Ronald Gray 

640 Sterling Drive 

Red Lion, 17356 

Louis Grofton 

25 Quarry Road 


Mr. Dennis T. Guise 

2313 Forest Hills Drive 


Lisa Gutierrez 

580 Taylor Avenue E-4 


Mr. Dan Haas 

National Park Service - U.S. 

Department of Interior 

200 Chestnut St. 5 th floor 

Philadelphia, PA 19106 

Jim Hackett 

Lancaster County Parks Department 

1050 Rockford Road 


Mr. Lee Haile 

MSSA-Perry Hall Chapter 

President 

1511 A Providence Road 

Towson, MD 21286 

James W. Haines 


P.O. Box 1715 


Don Harmer 

39 Cynthia Ct 

Elkton, MD 21921 

Mr. Alex Haro Ph.D. 

U. S. Geological Survey, Biological 

Resources Discipline 

Research Ecologist 

S. O. Conte Anadromous Fish 

Research Laboratory 

1 Migratory Way, P.O. Box 796 

Turners Falls, MA 01376 

Danielle Haslup 

17 Wilson Road 

Rising Sun, MD 21011



Marjorie Heagy 

Harford Bird Club 

Treasurer 

1438 Sharon Acres Road 

Forest Hill, MD 21050 

Michael R. Helfrich 

Lower Susquehanna Riverkeeper 

324 W. Market Street 


Mr. Michael Hendricks 


Commission 

450 Robinson Lane 

Bellefonte, PA 16823 

Mr. Aaron Henning 




Ron Hentzier 

Lancaster News 

8 West King St 


Mr. Jere Hess 

507 Baron Road 

North East, MD 21901-2738 

Alice Hess 

1772 Rawlinsville Road 


Mr. Alexander R. Hoar 


300 Westgate Center Drive 

Hadley, MA 01035-9589 

Robert Hodge 

11 Elkside Farm Lane 

North East, MD 21901 

Jennifer Hoffman 




James Hooper 

Mason-Dixon Trail System 

President, M-DTS 

309 Bank Hill Road 


E-235 

Herman Hopman 

207 Dakota Avenue 

Wilmington, DE 19803 

James Horton 

ConowingoLake.com 

P.O. Box 407 

Whiteford, MD 21160 

Mr. Tom Horton 

Morning News & Baltimore Sun 

Calver and Center Streets 


Donovan J. Houck 



Environmental Planner 

Rachel Carson State Office Building 



Ms. Susan C. Hughes 

Pennsylvania Federation of 

Sportsmen's Clubs 

Director 

2426 North 2nd Street 


Mr. Gerit F. Hull 

Eckert Seamans Cherin & Mellott, 

LLC 

Attorney for Susquehanna River Basin 

Commission 

1747 Pennsylvania Avenue, N.W. 

Suite 1200 

Washington, D.C. 20006, D.C. 20006 

Mr. Chris Iverson 

1200 Nursery Road 


Mr. David Jostenski PE 

State of Pennsylvania 

Water Use Planning & Assessment, 

Bureau of Watershed Management 

P.O. Box 8555 




Jennifer Kagel 


Susquehanna River Coordinator 

(acting) 

308 Washington Avenue 

PO Box 75 


Mr. Franklin Keel 

U.S. Department of the Interior, 

Bureau of Indian Affairs 

545 Mariott Drive, Suite 700 

Nashville, TN 37214 

Sean Kenny 

York County Farm and Natural Lands 

Trust 

156 North George Street York, PA 

17401 

Anne Ketchum 



Executive Assistant 

P.O. Box 8767 


Tammy Klunk 

York County Dept. of Parks and 

Recreation 

Director 



Jim Kushlan 

405 Fairmont Rd 

Havertown, PA 19083 

David S. Ladd 




Mr. Michael J Langland 

U.S. Geological Survey 

Hydrologist 

215 Limekiln Road 

New Cumberland, PA 17070 

E-236 

Lynn Lankshear 



DOC/NOAA 



Louise Lawrence 

Maryland Department of Agriculture, 

Office of Resource Conservation 

Chief 

50 Harry S. Truman Parkway 


James Leigey 


Bureau of Land Management 



Ms Mary Anne Lisanti 

Lower Susquehanna Heritage 

Greenway Commission 

Executive Director 

4849 Conowingo Rd 


Mary Ann Lisanti-DELETE 

Lower Susquehanna Heritage 

Greenway, Inc. 


4948 Conowingo Road 


William G. Little 

New York State Department of 

Environmental Conservation 

Office of General Counsel Associate 

Counsel 

625 Broadway 

Albany, NY 12233-1500 

Ms. Erin Lynam 


Aquatic Ecologist, Water Resources 

Management 



Cheryl Mackley 

P.O. Box 5 

Holtwood, PA 17532



Jay Mackley 

P.O. Box 5 


Allyson McCollum 



Water Quality Specialist Supervisor 

Southcentral Regional Office 



Kristan McKinne 




Mr. Dan McLaughlin 

16 Spready Oak Road 

Rising Sun, MD 21911 

Mr. Douglas C. McLearen 

Pennsylvania Historical and Museum 

Commission Bureau for Historic 

Preservation 

Chief Division of Archaeology & 

Protection 

400 North Street 

Commonwealth Keystone Building, 

2nd Floor 


James J. McNulty 

Pennsylvania Public Utility 

Commission 

Acting Secretary 

Commonwealth Keystone Building 

400 North Street, 2nd Floor 


Mr. Wayne Melnick 


Commission 

Assistant Counsel 

PO Box 67000 


Glenn R. Melroy 


P.O. Box 2870 

Portland, OR 97208 

E-237 

Kevin Mendik 

National Park Service, Boston Support 

Office 

15 State Street 

Boston, MA 02109 

Honorable Barbara A. Mikulski 

United States Senate 

Washington, DC 20510 

Mike Millard 


Northeast Fishery Center 

P.O. Box 75 

308 Washington Ave. 


Anita Miller 

U.S. Department of Interior - Office of 

Environmental Policy and Compliance 

Philadephia Region 

Custom House, Room 244 


Jeremy Miller 





Larry Miller 


Project Leader 

Alleghany National Fish Hatchery 

6616 Hemlock Road 

Warren, PA 16365-8055 

Jeral A. Milton 

Legg Mason Tower 

111 South Calvert Street, Ste 2700 


Mr. Steve Minkkinen 

U.S. Fish and Wildlife Service, 


Project Leader 



Mr. Leopoldo Miranda 


Field Supervisor 

Chesapeake Bay Field Office



Tara Moberg 

The Nature Conservancy PAHBG 

Freshwater Scientist 

2101 N. Front St 

Suite 200 Building 1 


Olivia A. Mowery 

PA Game Commission, Bureau of 

Wildlife Habitat Management 

Division of Environmental Planning & 

Habitat Protection 



Joane D. Mueller 

Maryland Department of Environment 

MDE Clearinghouse Coordinator 

1800 Washington Boulevard 


Tracey Librandi Mumma 




Skip Newcomer 

P.O. Box 8228 

Lancaster, PA 

Debby Nizer 


Baltimore District, CENAB-OP-RPA 

P.O. Box 1715 


Mr. John Norbeck 



P.O. Box 8552 

Hamburg, PA 17105 

Janet Norman 


Fish and Wildlife Biologist 

Chesapeake Bay Field Office 177 

Admiral Cochrane Drive 


E-238 

Mr. John O'Shea 

Atlantic State Marine Fisheries 

Commission 

1050 N. Highland Street, Suite 200A- 

N 

Arlington, VA 22201 

Jason E. Oyler 


Commission 

Office of Chief Counsel 

P.O. Box 67000 

1601 Elmerton Ave 


Mr. Ian Park 





M. Dukes Pepper Jr. 



Office of Chief Counsel Assistant 

Counsel 



Mark Platts 

Lancaster York Heritage Region 

1706 Long Level Road 


Mr. David R. Poe 

Dewey & LeBoeuf, LLC 

Counsel for PPL Holtwood, LLC 

1101 New York Avenue, NW 

K Avenue, NW Suite 1100 

Washington, DC 20005-4213 

Mr. Frank Pownell 

1280 East Macton Road 

Street, MD 21154 

Mr. Don Pugh 


10 Old Stage Road 

Wendell, MA 01379 

Mr. Charles Ramsay 

3527 Level Road 

Churchville, MD 21028



Mary Ratnaswamy, PhD 


Program Supervisor, Threatened and 

Endangered Species 


Chesapeake Bay Field Office 


Stephanie Richardson 




Jim Richenderfer 




Mr. Ben Rizzo 


Engineering Consultant 

One Gateway Center -Suite 612 

Newton Corner, MA 02458 

Richard Roos-Collins 

Natural Heritage Institute 

100 Pine St., Ste. 1550 

San Francisco, CA 94111 

Mr. David Rosenstein 

Connectiv 

P.O. Box 6066 

Newark, DE 19714-6066 

Mr. Joe G. Rudy 

107 Arrowhead Circle 

Conestoga, PA 17516 

Mr. Paul Rudy 

1346 Fremont St 

Lancaster, PA 17603-6814 

Jeff Schmidt 

PO Box 84 

Millersville, MD 17551 

Timothy Schmidt 

1803 Orwig Ct 

New Freedom, PA 17349 

Steve Schreiner 

Versar Inc. 

9200 Rumsey Road 

Columbia, MD 21045 

E-239 

John Seebach 


Director, Hydropower Reform 

Initiative 

1101 14th St. NW, Suite 1400 


John Seitz 


Water Resources Coordinator 

28 East Market Street 

York, PA 17401-1580 

Pam Shellenberger 


Chief, Long Range Planning 


York, PA 17401-1580 

Mr. Tyler E. Shenk 

Susquehanna River Rasin Commission 

Water Quality Specialist 



Laurie E. Shepler 


Commission 

Office of Chief Counsel 

P.O. Box 67000 


Andrew Shiels 


Commission 

1735 Shiloh Road 


Ellen Shultzabarger 



(DCNR) 

Environmental Review Specialist 

P.O. Box 8552 

Hamburg, PA 17105 

Julie Slacum 




Annapolis, MD 21401



Topher Smith 

American Whitewater 

394 Butler Rd 

Reisterstown, MD 21136 

Mr. Tom Smith 

York Audubon Society 

President 

Mr. Geof Smith 

State of Pennsylvania 



Mr. Adam D. Snyder 

Office of the Attorney General 

Assistant Attorney General 

1800 Washington Blvd 

Suite 6048 


Aaron Sparks 

Pennsylvania Senate 

44 N. Christian St, Suite 100 


Mr Wayne Spilove 

Pennsylvania Historical and Museum 

Commission 


300 North Street 


James S. Spontak 



Southcentral Region Program Manager 



Mr. Andy St. John 

Pennsylvania Dept of Conservation 

and Natural Resources 

Park Manager 

6000 Mt.Pisgah Road 


Patricia Stabler 

Chester Water Authority 

100 Ashville Road 

Nottingham, PA 19362 

E-240 

Scott W. Standish 


Commission 

Director 

150 N. Queen Street, Suite 320 


Mr. Ronald Steelman 

3529 Green Spring Road 

Havre de Grace, MD 21078 

MR. Roger Stoner 

Lancaster County Bird Club 

Treasurer 

1650 Princess Anne Drive 


Donna & Kerry Stoudt 

1738 State Hill Rd 

Peach Bottom, PA 

Sara Strassman 

American Rivers, River Restoration 

Program 

Associate Director 

355 N. 21st Street, Suite 309 

Camp Hill, PA 17011 

David Sutherland 

U.S. Fish and Wildlife Service, CBFO 

Chair 



Linda Swank 



Harrisburg, Harrisburg, PA 17110- 

9797 

E. James Tabor 


Environmental Protection, Coastal 

Zone Management Office 

Chief 

P.O. Box 8555 


Mr. Gary L. Teadway 

1724 Beaver Valley Pike 

Strasburg, PA 17579



Julie Thompson 





Andrew Tittler 

U.S. Department of Interior 

Office of the Solicitor, Northeast 

Region -Attorney 

One Gateway Center, Suite 612 

Newton, MA 02458-2802 

Lawrence J. Toth 



Environmental Planner - Coastal 

Resources Mgmt Program 

P.O. Box 2063 

Rachel Carson State Office Bldg 


Charles Trees, III 

57 Cedar Acres Drive 


Jane Trout 

2344 Beaver Valley 

New Providence, PA 17560 

Mr. Joshua Tryninewski 


Commission 

Fisheries Biologist 

Anadromous Fish Restoration Unit 

1735 Shiloh Rd. 

State College, PA 16801, PA 16801 

Lisa H Tucker, Partner 

Kirkpatrick & Lockhart, Preston Gates 

Ellis, LLP 

1601 K Street, NW 


Alliance for Chesapeake Bay 

Maryland – Annapolis 

501 Sixth Street 


Chesapeake Bay Foundation 

6 Herndon Aveune 


E-241 

Lancaster County Parks & Recreation 



York County Parks & Recreation 




100 W. Market Street 


Lower Chanceford Township 



Peach Bottom Township 

545 Broad Street, Extended 





Drumore Township 

1675 Furniss Road 

P.O. Box 38 


Delaware Nation 

P.O. Box 825 

Anadarko, OK 73005 

Chesapeake Bay Critical Areas 

Commission (Maryland) 

1804 West Street, Suite 100 


Maryland Department of Natural 

Resources 

Tawes State Office Building 

580 Taylor Avenue 






Commission 

P.O. Box 67000 





Susquehanna River Coordinator 

P.O. Box 67000 





P.O. Box 8767 400 Market Street 


U.S. Environmental Protection 

Agency, Region III 

Section Chief 

1650 Arch Street 


County of Lancaster 

P.O. Box 83480 

Lancaster, PA 17608-3480 



DOC/NOAA 

Regional Director 

1 Blackburn Drive 

Gloucester, PA 01930-2237 



P.O. Box 2063 




Director 

P.O. Box 8460 





Pennsylvania Office of Attorney 

General 

16th Floor Strawberry Square 


U.S. Coast Guard, MSO Philadelphia 

1 Washington Avenue 


E-242 

Upper Chesapeake Watershed 

Association 

138 West Lanvale Street 


County of York, York County 

Courthouse 


York, PA 17401-1501 

Bureau of Land Management 

Eastern States Office 

7450 Boston Blvd 

Springfield, VA 22153 



Director 

P.O. Box 8551 




400 Waterfront Drive 

Pittsburgh, PA 15222-4739 



P.O. Box 8555 



Agriculture 

2301 N. Cameron Street 




P.O. Box 8647 


Pennsylvania Wildlife Federation, PA 

Federation of Sportsmen's Club, Inc. 

2426 North 2nd Street 


U.S. Coast Guard, MSO Pittsburgh 

1150 Kossman Bldg., 100 Forbes 

Avenue 

Pittsburgh, PA 15222-1371



U.S. Coast Guard, MSO Baltimore 

2401 Hawkins Point Road Bldg 70 


U.S. Bureau of Land Management 

Field Manager 

626 East Wisconsin Avenue Ste 200 

Milwaukee, WI 53202-4618 


Director 

P.O. Box 67000 



Commission 


Bellefonte, PA 16823-8133 

Pennsylvania Office of the Governor 

Governor 

225 Main Capitol 


U.S. Department of the Interior, 

Bureau of Indian Affairs 

1849 C Street, NW 



550 Main Street 

Cincinnati, OH 45202 


Commander 

26 Federal Plz # 2109 

Brooklyn, NY 10278 

Delaware River Basin Commission 


P.O. Box 7360 

West Trenton, NJ 08628-2404 

Safe Harbor Water Power Corporation 

1 Powerhouse Road 

Conestoga, PA 17516-9651 


Director 


P.O. Box 716 


E-243 

Christopher Urban 


Commission 

Chief - Natural Diversity Section 


Bellefonte, PA 16823-9620 

Pat Valdata 

Cecil Bird Club 

Treasurer 

36 Gina Court 

Leo Wallace 

Malone and Neubaum 

Attorney 

42 South Duke Street 


Larry Walter 

17 Dogwood Drive 

Conestoga, PA 17516 

Herbert H. Ward 

Upper Chesapeake Watershed 

Association 

138 West Lanvale Street 


Mr. Douglas Weaver 

York Haven LLC 

York Haven Hydro Station 

P.O Box 67 

York Haven, PA 17370 

Mr. Robert Weaver 


Agriculture 

Soil Conservationist 

NRCS, Lancaster Field Office 

1383 Arcadia Road, Room 200 


Susan Weaver 

State of Pennsylvania DEP 

P.O. Box 8647 


Elliott Weinstein 

P.O. Box 5005 

York, PA 17405



Paul Weiss 

Lancaster Dept. of Parks and 

Recreation 



Kurt Weist 

PennFuture 

Senior Attorney 

610 North Third St. 


R. Timothy Weston 

Kirkpatrick & Lockhart, Preston Gates 

Ellis, LLP 

17 North 2nd Street Floor 18 


Mr. John A. Whittaker, IV 

Winston & Strawn, LLP 

jwhittak@winston.com 

1700 K Street, NW 

Washington 

DC, 20006 

Sue Wiley 



Cynthia Wilkerson 

National Park Service 

US Customs House Stewardship and 

Partnership 

200 Chestnut Street 


Larry G. Williamson 



Office of the Secretary 




Larry Williamson 



P.O. Box 1554 


E-244 

Mr. Scott Williamson 



Southcentral Regional Office 



William T. Wisniewski 

U.S. Environmental Protection Agency 

- Region III 

Deputy Regional Administrator 

1650 Arch Street 


Vernie Wood, Jr. 

31 Crystal Drive 


Mark Woythal 

New York State Department of 

Environmental Conservation 

Division of Fish and Wildlife Marine 

Resources 

625 Broadway 

Albany, NY 12233 

Lori K. Yeich 



Natural Resource Program Supervisor 

David & Nancy Yohn 

Citizen/Landowner 

P.O. Box 658 


Andrew C. Zemba 



P.O. Box 2063 


Julie Zimmerman 

Nature Conservancy 

5410 Grosvenor Lane Suite 100 

Bethesda, MD 20814



APPENDIX A - RESPONSE TO COMMENTS RECEIVED ON DRAFT LICENSE 

APPLICATION 

E-245

� 

Exhibit E – Appendix A 

This appendix summarizes Exelon’s responses to the comment letters that were filed with FERC on the Muddy Run Project (Project No. 2355) Draft License 

Application (DLA). The appendix is divided into two sections. Section 1 provides Exelon’s detailed reply to the comment letters submitted to FERC. Section 2 

provides a copy of each comment letter, and includes highlighting and cross referencing to the comment response table for each comment which Exelon is 

providing a response. 

Cmnt 

No. 

Stakeholder 

1 FERC 

2 FERC 

3 FERC 

Date Comment Exelon’s Response 

In section 1.1 of Exhibit A (page A-2), you state that 

the crest of the main dam is at elevation 533 feet; 

however, in Exhibit G (sheet 2 of 4), the top of the 

dam is shown at elevation 530 feet. In the final 

application, please clarify this inconsistency. 

Section 4.51(b)(1) of the Commission’s regulations 

requires the physical composition, dimensions, and 

general configuration of any dams, spillways, 

penstocks, powerhouses, tailraces, or other 

structures, whether existing or proposed, to be 

included as part of the project. On page A-4, please 

provide a rating curve equation of the upper 

reservoir spillway. 

In section 2.2 of Exhibit B (pages B-4 and B-5), you 

describe flow conditions of the Susquehanna River 

and present annual and monthly flow duration 

information in a tabular format (table 2.2-2). In the 

final license application, please also provide 

monthly flow duration curves as required by section 

4.51(c) of the Commission’s regulations. 

Exhibit E - Appendix A - Page 1 

The crest of the main dam is at elevation 533 feet. This elevation has 

been consistently reflected in the various FLA exhibits. 

The rating curve equation has been provided on Figure 1.5-1 in Exhibit 

A of the FLA. 

Monthly flow duration curves have been added to Exhibit B-Section 2.2 

of the FLA.

Cmnt 

No. 

� 

Stakeholder 

4 FERC 


On page D-7, you stated that the on-peak and offpeak 

values were $53.04/ megawatt hour (MWh) 

and $37.45/MWh, respectively. Please provide a 

reference for these values and explain why these are 

different with the values of the Conowingo Project 

(on-peak value: $53.61/MWh and off-peak value: 

$37.39/MWh) within the Pennsylvania-New Jersey- 

Maryland (PJM) Interconnection, whose geographic 

area includes that of the Mid-Atlantic Area Council 

(MAAC) region. 


Generators within PJM get paid a Locational Marginal Price (LMP) 

value based on the generation bus LMP. LMP is the pricing mechanism 

for wholesale power in the PJM energy market. Each generator in 

PJM’s system has its own generator bus LMP value. 

An LMP is comprised of three price components: System Energy Price + 

Transmission Congestion Cost + Cost of Marginal Losses. Although 

Conowingo and Muddy Run are in located fairly close to each other in a 

physical sense, Conowingo and Muddy Run do not share the same 

generator bus LMP and are on different transmission circuits. The 

differences in their values are a result of their Transmission Congestion 

and Marginal Losses. 

Generating units are sent congestion price signals from PJM based on 

their impact on a constrained line. The interconnection point of the 

generator is important in indicating where its generation output flows on 

the transmission line. Both Conowingo and Muddy Run interconnect to 

PECO’s 230kV system, but have different impacts on different parts of 

the transmission system. Conowingo is connected to the Colora and 

Nottingham substations which are more closely connected to PECO’s 

southern 230 kV network. Muddy Run is connected to the Peach 

Bottom and Conchranville (Newlinville) substations which are more 

closely connected to PECO’s northern 230 kV network. Therefore, 

although these two generating faculties are in fairly close geographic 

area with one another, the difference in the electricity price signal each 

unit receives from PJM is largely based on where they connect to the 

transmission network. 

The electricity values referenced in Exhibit D were generated from an 

Exelon software application called VPT (Visual Presentation Tool). 

This application software retrieves PJM data such as LMP electricity 

prices from the PJM database. Exelon’s program retrieves data every 

hour and also on a daily and monthly basis. The data referenced in 

Exhibit D was the historical Real Time LMP values for Conowingo 

(Pnode #37401237) and Muddy Run (Pnode #734134) for 2011.

Cmnt 

No. 

� 

Stakeholder 

5 FERC 

6 FERC 

7 FERC 

8 FERC 


In section 2.1.1, you provide a brief description of 

the lands within the project boundary; however, you 

do not explain the location of the project boundary. 

In the final license application, please provide a 

narrative that includes the specific location of the 

project boundary, such as elevation, landmarks, etc. 

In section 3.3.2 (pages E-3-38 to E-3-42), you 

discuss water quality monitoring at the Muddy Run 

reservoir and at the tailrace, including temperature 

and dissolved oxygen conditions at those locations. 

Although you show the 2010 sampling locations in 

figure 3.3.2.1.2-1, you do not provide any maps 

showing the 2011 sampling locations. In your final 

license application, please provide a figure showing 

the 2011 sampling locations. 

In the final license application, so that we may 

adequately describe terrestrial resources for our 

environmental analysis, please provide: 1) acreage 

estimates for the upland habitat categories you 

describe in section 3.3.4, and 2) any additional 

information on the location and extent of invasive 

exotic species you observed within the project 

boundary (i.e., mile-a-minute, tree-of-heaven, 

autumn olive, bush honeysuckle, and Japanese 

stiltgrass). 

Please provide information on your standard 

transmission corridor maintenance methods, 

including: the methods you use to manage 

vegetation (i.e., mechanical, chemical, etc.), your 

typical maintenance schedule (i.e., activities 

performed annually, seasonally, as-needed, 

etc.), your procedures for managing vegetation in 

sensitive habitats (i.e., wetlands, riparian habitat, 

etc.), and your procedures when rare, threatened, or 

endangered plants or animals are encountered 

during routine maintenance. 


The location of the project boundary has been described in Exhibit B, 

Section 2.1.1 of the FLA. 

Figure 3.3.2.1.2-1 has been revised in Exhibit E of the FLA showing the 

2011 sampling locations. 

Acreage estimates have been included in Section 3.3.4. Where possible, 

additional information is provided on invasive species observed during 

field investigations. No comprehensive field surveys were conducted to 

determine the presence and/or extent of specific botanical resources or 

the respective plant community boundaries within the Project boundary. 

Exelon currently employs the Best Management Practice known as 

Integrated Vegetative Management for managing vegetation within the 

transmission line located in the Project boundary. Exhibit E, Section 

3.3.4 of the FLA has been updated to include this information.

Cmnt 

No. 

� 

Stakeholder 

9 FERC 

10 FERC 

11 FERC 


So that we may adequately describe littoral zone and 

riparian resources for our environmental analysis, 

please provide acreage estimates for littoral zone 

and riparian habitat within the project boundary in 

the final license application. 

In section 3.3.4.2, you provide a discussion of 

potential effects of project transmission lines on 

birds with specific information from Muddy Run 

study 3.7; however, you do not provide any 

evidence to support your discussion. For 

instance, you conclude that certain areas (water 

crossing) and line configurations (shield wires 

situated above conducting wires) pose a greater risk 

of collision and electrocution, respectively, to large 

raptors, but do not provide background information 

on why this is the case. In the final license 

application, please expand this section to provide 

supporting information. 

In section 3.3.4.1.7 (Wetland, Littoral, and Riparian 

Wildlife), you state that related “…aquatic resources 

are discussed in section 4.4;” however, there does 

not appear to be a section 4.4 in Exhibit E that 

addresses aquatic resources. In the final license 

application, please clarify where the related aquatic 

resources are discussed. 


The estimated extents of littoral and riparian zones are provided in 

Exhibit E, Sections 3.3.4.1.5 and 3.3.4.1.6, respectively, of the FLA. 

Exhibit E, Sections 3.3.4.1.9 and 3.3.4.2 of the FLA have been updated 

to provide the requested information. 

The DLA incorrectly identifies section 4.4 as related to aquatic 

resources. The correct section is 3.3.3. This has been corrected in the 

FLA.

Cmnt 

No. 

� 

Stakeholder 

12 FERC 

13 FERC 

14 FERC 

15 FERC 


In section 3.3.5, you note that two state-listed plants 

(reflexed flatsedge and umbrella magnolia) and one 

non-listed rare bird (prothonotary warbler) were 

reported by the Pennsylvania Department of 


(Pennsylvania DCNR) and the Pennsylvania Game 

Commission, respectively, as potentially occurring 

within the project area. In addition, your Preapplication 

Document states that three non-listed 

rare plants (cranefly orchid, eastern gamagrass, 

and netted chainfern) were reported by Pennsylvania 

DCNR as historically occurring in the project area. 

So that we may adequately describe potential effects 

on these species in our environmental analysis, in 

the final license application, please provide any 

observations you made of the above species, and an 

assessment of the likelihood of their occurrence 

within the project boundary. 

In section 3.3.5.4 (Proposed Environmental 

Measures), please provide the terms of your 

proposed Osprey Management Policy, as noted on 

page 6-4 of the Muddy Run Shoreline Management 

Plan. 

In section 5.4 (page E-5-2), you include the National 

Park Service’s Nationwide Rivers Inventory as a 

comprehensive plan applicable to the project; 

however, you list the 1982 plan. Please note that the 

most recent comprehensive plan for the National 

Park Service’s Nationwide Rivers Inventory on file 

with the Commission is dated 1993. 

The Exhibit G maps show an outline for the Muddy 

Run reservoir, as well as for the Susquehanna River; 

however, they do not indicate the elevation. In the 

final license application, please specify the 

elevations of the outlines for the reservoir and the 

river on the Exhibit G maps. 


Prothonotary warbler is not mentioned in Section 3.3.5, but was 

mentioned in the PAD. A species-specific survey was not conducted for 

prothonotary warbler. Although the general habitat for this bird is 

present in the project area, the species was not observed during any of 

the field studies. 

The species are added and discussed in Exhibit E, Section 3.3.5 of the 

FLA. Prothonotary warbler is not discussed in the DLA or FLA because 

more recent (2009) consultations with the Pennsylvania Game 

Commission did not indicate it to be a species of concern for the Project. 

The additional information requested regarding plants has been added to 

Exhibit E, Section 3.3.4 of the FLA. 

Exelon’s proposed measures to protect Osprey have been included in 

Exhibit E, Section 3.3.5.4 and the Muddy Run Shoreline Management 

Plan, included in Volume 3 of the FLA. 

Section 5.4 of the FLA provides a review of the 1993 Nationwide Rivers 

Inventory. 

The elevations of the reservoir and river have been included on the 

Exhibit G maps provided in Exhibit G of the FLA.

Cmnt 

No. 

� 

Stakeholder 

16 FERC 

17 FERC 

18 FERC 

19 FERC 


Section 4.44(h) of the Commission’s regulations 

requires that each sheet of Exhibit G must contain a 

minimum of three known reference points. In the 

final license application, please include a minimum 

of three known reference points on the Exhibit G 

maps. 

The Exhibit G maps included with the draft license 

application are in draft form and are not stamped by 

a registered land surveyor. In the final license 

application, please remember to provide final 

Exhibit G maps stamped by a registered land 

surveyor, as required by section 4.39 of the 

Commission’s regulations. 

The updated study reports for two terrestrial species 

you investigated for your license application at the 

request of resource agencies, black-crowned night 

heron (Conowingo 3.31) and rough green snake 

(Muddy Run 3.9B), indicate potentially suitable 

habitat for both species within the project 

boundaries, and historic nesting habitat for blackcrowned 

night-heron on Rowland Island. 

Please explain if there is a substantive difference 

between a “management plan” and a “management 

policy,” as you have described them in your SMPs. 

Also, as there appears to be suitable habitat within 

the project boundary for blackcrowned night-heron 

and rough green snake, reproducing populations of 

these two species could be detected within the 

project boundaries in the future. Therefore, please 

explain why you haven’t developed management 

plans or policies for black-crowned night-heron and 

rough green snake. 

The version of both SMPs submitted electronically 

as Volume 3 of the Draft License Application 

contains an incomplete set of figures. Only the first 

of four figures indicating the proposed project 

boundary is provided. 


The required three known reference points have been added to the 

Exhibit G maps provided in Exhibit G of the FLA. 

The Exhibit G maps provided in Exhibit G of the FLA have been 

stamped by a licensed surveyor. 

While not prioritizing the importance of separate endangered species, 

Exelon has focused efforts on species with specific management 

objectives which will benefit from specific actions outlined within a 

separate management plan. It was not our intent to prepare a 

management plan for each RTE species identified. 

A Management Plan is a set of proposed management activities 

documented through the development of a Management Plan. A 

management policy is a specific, individual management activity which 

will be observed by Exelon during the term of the next FERC license. 

Species specific management plans or policies for the night-heron and 

the rough green snake will be identified and developed through 

completion of Section 7 ESA consultation for these species, if it is 

determined that consultation is required. 

All four of the figures associated with the SMP have been included in 

the revised SMP submitted in Volume 3 of the FLA.

Cmnt 

No. 

� 

Stakeholder 

20 FERC 

21 FERC 

22 FERC 

23 FERC 


In section 4.3.1 (Monitoring Methods and 

Schedule), you propose to conduct bald eagle 

nesting surveys every 5 years, and to provide a letter 

of findings to the Pennsylvania Game Commission, 

Maryland Department of Natural Resources, and 

U.S. Fish and Wildlife Service in each survey year. 

In the final plan, please include the Commission on 

the list of agencies receiving communication on any 

bald eagle surveys and findings. 

In section 4.2 (Prevent Impacts to Bog Turtles or 

their Habitat), you state that the presence of 

potential mid-level predators (i.e., fox, raccoon) 

“should be monitored, initially on a qualitative 

basis, to determine whether they may be a 

significant problem that would need to be addressed 

further.” In the final plan, please elaborate on how 

and when this monitoring would occur, and who 

would make the final decision on conducting more 

intensive monitoring. 

In section 4.3 (Improve/Restore Bog Turtle Habitat), 

you make several recommendations on monitoring 

woody encroachment and invasive species (other 

than reed canary grass), involving annual 

monitoring and treatment as needed. In the final 

license application, please elaborate on who would 

conduct the monitoring, and who would determine if 

treatment was needed. 

In the final bog turtle management plan, for any 

activities that involve monitoring and possible 

control of predators, invasive species, and woody 

encroachment, we recommend that some form of 

documentation of monitoring and control activity is 

prepared and reported to interested agencies 

(including the Commission), in the year the action 

occurs. Please also include the Commission in the 

year 5 and 10 reporting on the status of bog turtle 

surveys, as noted in table 1. 


Section 4.3.1 of the Bald Eagle Management Plan (BEMP) is updated to 

include FERC on the list of agencies to receive survey results. The 

BEMP is included in the FLA. 

The Bog Turtle Management (BTMP) submitted with the FLA has been 

updated to address this comment. 


updated to address this comment. 


updated to address this comment.

Cmnt 

No. 

� 

Stakeholder 

24 RFD 

25 TNC 

26 NMFS 


The Rawlinsville Volunteer Fire Company requests 

an 'emergency boat access ramp" be constructed on 

Exelon property at the southern end of the facility 

along the Susquehanna River. No such ramp 

currently exists on that property or in the immediate 

vicinity. 

This conclusory statement does not satisfy Exelon’s 

obligation under 18 C.F.R. 5.18(b)(5)(ii)(F) to 

“[i]dentify relevant comprehensive plans and 

explain how and why the proposed project would, 

would not, or should not comply with such plans 

and a description of any relevant resource agency or 

Indian tribe determination regarding the consistency 

of the project with any such comprehensive plan.” 

(Emphasis added). We request that Exelon 

demonstrate the consistency of its specific 

protection, mitigation, and enhancement measures 

with the specific goals and objectives in the relevant 

comprehensive plans. 

The DLAs and any NEPA document developed 

for these projects should, at a minimum, consider 

the following effects of project operations on 

alewife and blueback herring: 

o Impingement and entrainment, including 

mortality; 

o Effects of the presence of the dam on upstream 

passage including delayed migration and an 

assessment of the effectiveness of the fish passage 

facilities at passing these species upstream; 

o Loss of prey or access to prey; and, 

o Any impacts to habitat or conditions that make 

the Susquehanna River unsuitable for alewife and 

river herring. 


Exelon has met with Rawlinsville Volunteer Fire Company, and 

discussed that the requested access point is within the Project boundary, 

but not on lands owned by Exelon. If Rawlinsville Volunteer Fire 

Company is able to acquire the rights to use this property, Exelon will 

assist the fire company with their efforts to establish this emergency 

access boat ramp. 

Exelon has included in the Exhibit E, Section 5.4 of the FLA an analysis 

of the consistency with proposed protection, mitigation, and 

enhancement measures with the specific goals and objectives in the 

relevant comprehensive plans. 

Exhibit E, Section 3.3.3 of the FLA has been modified to include the 

requested information and analysis for alewife and blueback herring.

Cmnt 

No. 

� 

Stakeholder 

27 PFBC 

28 PFBC 

29 PFBC 

30 SRBC 


On page E-5-1, Exelon lists comprehensive plans 

they have reviewed. We note that the “Migratory 

Fish Management and Restoration Plan for the 

Susquehanna River Basin” is not listed, even though 

it has been submitted to FERC for the official 

record. In addition, SRBC’s “Comprehensive Plan 

for the Water Resources of the Susquehanna River 

Basin” is also not listed. 

Table 1.4.1-1lists entities that filed comments on the 

Scoping Document. The Pennsylvania Fish and Boat 

Commission is not listed, despite the fact that we 

did file comments. 

On page 8-1 of the Recreation Plan, Exelon 

dismisses a proposed birding platform previously 

suggested by PFBC. We believe that such a platform 

would be used heavily, especially during the winter 

when large flocks of waterfowl are present at 

Muddy Run. Such a facility could be constructed at 

minimal cost. Please see the diagram below for a 

conceptual drawing. Existing fencing could be 

relocated at a lower elevation to maintain site 

security but permit viewing. There is ample room 

for parking at the site and the site is relatively flat. 

A more detailed discussion of specific 

hydrologic modeling efforts needed at the 

Conowingo project are presented in the DLA review 

comments dated July 9, 2012, and recently 

submitted to FERC by SRBC for the Conowingo 

project (FERC Project No. 405). As stated above, 

SRBC believes it is of critical importance to 

identify, run, and evaluate various alternative 

operating scenarios, in consultation with the 

resource agencies and stakeholders, to determine 

potential impacts to the aquatic ecosystem and to 

other water users. 


The Comprehensive Plan for the Water Resources of the Susquehanna 

River Basin has been reviewed and included in the list of 

Comprehensive Plans in the FLA. The Migratory Fish Management and 

Restoration Plan for the Susquehanna River Basin is not currently listed 

as a comprehensive plan by FERC in their April 2012 list of plans. 

Table 1.4.1-1 of the FLA has been revised to reflect the fact that the 

Pennsylvania Fish and Boat Commission filed comments on the Pre- 

Application Document and Scoping Document. 

Exelon is committing to work with the PFBC to incorporate their 

requests, where feasible. Due to the fact that the recreation studies did 

not identify this improvement as a high priority for existing 

recreationalists, Exelon has not included this request in the FLA. 

Exelon has completed three of the requested alternative modeling 

scenarios and has included the model runs in Study Plan 3.11, which is 

filed with the FLA. Six additional model runs are being completed as 

requested, however due to SRBC requests for revisions to these model 

runs, Exelon does not have the time to complete the model runs and 

include them in the FLA.

Cmnt 

No. 

� 

Stakeholder 

31 USFWS 


Based on the American eel pumping entrainment 

rate of 26.3% at Muddy Run and juvenile American 

shad pumping entrainment rate of 22.6%, if instream 

collection techniques are found ineffective at 

capturing silver eels for downstream trap and 

transport, 3/4 inch bar racks, a guidance system, or 

other physical or behavioral barrier may be 

necessary for safe passage downstream. 


A pumping entrainment rate of 26.3% was estimated for telemetered eels 

that encountered the zone of influence at the Muddy Run Project during 

pumping mode. When this pumping entrainment rate is integrated into a 

model that includes the proportion of eels migrating when Muddy Run is 

typically pumping (from 2200 to and including 0500 hrs), the percentage 

of eels present near the intake structure, it is estimated that 

approximately 7% of the emigrating eels are likely to be entrained. 

A pumping entrainment rate of 22.6% was estimated for telemetered 

shad that encountered the zone of influence at Muddy Run during 

pumping mode. When the pumping entrainment rate is integrated to 

account for both the typical pumping schedule at Muddy Run and the 

known behavioral emigration pattern of juvenile American shad (peak 

emigration times between 1700-2200 hrs), it is estimated that 

approximately 2.9% to 6.6% of emigrating shad are likely entrained.

OFFICE OF ENERGY PROJECTS 

July 2, 2012 

Ms. Colleen Hicks 




FEDERAL ENERGY REGULATORY COMMISSION 

WASHINGTON, DC 20426 

RE: Comments on Draft License Applications 

Dear Ms. Hicks: 

Project No. 405-087 - Maryland/Pennsylvania 

Conowingo Hydroelectric Project 

Project No. 2355-011 – Pennsylvania 

Muddy Run Pumped Storage Project 


Pursuant ursuant to 18 CFR § 5.16(e), this letter contains Commission staff’s comments 

on your April 3, 2012 draft license applications for the Conowingo Hydroelectric Hydroel ctric Project 

and the Muddy Run Pumped Storage Project. Our specific comments on the applications 

are outlined in Appendix A. 

In several places throughout the draft license applications, you indicate that 

additional information would be provided regarding final/additional study results. 

Specifically, you are in the process of completing four studies: 

Conowingo 3.4 - American Shad Passage Study; Conowingo 3.5 - Upstream Fish Passage 

Effectiveness Study; Conowingo 3.19 - Freshwater Mussel Characterization Study below 

Conowingo Dam; and Conowingo 3.21 - Impact of Plant Operations on Migratory Fish 

Reproduction. Pursuant to § 5.22 of the Commission’s regulations, the Commission may 

find that the application is not ready for environmental analysis until the results of all 

studies are filed. We expect that these studies will be completed and filed consistent with 

the schedule outlined in the Conowingo Project’s draft license application. In addition, 

please ensure that the affected environment sections for resource include an appropriate 

description of the existing environmental condition at the projects, even if you are not 

proposing any changes that will affect the resource.

Project No. 405-087 

Project No. 2355-011 

If you have any questions regarding this letter or the contents of your final license 

applications, please contact Emily Carter at (202) 502-6512, or via email at 

emily.carter@ferc.gov. 

cc: Mailing List 

Public Files 

2 

Sincerely, 

Enclosures: 

Appendix A – Comments on the Draft License Applications 

John B. Smith, Chief 

Mid-Atlantic Branch 

Division of Hydropower Licensing

Appendix A 

Comments on the Draft License Applications 

Based on your draft license applications (DLA), we have identified that your final 

license applications (FLA) will require additional information and clarification regarding 

your licensing proposals. In our comments, we note the areas of each DLA where 

additional information will be needed for Commission staff to conduct its required 

environmental analysis. 

CONOWINGO HYDROELECTRIC PROJECT NO. 405 

Exhibit A – Project Description 

1. In section 1.0 (pages A-2 or A-3), you do not provide the dimensions of the ogee 

spillway. Section 4.51(b)(1) of the Commission’s regulations requires the 

physical composition, dimensions, and general configuration of any dams, 

spillways, penstocks, powerhouses, tailraces, or other structures, whether 

existing or proposed, to be included as part of the project. In the final license 

application, please provide this information. 

2. In section 1.1 (page A-2), you state that the total length of the dam is 4,648 feet. 

You also provide specific lengths of different sections of the dam; however, 

these specific lengths add up to be less than the provided 4,648-foot total length. 

In addition, the total length of the dam and the length of the powerhouse 

presented in Exhibit F (drawing F-2) differ from what you provided in Exhibit A. 

In the final license application, please correct these inconsistencies. 

3. In table 1.4-1 (pages A-3 and A-4), you provide intake structure characteristics 

for turbine units 1 through 7, including the intake area, width, and elevations. 

You also discuss butterfly valves, head gates, and stop logs at the intakes and 

how they are operated. You do not, however, provide any such information for 

the turbine units 8 through 11. In the final license application, please provide 

similar information for the intake structures for these units. 

4. Exhibit E includes various discussions related to the Conowingo dam tailrace; 

however, you do not provide any description of the project tailrace in Exhibit A. 

Please include a description of the tailrace in Exhibit A of the final license 

application.



MUDDY RUN PUMPED STORAGE PROJECT NO. 2355 

Additional Information Requests 

Exhibit A – Project Description 

6 

1. In section 1.1 of Exhibit A (page A-2), you state that the crest of the main dam is 

at elevation 533 feet; however, in Exhibit G (sheet 2 of 4), the top of the dam is 

shown at elevation 530 feet. In the final application, please clarify this 

inconsistency. 

2. Section 4.51(b)(1) of the Commission’s regulations requires the physical 

composition, dimensions, and general configuration of any dams, spillways, 

penstocks, powerhouses, tailraces, or other structures, whether existing or 

proposed, to be included as part of the project. On page A-4, please provide a 

rating curve equation of the upper reservoir spillway. 

Exhibit B – Project Operation and Resource Utilization 

3. In section 2.2 of Exhibit B (pages B-4 and B-5), you describe flow conditions of 

the Susquehanna River and present annual and monthly flow duration 

information in a tabular format (table 2.2-2). In the final license application, 

please also provide monthly flow duration curves as required by section 4.51(c) 

of the Commission’s regulations. 

Exhibit D – Statement of Costs and Financing 

4. Section 4.51(e)(8) of the Commission’s regulations requires the on-peak and offpeak 

values of project power, and the basis for estimating the values, for projects 

which are proposed to operate in a mode other that run-of-river. On page D-7, 

you stated that the on-peak and off-peak values were 

$53.04/ megawatt hour (MWh) and $37.45/MWh, respectively. Please provide a 

reference for these values and explain why these are different with the values of 

the Conowingo Project (on-peak value: $53.61/MWh and off-peak value: 

$37.39/MWh) within the Pennsylvania-New Jersey-Maryland (PJM) 

Interconnection, whose geographic area includes that of the Mid-Atlantic Area 

Council (MAAC) region. 

Exhibit E – Environmental Report 

Existing Project Facilities 

5. In section 2.1.1, you provide a brief description of the lands within the project 

boundary; however, you do not explain the location of the project boundary. In 

5 

3 

1 

2 

4



7 

the final license application, please provide a narrative that includes the specific 

location of the project boundary, such as elevation, landmarks, etc. 

Water Resources 

6. In section 3.3.2 (pages E-3-38 to E-3-42), you discuss water quality monitoring 

at the Muddy Run reservoir and at the tailrace, including temperature and 

dissolved oxygen conditions at those locations. Although you show the 2010 

sampling locations in figure 3.3.2.1.2-1, you do not provide any maps showing 

the 2011 sampling locations. In your final license application, please provide a 

figure showing the 2011 sampling locations. 

Terrestrial Resources 

7. In section 3.3.4, you describe terrestrial communities within the project boundary 

(including upland forest, agricultural cropland, maintained lawns) in very general 

terms. In the final license application, so that we may adequately describe 

terrestrial resources for our environmental analysis, please provide: 1) acreage 

estimates for the upland habitat categories you describe in section 3.3.4, and 2) 

any additional information on the location and extent of invasive exotic species 

you observed within the project boundary (i.e., mile-a-minute, tree-of-heaven, 

autumn olive, bush honeysuckle, and Japanese stiltgrass). 

8. In section 3.3.4, you describe the presence of various upland habitats (both 

human-modified and natural) and forested and palustrine emergent wetlands 

within the transmission line corridor. Please provide information on your 8 

standard transmission corridor maintenance methods, including: the methods 

you use to manage vegetation (i.e., mechanical, chemical, etc.), your typical 

maintenance schedule (i.e., activities performed annually, seasonally, as-needed, 

etc.), your procedures for managing vegetation in sensitive habitats (i.e., 

wetlands, riparian habitat, etc.), and your procedures when rare, threatened, or 

endangered plants or animals are encountered during routine maintenance. 

9. In sections 3.3.4.1.5 (Littoral Zone Habitat and Vegetation) and 3.3.4.1.6 

(Riparian Zone Habitat and Vegetation), you describe the presence of vegetation 

within the littoral zone (i.e., water willow) and allude to the presence of riparian 

habitat. So that we may adequately describe littoral zone and riparian resources 

for our environmental analysis, please provide acreage estimates for littoral zone 

and riparian habitat within the project boundary in the final license application. 

10. In section 3.3.4.2, you provide a discussion of potential effects of project 

transmission lines on birds with specific information from Muddy Run study 3.7; 

however, you do not provide any evidence to support your discussion. For 

instance, you conclude that certain areas (water crossing) and line configurations 

9 

7 

10 

6



8 

(shield wires situated above conducting wires) pose a greater risk of collision and 

electrocution, respectively, to large raptors, but do not provide background 

information on why this is the case. In the final license application, please 

expand this section to provide supporting information. 

11. In section 3.3.4.1.7 (Wetland, Littoral, and Riparian Wildlife), you state that 

related “…aquatic resources are discussed in section 4.4;” however, there does 

not appear to be a section 4.4 in Exhibit E that addresses aquatic resources. In 

the final license application, please clarify where the related aquatic resources are 

discussed. 

Threatened and Endangered Species 

12. In section 3.3.5, you note that two state-listed plants (reflexed flatsedge and 

umbrella magnolia) and one non-listed rare bird (prothonotary warbler) were 

reported by the Pennsylvania Department of Conservation and Natural Resources 

(Pennsylvania DCNR) and the Pennsylvania Game Commission, respectively, as 

potentially occurring within the project area. In addition, your Pre-application 

Document states that three non-listed rare plants (cranefly orchid, eastern gama- 

grass, and netted chainfern) were reported by Pennsylvania DCNR as historically 

occurring in the project area. So that we may adequately describe potential 

effects on these species in our environmental analysis, in the final license 

application, please provide any observations you made of the above species, and 

an assessment of the likelihood of their occurrence within the project boundary. 

13. In section 3.3.5.4 (Proposed Environmental Measures), please provide the terms 

of your proposed Osprey Management Policy, as noted on page 6-4 of the 

Muddy Run Shoreline Management Plan. 

Consistency with Comprehensive Plans 

14. In section 5.4 (page E-5-2), you include the National Park Service’s Nationwide 

Rivers Inventory as a comprehensive plan applicable to the project; however, you 

list the 1982 plan. Please note that the most recent comprehensive plan for the 

National Park Service’s Nationwide Rivers Inventory on file with the 

Commission is dated 1993. 

Exhibit G – Project Boundary Maps 

15. The Exhibit G maps show an outline for the Muddy Run reservoir, as well as for 

the Susquehanna River; however, they do not indicate the elevation. In the final 

license application, please specify the elevations of the outlines for the reservoir 

and the river on the Exhibit G maps. 

11 

12 

13 

15 

14



9 

16. Section 4.44(h) of the Commission’s regulations requires that each sheet of 

Exhibit G must contain a minimum of three known reference points. In the final 16 

license application, please include a minimum of three known reference points 

on the Exhibit G maps. 

17. The Exhibit G maps included with the draft license application are in draft form 

and are not stamped by a registered land surveyor. In the final license 

application, please remember to provide final Exhibit G maps stamped by a 

registered land surveyor, as required by section 4.39 of the Commission’s 

regulations. 

Management Plans 


18. In your January 23, 2012, Shoreline Management Plans (SMPs) for the 

Conowingo and Muddy Run projects, you provide brief summaries of your 

proposed Bald Eagle (both SMPs) and Bog Turtle (Muddy Run SMP only) 

Management Plans, and your proposed Osprey Management Policy (both SMPs). 

The updated study reports for two terrestrial species you investigated for your 

license application at the request of resource agencies, black-crowned nightheron 

(Conowingo 3.31) and rough green snake (Muddy Run 3.9B), indicate 

potentially suitable habitat for both species within the project boundaries, and 

historic nesting habitat for black-crowned night-heron on Rowland Island. 

Please explain if there is a substantive difference between a “management plan” 

and a “management policy,” as you have described them in your SMPs. Also, as 

there appears to be suitable habitat within the project boundary for blackcrowned 

night-heron and rough green snake, reproducing populations of these 

two species could be detected within the project boundaries in the future. 

Therefore, please explain why you haven’t developed management plans or 

policies for black-crowned night-heron and rough green snake. 

19. The version of both SMPs submitted electronically as Volume 3 of the Draft 

License Application contains an incomplete set of figures. Only the first of four 

figures indicating the proposed project boundary is provided. 

Conowingo/Muddy Run Bald Eagle Management Plans 

20. In section 4.3.1 (Monitoring Methods and Schedule), you propose to conduct 

bald eagle nesting surveys every 5 years, and to provide a letter of findings to the 

Pennsylvania Game Commission, Maryland Department of Natural Resources, 

and U.S. Fish and Wildlife Service in each survey year. In the final plan, please 

include the Commission on the list of agencies receiving communication on any 

bald eagle surveys and findings. 

17 

18 

19 

20



10 

21. In section 4.2 (Prevent Impacts to Bog Turtles or their Habitat), you state that the 

presence of potential mid-level predators (i.e., fox, raccoon) “should be 

monitored, initially on a qualitative basis, to determine whether they may be a 21 

significant problem that would need to be addressed further.” In the final plan, 

please elaborate on how and when this monitoring would occur, and who would 

make the final decision on conducting more intensive monitoring. 

22. In section 4.3 (Improve/Restore Bog Turtle Habitat), you make several 

recommendations on monitoring woody encroachment and invasive species 

(other than reed canary grass), involving annual monitoring and treatment as 

needed. In the final license application, please elaborate on who would conduct 

the monitoring, and who would determine if treatment was needed. 

23. In the final bog turtle management plan, for any activities that involve 

monitoring and possible control of predators, invasive species, and woody 23 

encroachment, we recommend that some form of documentation of monitoring 

and control activity is prepared and reported to interested agencies (including the 

Commission), in the year the action occurs. Please also include the Commission 

in the year 5 and 10 reporting on the status of bog turtle surveys, as noted in 

table 1. 

22

FEDERAL ENERGY REGULATORY COMMISSION 

WASHINGTON, DC 20426 

OFFICE OF ENERGY PROJECTS Project No. 405-087 - Maryland/Pennsylvania 

Conowingo Hydroelectric Project 

July 3, 2012 

Project No. 2355-011 – Pennsylvania 

Muddy Run Pumped Storage Project 

Ms. Colleen Hicks 





RE: Errata to Comments on Draft License Applications 

Dear Ms. Hicks: 

The list of ongoing studies referenced in the second paragraph of our July 2, 2012 

cover letter providing comments on the draft license applications for the Conowingo and 

Muddy Run projects was incorrect. The second paragraph of that letter should read as 

follows: 

“In several places throughout the draft license applications, you indicate that 

additional information will be provided regarding final/additional study results. 

Specifically, you are in the process of completing four required studies: 

Conowingo 3.2 – Adult Shad Turbine Mortality Study; Conowingo 3.5 – Upstream Fish 

Passage Effectiveness Study; Conowingo 3.19 – Freshwater Mussel Characterization 

Study below Conowingo Dam; and Conowingo 3.21 – Impact of Plant Operations on 

Migratory Fish Reproduction. Pursuant to § 5.22 of the Commission’s regulations, the 

Commission may find that the application is not ready for environmental analysis until 

the results of all studies are filed. We expect that these studies will be completed and 

filed consistent with the schedule outlined in the Conowingo Project’s draft license 

application. In addition, please ensure that the affected environment sections for each 

resource include an appropriate description of the existing environmental condition at the 

projects, even if you are not proposing any changes that will affect the resource.”



If you have any questions regarding this letter, please contact Emily Carter at 

(202) 502-6512, or via email at emily.carter@ferc.gov. 

cc: Mailing List 

Public Files 

2 

Sincerely, 

Emily Carter, Project Coordinator 

Mid-Atlantic Branch 

Division of Hydropower Licensing

Re: Comments by The Nature Conservancy on the Draft License Applications for 

Conowingo and Muddy Run Projects (P-405 and P-2355) 

I. Description of The Nature Conservancy 

The Nature Conservancy’s Comments on Draft License Applications 

Exelon’s Conowingo and Muddy Run Projects (P-405 and P-2355)

II. General Comments 

A. Delayed Studies and Need for Completeness 


Exelon’s Conowingo and Muddy Run Projects (P-405 and P-2355) 

See

No. List of Incomplete Studies 

(or studies with comments still due) 

(submitted 

3/31/11; juvenile entrainment study 

submitted 1/24/12; adult 

entrainment study conducted spring 

2012) 

(report model development and 

input variables submitted 1/24/12) 

(telemetry study conducted 

Spring 2012) 

(addendum filed 1/24/12 on 

revised statistical analysis) 

(redlined 

revision submitted to address 2011 

comments 1/2412) 

(submitted 

4/29/11 and 6/2/11; baseline model 

analysis 1/24/12) 



Id 

Complete Remaining 

Study 

Element 

Comments

B. Need for Environmental Impact Statement 

See 



Id.

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