ML19064B232

Materials Prepared for the Environmental Protection Agency, Section 316(a) Demonstration for PBAPS Units No. 2 & 3 on Conowingo Pond - Part 1 of 2

ML19064B232
Person / Time
Site:	Peach Bottom
Issue date:	07/31/1975
From:	Exelon Generation Co, Philadelphia Electric Co
To:	Office of Nuclear Reactor Regulation, Environmental Protection Agency
Hayes B, NRR-DMLR 415-7442
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PEACH BOTTOM ATOMIC POWER STATION Materials Prepared For The Environmental Protection Agency 3*15 (a) Demonstration for PBAPS Units No. 2 & 3 on Conowingo Pond Prepared By PHILADELPHIA ELECTRIC COMPANY July 1975

ACKNOWLEDGMENTS All biological sections of this documen~ were prepared for the Philadelphia Electric company by Ichthyological Associates, Inc., Edward c. Raney, Ph.D., Director.

The biological basis for this document was provided by Edward c. Raney, Ph.D.,

Timothy w.

Robbins, Ph.D., Dilip Mathur, Ph.D., and associates.

Philadelphia Electric Company personnel who have assisted in many ways include Darryl J.

Bishop, John R.

Boyda, David R.

Helwig, Barry L. Hinkle, Edmund J. Purdy, Walter E. Rosengarten, Jr., Dale A. Wennagel and George M. Zaimis.

The following biologists also participated in the study in 1974:

Thomas M.

Alcoze, Diane

Amuso, Richard K.

Browell, Dennis G.

Buchanan, JeffreY~-E ---Dietz, _ ~---E. Terry -

Euston, Christopher R.

Frese, E. George

Groff, Robert T.

Gromelski, Pauline L. Heisey, Eric I. Illjes, Diane J.

Johnson, Ernest R.

Holmstrom, Jr.,

Lawrence L.

Jackson, Joanne M. Johns, Brian R.

Mccreight, Nancy c. Magnusson, Robert w.

• Malick, Jr.,

George T.

Mimidis, George A. Nardacci, Thomas F. Rosage, Bryan J. Simmons, James H.

Smith, Joanne M.

Tribble, Michael J.

Weik, Hugh E.

Wenger.

Others who have assisted in the field and laboratory include:

Barbara J.

Ankrim, Raymond E.

Arms, Margaret A.

Eckma"""

Arthur Ford, Sidney N. Graver, Janet A. Hacken, Sandra H.

Hube.

Allan c.

Kirch, Margaret A. Lehman, Joan L. Martin, Edna Marvei, Betty J. Mason, Ethel M. Nicodemus, Robert Reinhart, Sandra J.

Unruh and Lucie E. Wallace.

iii

SUMMARY

This document presents the technical information in support of Philadelphia Electric Company's (hereafter "Company")

request pursuant to Section 316(a) of the Federal Water Pollution Control Act for alternative thermal effluent limitations for its Peach Bottom Atomic Power Station (hereafter "PBAPS") which is located on Conowingo

Pond, a

run of the river impoundment on the Susquehanna River.

As detailed herein, on the basis of over 175 man-years of effort carried on by Ichthyological Associates on behalf of the Company by approximately 125 biologists, chemists and other specialists (including 29 full-time scientists and support personnel who are presently working on the studies),

the Company has concluded that the operation of PBAPS with the present cooling system (open cycle cooling with three helper towers to cool approximately half of the condenser effluent prior to discharge to the Pond) will assure the protection and propagation of a balanced indigenous, community of shellfish, fish and wildlife in and on the

~onowingo Pond.

Other alternatives are presented, the construction of two additional helper towers, and the construction of a

return channel in conjunction with the two additional

towers, allowing the discharge of heat to the Pond to be variable (the variable cycle cooling system)

• The Conowingo Pond has been under study by the company's consultant, Ichthyological Associates, since 1966 to determine baseline ecological conditions, which included determination of water quality and the species composition, distribution and fluctuations in abundance of the biota prior to the operation of PBAPS.

This report contains the results of per~inent experimental studies conducted to determine the swimming speed of fishes and the thermal preference, avoidance as well as effects of sudden decrease and increase in temperature on fishes; results of pertinent experimental work and literature searches regarding the selected representative species; engineering data concerning the various alternative cooling systems; and predic~ions of the isotherms for various river flow and meteorological conditions.

The limnological and fishery studies in the Pond are based on a large number of collections (over 16,000).

Baseline conditions are derived from the data from monitoring stations which have existed from the initial sampling date to the present.

Data collected from the preoperational program have been compared to those collected from the postoperational program.

No deleterious effects have been observed and no deleterious effects are predicted on the abundance and distribution of the biota in the Pond.

v

1. 0

1. 1

1. 2

1. 2. 1 1.2.1.1 1.2.1.2

1. 3

,

• 4

1. 5

1. 6

1. 7 1

• 7. 1 1.7.2

1. 7. 3

1. 7. 4 1.7.5

1. 7. 6 1.7.7

1. 8 1.9

1. 10 2.0 2.2

2. 2. 1 2.2.2 2.2.3 2.2.4 2.3

2. 3. 1 2.3.2 3.0 TABLE OF CONTENTS ACKNOWLEDGEMENI'S SUZ4.a.~RY * * * *

• INTRODUCTION. *

• JUSTIFICATION FOR THE CONCLUSION THAT THE PRESENT COOLING SYSTEM AT PEACH BOTTOM ATOMIC POWER STATION IS SUFFICIENT TO ASSURE THE PROTECTION AND PROPAGATION OF A BALANCED, INDIGENOUS COMMUNITY IN CONOWINGO POND. * *

• EXPECTED EFFECTS OF OPERATION OF THE PEACH BOTTOM ATOMIC POWER STATION UNITS NO. 2 AND NO. 3 * * * * * * * *.

• Water Temperature * *. *

• Natural water Temperature * * * *. * *..

Model Predictions of "Worst Case" Water Temperature Conditions. * * * * * * * * *

• DISSOLVED OXYGEN AND WATER CHEMISTRY.****

PHYTOPLANKTON COMMUNITY * * *

• ZOOPLANKTON COMMUNITY BENTHIC COMMUNITY * * * * * *

• FISHES. *. *. * *. * * *. * *.

Introduction. * * * * *.

Temperature Requirement of Fishes * * * *

• Fishes and Heated Plumes.

Reproduction. * * * * *

• Growth Food Habits * * * * * *

• Movement of Fishes ****

TROPICAL STORM AGNES ****

PREDICTED WINTER FISHERY *.

CONCLUSIONS * * * * * * * * * * * * * * * *

• PLANT OPERATING DATA.

UNIT LOADING.

Intake.

cooling * *

• Outfall * *

• Transit Times

• CHEMICAL AND WATER QUALITY DATA

• Chlorine ****

Other Chemicals * * * * * * *

• PLANT OPERATIONAL EXPERIENCE TO DATE.

• vii iii v

1-1 1-10 1-14 1-14 1-14 1-14 1-15 1-16 1-17 1-17 1-18 1-~

1-1-20 1-21 1-22 1-22 1-23 1-24 1-24 1-26 2-1 2-1 2-1 2-2 2-2 2-3 2-15 2-15 2-15 3-1

3. 1 3.2 4.0 4.1 4.2 4.3 4.4 4.5 5.0 6.0 6.1 6.2 6.3 6.4 7.0 7.1.0

7. 1. 1

7. 1. 2 7.1.2.1 7.1.2.2 7.1.2.3 7.1.2.4 7.1.2.5 7.1.2.6

7. 1. 3 7.1.3.1 7.1.3.2 7.1.3.3 7.1.3.4

7. 1. 4 7.1.4.1 7.1.4.2 7.1.4.3

7. 1. 5 7.1.5.1 7.1.5.2 7.1.5.3 7.1.5.4 7.1.5.5 7.2.0

7. 2. 1 7.'L.2 7.2.2.1 GENERATION & SHUTDOWNS.. * *

• BIOLOGICAL EFFECTS OF SHUTDOWNS

• SUSQUEHANNA RIVER HYDROLOGY RIVER FLOW.****

WATER TEMPERATURES.

CURRENTS. *. *..

DEPTH CONTOURS. * *

• FLOW TEMPERATURE RELATIONSHIPS.

METEOROLOGY * * * * * * * * *.

THERMAJ~ PLUME CHAR~CTERISTICS

• Predicted Isotherms *. *

• Observed Isotherms **.****

Plume Velocity Distribution Other Thermal Effluents * *. *.

AQUATIC COMMUNITY DESCRIPTION.

LIMNOLOGY OF CONOWINGO POND INTRODUCTION WATER QUALITY. *

• Temperature * * *

• Light Penetration Oxygen Biochemical Oxygen Demand * *. * *

• Chemical Parameters.

statistical Analysis..

PHYTOPLANKTON COMMUNITY.. * *

• Species composition *.

Plant Pigments *.*...

Statistical Analysis.

Aquatic Vascular Plants ZOOPLANKTON COMMUNITY

• Species Composition

• Abundance * *... *

• Statistical Analysis.

BENTHOS * * * *.. *. * * *. *

• Species composition.

Species Diversity and Equitability.

Distribution and Abundance.

Faunal similarity Biomass ABUNDANCE AND DISTRIBUTION OF FISHES *.

INTRODUCTION. * *..

SPECIES COMPOSITION Distribution. *. * *.

• vi ii 3-1 3-1 4-1 4-1 4-2 4-2 4-2

~-2 5-1 6-1 6-1 6-1 6-1 6-2

7. 1-1 7.1-1 7., -1

7. 1-1

7. 1-1

7. 1-1

7. 1-2

7. 1-2

7. 1-3

7. 1-3 7.1-13

7. 1-13 7.1-13 7.1-14

7. 1-15

7. 1-2 9 7.1-29 7.1-29

7. 1-2 9

7. 1-43

7. 1-43 7.1-43 7.1-45

7. 1-46 7

• 1-4 6 7.2-1

7. 2-1 7.2-1 7.2-2

7.2.2.2 7.2.3 7.2.3.1 7.2.3.2 7.3.0

7. 3.,

7.3.1.1 7.3.1.2 7.3.1.3 7.3.1.4 7.3.1.5 7.3.2 7.3.2.1 7.3.2.2 7.3.2.3 7.3.2.4 7.3.3 7.3.3.1 7.3.3.2 7.3.3.3 7.3.4 7.3.4.1 7.3.4.2 7.3.4.3

7. 3. 5 7.3.5.1 7.3.6 7.3.6.1 7.3.7 7.3.7.1 7.3.7.2 7.3.7.3 7.3.8 7.3.8.1 7.3.8.2 7.3.8.3 7.3.9 7.3.9.1 7.3.9.2 7.3.9.3 7.3.10 7.3.10.1 7.3.10.2 7.3.11 7.3.12 Abundance * * * *

• FISHES IN THE THERMAL Trap Net Catches.

Trawl Catches * *

• PLUME BIOLOGY OF FISHES * * * *

• WHITE CRAPPIE

(~QmQ~is ~nn~!~~b§)

Food Habits * * * * * * * * * *

• Reproduction. * * * * *

• Age and Growth. * * * * * * * *

• Year Class Fluctuations * * *

• Survival Rates. * * * * * * *

• CHANNEL CATFISH

(!~2l~~Y2 Q:!:!!:!~~!:Y§) * * *

• Food Habits * * * * * *

• Reproduction. * * * * * * *

• Age and Growth. * * * * * * * * * * * * *

• Year Class Fluctuations * * * * * *

• BLUEGILL (&g}?Qm!§ M~£fOChi!Y§ * * * *

• Food Habits * * * * * * * *

• Reproduction. * * * * * * * * * * *

• Age and Growth. * * * * * * * * * * * * *

• SPOTFIN SHINER (NO!:fQEi§ §E~!QE!:g!Y§) * * *

• Food Habits *************

Reproduction. * * * * * * * * * * *

• Age and Growth. * * * * * * * * * *

• BLUNTNOSE MINNOW (gi~E.halg§ ~Q!:~~Y§) * * *

• Reproduction. * * * * * * * * *

• GIZZARD SHAD (QQ!Q§Q~ £~E~9!~n~m) * *

• Reproduction. * * * * * * * ***

WALLEYE (.§!:izo2tegion vi!:;:g!!m> * *

• Food Habits * * * * * * * * * * * *

• Reproduction. * * *.

Age and Growth. * * * * * * * * * * * * *

• LARGEMOUTH BASS (Mi£;:QQ~~~~2 2~!mQiges)

Food Habits * * * * * * ****.**

Reproduction. * * * * * * * * * * *

• Age and Growth. * * * * * * * * * * * * *

• SMALLMOUTH BASS (Mi£~QE~g~~2 dO!Qmieui)

Food Habits * *

• Reproduction. * * * * * **********

Age and Growth. * * *

• MOVEMENT OF FISHES. *

• Movement of Fishes in Conowingo Pond.

Movement of Fishes in the Plume NATURAL MORTALITIES OF FISHES IN CONOWINGO PONO. * * *

• RECREATIONAL FISHERY *****........

ix 7.2-2 7.2-19 7.2-19 7.2-20 7.3-1 7.3-2 7.3-2 7.3-2 7.3-3 7.3-5 7.3-5 7.3-25 7.3-25 7.3-25 7.3-25 7.3-26 7.3-33 7.3-33 7.3-33 7.3-33 7.3-37 7.3-37 7.3-~

7.3-:.

7. 3-4 1 7.3-41 7.3-41

7. 3-41 7.3-43 7.3-43 7.3-43 7.3-43

7. 3-4 5 7.3-45

7. 3-4 5 7.3-45 7.3-47 7.3-47

7. 3-4 7 7.3-47 7.3-49 7.3-49

7. 3-4 9 7.3-50 7.3-53

l I i I

I t I ' i *

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~

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7.4.0 TEMPERATURE EXPERIMENTS WITH FISHES TEMPERATURE PREFERENCE. * * *

• Spotfin shiner ********

Falling Field Temperatures.

Rising Field Temperatures

• Channel catfish * * *. * * * *.

7. 4. 1 7.4.1.1 7.4.1.1.1 7.4.1.1.2 7.4.1.2 7.4.1.2.1 7.4.1.2.2 7.4.1.3 7.4.1.3.1 7.4.1.3.2 7.4.1.4 7.4.1.4.1 7.4.1.4.2 7.4.1.5 7.4.1.5.1 7.4.1.5.2 7.4.1.6 7.4.2 7.4.2.1 7.4.2.1.1 7.4.2*.1.2 7.4.2.2 7.4.2.2.1 7.4.2.2.2 7.4.2.3 7.4.2.3.1 7.4.2.4 7.4.2.4.1 7.4.2.4.2 7.4.2.5 7.4.2.5.1 7.4.2.5.2 7.4.2.6 7.4.3 7.4.3.1 7.4.3.2 7.4.3.3 7.4.3.4 7.4.3.5 7.4.4 8.0

8. 1 8.2 8.3 8.4 8.5 Falling Field Temperatures.

Rising Field Temperatures * *. * * * *

• Pumpkinseed. * * * * *. *.

Falling Field Temperatures.*.*****

Rising Field Temperatures

• Bluegill Falling Field Temperatures.

Rising Field Temperatures.

White crappie ********

Falling Field Temperatures ***

Rising Field Temperatures Other Species * * * * * * *.

TEL\\IPERATURE AVOIDANCE * * * *

• Spotfin shiner *****.****

Falling Field Temperatures.

Rising Field Temperatures

• Channel catfish * * * * * * * *.

• Falling Field Temperatures. *

• Rising Field Temperatures

• Pumpkinseed * * * * *. *.

• Rising and Falling Field Temperatures *

• Bluegill. * * * * * * * * *

• Falling Field Temperatures.

Rising Field Temperatures

• White crappie * * * * * * *

• Falling Field Temperatures.

Rising Field Temperatures Other Species *.

TEMPERATURE SHOCK * * * *. * * * * * * * *

• Spotf in shiner Channel catfish

• Pumpkinseed Bluegill White crappie *

• DISCUSSION ALTERNATIVE #1 -

FIVE 11HELPER 11 COOLING TOWERS Applicable Effluent Limitation *.***

System Description.

Schedule and costs.

Resultant Isotherms ***

Biological Impact * * *

• x 7.4-1 7.4-1 7.4-2 7.4-2 7.4-2 7.4-2 7.4-2 7.4-2 7.4-2 7.4-2 7.4-3 7.4-3 7.4-3 7.4-3 7.4-3

7. 4-3 7.4-3 7.4-4 7.4-7 7.4-7

7. 4-7 7.4-7 7.4-7

7. 4-7 7.4-7 7.4-8 7.4-8 7.4-8 7.4-8 7.4-8 7.4-8 7.4-8 7.4-8

7. 4-8 7.4-11 7.4-11 7.4-11 7.4-12 7.4-12 7.4-12 7.4-13 8-1 8-1 8-1 8-1 8-2 8-3

9.0 ALTERNATIVE #2 -

FIVE "HELPER" COOLING TOWERS WITH STUDIES * * * * * * *.

9.1 Applicable Effluent Limitations.

9.2 System Description...

9.3 Schedule and Costs *.**

9.4 Resultant Isotherms *.***

9.5 Biological Impact *.*

10.0

10. 1 10.2 10.3 10.4 10.5

11. 0 ALTERNATIVE #3 -

FIVE COOLING TOWERS, VARIABLE BLOWDOWN * * * * *

• Applicable Effluent Limitations

• System Description..

Schedule and Costs *.*

Resul~ant Isotherms

• Biological Impac~

LITERATURE CITED xi 9-1 9-1 9-1 9-1 9-2 9-2 10-1 10-1 10-1 10-1 10-2 10-2 11-1

r*

I I.

I I,.

I l SF.CTI ON 2. 0 Table

2. 2-1 2.2-2

2. 2-3

2. 3-1 LIST OF TABLES PLANT OPERATING DATA Seasonal Variation of Discharge Delta T **

Seasonal Variation of Rate of Evaporative Loss *****

Circulating Water Transit Times.

Chemical Discharges in cooling Water **.*

xii Page 2-5 2-6 2-7 2-17

SECTION 2. 0 Figure 2.2-1

2. 2-2 2.2-3 2.2-4 2.2-5 2.2-6 LIST OF FIGURES PLANT OPERATING DATA Closeup of Peach Bottom complex.

• Condenser Delta T vs. Unit Load Submerged Discharge Facility ***

Path of Cooling Water Through Plant.

• July Temperature - Time Profile ****

November Temperature - Time Profile **

xiii Page 2-9 2-10 2-11 2-12 2-13 2-14

SF.CT ION 3. 0 Table

3. 1-1 SECTION 4. 0

4. 2-1 4.5-1

4. 5-2

4. 5-3 LIST OF TABLES PLANT OPERATIONAL EXPERIENCE TO DATE PBAPS Average and Monthly Generation by Month, February 1974 through May 1975

• SUSQUEHANNA RIVER HYDROLOGY Summary of Susquehanna River Water Temperatures (1936-1966) 7-Day Low Flows and Corresponding Temperatures Median 7-Day Low Flows and Temperatures **

Joint Probability Distribution Between Temperature and Flow * * * * *.

• xiv Page 3-3 4-3 4-5 4-6 4-7

f f

I I

J i* :,

SECTION 4.0 Figure 4.1-1

4. 1-2 4.1-3 to

4. 1-5

4. 1-6

4. 1-7 to 4.1-10 4.2-1 4.4-1 to 4.4-7 LIST OF FIGURES SUSQUEHANNA RIVER HYDROLOGY Susquehanna River Basin *******

Lower Susquehanna River Hydro Plants

• Inf low and Discharge at Conowingo Pond Flow Duration curves * * * * * *

• 7-Day Low Flow Recurrence Interval (monthly) * *. * * * * * * *

• Range of Water Temperatures **

Bottom Contours of Conowingo Pond.

xv Page 4-9 4-10 4-11 4-14 4-15 4-19 4-20

ff I

1:

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SECTION 5.0 Table 5.0-1 SECTION 6. 0

6. 4-1 LIST OF TABLES METEOROLOGICAL DATA Monthly Meteorological Data. *......

THERMAL PLUME CHARACTERISTICS Thermal Generating Stations between Harrisburg and Peach Bottom. * * * *

.xvi Page 5-1 6-3

),

r.,,

SECTION 6. 0 Figure 6.2-1 to 6.2-8

6. 3-1 6.3-2

6. 3-3 6.3-4 6.3-5 6.3-6 6.3-2 LIST OF FIGURES THERMAL PLUME CHARACTERISTICS Selected Observed Isotherms and Associated Data surface Discharge Isotherms......

surface Plume Veloci~y ***

5 Ft. Depth Discharge Isotherm *

• 5 Ft Depth Plume Velocity ***

10 Ft. Depth Discharge Isotherm **

10 Ft. Depth Plume Velocity.*.

Centerline Plume Velocity vs. Distance from Discharge and *. * * * *. * *

• xvii Page 6-4 6-20 6-21 6-22 6-23 6-24 6-25 6-26.--...

LIST OF TABLES SECTION 7.1.0 LIMNOLOGY OF CONOWINGO POND Table

7. 1. 2-1 7.1.2-2 to

7. 1. 2-3

7. 1. 2-4

7. 1. 2-5

7. 1. 3-1

7. 1. 3-2 7.1.3-3 7.1.3-4 Comparison of the monthly mean values of Water quality parameters measured during the preoperational (1967-1973) and post-operational (1974} periods in conowingo Pond *. * * *... *..

Maximum and minimum weekly water tem-peratures measured at Holtwood Dam, 1966-1974 ***************

Comparison of the seasonal ver~ical distribution of dissolved oxygen during the preoperational (1967-1973} and postoperational (1974) periods in stations in and outside the thermal plume in Conowingo Pond. * * * * **

Monthly values of biochemical oxygen demand from samples collected at conowingo Darn, 1960-1967.

Data supplied by storet Syst~m of the Environ-mental Protection Agency *. * * *

• List of Genera of algae collected in Conowingo Pond, 1967-1969 ******

Monthly variations in the percentage composition of the major groups of algae in Conowingo Pond, 1967-1969

• comparison of the monthly mean plant pigments concentrations during the pre-operationaL (1971-1973} and post-operational (1974} periods in conowingo Pond............ *......

Values of Chlorophyll ~ (mg/m3)

• nitrates, phosphat~s (ppm), water temperature, daily river flow (x 1,000 cfs} and zooplankton densities during the pre-operational (1971-1973) and post-operational (1974} periods in conowingo Pond...... *. * * * * *.. * * *.

xviii Page

7. 1-5

7. 1-8

7. 1-9

7. 1-10 7.1-17 7.1-18 J.1-19

7. 1-20

f.

~*

Table

7. 1. 3-5 7.1.3-6

7. 1. 4-1 7.1.4-2

7. 1. 4-3

7. 1. 4-4 7.1.4-5

7. 1. 4-6 7.1.4-7

7. 1. 5-1 Regression statistics for the concen-tration of total chlorophyll ~ (mg/m3) and physiochemical parameters in Conowingo Pond, 197 3 * * * * * *

• List of macrophytic aquatic plants found in Conowingo Pond. * *. * * * *. * * *.

zooplankton taxa collected from Conowingo Pond * * * * * *. * *. *.

Annual species composition of zooplankton in conowingo Pond, 1967-1974 *.**.

Comparison of the monthly density of common taxa of zooplankton (no./liter) during the preoperationa~ (1967-1973) and postoperational (1974) periods in Conowingo Pond * * * * * * * * *..

Comparison of the monthly density of total zooplankton (no./liter) during the preoperational (1967-1973) and post-operational (1974) period in Conowingo Pond...

Total chlorophyll ~ (mg/m3), nitrates, phosphates (ppm), water temperature, daily river flow and zooplankton density during the preoperational (1971-1973),

and postoperational (1974) periods in Conowingo Pond * * * * * * *. * * *

• Regression equations for predicting zooplankton densities at Stations 602-611 in conowingo Pond. * *

• Regression equations between the total zooplankton density at station 601-611 and average water temperature, river flow and degree days in conowingo Pond List of benthos taxa collected in Conowingo Pond, 1967-1974 ***

xix Page 7.1-21

7. 1-22

7. 1-33

7. 1-34 7.1-35 7.1-3 7.1-36

7. 1-37 7.1-38 7.1-47

r l.

1 j

!~.

I Table 7.1.5-2

7. 1. 5-3 7.1.5-4 to 7.1.5-5 7.1.5-6

7. 1. 5-7 7.1.5-8

7. 1. 5-9 Mean number (per 81 in.2) and per-centage composition of benthic organisms collected during the preoperational (1967-1973) and postoperational (1974) periods in Conowingo Pond. * * * * *

• Percentage composition of bottom sedi-ments in terms of particle size at limnological stations in conowingo Pond, 27 July 1972 ***************

Species diversity and equitability indices by month and by station for benthic organisms collected at limnological stations during the preoperational (1967-1973) and postoperational (1974) periods in conowingo Pond. * * * * * * * * * * *

• Mean number (per 81 in.2) of the selected representative species of benthic organisms collected at Stations 601-611 during the preoperational (1967-1973) and postoperational (1974) periods in Conowingo Pond * * *. * * * * * * * * *.

Spearman rank correlation (rs) test between years indensities of the selected representative taxa of benthos at Stations 601-611 in conowingo Pond ***.

Percentage similarity of Stations 601-611 between years in conowingo Pond, 1967-197q **************

Comparison of the monthly mean biomass (mg/dry weight) per 81 in.2 at stations during the preoperational (1967-1973) and postoperational (1974) periods in Conowinqo Pond * * * *. * * * * * * * *

• xx Page

7. 1-49

7. 1-52

7. 1-53

7. 1-55 7.1-56

7. 1-57 7.1-58

t *..

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LIST OF FIGURES SECTION 7.1.0 LIMNOLOGY OF CONOWINGO POND Figure

7. 1-1

7. 1. 3-1 to 7.1.3-4 7.1.3-5 7.1.3-6 7.1.4-1 7.1.4-2 to 7.1.4-4 7.1.5-1 7.1.5-2 to

7. 1. 5-5 Distribution of limnological stations in conowingo Pond. *. * * * * * * *

• Average total chlorophyll ~ (mg/m3) concentrations at Stations 601-605 in Conowingo Pond, 1971-197 4. * * * *

• Plot of total chlorophyll ~ (mg/m3),

nitrates and phosphates (ppm) in Conowingo Pond, 1971-197Ll ******

Map of Conowingo Pond showing distribution of aquatic macrophytes.

Plot of total zooplankton density (no./liter), average daily river flow and water temperature in Conowingo Pond, 1971-1974 Confidence limits of the observed vs.

estimated values of total zooplankton density at stations 602-611.****

Plot of number of taxa (species richness),

species diversity and equitability indices for benthic organisms in conowingo Pond, 1967-1974 ****************

Relative densities of the selected representative taxa of benthos at stations in Conowingo Pond, 1967-1974 *******

xxi Page 7.1-11

7. 1-23

7. 1-27

7. 1-28

7. 1-39 7.1-40

7. 1-59

7. 1-60

r

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I SECTION 7.2.0 Table

7. 2. 2-1 7.2.2-2 7.2.2-3 to 7.2.2-8 7.2.3-1 7.2.3-2 7.2.3-3 to 7.2.3-4 7.2.3-5 LIST OF TABLES ABUNDANCE AND DISTRIBUTION OF FISHES List of scientific and common names of fishes collected in Conowingo Pond and tributary streams catch per effort for fishes collected by various gears in Conowingo Pond *

• comparison of catch per effort for fishes collected by various gears during the preoperational (1966-1973) and post-operational (1974) periods in Conowingo Pond * * * * *. * * * *.

comparison of the monthly mean bottom water temperature at Trap Net Stations in and outside the thermal plume of Peach Bottom Station Units No. 2 and 3 in conowingo Pond, July 1974-March 1975.*************

comparison of catch per effort (number per 24-hour) for fishes collected by trap net at the monitoring stations, discharge canal and plume stations in conowingo Pond, July 1974-March 1975

• comparison of the catch per effort (number per 24-hour) of selected representative fishes collected in the discharge canal and at Station 110 during the preoperational (1967-1973) and postoperational (1974), periods in conowingo Pond. * * * * * * *

• Bottom water temperature, delta T, percentage power of Units No. 2 and 3, daily river flow at trawl stations in and outside the thermal plume Peach Bottom Station Units 2 and 3 in Conowingo Pond * * * * * * * * * * * * * * * * * *

• xx ii Page 7.2-5 7.2-6 7.2-7

7. 2-23 7.2-24 7.2-25

7. 2-27

I Table 7.2.3-6 Catch per effort (number per 10-min. haul) for fishes collected by trawl at stations in and outside the thermal plume of Pea*ch Bottom Station Units No. 2 and 3 in Conowingo Pond. * * *

• xxiii Page

~*~

7. 2-29

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LIST OF FIGURES

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SECTION 7.2.0 ABUNDANCE AND DISTRIBUTION OF FISHES Figure 7.2.1-1 to 7.2.1-5 7.2.3-1

1. 2. 3-2 Map of Conowingo Pond showing the distribution of Trap Net, Trawl Trans-ect, Trawl Zone, Seine and Meter Net Stations in conowingo Pond * *

• Map showing the location of Trap Net Stations in the thermal plume of Peach Bottom station Units No. 2 and 3 Location of trawl stations in and outside the thermal plume of Peach Bottom Station Units No. 2 and 3 in conowingo Pond * * * * * * * * *. * * * * * *

• xxiv Page 7.2-13

7. 2-31 7.2-32

LIST OF TABLES SECTION 7.3.0 BIOLOGY OF FISHES Table 7.3.1-1 catch of larval fishes (S25mm) at various locations during the pre-operational (1967-1973) and post-operational (1974) periods in Conowingo Pond * * * * * * * * * * * *

• 7.3.1-2 catch of larval fishes (S25mm) at stations on the west shore, mid-pond and east shore during the preoperational (1967-1973) and postoperational (1974) periods in Conowingo Pond 7.3.1-3 Comparison of the fecundity data on white crappie from various studies * * * * * *

• 7.3.1-4 Growth indices for white crappie, gQIDQ~l§ fil!UYla~i2 collected by trap net during the preoperational (1966-1973) and postoperational (1974) periods in 7.3.1-5 7.3.1-6 7.3.1-7 7.3.1-8 7.3.1-9 Conowingo Pond * * * * * * * * * * *

• Time of annulus formation of I, II, and III year old crappie, ~Q~!§ ~nn~la~!§,

collected from conowingo Pond 1967-1970 **

A comparison of calculated growth rate for white crappie, Pom2~!2 2nn~l~ri§,

from various parts of the country. *

• Estimates of survival rates of various year classes of white crappie, FQ!!!Q~is annylari2 in Conowingo Pond Catch per effort (number per 24-hr) for various age groups of tne 1966-1974 year classes of the white crappie, ~QIDQ~!§

~nnula~i§, collected by trap net in conowingo Pond * * * * * * * * * * * * *

• Estimates of survival rates between two successive age groups of individual year classes of white crappie, fQmo~!§ ann~!~ri§ in Conowingo Pond xxv Page 7.3-7 7.3-8

7. 3-9

7. 3-10....

7.3-11 7.3-13 7.3-14 7.3-15

7. 3-15

I v

:> *Ta.hie

. 7. 3. 2-1 7.3.3-1 7.3.4-1 7.3.7-1 7.3.8-1 7.3.9-1 7.3.11-1

7. 3. 12-,

Comparison of growth rates for the channel catfish, !ctal~~~§ E!!llfta~g§ from various parts of the country * * * *

• comparison of growth rates for the blue-gill, Le:QQmi2 m~~Qchi!Y2 from various parts of the country * * * *

• Food of the spotfin shiner, ~Qt!QEi~

22i1QE~g!~§ in Conowingo Pond, 1967-1968

• comparison of growth rates of the walleye, 2~i~Q§~ediQn Yitr~m from various parts of the country * *

• comparison of growth rates of largemouth bass, Mi£~Q.Qterg~ ~almQig~, from various parts of the country * * * * * *

• comparison of growth rate for the small-mouth bass, Mi£ropte~~2 gQ!Qmi~yi, from various parts of the country * * * * * *

• Species composition of dead fishes ob-served during the preoperational (1966-1973) and postoperational (1974) periods in Conowingo Pond Species composition of fishes caught by anglers during the winter (Januray-March) creel sensus of Conowingo Pond, 1973 and 197 4 *. *. *.. * *.

• xxvi Page

7. 3-27

7. 3-35 7.3-39 7.3-44

7. 3-46

7. 3-48 7.3-51

7. 3-55

f SECTION 7. 3. 0 Figure 7.3. 1-1 7.3. 1-2 7.3.1-3 7.3.1-4 7.3. 1-5 7.3.1-6 to 7.3.1-9 7.3. 1-10 7.3.2-1 to 7.3.2-2 LIST OF FIGURES BIOLOGY OF FISHES seasonal variations in mean gonosomatic index of the white crappie, ~QffiQ~i§

~nnYl2~is, and water temperature during the preoperational (1971-1973) and postoperational (1974) periods in conowingo Pond * * * * * * * * *

• Range of surface water temperatures at which larvae (S25mm) of the selected representative fishes were collected in Conowingo Pond, 1969-1973 *****

Distribution of larvae of* the white crappie, fQm~!2 2Dill!!2!!§, at plankton net stations in conowingo Pond, 1969-1973 Abundance of various age groups of the white crappie, ~QfilQ~i§ fillDYla~i~,

collected by trap net during the pre-operational (1966-1973) and post-operational (1974) periods in Conowingo Pond

• Growth of the 1966-1974 year classes of the white crappies, gQIDQ~i2 ~nnul2fi£ in conowingo Pond. * * * *. * * * * *.

• Monthly growth of the O, I, II, and III year old white crappie, fQfilQXi§ ~nngla~i§,

collected during the preoperational (1966-1973) and postoperational (1974) periods in Conowingo Pond. * * * * *

• Year class strength of the white crappie fQfilQ~i2 ~nnYla£i§ in Conowingo Pond, 1966-1974 **************** 41 Calculated growth curve and growth history of the 1958-1968 year classes of the channel catfish, !£~2lY~Y§ EYn2ta~~§ in Conowingo Pond. *. * * * * * *

• xxvii Page 7.3-17 7.3-18

7. 3-19

7. 3-20 7.3-21 7.3-22

7. 3-24

7. 3-29

r I I I !*

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Figure 7.3.2-1 7.3.2-4 7.3.2-5 1.3.3-1 7.3.4-1 7.3.6-1 Plot of the monthly growth rates of young and yearling channel catfish I£~~!~ru§ E~n£~2~~§ and mean monthly water temperatures in Conowingo Pond.

Distribution of larvae (S25mm) of the channel catfish, !£~2!~rY2 2!:!D£~~~~2 at Plankton net stations in Conowingo Page 7.3-30 Pond 7.3-31 Year class strength of the channel catfish I£~s!~~~§ 2Yn£~~~Y§ in conowingo Pond, 1966-1974 7.3-32 Distribution of larvae (~25mm} of the blue-gill, b~22.m!§ mac~£biI~2 at plankton net stations in Conowingo Pond * * * * * *.

• 7.3-36 Distribution of larvae

(~25mm) of the spot-f in shiner, NQt~Ei.2 2P!lopte!Y2 at plankton net stations in Conowingo Pond * * *

• 7.3-40 Distribution of larvae

(~25mm) of the gizzard shad, QQ~Q§Qill~ £~~Qi~n!:!m at plankton net stations in Conowingo Pond.

• 7.3-42 xxviii

l I..

i '

SECTION 7.4.0 Table 7.4.1-1 7.4.1-2 7.4.2-1 7.4.2-2

7. 4. 4-1 7.4.4-2 LIST OF TABLES TEMPERATURE EXPERIMENTS WITH FISHES Regression equations of the preferred temperatures (Y), acclimation tempera-ture (X1) and mean total length (X2) for the spotfin shiner, channel cat-fish, pumpkinseed, bluegill, and white crappie for falling and rising field temperatures * * * * * * * * * * * *

• summary of temper~ture preference data on othe~ selected representative species Regression equations of the avoidance temperature (Y), acclimation temperature (X1), and mean total length (X2) for the spotfin shiner, channel catfish, blue-gill and white crappie for falling and rising field temperatures Summary of temperature avoidance data on other selected representative species Preference, avoidance and uppper temperature (F) tolerance limits of the selected representative fish acclimated to high summer temperatures common to conowingo Pond * * * * * * * * * * *

• Preference and avoidance temperatures of selected representative fishes acclimated to 33, 40, and 55 F ****

xxix Page 7.4-5

7. 4-6 7.4-9 7.4-1 7.4-15 7.4-16

SECTION 7.4.0 Figure

7. 4. 1-1 to 7.4.1-5 7.4.4-1 to 7.4.4-5 LIST OF FIGURES TEMPERATURE EXPERIMENTS WITH FISHES Relationship between rapid temperature increase (shock) and preference and avoidance temperatures (953 confidence intervals of the population mean) during falling and rising field temperatures for the spotfin shiner, channel catfish, pumpkinseed, blue-gill and white crappie * * * *.. *...

• Plot of rapid temperature decrease test (shock) in relation to water quality criteria (maximum increase in delta T = 5 F) and delta T = 15 F for the spotfin shiner, channel catfish, pumpkin-seed, bluegill, and white crappie *****

xxx Page 7.4-17

7. 4-22

l, :*

SECTION 8.0 Table 8.2-1 8.2-2 SECTION 10.0 10.2-1 10.2-2 LIST OF TABLES ALTERNATIVE # 1 seasonal variation of Discharge Delta T.

Seasonal Variation of Rate of Evaporative Loss..................

ALTERNATIVE # 3 seasonal Variation of Blowdown....

Seasonal Variation Of Ev.aporati ve Loss.

xxxi Page

..... 8-3

..... 8-4 10-3

..... 10-4

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SECTION 8.0 Figure

8. 2-1 8.4-1 to 8.~-6c LIST OF FIGURES ALTERNATE # 1 Closeup of Peach Bottom Complex * *.

Peach Bottom Model Study, Predicted Conowingo Pond Temperature Rise Above Page 8-5 Ambient Water Temperature. *. * * * * *. * * *

• 8-6 SECTION 10. 0 ALTERNATIVE # 3 10.2-1

10. 2-2 Proposed Mixing Zone for Alternative# 3 * * * *

• 10-5 Closeup of Peach Bottom complex *****..*** 10-6 xxxii

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1. 0 INTRODUCTION This document was prepared in support of Philadelphia Electric Company's (hereafter "Company")

application to the Environmental Protection Agency for the imposition of effluent limitations for its Peach Bottom Atomic Power Station, Units 2 and 3 (designated hereafter as PBAPS) which are less stringent than would be produced by a closed cycle cooling system, but yet sufficiently st.ringent to assure the protection and propagation of a

balanced indigenous community of shellfish, fish and wildlife in and on Conowingo Pond.

By letter dated December 5, 1974, the Company had requested a

determination pursuant to Section 316(a) of the Federal Water Pollution control Act and suggested to EPA that certain species be designated representative species to be utilized in a demonstration pursuant to that section.

On December 17,

1974, the Company met with representatives of EPA, the Commonwealth of Pennsylvania and the State of Maryland at Ichthyological Associates*

Muddy Run Laboratory to discuss the planned demonstrations and to view the facility and conowingo Pond.

on May 27,

1975, the Company submitted to EPA a

preliminary description of the desired alternative effluent limita~ions wi~

several contingent alternatives including a

schedule f~

construction of equipment associated with the contingent alternatives.

The following is a

statement of the effluent limitations requested together with the proposed alternatives thereto and associated Schedule for completion.

~ffl~~n~ ~imi~~~ion Reg~~steg The **company* s preferred alternative *effluent limitation is one which corresponds to the facility as presently designed, constructed, and operated.

The present design of the facility with regard to the thermal component of the discharge is sufficient to assure the protection and propagation of a balanced indigenous population (community) of shellfishes, fishes, and wildlife in and on the body of water into which the discharge is made, i.e., Conowingo Pond ("Pond").

The present design consists of an open cycle cooling system utilizing three mechanical draft "helper" cooling towers cooling 58 percent of the flow which is mixed with the remaining 42 percent of the flow being discharged via a submerged jet discharge to the Pond.

The discharge to the Pond would average 12x109 Btu/hr.

1-1

r r--

Should the ultimate determination under Section 316(a) as to I

this alternative be that it is not stringent enough to satisfy the section 316(a) standard in lieu of applicable effluent limiations, water quality standards or other requirements, if

any, the company would propose the next following and correspondingly more stringent effluent limitations:

After obtaining all necessary regulatory approvals, the Company would commence the installation of two additional helper cooling towers which would provide sufficient capacity to accommodate the total circulating water flow and thus cool all of the circulating water before discharging it to the Pond.

The total five tower system would about double the cooling capacity of the present three tower

system, in that essentially 100 percent of the flow through the condensers would pass through the cooling towers instead of about 58 percent with the present system.

The discharge to the Pond would average 8.Sx109 Btu/hr.

A further description of this system and its operation is contained herein (see section 8).

A schedule for construction of these facilities is discussed, infr~.

During the construction of the facilities, the Company would propose that the Section 316(a) standard would be satisfied by a

schedule of compliance corresponding to the construction schedule and certain agreed upon interim operating conditions.

~Q~~1ng~n~ 81te!nati~ ~

In the event the determination should be made that the evidence submitted in support of Contingent Alternative 1 is not sufficient to clearly demonstrate its suitability as a means of satisfying the requirements of Section 316(a), the company would propose the following measures.

The company would construct two additional helper cooling towers as described in Contingent Alternative 1 and undertake a comprehensive biological monitoring program to verify the adequacy of the system.

If, after one year of full power operation and monitoring with the five tower system, it were determined that Section 316(a) was no~ being satisfied, the Company would construct a

sheet-pile return channel (or other suitable return) which in conjunction with the five tower system and other plant modifications, could be operated over a range of discharge (blowdown) modes from open cycle to closed cycle.

The system would have the capability of regulating blowdown rates such that the discharge may be in amounts

which, although perhaps greater than 11blowdown" as defined in 40 CFR section 423. 11 (e),

would nonetheless be controlled so as to assure the protection and propagation of a 1-2

.*"-t :t~

balanced indigenous population (community) of shellf is~es~

fishes, and wildlife in and on the Pond.

The measures requirE to complete this system and its mode of operation are discusse~

in sections 9 and 10.

During installation of the return channel and performance of other necessary modifications or for the longer term, the system would be operated such that thermal discharges are controlled in accordance with certain agreed upon operating conditions.

Should it be determined, on the basis of the information submitted pursuant to 40 CFR Section 122. 5 (b) ( 1),

and other appropriate record evidence that the proposed alternative effluent limitation or Contingent Alternatives 1 or 2 would not produce effluent limitations which were sufficiently stringent to assure the protection and propagation of a balanced indig~nous community in the Pond, the Company would propose to concurrently install two additional helper cooling towers and install a return

channel, which in conjunction with other plant modifications would provide a system which could be operated over a

range of discharge modes from open cycle to closed cycle.

(See Section 10.) This combination amounts to contingent Alterna~ive 3.

The determination of the operating mode would proceed as in Contingent Alternative 2.

A schedule for the installation of this equipment is provided, infr~.

It may be noted that since the variable blowdown syst~

described herein could be operated as a closed cycle one with minor

blowdown, in the unlikely event it were ultimately determined that the foregoing alternatives and corresponding effluent limitations did not satisfy section 316{a),

the facility, assuming the schedules set forth herein, could be operated in substantial compliance with 40 CFR section 423.13(1) by July 1, 1981, the date for meeting national thermal effluent limitations* for - plants of *the class of Peach Bottom, i.e.,

existing sources.

Qfill!~l Qf ~l~§~n~tiy~

Should it ultimately be determined that the imposition of alternative, less stringent effluent limitations are not warranted, the Company would nevertheless request that a Schedule of Compliance be established under section 316(a) or otherwise to allow interim operation under such conditions as may be justified, pending completion of the closed cycle system, as mandated by 40 CFR section 423.13(1), by July 1,

1981, or such later date as may be in accordance with law, but in any event no 1-3

r i

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r. i, earlier than the schedule proposed in conjunction with contingent Alternative 3.

Because of the nature of certain of the contingent alternative effluent limitations outlined above and because of the time necessary for installation of equipment necessary to meet those contingent effluent limitations, and the test and monitoring program which may have to be conducted upon the completion of the installation of such equipment, should the Regional Administrator decide that the information submitted herewith is not sufficient to make a final determination, it may be necessary that the Administrator's final determination of alternative effluent limitations be deferred pursuant to 40 CFR Section 122.S(c).

The information which would be submitted as part of such a

def erred plan of study and demonstration would be the results of (and an analysis thereof) a continuation of the type of monitoring done to date and discussed h~rein.

In addition, information concerning the isotherms observed during the additional study period and other physical data taken would be submitted.

The type of information would be responsive to any requirement which might reasonably be imposed by the Regional Administrator as part of his decision.

Should such a plan of study and demons~ration be required,

~he Company would request that it be allowed to gather and analyze one year's data subsequent to completion of the required equipment which would be installed in accordance with the schedule below:

SCHEDULE FOR COMPLETION

~!f ly~n~-l:i!ID!~s~ion_B~gBg~teg No additional construction or equipment is required.

con~!ng~!}! Altefn~tiyg 1 After receipt of last regulatory approval, it would take approximately 30 months to construct two additional cooling towers, assuming completion of engineering and availability of long lead time items.

~Qn~ing~n~ Al~gfnatiY§ ~ -

(if required to install return channel after analysis of operation with five towers).

After receipt of 1-4

last regulatory approval necessary for commencement o~

construction, the construction and modifications necessary wou:

take approximately 23 months to complete.

~2nt!ng~ Alternative J After receipt of last regulatory approval it -WOuld -take approximately 30 months to complete necessary construction and modifications, assuming completion of engineering and availability of long lead time items.

This document is generally organized in accordance with EP~

Region III guidance contained in "316(a) Technical Guidance --

Thermal Discharges" dated September 30, 1974.

section 1 contains a narrative description of the impact expected to occur to the indigenous biological communities due to the thermal effluent from PBAPS and the expected effects of operation of PBAPS on the Pond.

section 2 presents a description of the facility and its operation.

Section 3 describes plant operating experience to date and the biological effects of plant shutdowns.

section 4 discusses Susquehanna River hydrology and the conowingo Pond.

section 5 describes the meteorology that was utilized in cooling tower and pond thermal performance studies.

section 6 describes the thermal plume characteristics of the plant as designed.

section 1

provides a

detailed description of the aquatic community and analysis of the effect of operations to date.

Sections 8, 9, and 10 describe in further detail the contingent alternatives.

Chapter 11 contains citation to the literature.

The primary and three contingent alternative cooling systems ar.-....

presented and their impact upon the biota are aiscussed.

The environmental and biological studies of conowingo Pond for both the preoperational and the postoperational periods, have been reported in detail in gobQiil§

~ng M2~hY~

11274~L Q

~nd 1915sL £L £l*

Based on these and other extensive ecological studies, R2n~ 1197Jt predicted an overall enhancement in the recreational values of the Pond.

It is the applicant's belief that the "representative, important species" will not be harmed as a

result of the designed operation of PBAPS and that "the protection and propogation of a balanced, indigenous community of shellfish, fish and wildlife" will be assured.

The designated species and/or biological communities evaluated are, for fishes:

gizzard shad, QQ!:OSQffis QgE~dia!l.!!m, channel catfish,

!£t~1gfus pungtat~§, bluegill sunfish, bgEQ!!!i.2. fil~!:Q£hi!Y§, white crappie, fQ!!!QXi§. annulaf!..§, walleye pike,

§i!~Q2~~g!Qn vi:t£~~m, spotf in

shiner, NQtrQQ!.§.

§.Pi!Q.12~.§.,

bluntnose

minnow, Pim~Qhal~

n2~~tu§, largemouth bass, Mi£fQp~g~y.§. §almoig~~, smallmouth bass,

~i£rQB~~!Y.2. gQ!Qmi~y!; for benthic invertebrates:

f!:2£!~9iY2 sp.

or

£hi!QilQffiY§ sp.,

£haobofy§ p!:!.!1£tiQgnn!§,

~im~Qg~ilus 1-5

r.

J r

hoffmeisteri,

~~~~~!~ !imbat~; and for biological communities:

evaiuation-of the thermal discharge effect on the phyto-and zooplankton communities.

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conowingo Pond is a main stream impoundment on the lower Susquehanna River in southeastern Pennsylvania and northern Maryland.

It is approximately 14 miles long and one mile wide.

Pond depths vary from 15 ft to approximately 90 ft. at conowingo Dam.

Normal Pond elevation is 108.5 ft CD (Conowingo Datum; 0.72 ft. above MSL) with a maximum operational drawdown elevation of 98.5 ft co.

Biological studies were initiated in June 1966 at the Muddy Run Pumped Storage Power Station as a

result of Federal Power Commission License No. 2355, Article 40, to determine the design of fish protective facilities as may be needed at the project.

Initially the study included only the northern half of the Pond in the vicinity of the Muddy Run Station.

In the spring of 1967 the study was expanded to include the entire Pond because of the planned construction of Units No. 2 and 3

of the Peach Bottom Atomic Power station.

From 1966 to the

present, studies were made on the t'*

ecology of the Pond and connecting waters by Ichthyological Associates.

Approximately 125 biologists, chemists and other specialists participated and have contributed more than 175 man-years of investigations.

Presently, 29 full-time scientists and support personnel are working on the ~tudies.

To date abou~ 20 man-years (combined personnel of Ichthyological Associates and Philadelphia Electric Company) have been expended to establish a computer data base containing the ecological information.

The objective of the study of the Pond was to determine baseline ecological conditions, which included determination of water quality and the species composition, distribution and fluctuations in abundance of the biota prior to the operation of PBAPS.

Experimental studies were conducted to determine the swimming speed of fishes and the thermal preference, avoidance and effects of sudden decrease and increase in temperature on fishes.

The limnological and fishery studies in the based on a large number of collections (over 16,000).

conditions are derived from the data from monitoring which have existed from the initial sampling date to the Pond are Baseline stations present.

Beginning in September 1973 PBAPS operated at varying power loads reaching full power of Unit No. 2 in June 1974.

1-6

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Since June 1974r PBAPS began operating on a regular schedule~

All data taken from the various environmental monitoring progra:

during 1974 is considered to be postoperational.

Data collecteu from the peroperational period (1966 to 1973) are compared with those from the postoperational period.

No deleterious effects were observed on the abundance and distribution of the biota in the Pond during the postoperational period.

All information contained in this document has been supplied in summary form so the review can be conducted without supplemental reports.

Each section contains references to the particular documents where detailed data can be obtained.

In a similar mannerr only the results of analysis are contained herein.

References are given for the detailed documents.

Ichthyological Associates has provided in Section 7.0 sufficient analysis of raw data to enable the fundamental relationships to be understood.

Statistical analysis has been provided by Philadelphia Electric company personnel and is presented as reference documents.

All analysis is directed toward detecting changes in the ecology of conowingo Pond in the postoperational period.

The reports prepared by Philadelphia Electric company covering the statistical analyses of the data collected by our consultants are listed below by subject with brief comments as to content:

-~

1 Analysis of Ambient Water Temperatures in conowingo Pondr pre-op versus Post-op hourly confidence limits are utilized to detect exceptions to present water quality criteria.

2 Station 13 versus Station 2 3

Station 2 versus Station 18 4

station 13 versus Station 18 Station 13 is located slightly above Pa./Md.

State Line; Station 2, about one mile upriver of PBAPS Station 18 is located slightly below Holtwood Dam, about six miles upriver of PBAPS.

Analysis of dissolved oxygen in conowingo Pond versus Post-op.

1-7 Pre-op

I 1*

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5 Average of samples from top ten feet.

6 Bottom samples Predictive equations are developed based on the preoperational data and the utilization of a control station which are the foundation for distinguishing_ PBAPS effects from natural varation in the post-operational period.

The justification to determine effects of PBAPS operation by developing dissolved oxygen predictive equations for top ten feet and bottom depth is also provided.

Also, each report includes an estimate of the cause and effect relationship between Conowingo Pond water temperature and dissolved oxygen.

Analysis of chlorophyll ~ (TOTAL in Conowingo Pond -

Pre-op versus Post-op.

Predictive equations are developed ba~ed on preoperational data and the utilization of a

control station which are the foundation for distinguishing PBAPS effects from natural variation in the post-operational period.

8 Relationship between chlorophyll (TOTAL) in Conowingo Pond and water flows and temperatures at Holtwood Dam -

Pre-op versus Post-op.

This report provides an estimate of the cause and effect relationship between Conowingo Pond water temperature and chlorophyll s (TOTAL)

• 9 Analysis of Plant Pigments and Water Chemistry The justification for using the average of chlorophyll

~

(TOTAL) samples from surface, 5 feet, 10 feet, and bottom depths is provided in this report.

This report also includes the analysis of variance to detect difference in stations and depths for 7 plant pigment parameters and 16 water chemistry parameters.

Analysis of total zooplankton densities in Conowingo Pond Pre-op versus Post-op.

10 June -

October 11 January -

December 1-8

~ f.

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f.

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Again, predictive equations are developed based on preoperational data and utilization of a control station whic~

are the foundation for distinguishing PBAPS effects from natura~

variation in the post-operational period.

Relationship between Total zooplankton Densities, Diversity, Biomass, and Equitability - Preoperational Period 12 June - October 13 January -

December No meaningful predictive equations could be developed for the Diversity Biomass and Equitability Index parameters which would be used as the foundation for distinguishing PBAPS effects from natural variation.

This report records the efforts to date.

Relationship between total zooplankton densities in Conowingo Pond and water flows and temperatures at Holtwood Dam Preoperational Period.

14 June - October 15 January -

December These reports provide an estimate of the cause and effect relationship between Conowingo Pond water temperature and total--.

zooplankton densities.

Analysis of Benthos Densities and Biomass in conowingo Pond -

Preoperational versus Postoperational 16 June -

October 17 January -

December Covariance analysis, station rankings and Duncan New Multiple Range Test compare preoperational with postoperational benthos communities for total densities and biomass as well as for density and biomass of selected species.

1-9

~I I'

1. 1 JUSTIFICATION FOR THE CONCLUSION TH~T THE PRESENT COOLING SYSTEM AT PEACH BOTTOM ATOMIC POWER STATION, IS SUFFICIENT TO ASSURE THE PROTECTION AND PROPAGATION OF A BALANCED, INDIGENOUS COMMUNITY IN CONOWINGO POND.

In Section 7.0 which describes the aquatic communities in Conowingo Pond, it is demonstrated that:

(1)

Aquatic organisms present in conowingo Pond show great seasonal and annual fluctuations in abundance under natural conditions.

No rare or endangered species exist in the Pond.

No species are commercially harvested for bait or food.

(2)

The organisms are adapted to living within a

wide range of temperatures (32 to 94 F) *

(3)

The organisms can recover from a

catastrophic environmental deviation (caused by Tropical Storm Agnes) which indicates that any short term "appreciable harm" is not irreversible.

Even if there were to be any short term appreciable harm (none is predicted), it would not be irreversible.

(4)

(5)

No thermal stratification has been observed in the Pond since 1966.

The water chemistry of the Pond has not been altered as a

result of PBAPS operation.

Variation in the abundance of the phytoplankton community (as measured by chlorophyll

~)

is positively related to water temperature and negatively related to river flow, i.e., an increase in abundance is associated with an increase in water temperature and a decrease in river flow.

water temperature alone accounted for 60.8% of the variation in phytoplankton density.

The availability of nutrients increases as the phytoplankton population decreases; nutrients are available year-round.

(6)

Total zooplankton densities are low (average less than 3

animals per liter) from November through May.

From June through October, the monthly average density has exceeded 100 animals per liter.

A statistical analysis indicated no change in density due to operation of the station.

variation in the abundance of the zooplankton community is 1-10 l l

• • I

' ~

• , ' *,~

'o ": -

i

~*

~

f I l* t l t:

(

r.,

h

• I

~

1, I

related to water temperature and river flow, i.e.~

an increase in abundance is associated with a

increase in water temperature and decrease in rive1 flow.

More than 75% of the variation in density of zooplankton is explained by water temperature and river flow.

The production of zooplankton and phytoplankton decreases substantially at temperatures less than 600F.

Post-operational studies have indicated that no changes have occured in phytoplankton populations.

(7)

Macrophytic aquatic plants are not common in the Pond.

A small bed of water willow

(~Q§~icia americ2n~)

which is located about 3/ij mile downstream from the Station is the only bed of aquatic macrophytes which is contacted by the thermal plume.

No deleterious effects have been observed on this bed since the start of operations.

(8)

The benthic community in the Pond is sparse.

A small number of species account for most of the individuals.

The common benthic types are oligochaetes and chironomids.

Of the selected representative

taxa, Hg~2ggn!s

!!IDEs~

is infrequently collected; its density never averaged more than 0.01 per 81 in.2 at any monitoring station in any month.

The other selected taxa,.........

f.!:Q£ladiy§ sp.,

~hironQ!!!Y§ sp.,

Ch~QQQ~!!§ __

EgnQti~nn!§ and

~!!!JnQQf!lu§ h2!fm~is~~fi are widely distributed in the Pond.

Their densities have varied between stations and years.

The density of ~.

PYn£tip~nni§ decreased at station

605, immediately downstream from the jet discharge after PBAPS began operating.

~-

hQffmgis~~fi and f~Q£!ad!Y2 sp.

increased in abundance at Station 605.

Postoperational studies have indicated that no changes have occurred in benthic populations with the exception of the immediate vicinity of the discharge.

(9)

The common fishes in conowingo Pond are the white

crappie, channel

catfish, bluegill, pumpkinseed, and spotfin shiner.

Game fishes such as the

walleye, largemouth bass, and smallmouth bass are uncommon.

The gizzard shad was accidently introduced in 1972 and may become a

serious competitor with the desirable fishes.

The bluntnose minnow is not common in the areas which 1-11

r i

• f may be impacted by Station operation.

The com.~on fishes are widely distributed.

Variations in year J\\

class strength have been noted for the common I

species since 1966.

This has been determined by the use of many types of gear at a

number of monitoring stations.

(10) The selected representative species feed, grow and reproduce over a wide range of temperatures.

Most growth and feeding activity occurs from June through October.

Reproduction occurs primarily from May through July.

No differences were noted in the feeding habits, growth and reproduction in

\\)

the postoperational period.

(11) The preference and avoidance behavior of fishes is a

very important factor which will govern their distribution in relationship to the heated discharge.

Upper temperatures tolerance limits are not applicable since fishes will not be trapped in the thermal plume or the discharge canal.

(12) Fishes were collected in the thermal plume; 29 species were taken in the plume by trap net in the period July 1974-March, 1975.

Samples were taken when PBAPS was operating at various power levels up to full power.

Fifteen species were taken in the discharge canal where the fishes were subjected to the highest delta T, the highest water velocity and the greatest fluctuations in temperature which have occurred during the operation, shutdown and start-up of PBAPS.

Fishes were subject to a delta T

as high as 14°F in the plume close to the jet discharge and slightly higher in the discharge canal.

Between July and December, 1974, 31 species were captured in the plume by trawl.

More species were collected in the plume at stations where there was an increase in temperature than those where both the temperature and flow increased.

The catch per effort in the plume was twice as great as that at the periphery and five times greater than that at a control station (located upstream).

Fishes were taken in the plume in all months.

Fishes were trawled at a delta T as high as 140F.

1-12

(13) Natural mortality of fishes has been observed i~

the Pond since the study began in June, 196 Primarily channel catfish and white crappie wert ***

observed.

Mortality is attributed to the bacteria,

~.§!:QIDQ!ls2 sp.

(14) Experimental studies have shown that fishes found in the Pond can withstand a sudden decrease or increase in temperature of up to 15-17°F.

( 15) No fish kills have occurred in the discharge canal

(/

or thermal plume from PBAPS operation at any time including shutdown and start-up.

(16) The winter fishery is restricted to a small portion of the Pond at the mouth of Broad, conowingo creeks and Funks Run.

It is anticipated that this winter fishery will expand to include the area of the Pond heated by the thermal plume.

Extensive field and experimental studies of the organisms in Conowingo Pond have shown the relationships between water temperatures and their effect on biological activity.

Increases in temperature result in increased productivity.

The organisms in the Pond have experienced the temperature range predicted (Elder, et.

at.,

1973) under the "worst case" conditions in sununer.

The fishes and other organisms found i.-....

the Pond have, primarily, a more southern geographic distributio.

and throughout their range may be exposed to natural water temperatures in excess of 930F.

In winter, production in the Pond will be enhanced by extension of the growing season.

Experimental studies supported by field observations at PBAPS have shown that fishes in the Pond can withstand the predicted increases and descreases resulting

~rom start-up and shutdown of the Peach Bottom Station Units No. 2 and 3.

No mortalities are expected and none have been observed to occur due to thermal shock in the plume or discharge canal.

The effects of increased temperature on the biology of fishes will be determined primarily by their behavioral response (preference and avoidance) to various isotherms.

It is the conclusion of Ichthyological Associates that the findings which are summarized in Section 7 provide the basis for predicting that the operation of PBAPS on an open loop cooling system with 3

'helper' cooling towers will assure the protection and propagation of a balanced, indigenous conununity.

The findings to date support predictions made by Raney (1973) 1-13

I,.

relative to the effects of the operation of the Station as designed (with an open cooling system).

The expected effects of the operation of the Peach Bottom Station are given in Section

1. 2.

1.2 EXPECTED EFFECTS OF OPERATION OF THE PEACH BOTTOM ATOMIC POWER STATION UNITS NO. 2 AND 3 1.2.1 Water Temperature 1.2.1.1 Natural Water Temperature Examination of natural water temperature illustrate the wide range of temperatures experienced by the biota in the Pond.

If they were not adapted to living under such variation they could not survive.

None of the biota needs to experience temperatures in the range of 32°F or slightly higher in order to satisfy the needs of their life cycle.

All of the species found in freshwater in the latitude of conowingo Pond are able to exist at winter temperatures of 32oF.

some fishes which are normally found in the shallows in summer become inactive in winter; iri early April or May when the water again reaches approximately 40-sooF they enter shallows.

Temperatures as high as 90°F have been recorded during the pre-operational monitoring period at the surface in Conowingo Pond (July, 1966).

In a

pool located in the shallows below Holtwood Dam a temperatur~ as high as 94°F was measured on 4

July, 1966 when the river flow was 5,700 cfs.

The maximum bottom temperatures recorded in Conowingo Pond during the pre-operational period was 85.2°F in July.

The 7

day average maximum natural temperature for Conowingo Pond (31 years record at Holtwood Dam) for June through August is 87-88°F (Moyer and Raney, 1969. p. 1133).

The average temperature of water entering Conowingo Pond over a

31-year period at Holtwood Dam was:

36.0°F in December, 35.2 in January, 35.8 in February and 39.8 in March.

In April, temperatures ranged from 370F to 70°F (average 49.9).

During the same period, November temperatures ranged from a minimum of 33 to Q maximum of 640F (average 47.7).

1. 2. 1. 2 Model predictions of "Worst Case" Water Temperature conditions Model studies were conducted by Alden Research Laboratories and analysed by Bechtel Corporation, Elder, et.

al, (1973) to predict the thermal conditions in the Pond as a result 1-14

of the operation of PBAPS.

The 11worst case" conditions, occt~

when river flow is low (1675-3350 cfs).

These "worst cas-:.

conditions are based on a theoretical model and have not been verified.

These predictions are presented as references to this document to be used as an upper limit on

~he magnitude of the thermal impact which might occur under normal operation of PBAPS during various meteorological and hydrological conditions.

The predicted 11worst case" summer condition would be when the average flow is 2500 cfs in July and the average weekly incoming temperature at Holtwood is 85°F.

At this time a delta T of sop may occur at the surface, S°F ~ay occur at 10 ft and 2°F may occur at 20 ft.

Under these conditions the maximum temperature predicted at the surf ace may be 93°F and a maximum at depth of 20 ft may be approximately 87°F.

The volume of the total pond water above 87°F under these conditions would be approximately 20%.

It should be emphas*ized that based on 30 years of temperature and flow records only 2.8% of the time was a flow less than 5000 cfs experienced with tempera~ures greater than B0°F (Section q.5).

During the period from November through March, should a low flow occur, the model predicts much of Conowingo Pond downstream from the discharge to a depth of approximately 20 feet may have a temperature increase of at least 10°F.

From late February through early October the delta T in Conowingo Pond wil~

be less and the plume will be smaller.

These increases del~a are due to reduced cooling tower efficiencies during win~e~

months.

From November through January increases in temperature of more than 5°F may occur over a large portion of the Pond.

When the ambient is

350F, a

temperature of 50-55°F might be expected at the surface and a temperature of approximately 45°F may occur at the bottom.

When ambient is 4SOF the temperature in a

large area of the Pond may be as high as c0-63°F at the surface.

In March, with an ambient of 40°F, the oredicted increase in temperature in the Pond is less.

~t an ambient higher than S0°F, the delta T throughout the Pond is expected to be much less than at lower ambient temperatures and the plume will be considerably reduced in size.

Thus the biota will not be exposed to temperatures unusually higher than those which they have experienced as normal annual variation.

1.3 DISSOLVED OXYGEN AND WATER CHEMISTRY The dissolved oxygen concentration in the intake water from conowingo Pond is at or near the saturation level.

The 1-15

r N

I~

r heated water that is discharged is aerated as it passes through the cooling towers and into the discharge canal.

The available BOD data indicate that large amounts of organic wastes are not found in the water.

~.

Studies in 1974 during partial detected no change in oxygen concentration.

other water quality parameters measured range of the preoperational exp~rience.

op~ration of PBAPS The values for the were also within the In a study supported by the Environmental Protection Agency to determine the effects of thermal discharges on water quality and eutrophication, Lee and Veith (1971) suggested that intake water would have to contain large amounts of municipal and/or industrial wastes and be exposed to elevated temperatures for periods of many hours to days before the exertion of BOD would critically deplete the dissolved oxygen in the recP.iving water.

They also stated that "where the intake waters do not contain large amounts of organic wastes or are already at critically low oxygen levels, the effect of using the water for cooling purposes probably would have little or no effect on the amount of dissolved oxygen in the water".

The operation of the Peach Bottom station will have lit~le effect on the concentration of dissolved oxygen and BOD under the "worst case" temperature conditions.,

~.

.;~. ':.. *:... *\\

\\

Thermal stratification (a decrease in temperature of 1°c l per meter) will not occur in Conowingo Pond as a result of the 1 operation of PBAPS.

stratification will not occur because of the i large amount of water exchange (turnover time) as a result of the I operation of the Conowingo Hydro-electric Station and the Muddy

)Run Pumped storage Generating Station.

With the lack of thermal 1 stratification oxygen will not be depleted in the water column because no thermocline will be formed.

The discharge of chlorine to the Pond will be less than 0.1 ppm or le *ss.

This level would be immediately reduced in the plume so that the amount of chlorine would be miniscule.

No significant effect on production of fishes or zooplankton will occur.

1.4 PHYTOPLANKTON COMMUNITY Studies show that temperature accounts for much of the variability observed in the phytoplankton community (as measured by chlorophyll s concentrations)

• The analysis of the relationship of the effect of nutrients, river flow and water temperature indicates that temperature is an important factor in 1-16

'~ ';

• .,/ ';-

.. I *

~

I

~ * * ~,

the production of phytoplankton.

As water exceeds 60°~

phytoplankton production is enhanced.

This will occur betwee November and April at times when PBAPS is operating.

The nutrients are available to support the predicted increase in production during these months

• 1.5 ZOOPIANKTON COMMUNITY zooplankton production in the Pond reaches a maximum at the time of maximum water temperature.

There is no evidence ~hat summer maximum temperature is a limiting factor.

A comparison of density during preoperational and postoperational periods shows no significant effects of the operation of PBAPS on the zooplankton community.

No significant differences in the density were noted at monitoring stations within the plume when PBAPS was operated at full power.

A statistical analysis indicates that an increase in water temperature (along with increase in phytoplankton) stimulates production of zooplankton and an increase in river flow would depress zooplankton (and phytoplankton) abundance.

Since sharp decreases in zooplankton density occur at temperatures less than 60°F, it is expected that when the water temperature exceeds 60°F zooplankton production will be enhanced.

At a water temperature less than 6QOF, no deleterious effects on zooplankton community are expected since the density is normal!~

low (less than 3 organisms/liter).

1.6 BENTHIC COMMUNITY The benthic community consists mostly of chironomid larvae and oligochaetes which make up over 93~ of the population by number.

The species in the Pond can live within a temperature range of 32 to 90°+F and tolerate wide temperature fluctuations.

samples from the discharge canal revealed the presenc~ of the following selected taxa:

H~xa~ni2

!i~Q2~~L

~imnQg~ily2 hoffmei§~~~!, and PrQ£!2dig~ sp. (complex).

The temperature in the canal was 790F and at the intake (60.5°F).

The fact that these taxa are present in the canal suggests that they can withstand high delta T

(1B.S°F).

Their distribution is not restricted by the thermal discharge.

Published information on the temperature tolerance of the benthos common to Conowingo Pond is sparse.

Langford (1972,

p.

331-332) reviewed the effects of power stations in Great Britain and reported that few benthic species are restricted by warm water discharges.

He reported that bimnod~ily2 ho££mgisteri 1-17

1.

j

• {

can reproduce successfully over a temperature range of 5-Jo 0c (41 to 84°F).

He found a large number of sexually mature specimens of L. hof fmeisteri downstream from a heated discharge (in Great Britain)~where-"-the average temperature increment downstream was 10°c (18°F).

In the summer, the plume will not impinge on the bottom of the Pond except over a few acres for a short period under the "worst case" condition (2500 cfs flow and average weekly incoming temperature of asoF at Holtwood).

The temperature increase alone will not harm the benthos in summer.

Some change in benthos has occurred in the immediate scoured area near the discharge in 1974.

Qh~QQQ!~§ P:!:!IlCt!pgnni§ which was commonly taken here before PBAPS operation, was not taken in the latter half of 1974.

~hem~uto2§.Ychg sp.

which was not taken in the Pond earlier was taken for the first time after operation began.

Expected increases in temperature in winter will not have a deleterious effect on benthos.

Observations indicate that emergence takes place at temperatures as low as 49°F in November for two of the most common emergent

forms, PrQcladi~2 sp.

(complex) and

£~!otaD.Y£US £QD.£.in!l!:'!§ (Robbins, et al., 1974, p

• 13).

For £h~QQQ!~§ £!Yl£~~pennis, emergence does not occur until the water temperature reaches 660F and takes place mostly from July through August.

Small shifts in emergence time will not be disruptive to the life cycle of the common emergent benthic taxa.

Any decrease in availability of benthic organisms as food for fishes would be compensated for by an increase in zooplankton productivity.

1. 7 FISHES 1.7.1 Introduction It has been demonstrated that 11worst case" summer temperature conditions are not an unseasonable temperature regime for fishes and other aquatic organisms in the Pond.

However, in the winter fishes and other organisms may be exposed to unseasonable increases in temperature.

The biology of organisms over a temperature range of 50-6QOF (November through February) is the important consideration in the operation of PBAPS during the winter. It is expected that this will be the thermal regime when the temperature of water entering the Pond from Holtwood is between 32 and sooF.

At this time such a temperature regime may occur over a large portion of the Pond.

A synopsis of the findings on the relationship between temperature and fishes in Conowingo Pond follows. It is based on 1-18

• • • ~. r...,.

the findings reported herein and supporting documents.

Robbins~

Euston, Wahl and Mathur (1974) have documented the relationshi.

i between abundance of food organisms, fish food habits, and water,...

temperature.

The fishes which are found in Conowingo Pond are, for the most part, classified as warm water fishes and have a

wide distribution from south-eastern United States to Canada.

They are capable of living and prospering under the various water temperature regimes found through hundreds of miles of their geographic range.

The channel catfish and white crappie which are the two most common fishes in the Pond have been (along with largemouth bass, smallmouth bass, bluegill, pumpkinseed, walleye, yellow perch, white crappie, brown bullhead, yellow bullhead, and golden shiner) transferred to warm water reservoirs in California (Calhoun, 1966, p. 312, 332, 354, 375, 402, 423, 426,

440, 463, q19 and 488) where they have adapted to a winter temperature regime which is warmer than that expected in conowingo Pond with the full operation of the Peach Bottom Units 2 and 3.

Most are native to or were introduced in reservoirs in Alabama and elsewhere in the TVA system.

1.7.2 Temperature Requirement of Fishes Fishes are "cold-blooded".

The body tissues quickly change to the temperature of the surrounding water because the gills must be exposed to permit the passage of oxygen and carbo,.......

dioxide.

Fishes can perceive minute differences in temperatur~

of much less than 10F.

Lethal temperatures are avoided by motile aquatic organisms.

Thus, fishes avoid the hotter part of plumes.

Fishes have a lower and an upper lethal temperature limit or tolerance.

The lethal temperature is specific for each species.

These limits permit adjustment to differences in seasonal temperatures as well as of thos~ of 5 degrees F or more locally, from place to place, from day to day, or night and day.

The lethal temperature is that temperature at which a fish dies after a given time.

Fishes acclimate to a

given temperature, within the lethal limits, and do so regularly with temperature changes accompanying the seasons.

A fish, when permitted to acclimate, chooses a final preferred temperature.

A

species, which is acclimated to a given water temperature may move toward, or away from, a higher or lower temperature.

Once acclimated to a given temperature, fishes acclimate more readily to an increase than to a decrease in temperature.

1-19

r i

The rate of activity of fishes usually increases with a rise in temperature.

However, the relationships may be reversed.

It has been shown that fishes can and will follow a temperature gradient.

They normally follow this gradient to or toward their preferred temperature.

The behavior of a

given species often depends on the magnitude of. change of temperature to which it may be exposed.

It may be attracted to a higher or lower temperature, or it may avoid higher or lower temperature, or it may not react.

obviously lethal maximum temperatures for motile organisms are inappropriate to predict the effects when such species encounter higher temperatures (plumes) because such a measure ignores the behavior of the organisms and the time which an organism might be in contact with such a temperature.

It is proper to use such a

measure only for organisms which cannot avoid and which remain in the increased temperatures.

A far more appropriate measure is the upper avoidance temperature.

Fishes do not normally react to the change of water temperature up to soF.

Changes of more than 7-SOF may and often elicit an avoidance reaction (see Section 7.3 herein).

When a

fish approaches warm water and if it is not in the direction of its preferred temperature, it turns and follows the gradient which must lead to cooler waters.

1.7.3 Fishes and Heated Plumes Observations at large power stations discharging relatively large volumes of heated water into rivers and lakes confirm the absence or rarity of thermal fish kills or serious biological change.

The effect of the heated effluent at Hanford on the Columbia River was observed on salmon and trout over a 25-year period.

No thermal kills of any significance were observed.

See recent reviews by Nakatani (1969).

In England, Alabaster (1969) made studies of fish mortalities, both in the laboratory and in the field.

He reported that kills under field conditions are extremely rare and insignificant.

Nor have thermal kills or other harmful ecological effects to fishes been observed on the lower Connecticut River in extensive studies of the operations of the Connecticut Yankee Nuclear Power Plant (Merriman, 1970).

Kills are absent even where lethal temperatures are present, at the base of a plume, because fishes under most circumstances will shun these areas.

In winter, fishes will be attracted to the Peach Bottom plume because they will be going toward their preferred 1-20

temperature.

During operation of Peach Bottom Units No. 2 and ~

in winter the water in most of conowingo Pond

~ill be a

approximately 40°F when the temperature of the water enterinq ~

from Holtwood is 39°F or lower.

Fresh water reaches its maximum density at approximately 40°F.

In the plume (near the end of the effluent canal but outside a

small zone of rapid mixing) the water temperature may be as much as 54 to 56°F.

If both Units 2

and 3

should suddenly cease operations the wat~r temperature would fall slowly to the ambient water temperature of 400F or less.

Studies were made on the effects of rapid increases and decrease of temperature on fishes.

The basic design of the studies was to simulate a

complete shutdown of PBAPS.

The potential rate of temperature decrease in the plume during a

shutdown will be less than those decreases used in the shock tests conducted in.the laboratory.

Thus the estimates of the effects from shock studies are conservative and they demonstrate only a very low potential for mortality.

During the actual operation of PBAPS the temperature decreases due to unscheduled shut downs will not be rapid.

It is expected that at least one of the two units will remain operating and no shock will result.

In 1974 no fish kills were observed in }f the Pond or the discharge canal at times of Station shutdown.

1.7.4 Reproduction A

combination of temperature and photoperiod is important in timing of the reproduction in fishes.

The peak spawning for the common fishes in Conowingo Pond occurs when the water temperature exceeds 70°F.

Most of the fishes found in conowingo Pond build nests.

Of the selected representative species only the walleye and gizzard shad do not build nests.

The eggs of both species are demersal and develop on or near the bottom rather

~han in the water column.

Spawning occurs throughout the Pond and primarily along the shoreline.

Large areas suitable for spawning for the selected representative fishes and others are available outside that encompassed by the thermal plume.

One of the primary spawning areas (Broad Creek) would not be affected by t.be heated discharge.

Fishes will avoid areas within the plume which may not be suitable for spawning.

The peak of the spawning period is earlier than the period when the predicted 11worst case" summer maximum conditions will exist.

These facts provide evidence that the heated discharge will not adversely effect eggs and larvae.

1-21

I; observations on the spawning of the channel catfish in ponds at Auburn University indicate that minimum water temperature of 700F ior five consecutive days is needed before spawns occurs (Prather, personal communication).

Bennett and Gibbons (1975, p. 82) found that thermal effluent in Par Pond (Georgia) did not grossly alter the reproductive cycles of largemouth bass from heated areas, as compared to cycles of bass from unheated waters.

The heated area had a maximum temperature of 38.3°c (101°F) and the unheated area a

maximum of 27.2°C (810F).

Temperatures of this maqnitude are not expected to occur in the pond.

The predicted winter conditions in Conowingo Pond are not expected to affect reproduction.

When water en~ering the Pond is S0°F in April the rise in temperature may be approximately s-100F in a relatively small area and primarily at the surface along the west shore just downstream from the discharge.

The study of the development of the ovaries (GSI;gonadosomatic index) in the channel catfish and white crappie in conowingo Pond indicates that at 60°F in the spring development is not a~ a peak.

If some early development of gonads takes place and spawning is advanced by several

weeks, food will be available for larvae (see effects of ~emperature on zooplankton abundance below) *

1. 7. 5 Growth Studies of the white crappie and channel catfish indicate that growth normally ceases-between November through May when the water temperature is below approximately 60oF.

Depending on age, growth may resume in the white crappie as early as late May when water temperature exceeds 100F.

Merriman (1970) reported that large numbers of "skinny" brown bullhead were found in the canal at the Connecticut Yankee Atomic Power Plant, Connecticut River.

These fish maintained themselves in a

fast current and at a high delta T.

Thus, the metabolic requirements were greatly increased and the food supply was limited.

In Conowingo Pond the above situation will not exist because of the restricted entrance to the jet discharge and the rela~ively few fish found in the discharge canal.

1. 7. 6 Food Habits No specific feeding areas for fishes are present in Conowingo Pond; the fishes feed throughout the Pond.

The effects of the thermal plume on feeding of the fishes under the predicted "worst case" conditions in the Pond will be minimal.

This 1-22

I activity occurs over the entire Pond and fishes will move tg..,,_

their preferred temperature where food will be available.

- ~

Studies of the seasonal food habits of the channel catfish, white crappie, bluegill, walleye and largemouth bass

indicate, except for the walleye, a dependence on zooplankton from May through October.

The walleye were observed to feed predominantly on fishes.

Changes in food

habits, food availability or both occur when the water temperature is between 50 and 60°F.

The diet of the above species and brown bullhead, yellow bullhead, white catfish, black crappie and rock bass is primarily made up of benthic organisms and fish from November to April.

The feeding rate decreases in most fishes as water temperature decreases.

The to~al number and volume of organisms per stomach is decidedly less in the winter than in the summer.

Sharp decreases in the density of zooplankton occur at a water temperature less than 60°F.

Benthic organism3 and small fishes are then the primary available food buc fishes feed primarily on benthos.

The change to a benthic diet appears to be obligatory rather than f acultative.

Fishes are expected to continue to feed on benthos in winter except at times when zooplankton production is enhanced by the operation of PBAPS.

1.7.7 Movement of Fishes Tagging studies indicate that the channel catfish sho~

little seasonal movement within Conowingo Pond.

The whit crappie moves seasonally.

Crappie have been 'observed to move into the upper portion of conowingo Pond in the spring but by winter have moved downstream to the mouth of Broad and conowingo creeks.

Fishes tagged in the lower portion of Conowingo Pond in November have remained there through the winter.

These were tagged when the water temperature was approximately 50-SS°F.

It appears that the white crappie which move downstream have started or completed their move~ent by the time the temperature in the upper portion of the Pond is 60°F or less.

The expected increase in temperature in winter as a result of the discharge will tend to attract fishes to the heated plume since they will be moving toward their preferred temperature.

some fish which normally move into the lower portion of the Pond may remain in the upper part in winter.

No anadromous fishes are found in Conowingo Pond and there is little expectation that they will ever be present in large numbers.

If the American shad is present in the future it will move freely during its normal spring and fall migrations.

1-23

I r t

~

~ f I I Experiments and observations with the American shad and other anadromous fishes have shown they readily move under or around heated plumes.

Experimental studies by Moss (1970}

on the American shad were confirmed by field studies in the Connecticut River by Marcy, et al., (1972}.

1.8 TROPICAL STORM AGNES The biota of the Pond experienced sudden substantial increases in turbidity, decreases in temperature and increase in river flow when Tropical Storm Agnes (mid-June 1972) wrought devastating effects.

The effects have been documented in sections 2 through 4 of this report.

Decreases in 'cile abundance of organisms were noted in the period shortly following the high flows (more than 900,000 cfs) and are attributed to the heavy silt load,

scouring, and swift currents.

The populations of organisms have recovered from this natural catastrophe.

The zooplankton and phytoplankton populations were observed to recover some~ *hat shortly after the flood and by 1974 the seasonal pattern of atundance was similar to earlier years.

The fishes have recovered at a somewhat slower rate but year classes of the common fishes in 1973 and 1974 have in some cases exceeded the strength of those prior to 1972.

One obvious effect of the reduction of the fish population as a result of Agnes was an increase in growth rate of the white crappie in 1974.

This is attributed to the decrease in overall population which occurred as the result of the destruction of the 1972 year class.

An increase in growth may have occurred in other species but has not yet been documented.

The recovery of the population is evidence that should the operation of the station be detrimental to the biota in the Pond {such detrimental effects are not predicted),

the biota has the capacity to recover and detrimental effects would not be irreversible.

1.9 PREDICTED WINTER FISHERY Large numbers of fishes may be attracted to the heated plume in the winter.

For all the warm water fishes the preferred temperature is above the water temperature that will exist in the discharge between November and February.

The resulting concentration of fishes could serve as a source of an important winter fishery in conowingo Pond.

This prediction is based on our knowledge of the present winter fishery in the Pond and on studies which report that angling in the vicinity of warm water discharges from steam plants is among the best fishing available.

For example, the Tennessee Valley Authority studies (1969, n.p.)

of fish and fishing at five steam generating plants (John Sevier,

Kingston, Bullrun, Colbert and Johnsonville) have confirmed the 1-24

I, presence fishing.

in the two most of large concentrations Channel catfish and white fall, winter and spring in common. fishes in the Pond.

of fishes and good wint~

crappie are among those tak1 large numbers.

These are th~

Moore and Frisbie (1972) reported on a

sport fishing survey which was conducted from January through April 1970 along a one mile discharge canal of a steam electric station located at Chalk Point, Maryland.

In 20,000 fishing trips, 58,000 fishes representing nine species were captured.

This excellen~ catch was made in the canal at a time when sport fishing on the Patuxent River was negligible.

The fact that more fishing was found in the canal in the winter than in summer and fall indicates the value of an unseasonable sport fishery which can be produced by a warm water discharge.

Marcy (1971) reported on a substantial winter-spring sport fishery in the heated canal leading from the nuclear power plant on the Connecticut River at Haddam, Connecticut.

A total of 18 species was caught.

For additional examples of winter sport fisheries which have been established in heated effluents see Elser (1963 and 1965),

Shearer, Ritchie and Frisbie (1962) and Walker (1954).

1-25

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~-

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1.10 CONCLUSIONS We conclude that there has been none and will be no appreciable harm to the balanced, indigenous community, or to community components which results in such phenomena as the following:

substantial increase in abundance or distribution of any nuisance species or heat tolerant community not representative of the highest community development achievable in receiving waters of comparable quality.

Substantial decrease of formerly species, other than nuisance species.

indigenous Changes in community structure to resemble a

simpler successional stage than is natural for the locality and season in question.

Unaesthetic appearance, odor or taste of the waters.

Elimination of an established or potential economic or recreational use of the waters

• Reduction of the successful completion of life cycles of indigeru:>us species, including those of migratory species.

substantial reduction of community heterogeneity or trophic structure.

1-26

2.1 Unit Loading Peach Bottom Units 2 and 3 are base loaded and operated at their full load, 1065 MWe each, as much as possible.

These units generally are operated at lesser loads only during the startup or shutdown processes.

A normal startup or shutdown sequence will typically take about six days.

Scheduled shutdowns for each unit will be made for maintenance and refueling.

For planning purposes, scheduled maintenance shutdowns may be expected at the rate of one week every two months.

The first refueling outage, which will last about five weeks, should occur about 22 months after initial full power operation.

This initial refueling outage for Unit 2

is scheduled to begin in February of 1976.

This is somewhat longer than the scheduled 22 months.

subsequent refueling outages should be expected at 1q-month intervals.

For planning purposes, forced outages may be expected to shutdown the units a total of one week per four-month period.

The estimated average yearly capacity factor for these units is 80%.

The capacity factor wil~

range between 85%

for the summer months and 60% for the wintei months.

2.2 Circulating Water System The locations of all f~atures of the Peach Bottom circulating water system are indicated on Figure 2.2-1.

cooling water for Units 2 and 3 is provided by three 250,000 gpm (557 cfs) pumps per unit, for a total of six pumps with a capacity of 1,500,000 gpm (3350 cfs).

The operation of these units, as

designed, will meet an effluent limitation which provides that discharge to Conowingo Pond of an average of 12 x 109 Btu/hr. and a maximum of 16 x 109 Btu/hr."

2.2.1 Intake Water is withdrawn directly from conowingo Pond through an intake structure approximately 50.0 ft. in length and parallel to the pond.

The intake is protected from heavy debris and ice flows by 32 sets of vertical steel trash bars.

Approximately 40 ft. behind the trash bars are 24 vertical traveling screens of 318 in.

mesh.

The total intake area was designed to be large enough to maintain a maximum velocity through the screens of

.75 2-1

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i **

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fps at the lowest pond level normally attained, 1oq.s ft.

elevation (Conowingo Datum)

• The cooling water enters two separate intake basins, one for each unit, and travels to the pump intake facility where it is again screened by 3/8 inch mesh traveling screens before being pumped through the condensers.

During its passage through the condensers the water temperature is increased by 20.8° F, at full load, and is discharged into a common basin.

The amount of heat rejected to the cooling water, and therefore the condenser temperature rise, is approximately proportional down to about the 20%

power level (approx.

200 MWe).

This relationship is illustrated on Figure 2.2-2.

2.2.2 cooling Approximately 876,000 gpm of the cooling water is pumped to the three forced-draft helper cooling towers.

The remainder of this warm water passes directly into the q700 ft. discharge canal where it mixes with the water cooled by the towers.

The performance of the helper towers, and therefore the discharge temperature rise, is dependent on meteorological conditions.

The monthly variation in discharge temperature rise is indicated on Table 2.2-1.

Table 2.2-2 illustrates the resultant vari~tion in evaporative losses from the cooling towers and the water body surf ace.

2.2.3 outfall The total circulating water flow is discharged to Conowingo Pond via the PBAPS discharge structure located at the end of the discharge canal.

The discharge structure contains one rectangular nonregulated opening and three regulating gates.

Details of this structure are presented in Figure 2.2-3.

The automatic operation of the three regulating gates maintains the velocity of the submerged jet discharge between five and eight feet per second.

The design of the discharge canal and structure was based on the results of hydraulic and thermal model studies performed at the Alden Research Laboratories.

The intent of these studies was to find a configuration that would minimize recirculation and maximize entrailment of the surrounding water in order to limit the heat affected area of the Pond.

A fishnet is deployed over the non-regulated opening when less than three circulating water pumps are operating *

(

1, 2.. 2.4 Transit Times Transit times of the cooling water through the plant are _,.

given in Table 2.2-3.

Numbers in the first column of this table refer to marked locations on Figure 2.2-4.

The relationship between these times and the temperature rise of the water above ambient is illustrated on Figures 2.. 2-5 and 2.2-6 for average July and Nove~ber conditions respectively.

The time required for the discharged water to return to ambient does not lend itself to simple analysis due to the complexity of the hydraulics of Conowingo Pond.

The pertinent information can be inf erred for a particular set of operating parameters - operatio.1 of the hydroelectric stations meteorologyr river flowr etc. -

from the isotherms submitted herewith.

2-3

Table 2. 2-1 Peach Bottom, Unite 2 and 3 Three "Helper" Cooling Towers

..i T

• Seasonal Variation of Discharge

.* 1 :*

Ambient Condenser lt.T Coolint Twr.

Heat Rejected Discharge AT Water Teinp.(OF)

(QF)

Range

°F) via Discharge (109 Btu/hr.)

(OF)

January 35.0 20.8 6.o 13.0 17.3 February 36.0 20.8 5.0 13.4 17.9 March 39.5 20.8 5,5 13.1 17.5 April 48.5 20.8 6.o 13.0 17.3 May 64.o 20.8 9,5 11.4 15.2 N

I June 72.5

\\J'\\

20.8 10.5 11.0 14.7 July 80.0 20.8 13.0 9.8 13.0 August 79,5 20.8 13.5 9.6 12.9 September 70.5 20.8 10.5 11.0 14.7 October 60.0 20.8 8.5 11.B

'J 15.8 November 45.0 20.8 6.o 12.9 17.2 December 35.5 20.8 4.5 13,7 18.2 Average Annual during Operation 12.0 16.0

• based on average monthly meteorological conditions.

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t:

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ft t:

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Table 2.2-2 Peach Bottom Units 2 and 3 Seasonal Variation of Rate of Evaporative Loss*

Evaporative Loss Receiving Water**

Total Evaporative from C. Twrs. (cfs)

Evap. (cfs)

Loss (cfs)

January 6.1 19.5 25.6 February 6.1 18.8 24.9 March 5.5 22.3 27.8 April 7.3 26.0 33.3 May 15.5 26.2 41.7 June 17.1 30.8 47.9 July 21.2 28.4 49.6 August 22.0 27.8 49.8 September 17.1 29.7 46.8 October 13.8 29.5 43.3 November 6.1 25.8 31.9 December 5.5 23.3 28.8 Average Annual Rate during Operation 11.9 25.7 37.6

• based on average monthly meteorology conditions.

• • calculated using formulae developed in Brady, Edinger, and Geyer; Heat Exchange and Transport in the Environment; EPRI Publication No. 74-049-00-3.

2-6

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I-low d1stance0 2

2 J J 4 4-5 5 -6 f,. 7 7 8 K 9 9 10 10 *II 5 10 To1.. 1 Table 2. 2-3 Circulating water transit time through plant cooling system Dcsctiption Rc:t.:ntinn in intake structure

('m:ulatmg water piping to condcn.;cr Condenser Condcn~cr to cooling tower pond I* nst cooling. tower pond Sel*ond cooling tower pond Piping frum pond to coolinit lower Retention m coulin~ tower Coolin,: tower di,char11c to canal Tran,11 m d1wharge canal Hypassini: or cooling tower, time in dischJrge canal Flow d1recll~*

to di~chargc canal 24.3 mm 0.7 mm 14,c,*

1.3 min 38.9 min 22.6 min SH min uPumh l through 10 are labeled llll Fitz. 2. 2-4 2-7 I* lmv through

.:oolin~ toWl'T

.*ystcm

~4. 3 111in

0. 7 min 14 "~"

1.3 min

~4. 3 min

16. 3 min 2::! ~\\*,;

64,c, 111.5 sec 3!1.9 min-109 min

~ I I t

p I' I l f

{

FIGURE 2.2-1 SOUTH

~OOKV

$UBS1ATION COOL1'4C TOWER PUr.IP s T Aue TIJRE N aw1NGO co PONO

~.z-EMERGENCY COOLING TOWER STRUCTURE SCALE o ___

5_o._o __

• o.... oo FEET CLOSEUP OF PEACH BOTIOM COMPLEX 2-9

PEACH BOTTOM UNITS 2 AND 3 Condenser tl.T VS. Unit load

~

I.

22 20 20.8 O; 1065 MWo

~...

16 u...

14

~ 12

°'

10 z....

0 8

z 0 u 6

4 2

j*.

0 0

100 200 300 400 500 600 700 800 900 1000 1100 UNIT LOAD ( M'fh )

FIGURE 2.2-2 2-10

~Pm. t < =* *-* "' -*=<~>U"~>>S¥~~~~*

• -~~~,~-~~~~~

-~~~(~4~~~~~~~~~~~~~~~-*~~~~~~~~~~~~~~~~~~~*~

• ~~**

N I

I-'

I-'

EL 129.0 ft NORMAL WATER EL 108 5 ft LOW WATER EL 104.5 ft EXTREME LOW WATER EL 99.5 ft,,

~;~TTO~ ~~- ~l~C-H~:.R..:.*G.:*E~&!lif.BE~~;.=:::::;::::llim~r-*

CANAL EL 85 0 ft SECTION A-A DISCHARGE STRUCTURE EL 1085 tl NORMAL p(JOL **. *. _ *.

1.-----

REGULATING GATES NO I, 1311 6on HIGH, 20ft WIDE NO 2, 1311 600. HIGH, 2011 WIDE NO 3, 12 It 0 on HIGH, 20 ft WIDE NONREGULATED OPENING 15ft X 201t (aELOW GATE N0.31 GATES REGULATE DISCHARGE vELOCIT'I' BETWEEN 5 AND e fpa FIGURE 2.2-3 Submerged discharge faci1fcy, with details of movable gates.

' )

• 1

N I

N Figure 2. 2-4 Path of cooling water from Conowingo Pond throu2h the Peach Botcom Station. Transit times are given in Table 2.2-3.

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. *.. ~

-~... *.

22.

20 18 16 14

I 12 10

=e 8

6 4

2 0

0 10 20 PEACH BOTTOM UNITS 2 AND 3 Temperature

• Time Plot Average July Conditions

---

----v 876,000 9pm 624,000 gpm /

lo discharge canal I

I I

through cooling low1rs I I 1

I I

1' 30 40 so 60 70 80 90 100 110 TIME ( MINUTES )

Figure 2.2-s 2-13

PEACH BOTTOM UNITS 2 AND 3 Temperature

• Time Plot for Average November Conditions I

I 22 r

i 20 l:

18

~ ;.

16 f

to discharge canal I

L

k.

I' 14 w...

I 12 l

10 0..

2' r

~ /;

8

[t.

u 6

~-

w 4

I.

876,000 gpm through cooling towers f* '

~

2 0

0 r:

20 110 10 30 40 60 70 80 50 90 100

?

TIME ( MINUTES )

~ ~ :

Figure 2.2-&

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2-14

Chemical and Water Quality Data

2. 3. 1 Chlorine The major portion of chlorination will take place in the condenser cooling water system (1.500 1 000 gpm total water flow for both units) but chlorine will a"l:so be added to the service water system (50,000 gpm).

There are six circulating water pumps and each condenser of the two generating units is divided into three sections.

Chlorination will be scheduled to add chlorine to one section at a time.

Basicallyr the amount of chlorine periodically added is determined by checking the effluent from a condenser section to maintain a free residual chlorine of 0.5 ppm.

Maximum rate of chlorination is expected to result in 5 ppm initial charge (to result in 0.5 ppm residual) or a rate of 3,840 lbs/day total chlorine added to both condenser cooling and service water.

This is based on chlorinating each condenser section three times per day for 20 minutes per time plus proportional chlorination of the service water.

At 0.5 ppm residual, the free chlorine to the plant discharge canal and ultimately to the conowingo Pond equals 385 lbs/day total.

However, due to programming the chlorination, the quantity of chlorine added at any one time equals approximately 210 lbs. (based on 5 ppm) or at 0.5 ppm residual~

about 21 lbs.

to the discharge canal.

This residual is rnixe\\

with the total circulating water of 3r450 cfs for a

resultant ~

concentration of less than 0.1 ppm to the pond at any time.

our consulting biologists, Ichthyological..Associatesr has recommended this chlorination schedule to achieve maximum dilution and foresees no adverse effect on the Pond due to this discharge.

Norma11y, the plant would chlorinate at a rate of 2 ppm instead of 5 ppm which would reduce all chlorine quantities to 40% of values shown above.

There is no data available for chlorine demand of the intake water; we estimate it to be about 1 ppm.

2.3.2 Other Chemicals, etc.

Other chemicals, additives or other discharges which are contained in the cooling water are listed in Figure 2.3-1.

These releases, which occur on a frequent (several times/day, are to the discharge pond or canal and are sufficiently mixed such that they may to be continuous discharges.

2-15 batch basis the discharge be considered

r I

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i' Sodium sulfate is the major constituent of the total dissolved solids and therefore was used in the following calculation; concentration of other constituents are insignificant.

330,000 pounds/year pounds

=

904 365 days/year day Using the condenser circulating water flow rate of 1.5 x 106 GPM (18 x 109 pounds/day) the concentration of sodium sulfate in the plant discharge is:

904 pounds/day

=

0.0502 ppm 18 x 109 pounds/day 2-16

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I......

-..J CHEMICAL Calcium Hypochlorite Lime Unidentified Chemical wastes Soda Ash Sodium Hypochlorite Sodium Phosphate Sodium Sulfite S ~ )urn Sulfite TABLE 2.3-1 CHEMICAL DISCHARGES IN COOLING WATER USE Sewage Plant Waste Water Treatment Waste Watec Treatment Sewage Treatment Auxiliary Boilers Auxiliary Boilers ESTIMATED RELEASES (Pounds/Year)

)

3,000 10,000 4,200 30,000 6,000 500 330,000 500 REMARKS Includes chlorides Laboratory Drains Including Water Includes Chlorides Product of Dernineral-izer Regeneration

)

3.0 PLANT OPERATIONAL EXPERIENCE TO DATE 3.1 Generation and Shutdowns Since September of 1973, there has been power produced at PBAPS.

In February of 1974 the initial checkout of Unit No. 2 was completed and the unit began producing power at significant levels (>10%) up to 100%.

In August of 1974, Unit No. 3 began producing power at significant levels.

For this reason, thermal surveys conducted in the Pond from February 1974 to the present are discussed in this document.

Table 3.1-1 contains a

listing of this maximum and approximate average power generated (200% indicates full power of Units No. 2 and 3) by month beginning with February 1974.

PECo monthly report nos.

8 through 23 on the thermal and biological monitoring programs have been included with this submittal as references to provide detailed plant operating data.

3.2 Biological Effects of Shutdowns There have been no mortalities observed in conowingo Pond or in the PBAPS discharge canal due to (during or after) shutdowns.

section 7.2.3 provides a detailed discussion of the biological monitoring programs conducted in the thermal plume.

3-1

.1*1 "

TABLE 3.1-1 PBAPS AVER.AGE AND MAXOOJM GENERATION BY MONTH FEBRUARY, 1974 THROUGH MAY, 1975 PBAPS POWER (in percent)*

MONTH, YEAR AVERAGE MAIDmM February, 1974 11%

34%

March, 1974 13 40 April, 1974 43 79 May, 1974 55 95 Jure, 1974 65 100 July, 1974 88 100 August, 1974 96 100 -,

September, 1974 91 125 October, 1974 105 175 November, 197 4 120 190 December, 1974 135 195 Jamary, 1975 86 200 February, 1975 110 200 March, 1975 191 200 April, 1975 177 200 May, 1975 137 200

'*200% equals :max:ilnum power for both Uni.ts 2 am 3

'"°" '

3-3

4.1 River Flow The watershed of the Susquehanna

River, Figure q.1-1, encompasses an area of about 27,500 square miles.

The main stem, which has its headwaters in New York State, is joined by the West Branch at Sunbury, Pa. and then flows southeast 123 miles to the Cnesapeake Bay.

The river is regulated by twelve existing flood control dams on its major tributaries and by the York Haven, Safe Harbor,

Holtwood, and conowingo Dams and the Muddy Run Pumped Storage Station.

The lower portion of the Susquehanna

River, with the locations of these major dams, is shown in Figure 4.1-2.

Peach Bottom Atomic Power Station is located on the westerly shore of Conowingo Pond just north of the Pennsylvania-Maryland border.

River flow statistics for any particular loca~ion in the lower Susquehanna River are normally based upon flows measured at the USGS gage at Harrisburg.

These flows closely approximate the daily inf low to the Safe Harbor reservoir which is located about 38 miles downriver.

Below Safe Harbor the natural river flows are affected by the operation of the hydro-electric dams.

The operation of the four hydro plants on the Lower Susquehanna {Safe Harbor, Holtwood, Muddy Run and Conowingo) is coordinated to obtain the best overall use of the water available.

Based on predicted flows at Harrisburg, the Conowingo Hydro Plant is scheduled to operate so that Conowingo Pond will be full on Monday morning and lowered by intermittent operation through the week to such a

point that it will refill over the following weekend.

During an average week the pond may be drawn down 3.0 to 3.5 ft.

Figures 4.1-3, 4.1-3 to 4.1-5 show graphically the mass flow patterns in the Conowingo Pond resulting from optimized operations at 2,500, 5,000 and 15,000 cfs.

The volume of water entering Conowingo Pond during a week of operation is, in effect, the area under the inf low curves on these figures.

In addition, "natural river flows" are computed daily at the Conowingo Station based on the past day's operating records.

These calculated values account for all aspects of the operation of Conowingo and Muddy Run but are slightly affected by the limited storage at Safe Harbor and Holtwood.

Flow Duration and 7-Day Low Flow Frequency Curves are presented on Figures 4.1-6 to 4.1-10.

4-1

I r

I I

I I i

4.2 Water Temperatures Monthly means and extremes of the average daily water temperature measured at the Safe Harbor Hydroelectric Station, for the period 1936 to 1966 are tabulated on Table 4.2-1.

The range of these temperatures is illustrated on Figure 4.2-1.

4.3 currents currents in the Conowingo Pond are governed by the operation of the three hydro-electric plants (Holtwood, Muddy Run and Conowingo) which either discharge intor or withdraw from, the Pond.

A preopera~ional Current Velocity Measurements survey was undertaken in April, May and August 1972.

~nY~fQnmgn~sl

~~Yi£~

~Q;:eor~ion:..

!l~n!!sf:i 1.21!l:..

4.4 Depth Contours conowingo Pond is approximately 13.5 square miles in surface area and is about 14 miles long.

Its width varies from 0.5 to 1.5 miles. and is 1.3 miles wide at the site.

The total volume of the Pond is about 310,000 acre-ft. of which about 81.000 acre-ft. are in the top 10 ft.

and are usable for generation at Conowingo Hydro Plant.

Pond depths vary from 10 to 20 ft. near the site to about 90 ft. at the Conowingo Dam.

Bottom contours of Conowingo Pond in the vicinity of the Peach Bottom site and vertical profiles at the intake and discharge are presen~ed on Figures 4.4-1 and 4.4-2.

Bottom contours of all but the upper reaches of the Pond are presented on Figures 4.4 3 through 4.4-6.

Th~ silting rate of the Pond has amounted to about 7 ft. in 20 years.

4.5 Flow - Temperature Relationships The river flow and temperature data previously presented indicate that. in general, the highest water temperatures occur in July whereas the lowest flow rates occur in September.

Yearly 7-day low flows and the corresponding average water temperaturesr are presented in Table 4.5-1 for the period 1936 to 1966.

Median 7-Day Low Flows and temperatures during the low flows for each month are listed in Table 4.5-2.

A more conclusive analysis of the coinciden~

relationship between temperature and flow is presented in Table 4.5-3, a joint probability distribution.

The probability of occurrence for any chosen range of temperature and flow can be found directly from this table.

This analysis indicates that while daily water temperatures greater than aoo F occurred 12.7%

of the time these were coincident with flows less than 2,500 cfs only

.06%

of the time and coincident with flows less than 5,000 cfs only 2.8% of the time.

4-2

TABLE

"* 2-1 sm:MARY OF SUSQUEHANNA RIVER TEMPERATURES (Average Daily River Temperature~ at Safe Harbor Hydro Station, 1'?36 to 1966)

~ Feb.

~ !E!::.

~ ~ ~ ~ Sept..

~ ~ ~

¥.ax.

51.0 56.0 73,0 78.0 67.0 84.o 76.0 67.0 50.0 39.0 1936 Avg.

38.5 48.5 69.8 74.1 Bo.6 Bo.5 72.7 Go.9 42.4

]J. 7 Min.

32.0 43.0 62.0 68.o 73,0 75.0 68.o 49.0 34.o 32.0 Max.

43.0 55.0 77,0 81.0 87.0 64.o 82.0 71.0 49.0 43,0 1937 Avg.

37,9 47,7 63.9 77.4 79.8 79.7 70.5 61.4 43,4 34.4 M:n.

33.0 42.0 51.0 74,o 73.0 72.0 64.o 53.0 36.0 32.0 Mo.x.

54.o 66.o 70.0 81.o 84.o 86.o 79.0 65.0 57.0 42,0 1938 Avg.

41.1 53,3 65.3 75.8 79.9 83.3 70.9 60.7 48.9 36.4 Min.

32.0 39,0 59.0 67.0 74.o 78.0 62.0 53.0 33.0 32.0 Max.

50.0 59.0 79.0 81.0 82.0 84.o 78.0 69.0 53.0 40.0 1939

Avg, 40.3 117.8 67.6 78.0 78.6 81.6 73.6 61.0 44.4 36.6 Min.

36.0 40.0 55.0 75.0 76.o 78.0 70.0 54.0 4o.o 32,0 Max.

41.0 54.o 69.0 79.0 86.o 86.o 74.o 64.o 51.o

• 44,0 1')40 Avg.

34. 3 43.9 63.0 73.7 Bo.o 79,3 70.3 58.3 45.2 35,6 Min.

32.0 37.0 55.0 64.o 70.0 72.0 64.0 50.0 36.0 33.0 Max.

4o.o 66.0 77,0 03.0 84.0 84.o 76.0 12.0 55.0 43.0 1941 A.,.g.

34.4 54,o G7.9 74.4 79.6 78.1 74.6 64,7 47,3 31.a Min.

32.0 41,0 64.o 67.0 77.0 72.0 70.0 55.0 43.0 33,0

Max, 45.0 62.0 71.0 79.0 82.0 83.0 79.0 64.o 52.0 48.o 1942 A*tg, 39, 1 51.5 65.8 74.4 79.1

17. 1 74.4 59.2 45,7 34,7 Min.

33.0 43.0 59.0 68.o 75,0 72.0 63.0 49.0 39.0 32.0 Max.

46.o 54.0 67.0 87.0 85.0 84.o 70.0 64.o 52.0 4o.o 1943 Av3.

38. 1 46.1 60.8 77,7 Bo.7 Bo.7 71.6 57.S 43.6 35,0 loli.n.

32.0 41.0 52.0 65.0 76.0 77.0 65.0 48.o J(.0 32.0 Mu.

~3. 0 52.0 75.0 79.0 811.0 85.0 77.0 66.o 52.0 37,0 1944

Avg, 36,5 46.3 65.8 73,5 81.1 80.4 72.1 58.6 45.5 33.0 Min.

32,0 4o.o 55,0 69.0 78.0 74.o 67.0 48.o 38.0 32.0

}'.ax.

59.0 64.o 65.0 83.0 86.o 80.0 79.0 66.o 60.0 39.0 1945 Avg.

43, 1 56.7 58.1 72.4 77.8 76.4 72.2 55.5 46.8 35.8 Min.

32.0 52.0 50.0 59,0 12.0 68.o 61.0 50.0 38.0 3~.o

!-'.ax.

56.0 63.0 68.o eo.o 83.0 ao.o 78.0 68.o 61.0 43.0 1946 t.*1g.

43.9 54.5 62.6 69.2 80.6 76.0 74.0

• o.8 49,5

)£.3 Min.

32.0 48.o 57.0 61.0 79,0 74.o 72.0

• r.o 41.0 32.0 Ma.A.

43.0 54.o 69.0 78.o 81.0 84.o 79,0 i5.0 61.0 37.0 1947

Avg, 35.0 49.6 60.0 70.6 76.5 79.7 73.0 r:i1.9 45,9 33.6 Min.

32.0 40.0 49.0 66.0 10.0 76.0 60.0 58.0 36.0 32.0 Max.

48.o 58.0 65.0 82.0 82.0 87.o

?;1.0 68.o 57.0 43.0 1948 Avg.

40.0 51.0 60.2 73,9 80.2 77-9 74.6 58.6 50.6 37,4 Min.

34.o 46.o 54.o 64.o 76.0 73.0 68.o 51.0 44.o 32.0 If.BX.

57.0 60.C 72.0 82.0 88.o 86.o 79.0 10.0 55.0 39.0 1949 Avg.

42.6 52.7 66.4 76,9 82.4 82.0 70,9 63.6 46.5 35.5 Min.

36.0 46.o 59.0 66.o eo.o 78.0 63.0 56.0 36.0 33.0 Max.

43.0 55.0 67.0 81.0 6o.o 63.0 81.o 64.o 61.0 41.o 1950 Avg.

35,5 46.4 61.2 73.2 78.9 78.0 69.0 59,2 46.8 35.0

!<'.in.

32.0 39.0 52.0 67.0 77.0 73,0 56.0 54.o 37.0 32.0 l'.s.:c.

48.o 62.0 71.0 81.o 83.0 83,0 79.0 69.0 56.0 47.0 J

1951 A-lg.

41.2 50.1 66.4 73.8

&J.7 79.7 73.4 61.7 42.2

36. 1 Hin.

38.0 41*.0 60.0 64.o 76.o 77.0 68.o 57.0 35.0 32.0 Max.

46.o 61.0 64.o 84.0 87.o 85.0 79.0 70.0 52.0 43.0 1952 A";g.

1.c.1 51.4 60.3 75,9 83.6 80.2 74.o 57,9 46.1 37,7 Min.

36.0 45.0 55.0 65.0

?9.0 76.o 69.0 48.o 41.0 32.0 4-3

TABLE 4.2-1

'. ::ontinucd)

~

Sl.if.if.lo\\.RY OF SUSQUEl!A!l?lA RIVER TF.MPE-llATURES i

Jan.

Feb.

~ Apr.

~ ~ July Aug.

~

Qs.h

~ Dec.

f M..u:.

52.0 59.0 10.0 79.0 81.0 82.0 83.0 72.0 64.o tis.a l}"

1'}53 Avg.

ti2.6

51. 1 64.li 71.7 78.B 79.0 74.5 66.5 49.8 38.0 Min.

37.0 44.0 56.0 58.0 76.o 77.0 69.0 64.o 43.0 32.0

~

Ma."C.

50.0 66.o 74.0 82.0 85.0 85.0 78.o 75.0 54.o 39,0

(*

f.

i954

Avg, 41.9 54,7 61.3 75.8 79,6 77,9 73.0 63.0 44,3 33,9 Ii Hin.

36.0 45.0 53.0 68.0 11.0 73.0 68.o 52.0 41.o 32.0 Max.

47.0 61.0 77,0 8T,0 88.o 86.o 78.0 68.o 5ti.o 38.0 fi. h 1955 Avg.

41.5 53.8 68.2 73.4 85.0 8o.6 73.7 60.0 44,8 34,7

~::*

Mi:i.

3a.o 43.0 58.0 66.o 79.0 75.0 67.0 50.0 36.0 3ti.o 1~*

Max.

43.0 59.0 70.0 84.0 82.0 BT.o 82.o 63.0 61.0 43.0

~y 1956 Avg.

39.3 46.5 61.3 76.o 77.0 11.3 70.2 59.0 47.8 40.7 fi*

Min.

3;.o 42.0 57.0 68.0 73.0 73.0 59.0 54.0 36.0 36.0 ii lfa.i:.

47.0 68.o 73,0 88.o 85.0 86.o 79.0 66.o 50.0 46.o

1.

1957 Avg.

42.3 50.5

67. 1 79.0 Bo.5 78.9 7li.7 58.2 46.3 37.fi Min.

36.0 42.0 61.o 72.0 77.0 75,0 67.0 50.0 40.0 32.0 BJ*

Ma.-.:.

45.0 6o.o 70.0 78,0 84.o 81.0 77.0 63.0 52.0 43.0 li1*

1958 Avg.

39.7 49.2 61.5 71.7 So.a 79.3 72.2 58.2 47,3 34,2

r. ~

Min.

34.0 41.0 51.0 66.0 75,0 75.0 66.o 50.0 36.0 34.o Max.

44.0 60.0 81.0 86.o 86.o 86.o 83.0 76.0 52.0 39.0 1959 Avg.

3'~* 1 50.B 67.6 76.3 82.4 82.3 76.4 64.1 44.3 35.8 Min.

33.0 43.0 55,0 67.0 80.o 16.0 69.0 52.0 37,0 32.0 Max.

50.0 10.0 67.0 77.0 82.0 82.o 82.0 68.o 52.0 48.o

~

1960 Avg.

37.li 52.9 61.2 73.0 79.3 eo.5 72.5 60.6 47,3 36.2 Min.

34.0 41.0 53.0 65.0 77,0 79.0 65.0 50.0 43.0 34.o "J Mn.x.

49.0 66.o 82.o 86.o 84.o 84.o 59.0 73.0 59.0 39.0 1961 Avg.

41.5 46.8 60.0 75.3 81.2 ao.2 78.7 62.7 li9.6 35.0

~-

Min.

36.0 41.0 52.0 63.0 76.0 77.0 72.0 55.0 39.0 32.0 11' Max.

50.0 67.0 81.0 81.0 81.0 ao.o 80.o 65.0 49.0 41.0 I"'

.'\\

1962 Avg.

39.2 48.6 69.3 78.4 78.7 77,9 71.9 61.4 43,9 35.7

!~ :

Min.

32.0 41.0 60.0 16.0 76.0 76.0 64.o 50.0 4o.o 34.o Mex.

46.o 61.o 68.o 83.0 86.o 83.0 76.0 65.0 56.0 45,0 lt 1963 Avg.

36.2 52.6 62.9 74.1 79.6 76,7 70.2 63.8 50.3

35. 1 Min.

32.0 44.0 53.0 68.o 75.0 73,0 64.0 57,0 46.o 32.0 1 ;~

Max.

47.0 59.0 74.0 83.0 86.o 83.0 79.0 67.0 55.0 41.0 i:.*

1964 Avg.

41.1 49.4 65.6 75,9 82.2 77.5 74.6 58.9 51.6 36.J l

Min.

34.o 41.0 50.0 68.o 77.0 74.o 68.0 55.0 41.o 33.0 l;,

Max

• 43.0 55.0 74.o 79,0 81.0 8).0 78.o 69.0 51.0 41.0 l '.-' "

1965

Avg, 39.6 49.4 67,5 74.o 78.4 79.2 73.6 59,7 46,5 38.1

i.

Min.

33.0 42.0 58.0 69.0 75.0 73.0 70.0 51.0 42.0 35.0

r.

p Max.

47.0 58.0 70.0 83.0 85.0 82.o 82.o 60.0 52.0 44.o 1966 Avg.

41.2 48.2 59,2 74.2 81.0 78.8 71.5 57.4 46.3 36.~

l*

Min.

J7,0 42.0 51.0 65.0 n.o 76.o 60.0 53.0 40.0 33.0 t

ii*;

I r

\\*

38.0*

70.0 81.0 88.o 88.o 87.0 84.o 76.0 64.o 48.o L.

Max.

37,5*

59.0 Total Avg.

35.2*

35,8*

39.5 50.2 63.9 74.6 80.1 79.3 72.9 60.5 46.5 35,9 L

Period Min.

32.0*

32.0*

32.0 37,0 50.0 58.0 70.0 68.o 56.0 48.o 33.0 32.0 h

from Table V of Peach Bottom Units 2 end 3 Desi!I!:! En~eers ReEort; S~pt, 16, 1968; daily data for Jan.

and Feb. is not presently available,

.82 Flow DistrilJ.!.l~ion

< ~.500 0

.309

.451

.283

.371

.o44 0

1.458%

2,500 -

4,999

.oao

.592 1.175 2.165 5.276 1.856

.177 11.321%

5,000 -

9,999 2.589 1.688 2.033 2.307 5.647 3.889

.247 18... oo,g Ill 13.824%

10,000 - 14,999 4.216 1.441

.831

.954 4.278 1.821

.283 CJ I

15,000 - 19,999 3.818

.919

.486 1.025 2.846

.725

.009 9.829%

l="

0

.-1 I

l&t 20,000 - 29,999 4.940 1.865 1.131 2.165 2.430

.327 0

12.856%

-.J Q) >

30,000 - 39,999 3.526 1.494

.981 1.821 1.087

.018 0

8.92'7%

• .-1 IX:

40,000 - 49,999 2.333 1.370 1.228

.999

.362 0

0 6.29~

50,000 - 74,999 4.030 2.961 2.678 1.326

.194 0

0 11.189%

~ 75,000 2.015 2.298

.972

.583

.027 0

0 5.895%

7-Day Ave. Temp Distribution 27.547%

14.937%

11

• 96f11, 13.628%

22.518%

8.66~

.716%

• based on average daily USGS river flows for Harrisburg and average daily temperatures at Safe Harbor Hydro Station (1936-1966),

=I"':(.**.* *.

I.*

I I,,,.

(;!;:;::::::) DRAINAGE AREA I

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PHILADELPHIA ELECTRIC COMPANY SUSQUEHANNA RIVER BASIN FIGURE 4, I - I 4-9

~.

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HARRISBURG

/.

CRAWFORD GENERATING STATION THREE MILE ISLAND NUCLEAR STATION BRUNNER ISLAND G r:NERATING STATION

---SAFE HARBOR HOLT WOO cf.:---

PEACH BOTTOM PA ATOMIC POWER STAT ION MO.

DOMESTIC WATER SUPPLY INTAKES I. CITY OF CHESTER 2 CITY OF BALTIMORE 3

CONOWINGO VILLAGE 4 BAINSRIOGE NAVAL TRAINING STATION INCLUDING PORT DEPOSIT 5

PERRY POINT VETERANS HOSPITAL 6

HAVRE OE GRACE BALTIMORE 0

10 20 SCALE* MIL.ES CONOWINGO PHILADELPHIA ELECTRIC COMPANY J{

lOWER SUSQUEHANNA RIVER HYDRO PLANTS ANO OTHER WATER UTILIZING FACILITIES (includes thermal generation)

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0o 10 PERCENT Of' TIME FLOWS ARE EOUAU£0 OR EXCEEDED PERIOD: 1329-1969 SOURCE' co.. ow1NGO HYORO PLAPllT PHILADELPHIA ELECTRIC COMPANY FLOW DURATION CURVES SUSQUEHANNA RIVER AT CONOWINGO DAM FJGURE 4.1-6

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90 80 70 60 50 40 RANGE OF AVERAGE DAILY RIVER TEMPERATURES Susquehanna River at Safe Harbor Hydro Station (1936 - 1966)

MAXIMUM"'

AVERAGE J

F M

A M

J J

A S

0 N

0 MONTH

)

FIGURE 4.2-1 4-19

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R(.~.: 'CM',

' t.*,() j Fig 4.4-1 Bottom contours of Conowingo Pond at the Peach Bottom site, with vertical profiles shown for the points of intake and discharge.

Note:

based on 1967 survey.

4-20

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I N.....

300 -

200.

E 100 -

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• • --- IOI :-_: :~ - '. ** - ~..:.* :-

TOPOGRAPHY VICINITY OF PEACH BOTTOM ATOa.!C POWER STAT10H DISCHARGE STRUCTURE h()VEMBtR 19

• 1973

.* -******---*--**- 104 **-..... _

• --. 101 _ _

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The basic meteorological data used for the analysis of cooling tower and pond thermal performance studies were developed from data taken at the site, with the exception of solar radiation which was taken from Climatic Atlas of the United

§!~!g§.

ory-buib temperatures:--reiative--hurnidity;--wet=Eu!b temperatures. and wind speed data were analyzed for the period from August 1967 through March 1972 for several locations and elevations.

The data used for these performance studies are shown in Table 5.0-1.

Table 5.0-1 Pe~ch Bottom Units 2 e.nd 3 Monthly Meteorological Data Solo.r DrJ Bulb Relative llet-Bulb Vind Speed (moh)

P.adi~t.ion Month Occul"!lnc&

Te~2. ~°F}

Humidit:z: m Temll. (°F}

at :zo n.

at 22 rt. CLo.ng1eisLctall J!l.DUary ave.

27.0 75.0 25 8.5 6.7 160 50.'

30 5;£ 4o Fobruar::r ave.

30.0 70.2 27 7.6 6.o 225 50%

30 5%

44 March ave.

38. 1 68.5 34,5 8.2 6.5 315 50%

35 5~

51 April ave.

50.0 67.9 45 8.3 6.6 400 50%

45 5~

62 M""7 ave.

60.o 76.2 56 6.7 5.3 48o 50.'

55 5;.b 68 June ave.

70.9 01.8 67 6.3 5.0 525 5m 65 s:t 73 July 111;a.

75.3 82.1 71 5,5 4.3 510 5~

68 76.0 89.0 74 3.4 610 August ave.

71.8 84.1 68 4.5 3.5 450 50%

68 5~

74 September ave.

62.e 86.7 60.5 5, 1 4.o 38o 51 61 5

73 October ave.

54.3 84.4 52 5,7 4.5 270 5~

50 65 Noveciber ave.

42.9 81.5 40.5 6.o 4,7 160 5m 40 5~

56 December ave, 34.9 78.5 32.5 8.2 6.5 130 5~

30 5;£ 47

--~

I *"

5-1

6.0

6. 1 Predicted Isotherms Temperature distributions in the conowingo Pond resulting from the heat rejection from Peach Bottom Units 2 and 3 have been predicted based on the analysis of physical model studies conducted at Alden Research Laboratories of Worcester Polytechnic Institute.

Tests were conducted to simulate various river flows and associated pond operating schedules, river temperatures and plant operating conditions.

A detailed description of the studies and the resultant predicted isotherms is contained in Elder. et.al. (1973).

Studies of the effect of a sudden plant shutdown are included.

The state-of-the-art in physically modeling and theoretically analyzing thermal problems such as associated with the Peach Bottom project makes exact predictions of temperature patterns impossible.

The ambient pond temperature will vary with fluctuating meteorological and flow conditions.

however, the predicted excess temperature distributions should still be representative of those that will be experienced for the range of conditions studies.

6.2 Observed Isotherms In order to optain an overall analysis of the extent and magnitude of the thermal plume, boat surveys are conducted on a

regular basis.

Selected isotherm maps of the thermal conditions in the Pond during PBAPS operation are provided in Figures 6.2-1 to 6.2-8.

These figures were selected from each season at times when the river flow was lowest and PBAPS power levels were the highest.

In this manner an overview of the "worst case" conditions can be obtained.

All isotherm survey plots have been provided on a monthly basis to the U.S.

Nuclear Regulatory Commission, the Commonwealth of Pennsylvania Department of Environmental Resources and the State of Maryland Department of Natural Resources.

For convenience, they have been resubmitted with this document as supporting references, PECo, Monthly Report Nos. 8 through 23, thermal and Biological Monitoring Programs.

Monthly report No. 13 begins address the biological effects due to the measured thermal impact.

6.3 Plume Velocity Distribution Typical surface plume velocity measurements taken at the surface, 5 ft and 10 ft depths are shown on Figures 6.3-2, 6.3-4 and 6.3-6 respectively.

In order to provide an indication of the 6-1

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I. i t I

~-

~**.

location of the thermal plume, isotherm plots, taken at the same time are given on Figures 6.3-1, 6.3-3 and 6.3-5.

Centerline plume velocity vs. distance from the jet discharge is plott~d on Figure 6.3-7.

6.4 Other Thermal Effluents There are four thermal generating stations on the Susquehanna River between Harrisburg and Peach Bottom (Crawford, Three Mile Island, Brunner Island, Holtwood).

The locations of these stations are shown on Figure 4.1-2 and their rates of thermal discharge are listed in Table 6.4-1.

The excess temperature caused by the thermal effluents of the Crawford, Three Mile Island, and Brunner Island Generating Stations is entirely dissipated by the time the water reaches Peach Bottom even during the 7-Day, 10-Year recurrence low flow.

The Holtwood Steam Generating Station is located adjacent to th~

Holtwood Hydro Electric Station, about 4

miles upstream from Peach Bottom.

Under steady-state low flow conditions, without Muddy Run operating, the thermal discharge from Holtwood could account for as much as 0.5° F temperature increase at Peach Bottom.

However, in reality, the operating cycles of Muddy Run complicate the flow patterns in the upper reaches of the Pond and serve to dissipate this excess temperature before it reaches Peach Bottom.

At low river flows when Muddy Run is pumping (24,000 cf s) river flows are toward Muddy Run from both upstream and downstream.

When Muddy Run is generating (28,000 cfs),

the remaining excess temperature in the Conowingo Pond from upstream is effectively being diluted by flows several times greater than the natural river flow.

Figure 4.1-3 illustrates the order of magnitude of these flows and the scheduling of hydroelectric station operations for 2500 cfs river flow.

Because of the complicated hydraulics and its interrelationship with holding time and dilution, it is impossible to accurately predict what temperature excess caused by Holtwood could be expected at Peach Bottom.

A conservative estimate would be considerably less than the 0.5° F mentioned above.

6-2

Station Crawford TABLE 6.4-1 THERMAL GENERATING STATIONS BETWEEN HARRISUBRG, PA. AND PEACH l30'i"TOM Distance Generating above P.B. (miles)

Capacity (MWe) 39.8 117 Three Mile Island 35.8 1770 Brunner Island 31.8 1454 Holtwood 4.0 73 (thermal generation only) 6-3 Heat Rejected

( 106 Btu/hr.)

831 54 6836 674

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SMALL BOAT SURVEY

SUMMARY

SHEET DATE: Tues. August Oay Month HYDRAULIC DATA Pond Elevation:

20 Date 1974 Year Start 107.45 CFS Average ( 24 Hr} Flows :

Natural River 5,300 CFS Conowingo Dam Draft 9,650 Daily Mean Temperature:

Holtwood 27. 1 oc

( 80.8 OF) f*:id Survey Temperature:

Holtwood 26.5

°C

( 79.7 Of}

SM.!\\LL BOAT SURVEY DATA TIME:Start 0900 Hours (E.S.T.)

Finish_....14-'-4~5 __ Hours (E.S.T.)

Finish 108.18 CFS Conowingo Inflow 5, 125 CFS CFS Muddy Run 26.0 oc

(_78.8 Muddy Run 26. 1 oc c 79.0 Peach Bottom Atomic Power Station: Discharge Water 30.2 oc

( 86.4 OF}*

PBAPS Power:

Thermal Electrical Surface Temperature:

Bottom Temperature:

METEOROLOGICAL DATA Tima:

0900 - 0915 3285.5 1098.1 (Max} 30.2

{Min) 25.9 (Max) 30.2 (Min) 25.6 E.S.T.

Air Temperature:

78

°F Relative Humidity:_7;....;1 __

Precipitaticn:_O _______ Inches (24 Hr Total}

Intake Water 26.0 oc

( 78.'8 OF)*

AT 4.2 c

( 7.6 fO)

Megawatts Megawatts oc c 86.4 Of)

Sta. No. 9 oc

( 78.6 Of)

Sta. No. 68 oc

( 86.4 OF)'

Sta. No. 9 oc

( 78.1 OF}

Sta. No. 68 Location:

Sta. 7 Wind Speed :_2_.a _____

__;mph

\\.!ind Direction: N ------

Cloud Cover: Partly Cloudy COMMENTS:

Survey begun at North end of Pond.

• Average of 5 foot depth increment readings Cooling towers operating = 3 6-4 Of}

Of)

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r I ;

i i

SURFACE INTAkE 79.2 DISCHARGE 86.4 DEPTH 5 FT.

INTAKE 78.6 DISCHARGE 86.4 DEPTH 10 FT.

INTAkE 78.4 DISCHARGE 86.4 79 PLANT POWER : 100 %

AVERAGE COOLING WATER tl!T: 7.7.,

HORIZONTAL SCALE 0

4T AT STATE LINE* 2.5*F (STATE LINE - HOLTWOOD) 6-5 r

u 0

75 FIGURE 6.2 -I HORIZONTAL ISOTHERMS AND THERMAL PROFILE OF CONOWINGO PONO DATE 8-20*74 TIME 0900*1445

O" I

DATE: Sun. October 27. 1974 day month date year TIME:

Survey Start:

1240 Hours (EST)

State Line:

Hours (EST)

Survey Finish:

1730 Hours (EST)

HYDRAULIC DATA Pond Elevation Start:

106.97 Feet Finish:

106.95 Feet Average (24 Hour) Flows:

Natural River 9300 CFS Conowingo Inflow 4875 CFS Conowingo Dam Draft 50 CFS PBAPS POWER OUTPUT Unit 2: Thermal 2993.3 Megawatts Electrical 898.0 Megawatts Unit 3: Thermal 2683.3 Megawatts Electrical 805.0 Me~awatts METEOROLOGICAL DATA Time:

1240 - 1255 EST Air Temperature:~°F Relative Humidity:_§.!L_Percent J

-~

BOAT SURVEY

SUMMARY

WATER TEMPERATURE (THERMOGRAPH)

Daily Mean: Holtwood oc OF)

Muddy Run 10.8 °C 51.4 °F)

Mid Survey: Holtwood oc OF)

Muddy Run 10.9 °C 51.6 "F)

WATER TEMPERATURE (SURVEY}

PBAPS: Discharge 20.0 °C 68.0 °F)

Intake 13.6 °C 56.5 °F)

..6. T 6.4 C 0

11.5 F0 )

Pond Surface:

Station Maximum 20.0 °C 68.0 °F) 9 Minimum 12.4 °C 54,3 OF)

Pond Bottom:

Maximum 20.0 °C 68.0 °F) 9 Minimum 12.0 °C 53.6 °F) 27 Precipitation:

o Inches (24 Hour Total)

Location: Boat Station 7 Wind Speed:

12.0 MPH Wind Direction: ___

No"-'r"""t"""h __ _

Cloud Over:

Clear Co11111ent:

. )

SURFACE INTAKE 56.7 DISCHARGE 68.0 r

DEPTH 5 FT.

INTAKE

56. 5 DISCHARGE 68.0 DEPTH 10 FT.

INTAKE 56.5 DISCHARGE 68.0 CENTER LINE CROSS SECTION 68 67 66 6~

PEACH BOTTOM ATCMIC POWER STATION PLANT POWER: 158%

AVERAGE COOLING WATER IH:tt.4°F HORIZONTAL SCALE 0

aooo IOOO AT AT STATE LINE

• Z.3 °F (STATE LINE -HOLTWOOO>

6-7 0

FIGURE 6.2 *2.

HORIZONTAL ISOTHERMS AND THERMAL PROFILE OF CONOWINGO POND DATE 10 -Z7-74 SUN TIME IZ40 - 1730

a-I CD DATE: Fri. November 15, 1974 day month date year TIME:

Survey Start:

1200 Hours (EST)

State Line:

Hours (EST)

Survey Finish:

1705 Hours (EST)

HYDRAULIC DATA Pond Elevation Start:

106.11 Feet Finish:

104.66 Feet Average (24 Hour) Flows:

Natural River 21,600 CFS Conowingo Inflow 22,825 CFS Conowingo Dam Draft 30,660 CFS PBAPS POWER OUTPUT Unit 2: Thermal 3,230 Megawatts Electrical 1,070 Megawatts Unit 3: Thermal 21845 Megawatts Electrical 990 Megawatts METEOROLOGICAL DATA Time:

1200 - 1215 EST Air Temperature:__1g___°F Relative Humidity: 77 Percent

~J BOAT SURVEY

SUMMARY

WATER TEMPERATURE (THERMOGRAPH)

Daily Mean: Holtwood 9.8 oc ( 49.6 OF)

Muddy Run 10.4 oc ( 50. 7 OF)

Mid Survey: Holtwood 9. 9 oc ( 49.8 OF)

Muddy Run 11.0 oc ( 51.8 OF)

WATER TEMPERATURE (SURVEY}

PBAPS:

Discharge 18.3 oc ( 64.9 OF)

Intake 10.3 oc ( 50. 5 OF)

L'i. T 8.0 co ( 14.4 FD)

Pond Surface:

Station Maximum 18. 3 oc ( 64.9 OF) 9 Minimum g,8 oc ( 49.6 DF) 2 6 Pond Bottom:

Precipitation:

0.20 Inches (24 Hour Total)

Wind Speed:

11. 6 MPH Cloud Over:

partly cloudy

,J Maximum 18. 3 oc ( 64.9 OF) 9 Minimum 9.8 oc ( 49.6 OF)

2.6 Location

Boat Station 7 Wind Direction: north west Comment:

i,'

.......__so SURFACE INTAI<(

.O.ll DISCHARGE 64.9 DEPTH 5 FT.

INTAKE

~O.~

DISCHARGE 64.9 DEPTH IOFT.

INTAKE !10.S DISCHARGE 64.9 60 PLANT POWER : 188 %

AVERA~E COOLING WATER aT: 14.4*F KORIZONTAL SC.AL.I I

I I

I 0

4T AT STATE LINE

• 3.6 *f (STATE LINE - HOLT WOOD) 6-9 FIGURE 6.2 -J HORIZONTAL ISOTHERMS AND THERMAL PROFILE OF CONOWINGO POND DATE 11-15-74 FRI TIME IZ00-170!S

C1' I

0 DATE:Thurs.

December 26, 1974 day month date year TIME:

Survey Start:

1100 State Line:

1255 Survey Finish: 1530 HYDRAULIC DATA Hours (EST)

Hours (t:ST)

Hours (EST)

Pond Elevation Start:

107.04 Feet Finish:

106.35 Feet Average (24 Hour) Flows:

Natural River 33,100 CFS Conowingo Inflow 30,975 CFS Conowingo Dam Draft 33, 100 CFS PBAPS POWER OUTPUT Unit 2: Thermal 3,300 Megawatts Electrical 1!100 Megawatts Unit 3: Thermal 3,250 Megawatts El ectrfcal 1,050 Megawatts METEOROLOGICAL DATA Time:

1100 - 1115 EST Air Temperature:___J!_°F Relative Humidity: 71 Percent

,)

BOAT SURVEY

SUMMARY

WATER TEMPERATURE (THERMOGRAPH)

Daily Mean: Holtwood 3,4 °C (_3.B....1__°F)

Muddy Run 3 o °C ( 31 4 °F)

Mid Survey: Holtwood 3 4 °C ( 3a 1 °F)

Muddy Run 3 J

°C ( 31 6 °F)

WATER TEMPERATURE (SURVEY)

PBAPS:

Discharge 11 q Intake 3 a AT B 9 Pond Surface:

Maximum 11. 9 Minimum 2.9 Pond Bottom:

Maximum 11.9 Minimum 2.8

°C ( 53 A

°C ( 32 4 co ( J 6 0 oc ( 53.4 oc ( 37.2 oc ( ~3.~

oc ( 37.0 OF)

OF)

Fo)

Of)

Of)

OF)

Of)

Station

!l 20.21.58.64 2

2Q Precipitation:

Otf10 Inches (24.our Total)

Location: Boat Station 1

Wind SpE:ed:

12 4 MPH Wind Direction:--"n~or'"""t""'h __ _

Cloud Over: cloudy Conment:

J

• -'.. " :> >;r.::.....

.. *.. rllT!l!~ _j

~

SURFACE JNTAICt:* 57.4 DISCHARGE &5..4 DEPTH 5 FT.

tHrAICE *:. 37.4 0

DISCHARGt:. &3.4

.DEPTH. 10 FT.

JNTAl<E 37.4 DISCHARGE &3.4 PLANT POWER: 197 °/o AVERAGE COOLING WATER 4T; 16.0 *F HORIZONTAL SCALE 40~

~941 ~

FIGURE 6.2 -4 HORIZONTAL ISOTHERMS AND THERMAL PROFILE OF CONOWINGO PONO 0

1000 IOOO 6T AT STATE LINE

• 4. ?I *F (STATE LINE - HOLT WOOD)

DATE 12-26-74 THUR TIME 1100 - ISOO 6-11

i!CW""'**~.-.c*t2Jt1rn~~~... *"':'-......~-- *-*.*.....-::...... --.. *-*-.. r... ~ ~ *

• 1' I,,

\\]

DATE: Tues.

02 11 1975 day month date year TIME:

Survey Start:

1005 Hours (EST)

State Line:

1140 Hours (EST)

Survey Finish: 1440 Hours (EST)

HYDRAULIC DATA Pond Elevation Start:

107.42 Feet Finish:

106.43 Feet Average (24 Hour) Flows:

Natural R i ver_.-3..-2..:., 3"""0._0 _____ CFS Conowingo Inflow 32,000 CFS Conowingo Dam Draft 29,125 CFS PBAPS POWER OUTPUT Unit 2: Thermal 3,280 Megawatts El ecf.ri ca 1 11lQO Megawatts Unit 3: Thermal 3,260 Megawatts Electrical 11080 Megawatts METEOROLOGICAL DATA Time: 1005 - 1020 EST Afr Temperature:___]L'F Relative Humidity: 90 Percent u

BOAT SURVEY

SUMMARY

WATER TEMPERATURE {THERMOGRAPH)

Daily Mean: Holtwood 0.9 oc ( 33.6 OF)

Muddy Run 1.3 oc ( 34.3 OF)

Mid Survey: Holtwood 0.6 oc ( 33.1 OF)

Muddy Run 1.7 oc ( 35.1 OF)

WATER TEMPERATURE (SURVEY}

PBAPS:

Discharge JO.O oc ( 50.0 OF)

Intake 0.7 oc ( 33.3 Of)

AT 9.3 co ( 16.7 FO)

Pond Surface:

Station Maximum l 0. 0 oc ( 50.0 OF) 9 Minimum 0.5 oc ( 32.9 OF) 2,3,4,5,6,7,8 Pond Bottom:

61,68,70 Maximum 10.0 oc 50.0 Of) 9 Minimum 0.4 oc 32.7 OF) 213,6 Precipitation:

0.0 Inches (24 Hour Total)

Wind Speed:

2.8 MPH Location: Boat Station 7 Wind Direction: SSE Cloud Over: Overcast Comnent:

u u

r l

-:_J INTAKE 33.4 DISCHARGE 50.0 INTAKE 33.3 DISCHARGE 50.0 DEPTH 10 FT.

INTAKE 33.r DISCHARGE 50.0 PLANT POWER: 199%

AVERAGE COOLING WATER 4T: 16.7°F HORIZONTAL SCALE

!7 37 I

I 0

1000 4T AT STATE LINE

• 5.0 *F (STATE LINE - HOLTWOOD) 6-13 FIGURE 6.2 -5 HORIZONTAL ISOTHERMS AND THERMAL PROFILE OF CONOWINGO POND DATE 2 -If - 75 TUE TIME 1005 -

I

.J DATE: Wed. March 12 1975 day month date year TIME:

Survey Start:

0915 Hours (EST)

State L1ne:

1045 Hours (EST)

Survey Finish:

1425 Hours (EST)

HYDRAULIC DATA Pond Elevation Start: lDB.02 Feet Finish: 107.82 Feet Average (24 Hour) Flows:

Natural R iver--'3=9..,..""'"00=0.__ ____

CFS Conow1ngo Inflow 38.800 CFS Conowingo Dam Draft 39,950 CFS PBAPS POWER OUTPUT Unit 2: Thermal__,_3""",2=8.... o ___ Megawatts El ectri cal _,lu*...i.:10...,.0'-_-'Megawatts Unit 3: Thermal"""""'3...,,2:..::6;..;:;0 __ -'Megawatts El ectrica l__._1..... 1.... o=o ___ Megawatts METEOROLOGICAL DATA Time:

0915 - 0930 EST Air Temperature:~eF Rel~tive Humidity:J..QlLPercent

\\

J BOAT SURVEY

SUMMARY

WATER TEMPERATURE (THERMOGRAPH)

Daily Mean: Holtwood 3.0 oc (37.4 OF)

Muddy Run oc ( -

OF)

Mid Survey: lloltwood 2.9 oc ( 37.2 OF)

Muddy Run oc ( -

OF)

WATER TEMPERATURE {SURVEY)

PBAPS:

Discharge 12.4

°C ( 54.3 OF)

Intake 2.9 oc ( 37.2 OF)

AT 9.5 co ( 17.1 FO)

Pond Surface:

Station Maximum 12.4 oc ( 54. 3 OF) 9,3-1 Minimum 2.8" oc ( 37.o OF) 3,6,7,8,11,12, 13,19,58,61,62, Pond Bottom:

63,65,68,70,l6A, 3-3,5-4 Maximum 12.4 oc ( 54.3 OF) 9 Minimum 2.8 oc ( 37.o OF) 3,6,7,8, ll, 12, 13, 19,58,61,62,63,65, 68,70,7l,16A,3-3, 54 Precipitation: 0.34 Inches (24 Hour Total)

Wind Speed:

7.2 MPH Location: Boat Station 7 Wind Direction: South Cloud Over:

Overcast Comment:

J

t

~...

t l*

[

f r

~; '.

\\.

f

~

• ~.,

.~

• SURFACE INTAKE 37.2 DISCHARGI 54.3

'-----?17 DEPTH 5 FT.

INTAKE 37.l DISCHAllGE 54. 3 DEPTH 10 FT.

IHTAICE 37.2 DISCHAllGE 54.3 PLANT POWER: 198. 6 %

AVERAGE COOLING WATER aT: 17.1 °F HORIZONTAL SCALE 0 - -

6T AT STATE LINE

• 5.6 *f (STATE LIHE - HOLTWOOO) 6-15 FIGURE 6.2-6 HORIZONTAL ISOTHERMS AND THERMAL PROFILE OF CONOWINGO POND DATE 3-12-75 WED.

TIME 0915 -1425

DATE : Tues.

Aeril 22, 1975 day month date year TIME:

Survey Start:

0820 Hours (EST)

State Line:

1035 Hours (EST)

Survey Finish: 1230 Hours (£ST)

HYDRAULIC DATA Pond Elevation Start:

108.28 Feet Finish:

107.35 Feet Average (24 Hour) Flows:

Natural River 30,300 CFS Conowingo Inflow 30,325 CFS 1'

Conowingo Dam Draft 32,625 CFS PBAPS POWER OUTPUT Unit 2: Thermal 3250 Megawatts Electrical 1100 Megawatts Unit 3: Thermal 3250 Megawatts Electrical 1100 Megawatts METEOROLOGICAL DATA Time:

0820-0BJS EST Air Temperature:~°F Re 1 at i ve Hurni di ty: 64 Percent

\\..)

BOAT SURVEY

SUMMARY

WATER TEMPERATURE (THERMOGRAPH)

Daily Mean: Holtwood 11. 7 oc 53, l Of)

Muddy Run 10.7 oc 51.3 OF)

Mid Survey: Holtwood 11.8 oc 53.2 °F)

Muddy Run 9.9 oc 49,8 Of)

WATER TEMPERATURE (SURVEY}

PBAPS:

Discharge Intake LU Pond Surface:

Maximum Minimum Pond Bottom:

Maximum Minimum Precipitation:

0.0 Inches (24 Hour Total)

Wind Speed:

1.2 MPH Cloud Over:

Clear

\\.)

20.0 oc 68.0 OF) 11.6 oc

52. 9 OF) 8.4 co

15. 1 Fo)

Station 20.0 oc 68.0 OF) 9

11. l oc 52.Q Of) 6,62 20.0 oc 68.0 °f) 9

10. 7 oc 5l.3°f) 6 Location: Boat Station 7 Wind Direction: Variable Corrment::------------:

SURFACE INTAKE 52.9 DISCHARGE 6 B. O 54 COHOWtltGO DAii DEPTH 5 FT.

INTAKE 52.9 DISCHARGE 68.0 60 59

~**,,::::55===~=-------.i(.fr-t.._.i~

DEPTH 10 FT.

INTAKE

!52.9 DISCHARGE 68.0

!16 PLANT POWER: 196. 9 %

AVERAGE COOllNG WATER AT: 1s.1*F HORIZONTAL SCALE I

I I

O JODO

• Oct 4T AT STATE LINE o 3.8 *f (STATE LINE - HOLTWOOO) 6-17 FIGURE 6.2 -7 HORIZONTAL ISOTHERMS AND THERMAL PROFILE OF CONOWINGO POND DATE 4-22-75 TUE TIME 0820 - 1230

DATE: Fri.

May day month 2, 1975 date year TIME:

Survey Start: __ l_D_3_D __

Hours (EST)

State Line:

124D Survey Finish:

1530 HYDRAULIC DATA Pond Elevation Start:

Finish:

Average (24 Hour) Flows:

Hours (EST)

Hours (EST) 107. 73 Feet 106.91 Feet Natural River ____

3_9~,6_o_o ___ CFS Conowi ngo Infl ow __

-'3"'"9_,_,7;...5....;;0 ___ CFS Conowingo Dam Draft 45,625 CFS PBAPS POWER OUTPUT Unit 2: Therma1 __

3_2_00_---'Megawatts El ectri ca 1 __

1_0_60 __

Megawatts Unit 3: Thermal __

3_2_80_-"Megawatts Electrical 1100 Megawatts METEOROLOGICAL DATA Time: 1030-1045 EST Air Temperature:_§_g__°F Relative Humidity:...§.Z_Percent BOAT SURVEY

SUMMARY

WATER TEMPERATURE (THERMOGRAPH)

Daily Mean: Holtwood 12. 1 oc 53.8 OF)

Muddy Run 12.8 oc 55.0 OF)

Mid Survey: Holtwood 12. l oc 53.8 OF)

Muddy Run 12.7 oc 54.9 OF)

WATER TEMPERATURE {SURVEY}

PBAPS:

Discharge 20.3 oc 68.5 OF)

Intake 11.g oc 53.4 OF)

.6. T 8.4 co 15.1 FD)

Pond Surface:

Station Maximum 20.3 oc 68.5 OF) 9 Minimum 11.e oc 53.2 OF) 2 Pond Bottom:

Maximum 20.3 oc 68.5 OF) 9 Minimum 11.8 oc 53.2 OF) 2 Precipitation:

0.32 Inches (24 Hour Total)

Wind Speed:

8 MPH Location: Boat Station 7 Wind Direction: North Cloud Over:

Overcast Conment:

1~

I

. I I.

l

.1 I

i I

I

• I I

{

1

.1 I l

INTAKE 53.4 DISCHARGE 68.5

~

54

__./

68 DEPTH 5 FT.

INTAKE 53.4 DISCHARGE 68.5 54

~

DEPTH 10 FT.

INTAKE 53.4 DISCHARGE 68.5 PLANT POWER: 196.6 %

AVERAGE COOLING WATER n: 1s.1*F HORIZONTAL SCALE I

I I

I O

HOO 4T AT STATE LINE

• 2. 2 *f (STATE LINE - HOLT WOOD) 6-19 FIGURE 6.2 -8 HORIZONTAL ISOTHERMS AND THERMAL PROFILE OF CONOWINGO POND DATE 5-2 -75 FR I.

TIME 1030 -1530

0-1 N

0

)

MOUNT JOHNSON ISLAND 0 UNIT#I r.;;Tl r.;;f1 l.!!..J L!!..J PEACH BOTTOM ATOMIC POWER STATION INTAKE lb. 0 DISCHARGE 84. c;,

.7" ---------**- *-

PLANT POWER: 14'1.3'%

DATE 7-'2*75 DEPTH SUl?f"AC: E 94 CONOWINGO POND I

IOO ZOO 100 4DOPaT KAUii IUT

)

UTM ORIO ANO 1970 MAGNETIC NORTH DECLINATION

~ I

""' I

'*/

I FI<lURF. 6.)-1

MOUNT JOHNSON ISLAND

\\

0 UNIT #1 r.;,;ir.wi L!..!Jl!!J PEACH BOTTOM ATOM!C POWER STATION INTAKE DISCHARGE PLANT POWER:

DATE 7

• 2.*75 DEPTH

~Ul2FACE GONOYllNCO POND 0

.~

10 i;.......sZ:wsa VELOC.IT'T' 0

IOO IOO JOO 400rlU SCALf 11 l(ll UTM GRID AND 111'0 MAGNETIC NORTH DECLINATION I

I I

CJ' I

N N

MOUNT JOHNSON ISLAND 0 UNfT#I r.;;;T! 17.ii!

l.!!JL..!!J PEACH BOTTOM ATOMIC POWER STATION INTAKE 75.b DISCHARGE 84.G PLANT POWER: 149.~%

DATE 7*2*75 DEPTH S'* o CONOWINGO POND I

IOO IOCI 100 400 I llT KAUii mr FI~tlRE 6.J-J UTll GRID AND 1970 llAGNETIC NORTH DECLINATION

C1' I

N

\\..J MOUNT JOHNSON ISLAND

\\

0 UNIT#I r.;;i 17.iil

~l!!J PEACH BOTTOM ATOMIC POWER STATION INTAKE DISCHARG£ PLANT POWER:

OATE:

7-2-75 DEPTH 5 '*O CONDWINGO POND 0

.5 1.0 l;lSps,,..... ~

VELLlC::IT'T' a 100 ioo 1aa *aarcu

~CAL( II ttrr UTM GRID AND 1910 MAGNETIC NORTH DECLINATION I

I I

I I

MOUNT JOHNSON ISLAND

~Nlf#I r;;;;il r.wl l..!!J L..!!.J PEACH BOTTOM ATOMIC POWlR STATION INTAKE 75'. 'Z.

DISCHARGE 84.&

CONOWINGO POND PLANT POWER: 14q.) °lo DATE "7-2-IS DEPTH 10'-o

, )

I IOO 200 JOO 400UIT KAUii HtT UTM GRID AND 1970 MAGNETIC NORTH DECLINATION I

I I

J

C1' I

f\\)

V\\

MOUNT JOHNSON IS LANO

\\

0 UNIT#l r;;;;Tl r.;;;i

~l...!.!..J PEACH BOTTOM ATOMIC POWER STATION INTAKE DISCHARGE PLANT POWER:

DATE 7*2*7'S DEPTH 10'*0 CONO\\'JrnGo POND 0

5 10

~

'1/(1..0<.IT'f 0

100 :00 JOO 400'11' I

st&Lt 1* n:a UTM GRID AHO 1970 MAGNETIC NORTH DECLINATION

0 N

I I

i

' \\

I l

I '

I I

i i

i i

i I

i t

i I I i I

i

' I I

I I

i I

I I L..--'

K r-..._

~

i,....-

LO. -

1--""

/

I i..--

i-L.-"

r-......

L>

0 I

I I/

I

'./

I j

l/

/

J I

I v

Ln 0

I

(:iwn1d :10 1 9Tio1v)

A.l.1?0"13/\\ lNJ21anJ 6-26 0 0

{\\.}

0

()

(1) 0 0

lD 0

0

(\\\\

8 CJ 0 0

\\g 0 0

~

0 0

0 I-w UJ

~

w u

2

~

\\{) -0 r-I f""\\ *

'° r:.:i 0::

0 CJ H

c...

w In \\J

~~

N OJ I

t"" \\J)

J:

w )-

~ ~

~o

~

7.0

7. 1. 0 LIMNOLOGY OF CONOWINGO POND

7. 1. 1 INTRODUCTION Studies of zooplankton and benthic communities began in June 1967.

In 1979 the limnology program was expanded to include detailed studies of the water chemistry and phytoplankton community (as measured by plant pigments).

The location of th~

stations sampled are shown in Figure 7.1-1.

The objectives of the studies are:

(1) to quantitatively and qualitatively monitor the phytoplankton, zooplankton and the benthic communities, and the physicochemistry of the Pond (2) to determine the biomass of zooplankton and benthos (3) to determine the effects of natural phenomena on the phytoplankton, zooplankton, benthos and physicochemistry and (4) to document the effects, if any, of the operation of the Station.

A summary of the limnological findings is given below.

comparisons of the preoperational (June 1967 to December 1973) and postoperational (January to December 1974) conditions are included to support the premise that no "appreciable harm" has occurred.

see SQQQ;!..!1§.

~nd Ma:!;;h:!:!~

J121~2L f?L fil}g 1.21~~L Qt

§ec~ion l~~ for supporting data on water chemistry, Section 2.3 for plant pigments, section 2.4 for zooplankton and Section 2.5 for benthos.

The raw data from which the summary tables are prepared are given in a limnological data report prepared by BQbbin§. _fil!g Math!!f 1ll75cl_.

7.1.2 WATER QUALITY 7.1.2.1 Temperature Monthly mean temperatures between the preoperational and postoperational periods were similar (Table 7.1.2-1).

Thermal stratification (a

decline of 1°c (1.8°F) or more per meter in a thermocline) did not occur in the Pond in either period.

The monthly maximum weekly average water temperatures and minimum weekly average winter water temperatures measured at Holtwood Dam from 1966 through 1974 are given in Tables 7.1.2-2 and 7.1.2-3.

The highest weekly temperatures occurred in July a~d August.

A maximum weekly average temperature of 08.4°F occurred in July 1966.

Maximum weekly average temperatures in the summer usually are in the range of 81 to 86°F.

Minimum weekly average winter temperatures in January and February are less than 33op.

The Pond usually has ice over in January and February depending on the meteorological conditions.

Fo~ the

7. 1-1

~

I :...

' {..

period 1966 through 1974, the period of ice cover usually has been brief, i.e., usually less than four consecutive weeks

• A more detailed discussion of water temperature covering the period of 1936 to 1966, prior to the start of the biological monitoring program is provided in Section 3.2.

~

7.1.2.2 Light Penetration

j.

I l

' i.

' f

• The maximum average light penetration (37-46 inches) in the Pond usually occurs in August through October at a time of relatively low river flow (Table 7.2-1).

Maximum light penetration is usually observed in the lower part of the Pond where depth is 50-90 feet.

Depth of light penetration is lowest in the upper half of the Pond.

Individual measurements have varied from 1 to 140 inches in the period 1967-1974.

7.1.2.3 oxygen No distinct seasonal vertical or horizontal stratification of dissolved oxygen occurred in the Pond in the preoperational or postoperational periods.

Average values given in Table 7.1.2-4 during both periods were lowest in summer (4.1-7.8 ppm) and highest in winter (12.0-15.6 ppm).

compared to the *\\\\

preoperational period, oxygen values for the Pond were lower in

winter, spring and fall and higher in s~nuner in the postoperational period.

These differences are considered natural

~

variations because values at Station 601 (upstream control)

-~

followed the same trend.

oxygen values at Station 605

.(located in the discharge) were similar to those observed for the entire Pond.

7.1.2.4 Biochemical Oxygen Demand Biochemical oxygen demand (5

day BOD) determinations were made by the Baltimore Bureau of Water supply on samples collected at Conowingo Dam in 1960-1967 (Table 7.1.2-5).

Additional data have been collected but these were not available at the time of this writing.

The monthly mean BOD values ranged from 1.5 to 2.1 mg/l with an overall mean of 1.7 mg/l.

No distinct difference in monthly mean values was observed.

The low BOD values indicate that no large amounts of organic wastes were present in the water leaving Conowingo Pond.

No appreciable amounts of untreated municipal or industrial wastes are discharged directly into the Pond other than from upstream sources.

Because of recent stringent state and federal regulations requiring municipalities and industries to treat wastes before discharge into streams, the amount of wastes entering the Pond from upstream should have been reduced after 1967.

For these reasons, the BOD values for Conowingo Pond 7.1-2

since 1967 are probably similar to or less than those reported above.

7.1.2.5 Chemical Parameters Except for the concentrations of the total phosphates and seston (suspended solids)r which are generally higher at the bottom, the values of other parameters are either homogeneously distributed or vary slightly with depth in the Pond (Table 7. 1.2-1).

The monthly mean concentrations of parameters other than nitrates, filterable iron, reactive silica, total phosphates and seston (suspended solids) are generally higher in summer and early fall.

Nitrates (maximum average 8.77 ppm) and fil~erable iron concentrations (maximum average 0.33 ppm) are usually higher in late fall and winter.

Reactive silica concentrations (maximum average 2.69 ppm) are higher in winter and early spring.

From 1971 through 1973 total phosphates (maximum average 0.43 ppm) were higher in late fall through early spring.

In 1974 they were higher in late spring through early summer and late fall (maximum average 0.38 ppm).

The data show that the nutrients (phosphates, nitrates and silicates) are available in the late fall, winter ar.d early spring.

Monthly variation was observed in mean concentrations of most parameters between the preoperational and postoperational periods.

However, the range of variation in the postoperational period was within the range of that observed in the preoperational period (Table 7.1.2-1).

The fluctuations in the l!

concentration of most physicochemical parameters in the Pond coincide with variation in the mean daily river flow.

The concentrations of most decrease as the river flow increases due to dilution.

7.1.2.6 Statistical Analysis The 1971 through _1973 water qualitY-dat~.

we;e an_alyz_ed using a

factorial analysis of variance to detect differences between stations and depths In 1971, Stations 601, 605 and 611; in 1972 Stations

601, 604, 605 and 611; and in 1973r Stations 601, 604, 605, 607 and 611, were tested.

In each year, three

depths, surface 5 ft and bottom were tested.

Data included in the analysis were those available from all stations and depths on a given date.

If some values appeared 11 spurious 11 due to sampling error, two separate analyses were run; one including and the other excluding these values.

We believe that the sampling error was caused by the presence of sediments in the water samples taken at the bottom.

Significant differences (P < 0.05) between stations were noted for phosphates in 1972 when data with "spurious" values were analyzed.

However, when these values were excluded from the 7.1-3

l,

! 1.

r r t*

analyses, significant differences between depths were noted.

The concentrations of seston in 1971 were significantly different (P

~

< 0.05) between stations.

Other parameters did not differ

~.,,/

spatially.

Tukey's w-test indicated that the mean concentration (0.15 ppm) of total phosphates was significantly higher (P

0.05) at Stations 601 and 604 than at Stations 605 and 611 (0.10 ppm).

The mean seston was significantly higher at Station 611 than at other stations.

Only the concentrations of total phosphates in 1972 and 1973 and seston in 1971 and 1972 were significantly different (P

< 0.05) between the three depths.

The concentrations of the other parameters did not differ significantly (P > 0.05) between depths.

The mean values of seston at bottom in 1971 (19.26) and 1972 (27.49) were significantly higher than at other depths.

No significant differences were noted in 1973.

The above analyses indicate that even though some parameters reveal significant differences in spatial and vertical distribution, the differences are not consistent in all years.

Also, the difference between means was small and is hardly of any biological significance.

7.1-4

TABLE 7. l.2-l Ccmpari1oa ot the monthly..,.., value1 of vacer quality parameters 111ta1ured durtag the preoperat1onal (1971*1973) and po1t0per1tlOl\\&l (1974) perf.odl iA Conovtai:o Pand.

Values are eqirused ia mg/1 unleu othenrise specf.fled.

D.lsh indicates pat4metcr 11ot

.. aaund, IUver flDOI data suppt1ed by PennsylvlUl.le li'llwr e114 Light Company &C Kolt'lloc>d Do:a

• f""'l'erature daca taken at llDllitoriag 1tatlona on the day of 1mmpl1.n&,

ttauh Jan rab MAr

~r Kay Jua Jul ADS Sep Oct Nov Dec Par-tar

\\9'7*73 Veter temp. (F)

Surface 34.9 36.5 43.4 49.6 60.3 73.5 79.7 79.8 74.6 u.11 47.9 41.7 llottDlll 3S.O 36.S 43.3 "8.7 59.S 73.6 79.0 711.8 74.5 63.4 49.1 41.5 1974 SaTface 39.0 38.4 42.6 52.7 65.1 73.3 78.9 81.6 71.6 511.7 52 *.5 38.8 llOttOll 38.5 41.11 n.2 63.2 72.0 77.8 79.7 70.3

.57.!I n.6 38.2 Dtuolved Ox71ea 1?67*73 Surface 1.5.5 15.4 13.4 12.11 10.8 1.5 6.4 6 *.2 6.11 8.l 10.2 14.l 10tt11111 1!1.7 1.5.6 13.7 u.o 11.9 '*'

.5.6 5.4 6.S 11.7 11.2 14.4 1974 l1rdace 11.2 12.6 10.8 10.!I l.J 7.1 9.2 9.4 10.0 11.6 Iott Diii 11.4 12.9 11.3 10.Z 7.5 6.!I 6.9 9.l 9.4 9.8 11.6 S.ecbl Dhlt 1967*73

.._diaa (ta.)

32 34 26 27 29 34 42 46 37

%8 1S 1974 u

23 16 28 3J 38 47 39 42 4!I 20 liftr ncrv

!lli:ll

(:s 1000 cf*)

29 *.5 411.3 71.8 75.7

.53.0 49.4 22.7 14.2 11).7 U.11 39.3

.58,9 U74 72.7 47.6 61.4

'2.4 39.7 19.4 Zl,4 10.6 21.2 11.11 23.0

.53.5 Ull:ll.

Surface 7.40 7.10 7.17 7.20 7.39 7.36-7.42 7.60 7,40 7.43 7.33 7.10 lottn 7.16 6.8.5 7.17 7.05 7.40 7.Zl 7.30 7.40 7.33 7.46 7.31 7.iMI 1974 Surface 6,98 6.87 7,0.5 7.05 7.84 7."i2 7.56 7.4.5 7.66 7.7.5 7 *.56 7.26 lottlOlll "

6,92 7.06 6.98 7.66 7.45 7.30 7,.28 7 *.53 7.511 1.,0

).l.5 Cooducttvtty 1971-73 (lllllhoa/i;a at 20C)

Sur!r.ce 100.68 187.21 178.44 1511,20 156.60 1~230.12 2112. 71 312.53 332.57 74.5,16 155.79 loeu.

213.43 120.lB 21S.114 1'6.33 152.81 UZ.50 220.113 279.U 307.64 321.68 233,43 141.45 197' lurfaca 168.50 175.90 147.80 147.80 17~.50 219:'70 178,60 2.54.00 230.01 247.0l 260.49 154.30 lottOll 173.90 146.60 140.30 176.30 220.30 178. 70 251.94 232.49 246.17 255.06 lSZ.37 lic.nonate 1971-73 (BC03)

Surface 36.Bl 34.81 36.22 34.08 35.81 41.95 54,34

.59.15

.59.32

.59.7S Sl.114 32.68 lotto.

37.49 23,86 41.28 33.67 33.73 37.3S 54.21 58.63 4S.36 S7.l4

.51.61 28.90 1974 lurf aca 34.17 211.07 28.17 32.24 40.60 53.76 44.211

.59.04 4!1.26

.53.43 56.2.5 35 *.59 lattOll 32.'9 211.13 29.90 40.80

.54.60 44.76 se.zs 45.4a

.54.07 56.54 34.'2 Caitaoa&t*

1971*73 (CO,)

S11rfr.ca 0,61 o.oo o.oo o.oo o.oo 0.10 o.04 0.01 o.oo o.oo o.oo o.oo lotto.

o.oo o.oo o.oo O.DO o.oo o.oo o.oo o.oo o.oo o.oo o.oo 0.00 1974 lufaca o.oo o.oo o.oo o.oo 0.01 0.00 0.15 o.oo 0.26 0.09 o.oo o.oo Iott ca o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo 0.00

-tlGud 7.1-.5

r TABLE 7.1.2*1

~

Caatl-d.

lloatla Ja fa'b llar Apr Kay

.Jua Jul Aug Sap Oct Hoy Ilea ra~t*r Socll*

ill!:ll (Ila)

Surface 7.90 8.45 6.23 S.72 S.51 S.81 6.U 6.47 9.18 8.53 6.09 s.02 lotto-.

8.32 S.06 6.36 S,61 S.24 S.44 6.44 6 *.56 8.70 8.62 6 *.59 4.21 1974 Sar face 6 *.57 6.43 4.S6 3.S3 4.39 Di

.5.21 1.n 6.70 7.74 8.37 4.80 lottoia 7 *.57 4.66 3.37 4.39 6.99 5.24 7.82 6.75 7.87 8.42 4,85 l'otaHlla 1971*73 (E)

Sar fa.ca 3.30 3.11 2.86 Z.93 2.92 3.47 3.96 4.06 S.73 7 *.54 6.08 3.23 Iott*

2.99 2 *.57 2.aa 2.57 2.18 2.92 3.82 3.90 S.41 6.82 S.36 2.53 1974 Surface 3.15 2.37 2.45

2. ta 2.14 337 3.65 4.38 3.65 3.91 4.36 3.30 t

lottOOI 3.12 2.30 2.18 2.17 3.68 3.70 4.48 3.6) 3.93 4.26 3.26 I

j*

c:alcl*

1971*73 t

(Ca)

Surfaca 25.0 21.6 21.1 11.1 20.3 21.4 29.7 33.3 34.9 3.5.9 30,7 11.3 I I Iott cm 24.8 14.0 24.8 19.1 23.8 23.4 29.0 33.5 34.5 35.3 29.7 19.1

\\'

i ill!

).

Surfae41 21.9 23.3 16.3 17.5 22.1 27.9 22.1 28.5 27.&

29.7 30 *.5 20.1 I

lottoa 21.4 u.a 16.5 22.S 28.S 22.2 27.1 27.7 29./

29.9 20.3

l.

11qn... 1-1971-73

&:a t '

~)

Surface 4.7

.5.3 6.7 s.2 6.2 7.1 11.6 10.1 17.6 a.a 3.2 Bat tom s.z 4.0 1.0 s.3 7.2 S.6

&.o 10.z 10.5 17.4 8.6 2.8 1974 l'

Barf ace 4.6 5.3 4.8 4.6 4.9 6.6 5 *.5 9.8 7.8 8.7 8.3 4.2

~:

Iott*

4.8 4.4 s.o 6 *.5

.5.7 10,6 7.3 9.2 1.3 3.9 t

C211.oriM 1971*73

~

j. r (Cl)

Svrfaca 10.S3 10.71 9.65 7.04 7.11 7.89 11.17 12.41 13.78 16.79 12.38 8.75 Iott...

10.43 6.74 9 *.59 6.42

&.91 7.13 9.96 11.91 U.74 16.26 11.72 7.64 t

~

1974 lvrf a" 8.28 8.40 6.97

.5.90 8.18 u.oz 6, 75 12.37 9.6.5 11.16 11.42 6.93 r

Iott*

8.01 6.79 5.07 8.19 14.93 6.69 12.25 9.52 11 *.56 11.49 6.9:>

Sulfate 1971.73

[ '

(S04)

Svrfae41 44.'4 4%.73 48.9S 36.18 37.24 47.60 58.93 73.19 9Z,04

'1.43 75 *.53 37.42 lottoa 4.5.40 2a.a8 59.17 41.17 37.61 43.37 58.39 72.4S 92.28 93.13 67.42 33.74

~

ill!

i* r *

-Surface_ 41.22. 44.89 - 36.1,2 35.24 42.23 - 50,11_ 40,87 67.25 61.36 70.07 --

64.94 38.04 lottCllll 43.JS 35.31 32.93 40.35 50.75 38.60 62.26 59.94 70.11 60.lta -

37.17

~

• ltrlC.

1971.73 I" '

,1 (11>2)

Surface 0.0.5 0.13 o.os 0.04 0.04 o.os 0.07 0.12 0.14 0.10 0.06 o.os ir, lottoa 0.06 0.20 0.06 0,04 0.03 0.07 0.12 0.14 0.14 0.12 0.06 0.05

~-

1974

~:*

Sar face 0,04 O.Olt 0.03 0.04 O.OJ 0,05 0,06 0.14 0.07 0.05 O.OJ 0.03 Iott*

0.03 0.03 0.04 0.03 0.05 0,07 0.16 0.01 o.04 0.02 0.03

• • }*

• le rate un-n (N03)

Surface 7.14 8.17 6,2, s.,a S.49 5,oa

.5.61 S.31 7.13 1.60 6.S4 S.42 lotU.

1.92 4.117 4.7S 4.71

,,10 4.70

.5,64 4.12 6.67 7.59 6.23 4.14

~

1974 larf*c*

7.89 S.56 S.48 4.41 3,50 i:9i 1.68 2,08 2.611 2.44 2.sa J,14 lottoa 1.77 s.u 4,39 3,30 l,90 1.69 2.lt 2.'9 2.ss 2,32 3.19 t

l' oo.tiauad

~

"t 7.1-6

I;,.

~,

TASL'E 7.1.2-1 I

Coatlo.,.d.

I_

Kalltb Ju Feb Kar Aflr Ka7 JUD Jill Aug Sep Oct Nov

'Dec rarametH' filterable lroo 1971-73 (Fa)

Sllrfac*

0,30 0.06 0,13 0,11 0,06 lf.Ci']"' 0.03 0.02 O.G4 0.12 0.09 0.12 lot tom 0.08 0.01 o.u 0.10 o.os a.oz 0.02 0.02 0,04 0.11 0.09 0.18 1974 Sur tac*

0,20 0.03 0.01 0.02 O.Ol 0.02 0.02 0.02 0.02 0.03 0.05 0.18 Bott-O,ll 0.01>

0.03 0.04 0.01 0.02 o.o~

O.Ol 0.02 o.os D.ll SlUc:a 1971*73 (S10rS1)

Sur fee*

1.12 1.46 1.23 0.79 1.20 o:67 0.84 0.114 0.66 0.41 0,84 0.94 toCCOCD l.2S 2.44 l.6S 1.05 1.20 o.as 1.01 0.90 0.76 0,50 1.0S 1.24 1974 Slarfac*

2.69 1.40 2.11 2.10 0,82 0:34 1.17 0.82 1.31 0.28

o. 70 1.99 Bottom 2.68 2.11 2,14 o.~2 0.3' 1.19 0.85 1.l4

0. 10 0.15 1.98 Pho1phata 1971-73

{1'04)

Surt.ca 0.14 0,26 0.16 0.15 0.14 o:u-0.11 0.11 0.10 o.c9 0.21 o.u llottoaa 0.16 0.43 0.12 0.17 0.16 0.15 0.19 O.ll 0.16 0,14 0.16 0.25 1974 Sllrface O.ll 0.11 0.10 0.20 0.23 o-:22 0.24 D.16 0.20 0,18 0.16 D.2S Bott....

0.14 0.11

0. 27 0.38 O.J8 o.:n 0.20 0.24 0.26 0.20 0.25

Sutoo (Su*pended 1971-73 Solld1)

Slldaca 16.8 96.8 23.2 18.0 19.4 ~

23.8 12.8 14.Z U.l 28.6 43.l Bottom 6.l 216.6 28.1 15 *.5 25.6 38.4 45,7 27.l 20,l 17.4 28.l 44.J 1974 Surlaca 21.9 13.4 8.7 28.8 18.4 1IT' 11.4 7.4 U,8 10.J 1.a 17.3 Jottoa 37.3 21,9 45,5

44. l 70.7 17.0 13.1 16.7 25.5 14.4 20.8 7.1-7

T A:!LE 7. l. 2-2 lfax1Dum veekly average vater temperature* (F) measure.cl at Holtvood Dam, January*

DecClllber, 1966-1974.

tear Jan Feb Mu Apr Ha7 Juo Jul

.Aug Sep Oct llav Dec I

1966 37.1 37.4 48.1 S5.7 69.0 86.0 88.4 85.4 84 *.5 64.8 56.7 40.2

r.

1967 36.0 33.5 44.9 57.2 6.5.5 80.9 83.1 80.2 7.5.5 65.2 47.0 39.6 1968 32.5 32.6 54.0 62.6 62.9 7S.7 85.9 85.1 64.8 55.1 42.4

~

1969 32.3 32.5 44,6 58.4 69.7 83.3 82.5 80.3 77.7 66.1 51.8 35.4 i *

~.

1970 32.2 33.3 41.3 58.6 71.5 77.0 83.6 85.1 80.6 68.9 53.2 37,6

~.

1971 32.5 37.3 43.6 54.6 64.0 84.7 85.3 82.2 82.7 72.0 46.6 42.0

• (

1972 36.7 37.1 41.0 58.6 71.0 71.5 83.6 81.1 79.0 64.0 53.0 39.4

f.

1973 40.0 37.3 48.4 61.4 60.1 79.S 81.7 82.7 83.3 67.8 49.0 4S.1

~*

1974 39.9 37.7 43.6 63.0 71.2 79.:S 83.5 85.4 77.8 63.7 61.9 38.3 t*

~

g.

• Temporature oat avat.lsble

~

~

f Lr I!

TABLE 7.1.2-3 i'.

~*

Miui11&1111 veekly average vintervater tamperature (P) (December*

r March), measured at Holtvood Dam, 1966-1974.

r

~-**

Month r.:

~'.

\\i.

Tear J'an Feb Kar Dec i;.

f:*..,

1966 32.2 32.2 38.4 32.4

~* I 1967 32.5 32.4 34.11 35.2 1968 32.2 32.3 33.1 32.1

~'

1969 32.l 32.2 32.9 32.1 1970 32.1 32.3 35.6 33.5 t~..

~

1971 32.3 32.6 37.3 37.6 t"*

1972 32.B 32.4 35.8 34.4 i~:

1973 32.9 32,6 43.l 33.9

\\

41.7 f'

1974 32.5 32.8 r

t!.,

7.1-8

• • r TABLE 7.1.2-4 Comp&'l'i*"" af the **atonal vertical di*t'l'ibutlan of dlatolvad o><ygen (ppt11) duTing the preopeTatlon&l (1967-1971) and pottaperatlan.ol (1974) p*rlod* for Canov{nr.o Pond (all scacion1), Statton 601 (located upstreL.,. frOlll Peach llottOlll Atoadc Power St.acton), Sta.tl~n 605 (loca.ccd in tho dtecharge frr>m Puch loccan1 Atomic Powr Statton) and Station 611 (located dov:istream f.,,m Peoch llo:ltCC'1 At""'1c Fa""r Statton n*&T Conowingo Oa111),

Vtater Sprtag SIDDllr rall Seuon (Ju*"t'..ar)

(Apr-Jun)

(Jul-Sep)

(Oct-Dec)

Pe'l'iod 1967-1973 1974 1967-1973 1974 1967-1973 1974 1967-1973 1974 Deptb Coa.avi"IO Pond 0

14.6 11.2 10.2 9.9 6.5 7.4 10.9 10.3 (all nattoaa) s 14.a ll.9 10.8 9.9 6,6 7.6 11.l 10.3 10 14.9 12.6 10.9 9.8 6.6 7.2 11.6 10.3

• 1s

u. 2 12.8 10.5 9.7 6.4 6.8

11. 7 10.6 Station 601 0

14.6 13.1 9.6 9.5 5.7 6.J 10.1 10.l (upatnu

.s 14.9 13.5 10.4 9.5 5.7 6 *.S 11.Z 10.l COlltral) 10 14.8 10.1 9.4

.S.4 6.3 11.7 10.6

• l.S 15.3 12.7 10.1 9,9 6.1 6 *.S 13.0 10.1 Stactan 605 0

14.8 U.4 9.8 10.0 6.7 7.S 11.1 9.9 (dlacharge)

.s u.o U.4 10.1 10.0 6.11 7,g 11.1 10.0 10 u.o 12.3 10.2 10.0 6.4 7 *.S 11.2 10.\\

• 1s u.o 12.0 9.6 10.2 5.7 7.4 10.6 10.3 Station 611 0

1.5.1 12.8 9.8 10.5 6.7 1.1 10.6 10.0 (dovaatrum) 5 15.2 12.7 10.1 10.5 6.6 1.1 10.7 10.0 10 lS.2 12.8 10.0 10.4

'~

&.a 10.7 10.0 lS 15.J ll.4 10,Z 10.4 6.S 6.6 to.a 10.6 20 U.4 13.4 10.2 10.0 6.7 6.6 10.9 10.6 30 15 *.S ll.5

\\0.4 9.8 6.5 6.4 11.1 10.7 40 15.6 13.6 10.S 9.9 6.4 6.2 11.4

i.O *.S so lS.3 13.8 10.4 9.4 6.0 11.4 10.9 60 15.3 13.6 10.6

11. l l.l

.s.1 11.l 10.Z

• 65 u.1 13.2 10.0 9.1 4.l 4,9 11.1 9.4

• }lean kttOOI depth 7.1-9

i I

I ;-r'

~ f r t*

t.

~

TA'3LE 7.1.2-5 Mol1thly oean, minimum and maximum biological oxygen demand CS-day B.O.D.) value1 (mg/l) from sample1 collected at Canovi1110 Dam by the Baltimore Bureau of Water Supply, 1960-1967, Data 1upplied by the STORE? System of the Environmental Protection Agency.

N repreaenta the number of determi11actona m&de, Hauth

.Jan Feb Kar May Jun

.Jul Aug Sep Oct

!lov Dec:

Grand Valuea II 21 20 24

z:z 22 2S 30 27 21 2l 27 16 278 Kean 1.S 2.0 2.1 1.6 1.6 1.9 1.6 1.9 1.s 1 *.5 1.8 1.6 1.7 Min 0.4 0.5 0.7 0.6 0.6 0.1 o.o o.o o.o 0 *.5 o.a 0.8 o.o Hu 3.2 3.3 4.1 2.a 3.0 4.1 3.3 4.4 3 *.5 2.9 3.6 2.6 4.4 7.1-10

{ :

MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE PONO FISHING CREEK MUDDY CREEK 0

I PEACH BOTTOM

~.

ATOMIC POWER **<'\\

STATION STONEWALL POINT STATE LlNE-P_A_. -----

MO.

I 2

S I

I I

SCALE IN MILES PEACH BOTTOM BEACH WILLIAMS TUNNEL GLEN COVE FIGURE 7.1-1 Distribution of l!mnolosical stations in Conowlnso Pond.

7.1-11

i *

7. 1. 3 PHYTOPLANKTON COMMUNITY 7.1.3.1 Species composition Populations of algal cells retained by a

1. 20 mesh plankton net in June through October were enumerated and identified to genera in 1967 through 1969.

A list of genera of algae collected in the Pond is given in Table 7.1.3-1.

Common genera collected were

~~n92fin~,

f1eog2rin2.

~§9i2§££Bm,

~elQ§i£2* ~§teri2n~1!2, An~£ysti§, gQmQhQ§Eh~~ri~ and 8n~bafill~*

The abundance of groups of algae differed monthly; green algae were common in August and September, brown algae in October, diatoms in June and July and blue-green algae in September and October (Table

7. 1.3-2).

Overall, diatoms were dominant and constituted 49% of the algal population.

Although blue-green algae were common in September and October, they were not the dominant group in the Pond.

7.1.3.2 Plant Pigments The concentrations of chlorophyll~ (total and active),

Q,

£,

phaeo-pigments and carotenoids have been measured at selected monitoring stations since 1971 to indicate the standing crop of algae in the Pond.

Comparison of the monthly mean pigment concentrations in the preoperational (1971-1973) and postoperational (1974) periods is given in Table 7.1.3-3.

N~

substantial differences were noted.

No distinct vertical stratification of any plant pigment occurs in the Pond (Table

7. 1. 3-*3)

• Most plant pigment concentrations are low in late fall through early spring, increase in mid and late spring and peak in summer and early fall.

Variation in monthly mean concentrations occurred between the preoperational and postoperational periods.

However, the range of variation between periods was similar.

concentrations of total chlorophyll ~ at Stations 601 (upstream control). 605 (discharge),

and 611 (downstream from discharge) on each sampling date in 1971 through 1974 are shown in Figures 7.1.3-1 to 7.1.3-4.

The overall Pond averages are also shown for comparison.

The pattern of chlorophyll a

distribution at the selected stations is similar to that in the entire Pond.

The peaks occur at the same time at all stations.

However, the occurrence of these peaks within seasons can vary between years.

The general pattern is one of small peaks in late spring and fall and a

maximal peak in the summer.

The concentrations are lower in November through May.

There is little evidence of spatial differences in chlorophyll concentrations.

The postoperational values at Station 605 are 7.1-13

within the range of variation observed in the preoperational period.

The relationship between concentration of chlorophyll

~

(total}.

nitrates, phosphates in 1971-1974 is shown in Figure 7.1.3-5.

Data for this figure are given along with water temperature, river flow and zooplankton density in Table 7.1.3-4.

The concentrations of nitrates and phosphates are usually higher in the fall and winter months while the chlorophyll s

concentrations are generally low in late November through early April.

However, the fluctuations in the concentration of phosphates are less than those for the nitrates.

The values for phosphates ranged from 0.08 to 0.36 ppm but for the nitrates the range was 0.83 to 15.19 ppm.

It is important to note that the nutrients and phytoplankton are present throughout the year and are never completely depleted.

7.1.3.3 Statistical Analysis The relationship between the concentration of total chlorophyll

~ and the water temperature, average daily river flow, nitrates, phosphates, reactive silica and depth of light penetration (Secchi disk measurements} was examined by stepwise multiple regression analysis.

The data collected in 1973 were used for this analysis.

The six independent variables accounted for 66.63 of the total variation in chlorophyll~ concentrations (Table 7.1.3-5).

The water temperature alone accounted for 60.8% of the variation.

The depth of light penetration, reactive silica and* phosphates accounted for an additional 5.2% of the variation.

Examination of the simple correlations and signs of the regression coefficients indicated that the water temperature is positively related while the nutrient elements and the river flow are negatively related to the total chlorophyll ~*

That is, as the water temperature increases chlorophyll s increases and as river flow increases the chlorophyll

~ values decrease.

An increase in nutrients coincides with a

decrease in the phytoplankton.

The water temperature had the highest correlation (r = 0.779) with chlorophyll s*

The standardized partial regression coefficients revealed that the water temperature is about four times more important than the depth of light penetration or concentration of phosphates in predicting the concentrations of chlorophyll g.

The reason that the water temperature is more important in the Pond than the nutrients is because the nutrient levels do not fluctuate widely and they are generally available throughout the year.

7.1-14

I

~. \\' * ".'

7.1.3.4 Aquatic Vascular Plants Macrophytic aquatic plants are not common in the Pond A list of species observed is given in Table 7.2.3-6.

A few macrophytes occur from Holtwood Dam along the shallow rocky areas of the west shore to a point approximately one mile below the Darn (Figure 7.1.3-6).

The common species is the water willow

(~~~~ic!~

~.m.g~i.£.2D2)*

Small isolated beds of macrophytes are found in Hopkins cove and at the mouth of tributary streams such as Peters Creek and Wissler Run.

A small bed of water willow, located at Burkins Run, is the only bed of aquatic macrophytes which is impacted by the thermal plume.

No deleterious effects have been observed since PBAPS began operation in January 1974.

7.1-15

TABLE 7.1.3-1 A list of genera of algae collected in Conowingo Pond, 1967-1969.

Green Algae Chlamydomonas Eudorina Pandorina Pleodorina Volvox Haematococcus Sphaerocystis Golenkinia Micractinium Errerella Dictyosphaerium Coelastrum Hydrodictyon Pediastrum Oocystis Ankistrodesmus Clostedopsis Kirchneriella Selenastrum Actinastrum Scenedesmus Closterium Cosmarium Staurastrum Spirogyra Yellow-green Algae Gloeobotrys Yellow-brown Algae Mallomonas Synura Dinobryon 7.1-17 Diatoms Melosira Stephanodiscus Asterionella Fragilaria Gyro sigma Navicula Nitzschia Brown Algae Ceratium Peridinium Blue-green Algae

.Anacystis Coccoch 101. ls Gomphosphaeria Anabaena Aphanizomenon Nos toe Rivularia Oscillatoria Spirulina

r I

f :*

~

i ".

~ '

r

~

t*. f f;'

~

!~ t.

!(

i*

~ t [*

j, f:

l

~ t

~ ;,...

~

~~-

1*

~ **

~.

TABLE 7.1.3-2 Monthly variation in the percentage composition of the major groups of algae in Conowingo Pvnd, 1967-1969.

Group of Algae Jun Jul Aug Sep Oct Average Green 16.3 21.3 40.5 31.4 5.0 27.4 Yellow-brown o.o 0.6 0.6 0.4 o.o 0.6 Brown 0.1 1.2 1.5 1.6 15.0 5.1 Diatoms 75.0 63.8 31.4 31.6 46.0 49.0 Blue-green 4.0 9.5 17.8 30.0 32.0 19.7 7.1-18

I, j

'!'~!\\!.~: 7.1.)-3

~ :

C:Olr.p.iri.;on 1>f the ci1>nthly mc.tn plunt PiGl'l"nt concentrations (!0i:/i0l) during the prcopcr.:itional (1971-197)) and postopcr.:iti1>n~l (1974) purl.ods in C1>nowin&o Pond, Da&h l.ndl.c.:it<>:; plg.:.:nt n1>t mcilsurcd.

I!

~:on th J11n Feb MaT

.\\pr May Juo Jul Aug Sep Oct Nov Dec

'.t Chlorophyll !!. (Total) 1971-1973 Surface l.56 0.88 2.18 5.22 17.29 25.91 16.01 21.59 17.64 16.84 13.)7

).60 8otlom 0.62 1.75 l.89 3.51 14.51 22.88 16.10 16.36 15.1+8 13.93 10.66 4.47 1974 Surface 1.64 1.57 l.46

4. 73 33.22 28:4'°3-

23. 54 ts.OIJ 28.83 23.18

14. 74 4.36 Butt om l.41 2.20 Z.86 35.6) 27.18 24.44 lZ.40 27.31 24.93 11,50 4,84 Chlorophyll.!!. (1\\ctiva) 1971-1973 Surface l.58 0.80 Z.38 2.46 11.41 15.61 10.08 13.05 9.10 9.Jl 8.38 2.49 Bottom 0.60 0.80 0.56 2.58 10.87 11 ** 71 10.63 9.33 9.97 9,61 6.3Z 2.40 1974 Surface l.11 0.40 0.85 2.90 27.05 2o:U-17.05 10.60 19.S5 15.22 11.62

l. 71 Bottom 1.12 0.88

l. 76 27.15 16, 10 14.42 8.45

17. 78 15.78 7,21 l.20 Chlorophyll 2 1971-197)

Surface 0.23 0.43 0.39 0.89 0.74 1.02 l.42

?. 7l 9.10 2.27 l.55 l.01

f Oottoe1 0,28

o. 79 1.08

l. 28

0. 74 l, t; 2,06 3.29 4.35 3.30 1.82

l. 75 1974 Surface

1. 7l 2.53 0,34 0.90 1.32 2:-15 2.02 2.04

3. 35 2.05 l.34 2.96 8otton1 1.35 l.09 1.28 0.93 3.40 2.43 2.01 J,19

l. 2.9 1.56

2. 72 Ch lorophy 11 5.

1971-1973 Surface l.19 l.Jl 1.09 1.63 5.68 4.19 3.62 5.S4 4.80 4.65 4,44 2.57 tot tom

o. 76 2.46 2.98 1.44 S.77

5. 7J 5,25

4. 33 4.30 5.95 3.86 3.511 llli.

Surface 3.60 5.81 IJ.85 3.16 14.26 9,23

7. 36 8.21 11.42

7. 30 6.62.

7.85 Bottom 2.70

3. 61 3.60 13.98 14.10 6.41 4.57 8.34 S.97 6.04 6.68 Phneopigments 1971-l9il Surface 0,39 0,37 l,05 4.11 7.56 14.29 8.36 12.14

11. 70 10.02 5.67 2.32 Bottom 0,56 l.44 Z.5' 2.15 S.75 13.62 9.08 11.68 10.37 6.94 8.09 3.91 1974 Surface l.19 2.21 1.05 3.12 9.33 13"30

10. 27 7.30 14.67 12.94 4,96 4.77 Bottom 0.64 2.59 l,94 13.01 18.33 16.16 6.43 i,.sa

14. 1e 7.09 5.81 Carateaold1

(~ltn.)

1971-1973 Su-rface 0.36 0.45 0.57 l.01 5.03 7,03 4, 76 S.49 4.50 4.06 3.86 1.38 Boe tom 0.23 0.12

o. 35 0.76 4.44 6,20 5.42 5.ZZ 4.48 4.85 3,49

l. 66 1974 Surface 0.14 0.38 0.01 l.09 10,86 8:73 7.47 3,53 7.25 6.15 4.33 0.08 Bottom o.oo 0,36 0.58 11.30 8,27 8.03

~.31 8.28 7.49 3.72 0.28 Carotcnoids (~~~.)

1971-1973 Surface 0.91 1.14 1.41 2.53 11.58 17.34 11.89

13. 72 11.24 10.16 9.66 3.45 Bottcm 0.58 0.30 0.87 1.90 11.10 15.49 13.56 13.04

11. 20 12,lZ 8,72 4,16 1974 Surf ace 0.35 0.95 0.02 2.72 27.16 21:83 18.66 8.82 18.13 15.36 11.31 0.19 Bottom 0.00 0.90 l.44 28.26 20.67

!0.07 8.27 20.10

18. 72 9,JO 0.69 7.1-19

7.1-20

• i:

TA~LE 7.1. 3-5

~ : * *

• t :

'; ** : '-1

• ~ '

ll.egresaion statistics for the concentration of total chlorophyll ! (mg/m.3) and physicochemiul -.. '

• parameters in Conovingo Pond, 1973.

, 1:*.

Order of entry of Variables

• r.x Vater Temperature (F) 0.608 0.296 Secchi disk (inches) 0,622 0.292 Phosphates (ppm) o.644 0.285 Reactive ailica (ppm) 0.664 0,279 lliver Flow (100 x cfs) 0.66.5 0.279 Nitrates (ppm) 0,666 0.281 r98df, 0,05

• 0.197 I'

• 0,253 98df, 0.01 7.1-21 Simple Correlation 0.779**

0,118 NS

-0,118 NS

-0.299 **

-0.493**

-0.298**

,:."';~:.:~v*.:.

Standarize~ ;:*.*, ;

• Partial R.eg'rea- **

• don Coefficiel:it '

'1't..'

-0.044 : \\**~:':...

• , l** * *

• t '

'I ~ *... *,

r I

' ; r TABLE 7.1.3-6 List of macrophytic aquatic plants found in Conowingo Pond.

Species SWamp milkweed - Asclepias incarnata Bur marigold - Bidens sp.

Turtlehead - Chelone glabra Sedge - Cyperus strigosus Three-way sedge - Dulichium arundinaceum Spike rush - Eleocharis acicularis Spike rush - Eleocharis spp.

Joe-Pye weed - Eupatorium dubium Boneset - Eupatorium perfoliatum Halberd leaved rose - Hibiscus militaris Blue flag - Iris versicolor Rush - Juncu'SS'Cuminatus Soft rush - Juncus effusus Water willow - Justicia mericanan Cardinal flower - Lobelia cardenalis Great lobelia - Lobelia siphilitica Seedbox - Ludwigia alternifolia Yellow loosetrife - Lysimachia terrestris Spiked loosetrife - Lythrum salicara Monkey flower - Mimulus ringens Yellow pond lily - Nuphar advena False dragonhead - Physostegia virginiana Smartweed - Polygonum densiflorum Pickerelweed - Pontedaria cordata Broad leaved arrowhead - Sagittaria latifolia Engelmanns arrowhead - Sagittaria engelmanniana SWordgrass - Scirpus americanus Soft stem bulrush - Scirpus validus Bur reed - Sparganium sp.

Slough grass - Spartina pectinata Common cattail - ~

latifolia Water celery - Vallisneria americana 7.1-22

-1 i.

,r

• llSI

.-1........

.-IC"'I

£ a

p. -

0 f!l

~ '-'

.c u

.-1

.-1

>. c"'i'

-§. a o-H

~

.3 '-'

tj all

..-I

.-1 Ei;

p. -

~ ~

.-1 '-'

t3

..-I

>.C"la

.c -

e-r 0 '-'

6 30 Conowingo Pond 20

__ Surface

... Bottom 10 0

30 Station 601 20 -- Surface

... Bottom 10 0

40 Station 605 Surface 30

• • • Bottom 20 10 0

30 Station 611

-- Surface 20

• ** Bottom 10 0

JAN FEB MAR APR MA'l JUN JUL AUG

~EP OCT NOV DEC FIGURE 7.1.3-1 3

Average chlorophyll ~ (mg/m ) r.oncentrations in Conowingo Pond and at Station 601 (control), 605 (discharge) and 611 (downstream) in 1971.

7.1-23

I r;..

I t

1111

~

~MS

.c......

g-

~

~

0

~

6

!di

~

~

.c ("\\a

p.......

~ ~

~

.c u

a1 I

~

~

~

p.

o ("\\a

~......

~ ~

u 30 20 10 0

40 30 20 10 0

40 30 20 10 0

Conowingo Pond

-- Surface

• • • Bottom

~

Station 601

__ Surface

• • • Bottom Station 605 Surf ace

• • • Bottom Station 611

__ Surface

• • • Bottom JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC FIGURE 7.1.3-2 Average chlorophyll a (mg/m3) concentrations in Conowingo Pond and at Station 601 (control), 605 (discharge) and 611 (downstream) in 1972

• 7.1-24

.Allllit.

.J

all

~

~

E'

0.

0

~

0 M

6 all M

M E'

0. e 0

M 6

1111 M

M E' g.

~

0 M

6

<<II M

M >.

.c:

0.

0 0

M.c:

u 30

~ 20 -: - 10 0

50 40 cwf' a 30 -

2P - 20 10 0

40 30 -

('I')

~ 20

~ - 10 0

30 -

C"')a 20 -

~ 10 0

Conowingo Pond

_Surface

• • • Bottom Station 601

_Surface

• • • Bottom Station 605 Surface

• • • Bottom Station 611

_Surface

• • • Bottom JAN FEB HAR APR MAY JUN JUL AUG SEP OCT NOV DEC FIGURE 7.1.3-3 Average chlorophyll.!. (mg/m3) concentrations in Conowingo Pond and at Station 601 (control), 605 (discharge) and 611 (downstream) in 1973.

7.1-21'

1

• 1111......

~ Mii c:a.

e l 0... a 40 30 20 10 0

so 40 so Conowingo Pond

__ Surface

• ** Bottom Station 601

_Surface

• • • :Bottom Station 605

_Surface 40

• • • Bottom 10 60 so

......,,r-t J! 40 e r 0

6 30 20 10 Station 611

_Surface

• • • Bottom i i

! j 1

.... 1 JAN FEB MM APR MAY JUN JUL AUG TABLE 7.1.3-4 Average chlorophyll ! (mg/m3) concentrations in Conowingo Pond and at Station 601 (control), 605 (discharge) and 611 (downstream) in 1974.

7.1-26

~..,.

40 30 20 10 0

40 30 20 10 0

J 1971

-1

___ P04 x 10 (mg/l)

- NO (mg/l)

J

• Ch~orophyll !. (fllf,/m )

1973 r

J J

A S

Pinl.lRE 7, 1, 3-5 1972 1974 0

N KJJASONI>

Plot af total chlorophyll ~ (mg/m3), nitrates and phosphate* (ppm) in COnovingo Pond, 1971-1974.

7.1-27 16 u

8 4

}

0 I~

I(

2""

12 8

4 0

~* c !

i I

L l "

I

~ *.

l I !.

l 1.-

l:

MUDDY RUN RECREATION L,AKE MUDDY RUN PUMPED STORAGE PONO MUDDY CREEK PEACH BOTTOM ATOMIC POWER STATION STONEWALL POINT STATE LINE-P_A_. -----

MO.

0 I

2 3

I I

I I

SCALE IN MILES PEACH BOTTOM BEACH WILLIAMS TUNNEL GLEN COVE

\\

FIGURE 7.1.3-6 Map of Conowingo Pond showing distribution of aquatic macrophytes.

7.1-28

I

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-:1

• \\

• ' l,,

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r*

r*,.

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~-

7. 1. 4 ZOOPLANKTON COMMUNITY 7.1.4.1 Species composition I

The crustjacean zooplankton community of the Pond is '-'

comprised of 53 species (Table 7.1.4-1).

Six taxa have dominated the community from 1967 through 1974 (Table 7. 1.4-2).

In order of decreasing abundance the common taxa are:

nauplii, cyclopoid copepodids, g~phn!~ sp.,

Bo£m!n~

lQ!lg!fQ§~fi§,

Qi~EhanQ§QID~

lg~£h~gnbefg!2n~~, and QY£1Q22 Y~£n~li§.

The abundance of these taxa has varied between stations, months and years.

No [(

differences were noted in abundance of these taxa between the preoperational and postoperational periods (Table 7.1.4-3)

• 7.1.4.2 Abundance Total zooplankton densities are low (average less than 3 animals per liter) from November through May (Table 7.1.4-4).

From June through October, the monthly average density may exceed 100 animals per liter.

Generally, two* peaks of abundance occur, usually in July or August and again in September (Table 7.1.4-5 and Figure 7.1.4-1).

Peaks occur at times of high temperature (July and August) and low river flow (< 25,000 cfs).

The density of zooplankton decreases sharply when the water

~emperature is below 60 F.

Production increases sharply in the spring when the water temperature exceeds 60 F.

It should be noted that a rather abrupt decrease in zooplankton production coincided with the flooding associated with Tropical Storm Agnes in June 1972 (Figure 7.1.4-1).

Record high flows were recorded in the June 1972 flood.

The Pond was flushed rapidly and water temperature was depressed for thre~

weeks following the storm.

The temperature decreased from 75 F on 21 June to 58 F on 25 June.

It reached 75 F again on 14 July.

Zooplankton production did not recover until August; consequently, zooplankton densities for 1972 never reached the peaks observed in other years.

Cowell (1967) reported that water exchange rate in a reservoir or stream like system must b~

greater th~n 18 days to permit significant development of zooplankton.

The production is considerably greater when flushing time is more than 15 days.

7.1.4.3 Statistical Analysis In order to detect the effects, if any, of the operation of PBAPS on the zooplankton community in the

Pond, a

simple regression model was developed to isolate the thermal effects

~hat may be localized or widespread, from those due to natural causes.

The technique is based on the hypothesis that if ambient Pond conditions change due to natural causes than locations 7.1-29

i.

I t'.

t i

~

within and outside the thermal plume should be similarly affected.

The model provides a

quick method of "flagging" values, with a given level of confidence, that are beyond the range of natural variations in the postoperational period

• It is assumed that (1) some unique relationship (predictive) exists between the density of zooplankton at a control station (Station 601) and the other 10 stations (Stations 602-611).

That is, if the density of zooplankton, water temperature, and flow conditions are known at the con~rol

station, the densities at other stations can be predicted within specified variation (90%

confidence interval in this case).

These predicted densities should agree well with the observed values within the specified variation unless significant changes have occurred in the zooplankton community.

In which case, the values may fall outside the confidence limits set on the relationship between the observed and the predicted values.

However, one would expect up to 10~ of the values to fall outside the confidence limits on a random chance alone.

The data from 1967-1971 and 1973 were analyzed by a

stepwise multiple regression technique for a model run.

The following generalized model was used for each station, Y

= a + b x

+ b x + b x

+ b x i

1 j

2k 31 4m where Y =log of density at a Station i, i = 602, 603, ***, 611 i

x = log of density at Station 601 (control) j x

= average daily water temperature for past days k

j = 1. 2,..., 15 x = average daily river flow for the past 1 days 1

1 = 1, 2,..., 15 x

= total degree days for past m days m

m = 1

• 2,..., 15 A total of 46 independent variables was available for regression analysis for each of the 10 dependent variables (Stations 602-611).

The water temperature and daily river flow data were obtained from Holtwood Dam and were provided by the Pennsylvania Power and Light Company.

All calculations were performed using the Statistical Analysis System (SAS) package

7. 1-30

r I l l j f~* n '.

~ ;

[i f I I !

' l

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I';

I'

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1 \\

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. 1 1.1 i I f.;

, I

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(August 1972) and supplementary procedures, edited by A. J. Barr, and J. H. Goodnight, Department of Statistics, North Carolina State University, Raleigh, N.c.

These calculations and all the equations are given in Purdy, et. al, (1975a, b, c, d).

The computer program selected the best combination of variables from the 45 available.

Each of the resulting equations explained a

large proportion of the variance (R2) and had the smallest standard error (sy.x}.

The density data were substituted in the equations and densities estimated for each station.

These estimated densities were plotted against the observed values and a

regression equation was obtained.

The agreement was good between the observed and the predicted densities.

The 90% confidence intervals were obtained around the points on this regression line.

If a significant number of observed densities deviate from the predicted in any year they should fall outside the confidence limits and thus be readily detectable.

The data from 1972 were used to verify the applicability of the above regression technique.

The year 1972 was chosen for verification because a natural catastrophe due to Tropical Storm Agnes had occurred.

The densities at Station 602-611 in 1972 were predicted from the densities, water temperature and flow conditions at station 601 using the above equations.

A good agreement was noted between the observed and estimated values.

Nearly all the values fell within the 90%

confidence interval (Figures 7.1.4-2 to 7.1.4-11).

It is assumed that the high flows associated with Tropical Storm Agnes (over 900,000 cfs) affected all the stations proportionally and the relationship between the control and other stations remained stable in this period.

After the model was verified, a new set of equations using the entire preoperational data base from 1967-1973 was developed (Table 7.1.4-5).

The 90% confidence intervals set on the observed and the estimated values from these equations serves as the "flagging" system for values that may deviate significantly.

The densities at each station in 1974 were estimated using the regression equations between the observed and estimated values at each station.

A plot of the observed versus the predicted densities showed a good agreement and nearly all the values were within the 90% confidence band (Figures 7.1.4-12 to 7.1.4-21).

Thus, it may be concluded that; (1) a significant change in the density of zooplankton did not occur at any station due to the operation of Units No. 2 and 3; and (2) the observed variations in zooplankton densities were due to natural causes.

The regression model discussed above helps detect the changes in density at each station.

However, it is important 7.1-31

also to know if the ranks of the stations changed between the two periods.

The Spearman Rank correlation test was used to determine this.

A significant positive correlation indicated that the ranks did not change significantly and the stations that yielded high or low densities in the preoperational period also showed a

corresponding high or low production in the postoperational period.

The Spearman rank correlation test also showed that the Stations that yielded high or low species diversity maintained the same trend in the postoperational period.

The zooplankton data from each station were further analyzed by stepwise multiple regression procedure to determine which physical factors affect the zooplankton density at each station.

The water temperatures, daily river flow and 'degree days* (temperature divided by river flow) were used as the independent variables.

In all cases (Table 7.1.4-6) a large proportion of the variance was explained by the variables.

However, the density of zooplankton at each station was affected differently by each variable.

For

example, at Station 601 (upstream control) degree day one and average temperature for the preceding five days were important.

In contrast, at Station 611 (farthest downstream station) degree day five and the average water temperature of. the preceding fifteen days contributed significantly to the variation in zooplankton density.

In all cases average water temperature had a positive effect (note sign of regression coefficients) indicating an increase in average temperature should enhance zooplankton production.

7. 1-3 2

I.

t l

~1

'!.'ABLE 7.l.~-1 Zooplankton taX4 collected from Conowingo Pond, 1967-1974.

H3b1tat designatiorui assigned according to Edmondson (1966).

Crustacea Cladocara Cope pod a Lcptodorldac: Lcptodora klndtii - llnnetic-lakca Sididae:

Dtaphanosoma leuchtenbcrgianum - ltmnetic-lakea Std* crystalline - littoral, weedy areas Latona aattfera - littoral-benthic Daphnl.dae:

Daphnla parw la - pond*, ema 11 lake.

D. retrocurva - ll.111netic-lakca

[. galeata mendotae - ltmnetic-lakes

!!.* pulex - ponds, lakea

!!.* ~

- ponds, lakes

!!.* amblgua - ponds, deep water of 1tratlfled lakes

~

afftnts

• pond1, pools

!:!.* macrocopa - ponds Certodaphnla lacu1trts - limnetlc-lakea

~* quadrangula - limnettc or littoral-lakes, pools C. reticulate - limnetic Scapholeberh klngt - weedy water - pool.s, lakes

~* !!!!!!!_ - weedy pool1, margta1 of lakes Slnoc:ephalu1 !!!.!!!.!.!!.!. - pool1, weedy pond*

Bosmlntdae: * ~

longirostris

• 11.ometlc *ponds, lake1

!* corogonl coresoni

• ltmnetlc *panda, lakaa Bosmtnopata detterst - ltmnetlc *ponds, lakes Macrothrictdae:

Ilyocryptus splnifer - bonthlc-poola, ponds 1* aordidu1

• benthic-pools, ponds Hacrothrix latlcornia - marahy pools, lake margins

!i* !'.!!!.!:!. - llttoral-atarshy pools, lake margin*

Cby.lorldae: Pleuroxus hamu1atu1 - llttora1 1 weedy water

!'..* danttculatus - littoral, weedy water Alona afflnls - marglns of lakes, ponds

• weedy water

~* guadrangutarts - 111&rglns of lake1, ponds

• weedy water

~* guttata - 1114rgins of lakea, ponds - weedy wsto~

!* ~

- margin* of lakes, ponds - weedy water Loydtgla quadrangutaris

• weedy lake margins Chydorus 1phaerlcu1 - littoral, llmnctic at times

£_. globoaus - lakea, panda *weedy 1113rgina Camptoccrcus rectiro1trl1 - weedy mar3tns of lakes

!S!!!!!!. latlssima - pools or weedy margins of lakes Eurycercus lamellatus

• pools or weedy margins of lake1 Alonella ~

• pool* or weedy margiua of lakea Cyclopotda ~

varicaus rubcllus - debri, weedy areas, pond*

Cyclop* vernalb - ltmnetle, 1DSinly warm water

£* blcuspldatua ~

- limnetlc, mainly cold water

c. scutifer - limnettc

• cold water Mesocyclopa eda~ - ltmnetlc, warm water F.ucyclops asllls - littoral

~* speratu1 - littoral tropocyclops pr**lnus

• ll~netlc Paracxclops fimbrlatus e.22E!!. - littoral-benthlc-lakes, pool1 Hacrocyclops ~

- littoral, benthic-lakes, pools Calanolda - Diaptomldae: All llt11t1etic

• lakes, ponds Dtaptomus pallidus

!!.* pygmaeua D. sictloldes Harpacticolda - littoral*benthtc Nona identified 7.1-33

[

TABLE 7.1.4~2 i\\nnu<1l species cornpodtion 0£ :z:oopl3n'kton (nu:nber per liter) in Conorlngo Pond, 1967-1974~

Year Species Leptodora ~

Diapha.nosoma leuchtenbergianum

~

crystallina Latona setifera Daphnia spp.

Moina spp.

Ceriodaphnia spp, Scapholeberis kingi

s. aurita Sim~lus~

~

longirostris Bo&111Lna corcgoni BDSiiiiiiOpsls deitersi llyocryptus spp, Macrothri>< spp, Pleuroxus spp.

1967 5.331 9.099 19.378 0.005 5.659 0.075 Alona spp, 0,093 Leydigia sp, 0.040 Chydorus spp.

0.073 Cainptocercus rectirostris

• Kurzia latissima

~rcus lamellatus Alonella e:<cisa NauplU ---

Cyclopoid copepodids Cyclops vernalis f* bicuspidatus ~

C, varicans rubellus C, scuti fer Mesocyclops edax Eucycloos agilis

~* speratus Tropocyclops prasinua Macrocyclops ~

Paracyclops fimbriatus

~

Orthocyclops modestus

~

copepodids D1aptC!l'l1us spp, Harpacticoida 40.630 10.432 5.479 0.321 0,419 0.312 1968 0.174 13.380 10.008 l.883 0.056 l.804 0.014 0,037 56.771 10,164 2.960 0.442 2,368 1.544 1969 0.050 4,908 7.192 2.286 0.165 0.005 5.891 0.07l 0.031 0.025 0.021 0,041 0.011 0.016 0.002 29.130 7.611 l,604 0.284 0,001 o.ou 0.125 0.011 0.001 1970 0,036 9.667 9.812 1.457 0.415 0.001 5.li50 0.007 0.012 0.024 0.003 0.013 0.008 0,013 0.003 0.001 24,629 6.416 2.187 0.001 0.879 0.001 0.017 0.082 0,045 0.002

'IOTAL 97.346 101.605 59.494 61.181

• Leu than,001 7.1-34 1971 0.085 8,727 7.913 1.429 0.762 7.127 1.006 0.010 0.007 0.003 0.010 0.004 0.022 33.349 7.171 1.214 0.001 0.717 0.003 0.002 0.018 0.001 0,554 0.204 0,005 1972 0.017

1. 794 1.955 1.178 0.033 1973 0.037 4.016 1.690 0.342 0.010 2,975-0.844 0.022 0.054 0,007 0.019 0.002 0,003 0.001 0.009 13.334 3.748 0,783 0.001 0.243 0.001 0.001 0.006 0.121 0.055 0,003 0.012 0,003 0.001 0.002 0.003 0.004 8.172 1.982 0.621 0.001 0.061 0.001 0.001 0.001 o.os8 0.020 0.002 1974 0.051 2.394 5.813 0.185 0.040 3.G68 0.490 0.003 0.001 0.002 0.002 0.006 Total 0.450 50.217 ~

53.482.

25.138...,

1,486 0.006 33.418 '

1.650 0.012 o.176 0,057 0.041 0.196 0,074

• .*0.133 0.003

• *"* 216.713*

'.J.,

• *:.., -;~;*t'J~ J

• 10.698 5.673 1.545 0.002 0.094 0.001 0.012 0.067 0.035 0.002 16.393 0.006,. ____.

./ * '**

3.041 0,006 0,005 o.oss 0.012 0.001 J. 794 2,226 0.015 70,344 26,311 17,938 30, 784 465,003 I

• ~

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TABLE 7. l.4-3 Comparison of the monthly dendty of coamon t&X4 of zooplanktan (number oe organisms per liter) durtog th* preoperational (1967-l97J) aod poatoperacional period* (1974) in Conawingo Pond.

Mmth Jan Fcti Mu Apr Kay Jun Jul Aus Sep Oct No*

RauplU 1967*1973 Q,06 0.04 0.07 0.14 0,25 11.04 33.32 52.60 40.30 19.70 o.ss 1974 0.06 0.01 0.19 0.43 71.89 3.92 23.10 16.8S 8.32 1.63 Cyc:lopoid cooepodids 1967-1973 0.01 0.02 0.02 0.03 0.07 5.40 7.07 11.tts 8.73 S.57 0.24 1974 0.03 0.01 o.os 0.49 43.81 2.85 9.00 4.71 2.67 0.93

~102s ve'l:Tlalis 1967-1973 o.oo o.oo 1.24 2.68 3.28 2.43 1.01 0.18 1974 o.oo 0.02 6,09 1.75 6.53 1.40 0.62 O.Jl Daphnh 1pp.

1967-1973 o.ot 4.54 8.43 10.58 12.56 3.63 o.os 1974 0.13 14.05 9.82 23 *.57 8.17 7.33 0.68 Boamina longiroatris 1967-1973 0.01 0.01 0.03 0.22 3.31 2.13 7.31 11.54 4.59 0.16 1974 0.03 0.01 0.87 4.95 1.81 2.09 18.08 a.so 1.94 Dia2hanoaoma leuchtenbergianum 1967-1973 o.oo 2.15 12.59 14.80 8.41 0.93 1974 o.oo o.oo 0.68 6.97 13.62 3.12 0.02 0.06

• LeH than 0,01 TABLE 7.1.4-4 Comparison of the monthly total zooplankton deostty (number of orgaui11111 per liter) during the preop*rattoaal (1967*1973) and postoperational (1974) periods in Conawtngo Pond.

Jan Feb Mar Apr 1967*1973 o.u 0.08 0.11 0.23 1'74 0.16 0.10 O,JO May Jua Jul Aug Sep Oct 0.61 33.59 72.79 106.04 89.15 37.07 2.oz 143.16 27.43 62.4S SS.39 29.75 7.1-35 Nov 1.19 6.26 Dec:

Annual 0.30 13.20 0.24 u.s2 0.13 3.23 0,03 5.87 0,90 1.S2 3.32 S.80 0.17 2.46 0.07 J.49 3.24 2.22 Dec:

Annual 0.95 28.49 0.37 31.58

t:

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'!'!\\*I(;*: 7.l,!J-$

t:hloruph)'ll :! (mg/~) nJ.tt':it~.:1. phasph11cc1 (p11111J, w~tct' t¢r:'pcnturc (r), f.lnlly rlv~r: Clov (x lOOO ch) ~nd zoopbnk.toa dcnd.ty (no,/Lltcr) dau d\\ltlnr. thu proapor.auon.:.l (l97L*LIJ7)) and po:1tupcr:1tl~nal (l97!*) t'li'rludJ la Cooowi.ngo Pond.

ill!

19 1'br*2l ".lr 1.11.

18 !".Ay 5.4..

s.9:?

9 Jul IZ.46

&.08 ll Jul 16,20 3.60 4 Au11

\\6,36

4. ll 18,\\u~

22.46 2.97 l Sup lo.n 6.04 13 Si:p Ll.26 S.07 29 S*p 10,57 8.36 u °"'

ll. S3 8.72

'.?.1 Oct 9.29 13.42 10 llav ll. 50 10.74 24 1'oY

\\Q,%

7.08 u De~

4,37 7,44 1972 10-U Jon 0,55 6,95 31 J~n-3 Fcl>

0.52 8,21 13 Apr l,39 4,97 28 ~pr

2. ll 4.04

---

10 !by...

4,74_

6.23 24 nay 13.7' 4.25 8 Juft n.i; 4.47 21 Jun 11.l 7,31 6 Jul l.i

~.?6 19 Jul Jl.8 6.75 z.\\us lJ.8.

5.34 16 Aug 18.?~

7,97 30 Aug 2l,6S 1.00 13 Sc~

16.39 1.5.19 27 Sep 13.22 S,'7 16 Oct 25 Oct-31 Oct 22,87 7.11 9 ~ov-10 Nuv U,99 7.20 16 Nov 3.41 6.31 5 Dec l.7:.

>.. 42 111 Doc l.'2 5.05 llli 25 Jan l.09 s.r.3 7 Fcl>

1.29 4.~7 7 Mar 2.38 S,29 28 liar 1,58 4.25 U Apr l.89 4.SS 24 Apr LO,ll 5.31 8 !10y-? 11ny

.??.56 4.LO zz May l6,49 J,61 5 Jun 21,77 4.12 20 Ju11 2?,22 l,U 4 Jul 19,14 5.48 18 Jul 10,09 4,41 31 Jul 14,17 3.39 1,,\\qg 12.56 1.10 29 Aug l8,34 2.90 12 Sep 11.10 2.22 26 Sop 26.31 5.4; l4 Oct l0,91 4,03 12 No*1 4,51, J.42 28 Nov 4.77 12 Dec 8,45 2.48 1974 24 J~n 1,12 8,68 l.5!'.4r 1.~

5.27 26 liar z.22 s.as 9 Apr 6.85 3.78 25 Apr 5,07 4,96 8 !\\ty 38.11 3.86 22 :-'.ay 33.38 2.91 o.os o.os 0.29 0.09 0.14 0,06 0.16 0.10 0.09 0.23 0,06 0,34 O,Zl 0.26 0.11 0,24 0.22 o.a9 D.19 0,02 O.ll 0.06 0.02 0.05 o.os 0.06 0,08 0,14 0.16 o.za D.13 0.17 0.10 0,36 o.oa o.u 0.16 o.u 0.13 0,09 0.09 o.u o.2s 0.12 0,09 0,13 0, 12 0,17 0.10 0.10 0,09 0.12 o.u 0,09 o.u 0,23 0.28 0,28

\\lator r... p.

(Y) 39,2 60,Q 86.0 U.3 76, 7 82.4 73.6 8~. l 10 *.;

64.l 62.5 48.2 "4.3 42,5 34.7 n.2 50,9 SJ.3 sa.1 70.7 71.1 73.8 68.9 n,9 77.9 78,6 81,5 75.4 71.6 64.4 n.1 51,3 39.2 33,1 li.4 39,3 46,6 46.3 63,5 57.4 58,1 69,5 72.2 77,9 79.4 82, l BJ,O 78,S 79,2 66.2 59,0 43.7 50.4 3'.2 38.4 40.3 43,2 46,8 56,2 58.3 River Avg. toc-11 rtw ZOOf' \\ankco...

lk1t1Lcy 173,1, 0.1 61.9 0.1 7.7 Ul't.3 6.7 L?4.9 n.4 67.S 7.3 166.9 7.7 Ul.1 lJ. L t42.9

13. ?

ll.6 10.2 za. 1 16.J ll.5 17.8 l.2 l2,0 l,J 107,0 2,0 39,4 0.1 ll.6 O.l 49,5 0,l 71.0 0,J

~91.1..---. -- 0.4~

58,3 0.6 4-<,6 2.6 54,S 6.4 76,J 0,9 S7,6 2.8 16,S S9.l 14.0 B6,2 9,r.

U0.6 6.7 81.9 8.0 1,1.s a.a 70,7 7.1 JZ,9 62.7 2.1 so.s 0.2 s5.7 0.1 117.&

0.1 60.5 0,1 51.l 0.1 ll7.6 a.J 37,4 0,2 40,2 0,J 62.S 1,0 4S,l 1.0 24.5 26,8

~o.. o

7. 7 13.2 66.l 17.0 95.l LO,l 68.0 11.3 39.4 8,9 51,6 17,7 4.3 U,9 16,3 Zl,4 0,2 29,3 o,3 105,2 0,8 lll.2 O.L 69,S O,l 51,9 O, l lU.4 O,J 43.3 O,J 29,5 0,8 0,28 70,9 40,3 3,2 S_Ju~ _______ 36,80 __

z.J6 __

0.zs_10.1_~22..& ___ i.1.o 19 Jun Zl, 92 1,38

.O. H 76.l 26,0 244.4 10 Jul n.oo 2.57 0.21 83,?

26,5 20.5 24 Jul 15,Sl

~.aJ 0.24 83,5 l0,5 34,4 14 Aug 15,77 2.10 0,L9 82.4 8.4 60,8 29 ;\\U~

12,88 2.11 0,15 86,6 6.l Lfl4,1 11 Sop J?,:13 2.4, 0,21 70,fj 2i.o 10.7 24 Stp 22.38 2.76 0.23 71.6 20,0 100.1 9 lkt

)9,~0 2,32 IJ,23 6Q,3 U,6 30.6 23 Occ 12.96 2.74 0,18 57, l ll.4 29,0 6 ?iuv 16.!14 2,42 0.21 61.6 7.6 12.l 20 ~io-1 9,37 2.28 a.tr.

43.9 23,7 0,4 5 Dee 4,05 3,04 0,23 36.j ll,2 0,4 15 Jlcc* 16 Pee 4,31 3.27 0.23 38.3 59,9 0,3 7.1-36

-~

~

~

.-~*,....,...,. ___ _...,......,_,....,,....,

~

.I

~ '.

J *'.*

• • 1

..f:

..,_~*-

TABLE 7. l.4-6 llegression ectuations for predicting zooplankton densities at Stations 602-.611 (dependent variables} in Conowingo Pond. Equations based -on data from Jan-December, 1967-1973.

Equation 2

R.

L 602 * *0.0948 + 1.0779 L 601 0.8842 L 603 * -o.0563 + o.8744 L 601 + 0.0443 DJ o.9114 L 604 * -.3485 + o.9676 L 601 - o.oos2 F l o.8991 L 605 * *0.1812 + 0.8838 L 601 + 0,0191 T l3 0.8936 L 606

• 0,0091 + 0.8145 L 601 + 0.0201 D 8 o.9158 L 607

• o.4195 + o.7489 L 601 - 0.0056 F 1 + o.1937 D l 0.8910 L 608 * -0.0127 + 0.8740 L 601 + 0.1590 D l o.8956

1. 609 * -0.1942 + 0.4946 L 601 + 0.0271 I 13 + 0.2349 D l o.eso9

'L 610 ** 0.1102 + 0.4325 L 601 + 0.0523 T 15

• 0.0059 F 10 o.9214 1L 611 * -o.3046 + o.4129 L 601 + o.0649 t 15 0.9118 w

L 602

• log of zooplankton dendty at Station 602 J Dependent variables L 611

• log of zooplankton density at Station 611 L 601

• log of zooplankton density at Station 601 r l

• average daily river flow on the day of sample taken F 10

• average daily river flow for 10 days before sample was taken D l

• degree day 1 D 3

• degree day 3 D 8

• degree day 8 T 13

• average of 13 days water temperature before sample vaa taken T 15

• average water temperature of 15 days before sample was taken 7.1-37

• 7.:ic o.2s26 0.2445 0.2727 0.2689 0.2312 0.3062 0.2750 0.3090 0.2659 0.2607 Independent variables

' \\*.

j TABLE 7.1.4-7 Regression equations between the total zooplankton density (log (x+l) at Stations 601-611 and average water temperature and degree days (water temerapture divided by average river flow) in Co::7.owingo Pond, 1967-1973.

Equation L 601 = -0.0485 + 0.0879 D5 + 0.0194 Tl L 602 = -0.1139 + 0.1241 D4 + 0.0174 T4 L 603 = -0.1439 + 0.1613 D3 + 0.0216 T4 L 604 = -0.1204 + 0.1688 D3 + 0.0253 Tl5 L 605 = -0.2247 + 0.0455 D8 + 0.0378 T4 L 606 = -0.1629 + 0.0528 D7 + 0.0327 Tl2 L 607 = -0.1690 + 0.4117 Dl + 0.0427 Tl4 L 608 = -0.1920 + 0.2249 D2 + 0.0306 Tl5 L 609 = -0.2066 + 0.2101 D2 + 0.0383 Tll L 610 = -0.3403 + 0.0641 Tl4 + 0.0205 Dl4 L 611 = -0.3104 + 0.0709 Tl5 + 0.0386 D5 2

R 0.7895 0.7454

o. 7814 0.8102 0.7960 0.7890

o. 8021

o. 7701 0.8426 o.sns 0.8857 L 601 : log density of total zooplankton at Station 601 D 5 = degree day five (average daily temperature (C) )

average daily river flow (cfs)

---

!.r~l~*--averai;e daily water-temperature- (C) -on--day--1~--~------

., ~-.

.. *** i

• \\., *,.

7.1-38

J

. t l

i l

j

.~

~.

.J l

300 100 10 1

0.1 300 100 1971 1972 Zooplank.ton (No./liter)

Temperature (F)

.. now cf s lt 1000 r*

.................... '\\

200

\\

'~..

'\\

150

\\

100

\\

\\...

\\

\\ ' :

,~..

w-!'"""\\

so

\\

I. '

\\~............... ~****'

o..

1973 1974 F'I'.Jil RB 7. 1.4* l Plot of total zooplank.ton density (nl,lll\\ber 2er liter}, average daily river flow (1000 x cfa) and water temperature CO iT\\ Conovingo l'ond, lHl* 1974.

7.1-39 90 70 so 32

lt.OO 3.20 1.60

_ :-~~~ o.eo o.oo I I' r*.*

r*

4.0(1 l '.*

3.20 2.40 1.60 o.so o.oo Station 602 4.00 StatiOll 603 3.20 2.40 1.60 o.oo 0.17 0.67 1.17 1.67 2.17 2.67 0.67 1.17 1.67 2.17 2.67 Station 604 3,00 Statio!l 605 2..40 1.80 1.20 0.60

-o.oo

-0.15 0.45 l.OS l.65 2.25 2.as 0,45 1.05 l,6S 2.2s 2.as

-.' I.

Fim!RE 7.1.4-2 1.'he 907. confidence intervals on the obaerved va estimated deusitiea of total zooplankton at Stations 602-605 in Conowingo Pond.

7.1-40 I "

r

. r.

1:1" :

!it.

f;~ :*.

l*.4

~s;'l *

~.}

!*:)'

~;

i'".

lj*.;...

+

i~ !

ill c

1\\'..

• ~

~* :

• ~,.

i::

2.60 3.10 Station 606 Station 607 2.10 2.so 1.60 1.90 1,10 1.30 0.60 0.10 o.oo 0.10 0.11 0.67 1.17 1.67 2,17 2.67

-o.1s o.-4S 1.os l.6S 2.25 z.as 3.00 Station 608 4.00 Station 609 2.40 3.20

-:-* 1.80 2.40 1.20 1.60 0.60 o.ao

-o.oo o.oo 0,17 0,67 1.u 2.67

... ~ *,

F'IGURE 7.1.4-3

-o.1s o.4s l.os 1.65 2.2s 2.85

'l'he 90i confidence intervals on the observed vs estimated densities of total zooplankton at Stations 606-609 in Conowingo ~cud, 7.1-41

1.

) '

Station 610 4.00 Station 611

-0.15 0.45

,1.00 1.6' 2.15 2.85

-0.15 0.45 1.05 1.65 2.25 2.85 Fir"iUnE 7. l.1.i.-4

'It.a 90t confidence intervals on the observed vs estimated densities of total zooplankton at Stations 610-611 1 in Conowingo Pond, 7.1-42 l

i I

i

r1,*~rr*

~**..

t.*.

~...

F*

f *.

7. 1. 5 BENT HOS 7.1.5.1 Species composition From 1967 through 1974 (Table 7.1.5-1),

61 taxa were collected from the Pond.

The major types are oligochaetes and chironomids.

The common taxa are

~!mnQQfil£§ hQ!fm~!§t§!i,

£rQ~1~di~§ sp.

(complex),

~h~QQQf~~

Qgn£~i2gnni§,

£hifQDQill~§

~~!~!1Y~~£§,

£Q.§lQ~~nYE!:ll!. £QU§!UUY§ and IlYQ£r!1£2 £gmE1gt2!1i (Table 7. 1. 5-2).

These taxa comprised 94 to 98% of the total individuals collected in various years.

He~~ggni~

liIDQ~t~ is infrequently collected and its density never averaged more than 0.01/81 in.z at any station or in any month.

Few fresh water mussels are present.

No rare or endangered species of macro-invertebrates exist in the Pond, nor do species commercially harvested for food or bait.

7.1.5.2 Species Diversity and Equitability The benthic community in the Pond is characterized by a

small number of species which account for most of the individuals.

This may be due to the bottom types.

Two major substrate types are present in the Pond, sand-coal fines and silt (particles~u500) (Table 7.1.5-3).

The species diversity (D) was calculated frorn the following expression, i

i=1 log p

2 i

where p. = proportion of the i 1h taxon.

The benthic community is sparse as indicated by the low species diversity (D) indices (Table 7.1.5-4 and 7.1.5-5).

Most values (over 90%) of D were less than 2.5 throughout the year and at a given station.

No substantial differences were noted in D values between the preoperational (1967-1973) and postoperational (1974) periods.

The diversity values are influenced by the proportion of the common taxa.

The importance of the number of taxa in the index of diversity was determined by plotting values of D and corresponding number of taxa in the samples (Figure 7.1.5-1).

The monthly species diversity data given in Table 7.1.5-5 were used.

The correlation coefficient was nonsignificant

• ( r = 0.098, P~0.05).

Although the range in number of taxa

7. 1-4 3

I

i. !'

~':--,

collected was large, its influence was not discernible.

We conclude from this analysis that if any additional uncommon taxa are collected they will have little or no effect on diversity, which is determined primarily by the abundance of the most common taxa.

The equitability index (E) was calculated from the following expression, E =

D Log 2S Where D = species diversity, S = number of taxa, E = equitability (evenness of the species).

The values of E can range from 0

to

1.

A value of_ one indicates that alL the_ taxa occur in equal-proportions in the samples while a value of zero would indicate extreme inequality.

overall, the equitability component has remained similar between years; the values ranged from 0.42 to 0.53 (Table 7.1.5-4).

However, some seasonal differences were noted (Table 7.1.5-5.

The values appear to be higher in the fall through spring (more evenness) and lower in the summer (less evenness).

The values also varied with stations (Table 7.1.5-4).

Species appeared to be somewhat evenly distribu~ed at all stations only in 1967 and 1973.

In other years variation was large.

The influence of the number of taxa on the equitability was determined by plotting the number of taxa against the equitabili ty index (Figure 7. 1. 5-1.).

The plot shows that the relationship is negative (r = -0.505, P::50.01).

That is, the equitability increases with a

decrease in number of species, particularly the uncommon ones.

This is expected since th~

additional species in samples are lower in abundance and thus decrease the equitability but do not increase the species diversity.

Addition of uncommon species simply increases the denominator log2 s.

t*:' {

• t'.

In general, the analysis indicates that the species

f.

diversity index is inadequate and insensitive to the occurrence r..

of uncommon species and is influenced more by the relative

~.

proportions of the dominant species.

consequently, the addition or elimination of an uncommon species would not be reflected in

-~:~.~~-'I.the D values-unless a change has also occurred in-the proportion------*

• ~*

of the dominant species.

Changes of small magnitude in the r

equitability component may not be interpreted as real changes in

~'

the cornmuni ty due to any environmental deviations.

A high l;:

correlation exists (r = 0.881, P::50.01) between the species

~

diversity and equitability.

I

~..

~*..

7.1-44

I 7.1.5.3 Distribution and Abundance Although the common taxa (selected representative indigenous species) are widely distributed in the Pond, their densities vary between stations and years (Table 7.1.5-6 and Figures 7.1.5-2 to 7.1.5-5). overall the density of g~Q£l~Qi~

was highest at Station 611 in the preoperational years (1967-1973) but in 197~ its density was highest at Station 601 (upstream from the PBAPS discharge)

• At Station 605, which is located in the plume, no changes were observed.

The densities increased at all stations except 605 after 1972.

The density of

~*

hoffmei§~g~i decreased considerably in 1972 and 1973 at all stations.

However, in 197q the densities were close to or higher than those in 1967-1971.

The density of ~haQ£Q!~§ was higher at Stations 610 and 611 and lower at Stations 602 and 606.

However, its density appeared to have increased at Station 608 and decreased at Station 605 (located in the thermal plume).

tl~~ggn!~ were collected too infrequently and in Jow numbers to reveal any trend.

None have been collected from Stctions 610 and 611 (Figure 7. 1. 5-5)

• The Spearman rank correlation test was used to determine if the ranks of the stations with respect to the abundance of

~!ill~Qdr!lY2 hQ11m~!§~~~~, E~2£1~9!Y§ sp. (complex) and ~haggorus 2!ill£til2~nni~ had changed between years (Table 7.1.5-7).

Since the eleven monitoring stations were not sampled in all years, the data used for the analysis were those from years when all stations were sampled (1968, 1970-1974).

The test was not run for He~~g~n1~ 1!mb~~~ because its distribution is limited and its abundance is low.

Only one significant (P<0.05) correlation was noted for timnggri!Y§ h2!!m~ist~!i (between 1972 and 1973) and for froclagi_g§.

sp.

(between 1970 and 1974)..

Ranks of stations varied greatly in other years and no trend was apparent..

A positive significant correlation for ~-

hoffmei§!~!! indicated

~hat stations that had high or low abundance in 1972 maintained the same trend in 1973.

A significant negative correlation for R£Q£1~9i~§ sp. indicat~d that the stations that yielded high or low abundance in 1970 generally were reversed in their ranking in 1974.

Although more positive significant correlations were observed for ~h~ObQf~~

2Yn£!!Q~DDi§, no consistent trend was apparent.

The postoperational year (197q) was significantly correlated only to 1968 and 1973.

The lack of a

consistent pattern in the case of

~*

2Yn£t!2~nni2 and large amounts of variation for t* b2!~mei~!gr! and frQcladiu§. sp.

may be partly attributed to the lack of samples at all stations in each month in each year.

7.1-45

~

f. !.

~".:,...

[<

r~ 6.

r* *

~;

~

t;.,

t~.

~l; f' I..

t.

t~ : '

~-

c*.

• '\\,

.I.

7.1.5.4 Faunal similarity The f aunal associations at each station were similar in all years.

The percent similarity indices (PSc) between years at a

station showed that the stations maintained similar f aunal associations through 1971 (Table 7.1.5-8).

They showed less similarity with previous years in 1972 and 1973.

However, PSc values were similar between 1972 and 1973.

Station 607 and 611 remained relatively similar in all years.

Station 605 (located in the thermal plume) showed intermediate to high similarity in all years.

7.1.5.5 Biomass The biomass varied between months during the preoperational (1967-1973) and postoperational (1974) periods (Table 7.1.5-9).

No consistent _ trend was ~~ evident.

The postoperatioral biomass was higher only in January and April and was within the range observed in other months of the preoperational periods.

7.1 - 46

.. / :.:_

~ ; '

TABLE 7.1.5-1 List of benthos collected in Conowingo Pond, 1967-1974.

Platyhelminthes Nematoda Bryozoa Mollusca Pelecypoda Gastropoda Scientific Name Planariidae Dugesia sp.

Plagiostomidae Hydrolimax grisea Plumatellidae Plumatella sp. (Statoblasts observed)

Lophopodidae Lophopodella carteri (Statoblasts observed)

Pectinatella magnifica (Sta to blasts observed)

Sphaeriidae Pisidium sp.

Sphaerium sp.

Unionidae Utterbackia imbecilis Lymnaeidae Stagnicola sp.

Physidae Physa sp.

I Annelida Oligochaeta Polychaeta Hirudinea Arthropoda Crustacea Arachnoidea continued Tubi ficidae Branchiura sowerbyi Limnodrilus hoffmeisteri

!lyodrilus templetoni

!sopoda Asellidae Asellus militaris Amphipoda Gammaridae Gammarus sp.

Talitridae Hyalella ~

Hydracarina 7.1-47

TABLE 7.l..5-1 Continued.

Insecta Odonata Hemiptera Ephemeroptera

~etidae Scienti fie Name Baetis sp.

Ephemeridae Hexagenia sp.

H. limbata Caenidae

~sp.

LibelluiUdae Gomphidae Gomphus sp.

Hesove liidae Mesovelia mulsanti Megaloptera Trichoptera Coleoptera Diptera Sialidae

-- Siaiis sp, Leptoceridae Oecetis sp.

Psychomyiidae Hydropsychidae Cheumatopsyche sp, Elmidae Dytiscidae Hydrophilidae Culicidae Chaoborus pupae g, punctipennis Ceratopogonidae Chironomidae Pupae Procladius sp (complex)

_f. riparius P. culiciformis P. rubetlus Anatopynia sp. (1)

Tanytarsus sp. (1)

Chironomus sp.

c. attenuatus

£. (Dicrotendipes) sp.

Tribelos sp.

Cryptochironomus nr ~

C. nais Har~hia sp.

H. nr nais

![. amacli2e'rus Pentaneura sp. E Pentaneura sp. *~~~~~~~--~~~~~-~~~~~~~~~~~~~

Polypedilum halterale P, fallax Coe~us concinnus Limnochironomus sp. (l)

L. fumidus L. modestus Calopsectra sp. 5 Glyptotendipes sp.

Orthocladius sp.

Microtendipes sp, Psectrocladius sp.

Anthomyiidae 7.1-48

~**.:.

'fA '"\\Li:~ 7. l.~-2 Meaa llUnlber (per Ill ta. 2) and 'Perca11tage comiiodtton of bnthic organi.,.. collected duriu.1 pr*operatioo&l (1967*1,13) and poecoperational (1974) p*tlocla, ta Conov11110 Pand.

tear lfo, Smple*

l~cladiua *P* (complax)

J.imnodrilua hofflnei1teri.

Chaoborus punctbennh Iboclrllua templetoni Coelot.... ypu.t concfnnua Polypedllum halterale SphHtium Ip.

2!..5!.tl! Ip*

T*11f!lr9UI *P.

!!ydrollawt *'P*

Camania 1p.

Cael\\ia Ip, P1nt11n1uTa *P* E Cohoptera J!nnbchta *P*

coatS.-4 Mull !lo.

'I: llo.

Kean No,

'Z. 11o.

Heaa Ho.

'Z. No.

K01n !lo.

'Z. !lo.

1'1!a11 No,

'Z. llo.

Hun No.

'Z. No, Mean No.

1 llo.

tie... No.

'i Mo.

Kaan No.

'Z. No.

Kua )l'o,

'J. Ho,

!foae No.

'Z. No, Meu llo,

" llo.

1'1!&11l10,

'Z. Ro.

Me&11 No,

'Z. !lo, Meaa Ro.

'Z. Ila.

ltaan No.

'%. !lo.

Hua Ro.

'Z. llo.

'MH!l Ito.

i Ko.

1%7 92 1.56 5.6 115.45 sa.e 0.56 2.0 0.52 1.9 7.12 25.4 0.21 1.0 0.04 0.1 0.33 1.2 0.30 1.1 0.21 0.1 0.07 O.l 0.01 Tl.

0.18 0.7 0.01 n

o.:n 0.7 0,0%

0.1 0.01 Tll 0.06 0.2 0.02 0.1 0.01 tit o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo 0,0 1968 1969 1970 98 75 19&

3.53 a.u 3.1a 10.5 14.7 8,2 14.86 26.85

24. 72 44.1 48.0 64.0 5.97 2.25 1.24 17.7 4.0 3.2 0.9.5 2.44 1.52 2.8 4.4 3.9

'*~

11.63 5.7.5 18.S 20.a 14.9 0.11 1.84 1.45 o.J 3.3 3,8 0.06 o.09 o,oo 0.2 0.2 o.o 0.23 0.43 0.29 0.1 o.a 0.1 0,03 0.16 0.02 0.1 0.)

0.1 0.29 0.8 0.01 0.1 0.15 o.s 0.12 0,4 o.oo o.o 0.24 0.7 0.08 0.2 0,37 1.1 0.14 0.4 o.oo o.o 0.10 0,)

0.01 ti.

0.01 tit 0.01 n

0.01 n

0.02 0.1 7.1-49 0.01 0.1 0.00 o.o o.oo o.o 0.1.5 0.3 o.oo o.o 0.27 o.s 0,53 0.9 0.78 o.s 0.01 Tll o.oo o.o 0.)5 0,6 0.03 ta 0.01 Tl o.oo o.o 0.25 0.5 0.01 Tll o.oo o.o o.oo o.o 0.02 n

o.oo 0.0 0.02.

0.1 o.oo o.o o.oo o.o 0.01 T1l 0.03 0.1 o.oo o.o o.oo o.o 0.01 Tl.

o.oo o.o 0.00 o.o o.oo o.o o.oo o.o 1971 142 1, 7~

5.8 115.99 56.4 5.44 18.0 0.71 2.4 4.53 1.5.0 O.JO

1. 0 o.oo o.o 0.01

'II 0.01 n

o.oo o.o o.oo o.o 0.01 ti.

0.00 o.o 0.01 n

0.22 0.1 o.oo o.o 0.00 o.o o.oo o.o o.oo o.o 0.02 O.l 0.01 Tl 0.01 ta o.oo o.o 0.01 n

o.oo o.o 1772 233 5.44 22.7

9. 00

)J.4 2.51 l0.5 1.24 s.2 0,'Jl J.8 S.27 22.0 0,03 O.l 0.14 o.&

0.04 0.2 0.01 TR l'.11.

TR 0.04 0.2 TR ti.

0.00 o.o 0.01 IR o.oo o.o o.oo o.o 0.01

'1'l 0.01 TR o.oo o.o n

o.oo o.o 14.95 27.41 41.t 27.4 7.74 29.58 21.7 31.7 2.63 11.0 7.4 12.3

o. 2.5

2. 26 0.7 2,4*

%.80 5.91 7.8 15.)

6.00 13.68 16.8

14. 7 o.ia o.30 0.5 0.3 0.28 0.4&

o.a o.s 0.07 o.u 0.2 0.2 o.oo 0.01 0.0

. Tit:.

o.09 o.04 o.z **.* Tll ~'

O.Ol.

n

. n.....

. *.

o:: ::~

0.02

. 0.04 !

0.1 n :.*..

0.12. o.o(.:

O.l

n.

0.02.. 0.06 0.1 0.1

• I".

0.07 0.76 0.2 o.e 0,22 0':15.

o,,

0.2 o.oo o.o ti.

0.01 0.03 TR n

0.07 0.11 0.2 0.1 u

n 0.06 0.01

o. 2

'fl o.co ti o.o 0.00 o.co o.o o.o

1*

TABLE 7.l.5-2 QoQtia111d.

Year 1!9, S!!llJ!lU

(:j\\lopuctu ap, !I J!ewenia *P*

PToeladlus rlparius Procladlu.a cullcl fo'n!les llaetl* ap.

Keaa No.

"Na.

lleu llo,

" Na.

Heu No.

" No.

Mean No.

1. llo.

Meu No.

1. !lo.

1967 82 o.oo o.o o.oo o.o o.oo o.o o.oo o.o 0.00 o.o o.oo o.o o.oo o.o l'ean No.

0. 00 i Ko7 - -

o.o Sphaerild.ae Cr/ptoch1Tonocus nats Limnochlrcnomus fur.lldus Clntotendipu ~

Clrptotendip&s sp.

Stagdcota *P*

Chlronomus (Dlcrotendipu) *p.

Byale\\la *P*

Ch1ronomidae Polnedllum faltu.

ChlTonomua (Trlbelos) ap.

C.r.topagooid**

Mun l!o.

1. No.

Meu No.

'J. No, 11o&n llo.

'l No, Mean !lo.

1. No.

Mun No.

't,tlo, Hean No.

'l So.

Hean !lo,

'.\\ No.

Mean No.

1 No.

Hean No, 1 Ho.

Hun llo,

'J. Ho.

~an !lo.

1. llo.

Mean !lo.

1. No, o.oo o.o 0.00 o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o 0.00 o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o 1968 98 o.oo o.o o.oo o.o o.oo o.o 0.00

• 0,0 o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o 0.00 o.o 0.00 o.o o.oo o.o 0.00 o.o 0.00 o.o o.oo o.o o.oo o.o 1969 75 0.01 ta 0.08 ci,1 o.oo o.o o.oo o.o o.oo o.o o.oo o.o 0.00 o.o 1970 198 o.oo o.o 0.00 o.o 0.11 0.3 0.20 0.)

0.02 Ta 0.04 0.1 0.01 TR o.oo o.oo

.. o.o -

o.o o.oo o.o 0.00 o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o 0.00 o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o 0.00 o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o 1971 142 o.oo o.o o.oo o.o 0.01 Tll 0.06 0.1 0.02 0.1 o.oo o.o o.oo o.o 0.01 Tll 0.02 0.1 0.00 o.o o.oo o.o 0,00 o.o o.oo o.o o.oo o.o o.oo o.o 0,01) o.o 0.00 o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o 1972 233 0.01 0.1 o.oo o.o ta 0.03 0.1 0.02 0.1 0.00 o.o o.oo o.o TR 0.01 TR 0.47 0.1 o.oz 0.1 Tit 0.12 0 *.5 Tll TR 0.01 Ta o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o 1973 21,2 o.oo o.o o.oo o.o o.oo o.o o.oo o.o 0.01 TB o.oo o.o o.oo o.o o.oo o.o o.oo o.o 1974 211 o.oo o.o o.oo o.o o.oo o.o o.oo o.~

n o.oo o.o o.oo o.o o.oo o.o o.oo o.o 0.01 o.oo Tl.

o.o 0.00 o.oo o.o o.o 0.01 o.oo

'l'R 0,0 0.02 0.05 0.1 0.1 0.00 o.oo o.o o.o 0.01 o.oo TJI o.o o.oo 0.01 o.o

'tP.

0.02 n

n 0,00 Tl o.o 0.01 o.oo Tl O,O o.oo

'l'I.

0,0 0.02 0.01 0.1 TJl Tll TR.

____ 1.nchy0111yl.idae _______._111110.---0.00--0.00.-. - o.oo--o.oo---*o.oo--0,00--..--.- *-----

llani11chla nr !!!!!!,

llydrophll f.dae 1 !lo, 0.0 0.0 0,0 O,O 0.0

0. 0 Tit Tit Hean Ko,

1. llo.

Hean No,

" No.

Kun llo,

'I. "°*

Hl*n !lo,

\\Ko, o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o 7.1-50 o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o o.oo o.o n

0.01 Ta 0.02 0.1 TR.

0.00 o.o o.oo o.o 0.10 0.1 0.00 o.o

TA'DL£ 7.1. 5-2 Coiictoud, Tear 1967 1966 1969 1970 1971 1972 1913 1974

!lo. Sgle*

82 96 n

198 142 233 242 tll Tua l!!Ct'Ottndt~I *P*

HeaQ !lo.

o.oo 0.00 o.oo o.oo o.oo o.oo o.oo T. No, o.o o.o 0.0 o.o o.o o.o o.o TR.

Bydropaychldo*

Heall !lo, o.oo o.oo

0. 00 0.00 o.oo o.oo o.oo T. !lo.

o.o o.o o.o o.o o.o o.o o.o n

l'hyea op.

Kean llO.

o.oo 0.00 o.oo o.oo o.oo 0.00 o.oo T. No.

o.o o.o o.o o.o o.o o.o o.o n

Polychuta Koa.n !lo.

0. 00 o.oo o.oo o.oo o.oo o.oo o.oo 0.01

%. Jio, o.o 0.0 0.0 o.o o.o o.o o.o TR

~.!!:.!*I"*

Hean lfo, o.oo o.oo o.oo o.oo o.oo o.oo o.oo T. 110.

o.o o.o o.o o.o o.o o.o 0.0 TR Q)el!IO&toe*:.:che *P*

t""'*n ?lo.

0. 00 o.oo 0.00 o.oo 0.00 o.oo o.oo 0.37 T. !lo, o.o o.o o.o o.o o.o o.o o.o 0.4 PaectToc hdl.ua ap.

Mean Ro.

o.oo o.oo o.oo o.oo o.oo o.oo o.oo 0.01

't No.

o.o o.o o.o o.o o.o 0.0 o.o Ti\\

~*I"*

Haan No, o.oo o.oo o.oo 0.00 o.oo o.oo o.oo T. !lo.

o. ~

o.o o.o o.o 0,0 0.0 o.o

'l'R Ube llulidae

!!ean lio, o.oo 0.00

0. 00 0.00 o.oo o.oo o.oo T. 110.

o.o 0,Q o.o o.o o.o o.o o.o tR total*

He411 No.

27.96 33.65 H.99 38.64 30.15 24.34 3.5. 70 93.16 T. No, 99.9 99.8 100.0 99.9 100.1 1~.l L00,0

~9.6

• .. < 0,01/81 la. 2 ti. * <,lOl.

~= :

• * * ~

7.1-51

TARLE 7.1.5-3 Percentage coc:poaltton of p3rt1cle size (microns) tn bottom aedimenta at lillnologtcal atatio111 in Conovingo Pond, 27 July 1972.

PRrtf.cle she {"'f.c:ronl 3360 2000 1000

!iOO 250 125 63

<Sl Station.

601 0.4 0,9

.5.6 36.8 21.4 14.4

.5.2 1.5.3 602 Tr Tr tr 0.1 0.2 1.3 7.8 90.5

---

O.a ___ ~ a:& **---

-~--~-~

603 *---1,9 --T.6 ---10.7 -~,--

24.2 1.2 604 0.2 o.s 19.3 29.8 17.7 23.6 3.6 S.4 605 Tr Tr tr 0.1 0.4 2.7 7.4 a9,5 606 Tr 0.1 1.3 13.5 52.6 30.2 0,9 1,4 607 0.1 Tr o.s B.l 23.6 41.8 l.5.9 10.0 608 0.1 0.1 0.1 0.4 1.8 5.4 6,S 8.5,6 609 0.1 0.1 0.2 0.3 1,8 S.3 7.7 14,S 610 0.1 0.2 1.8 9,6 9.7 13.6 19.9 48.4 611 tr Tr Tr Tr 0,6 9.7 16.9 72.7 Tr

• leas than O.l percent 7.1-52

-~

TA5LE 7. l. 5-4 Species diversity (D) and equicability (E) indices for benthic organisms at Stations 601*611 during the preoperational (l967*l973) ar.d postoperational (1974) periods in Conovin~o Pond.

601 602 603 604 605 606 607 608 609 610 611 Weighted

&an 1967 i) 1.75 1.'5 1.53 1.74 1.67 1.70 2.0I+

1.so 1.80 o.s1 0.4S 0.44 0.46 0,47 o.Sl o.61 0.43 o.42 1968 ii 2,56 2.43 2.49 2.n 2.30 1.93 2.28 l,63 t.97 1.87 2.10 2,40 0,67 o.n 0.67 0,6S 0.62 0,56 o.64-0.47 0.62 0.66 0.10 o.53 1969 i) 2.15 1.92 l.4S 2.00 1.89 2.11 1.26 1.79 2,26 2.3S g

0.68 0.61 0.46 O.Sl 0,48 0.68 0,42 o *.54 o.ao 0 *.53 1970 i>

1.92 1.70 1.64 1.04 2.48 1 *.52 1.99 1.45 1.9S 1.82 t.27 1.77 o.ss 0.49 o *.58 o.31 0,72 0,48 o.54 0.44 o.sG 0.57 o.4s 0.42 1971

'D 1.68 1.76 1,48 2.06 1,82 1.27 1,89 1.77.

2.os 1.64 1.42 1,82 E

0.47 0,63 0,49 0,60 o.ss 0.42 o *.s1 0.56 0.79 0.79 o.ss o.42 197l ii 2.sa 2.29 2.22 2.20 2.29 2.43 2.57 2.33 2.44 2.39 t.69 2.10 g

0.10 0,60 0,62 0,58 0,64 0,70 0,66 0.74 0.64 0.72 0.49 0.42 1973 ii 1.86 2.00 2.23 2.so 1.,91 2.21 2.54 2.12 2,08 2.os 1,70 2.JS E

0,4.5 o.s6 o.se o.ss 0.55 0 *.55 0.60 o *.Y+

0.60 0.57 0.54 o.45 1974 ii 2.01 2.00 1.95 2.08 1.93 2.00 2.52 2,36 2.16 2.24 1.73 2,45 II 0.46 o.i.6 o.so 0.47 0.41 0.54 0,S9 0,59 o.54 0.6S o.sz 0.46 D* -l;l Pi lo&z P1 pi

• p~opoi:tiOll 0£ J. th tu:on by llUlllbcr I* _t> __

log2 S S

• No. 0£ tu:a t

t

.t f

\\

7.1-53 i

i. ". t i;..

l i*

t I r !"

I:

~ i r,*

~.;

1967 1968 1969 1970 1971 1972 1973 1974 TA9LE 7.l.~-5 Monthly species diversity (0) and equitability (E) indices for benthic organisl!IS collected during the preoperational (1967*1973) and postoperation.al (1974) periods io Coo°"'1ngo rood.

Jan Feb Kar Apr May Jun

.rul Aug Sep Oct ND'I Dec D

0,98 1.44 l.7S 1.96 2.03 2.23 2.3S B

0.21 0.45 0.47 o.ss 0.64 0.64 0.68 D

2.80 2.S4 l.6S 1.45 1.76 2.06 1.80 B

o.76 0.69 0,43 0.46 0.51 o.65 0.60 ii 1,35 1.29 1.45 2.16 2 *.57 2.63 2.92 B

o.41 o.34 o.42 o.sa 0.11 0.76 0.11 i) 2,38 2.41 1.. 83 1.39 1.49 1.43 1,84 2.00 B

o.92 0.73 0,48 0,36 o.42 o.s5 o.s5 0.63 D

2.00 0,98 1.66 1,78 l.3S 2,22 2,19 B

o.s1 0,31 0,5S O,Sl o,,8 0.19 0.73 ii 2,37 1.94 1.42 1.06 1.60 2.2.5 2,06 2.18 1.79 2.19 B

0.71 o.ss 0.43 0.35 o.s1 o.s2 0,59 o.63 o.47 0,63

'D 2.23 2.49 2.04 1.98 1.90 1.90 1.66 1.91 2.3S 2.42 2.44 2.18 B

o.64 0.78 0,59 a.so o.49 0.48 0,46 0.49 0.62 o.68 o.6s 0.66 j) 1.88 1.64 1.52 1.39 1.37 1.37 1,42 1.37 1.72 1.84 1,76 B

0.48 o.36 0.34 0.32 0,33 0.33 0.38 0.33 0,42 0.43 0.43 i* *F.iPs. log2 pi p1

• proportion of tth taxon by 1111111ber 1

• o ios2 s S

• 1100 of tax.a

\\

,.. r*

~

• f '.

7.1-54 lleighted.

Kean 1.80 0.42 2.40 O.SJ -----

2.35 0.53 1.77 o.42 1.82 0.42 2.10 0.42 2.35 0.45

~

2,43 0.46

• • .-1

• • I I

• .:. y TA3L-C: 7.1.5-o l -*t lion 1W1R"4r (per 81 in.2 ) ol th* oelected repreuntattve *P"du of benthtc organi1111a at Station 601-611 during t

J preopcru1on&l (1967-1973) and po1toperatlonal (1974) pedoda io. C""""illSO Poo.d, Dulles indicate aam?ling ut cO'Clducted,

. t 1

SCatiO'CI 601 602 603 604 60S 606 607 608 609 610 611 Kean

• 1

~

Tua

'Taa\\'

• . i Ptoehdius ap.

1367 1.70 2,40 1.27 1.45 2.36 1.82 0.33 0.89 1.S6

• • 1.

(cc-.plex) 1968 3.42 7.12 1.80 4.30 4.11 4.22 2.66 2.1s 4,62 2.14 0.66 3.SJ

i}

1969 6.00 8.90 3,44 4.62 7.11 18.21 8,00 6.00 3.25 8.ZS 1970 1.61 4.SO 1.06 0.89 s.os

3. 74 z.aa 2.JS 4.44 6.0&

2.00 l.18 1971 1 *.38 2.00 1.46 2.ll 1.08 1.31 1.61 1.54 3,23 1.9?

1.46 1.7'

~

1972 S.43 4.48 2.19 4.0S 6.09 6,67 8.86 1.81

!i.00 8.67 7.29 S.44

• 't 1973 25.45 6.45 6.00 16.50

.s.so S.27 15.09 19.32 17.36

%3.82 23.7l 14.95

'1 1974 59.67 22.94 29,59 44.78 S,96 10.69 28.79 29.65 26.73 24.98 20,57 27.41 Llmnodritus 1967 12.00 21.20 11.54 17.45 19.S4 20,36 7.89 19.00 16.45 ho ff111d s :o ri 1968

9. 7S 19.lS S.90 16, 10 15.78 lS,33 9.00

18. J7 26.87 13.12 24.17 14.86 1969 16.75 2s.20 36.SS 32.00 40.U 21,43 42.25 29.71 1:..62 2G.85

.1 1970 13.56 29.28 9.S9

32. 7&

14. ll 28.SJ 21.65 34,12 20.83 23.25 44.S~

24. 72 1971 17.08 14.31 14.54 11.69 21.ll 24,15 12.85 16.61 13.92 14.lS 24.00 l~. 99

• t 1972 4.57 S.66 4.29 6.67 10.50 6.48 9.57 7,.ll 3.l9 7.90 17.57 8.00 1973 4.36 4.41

s. 7.l S.90 16.S6 S,86 6.73 3.86 4.00 6.CO 21.SJ 1.;:.

1974 39,93 26.27 40.57 29.82 l6,17 23.18 31, 19 ia.so 21.89 9.04 32.94 29.~B

• • 1

. ' *1 Cheoboru1 1967 o.so 0.30 0.27 0.4S 0.64 0.45 1.11 0.89 o.56

J punc:cipeMil 1968 4.00 1.00 2.00 6,SO 2.00 1.44 l.SS 0,50 10.25 30.29 16.83 5.97 1969 0,25 z.20 1.22 1.75 0.89 0.57 2.00

),00 9.37 2.:S

. *1 1970 0.39 l.06 0.18 0.11 l.68 1,37 0.20 1.24 o.67 4.Ja 2.78 1.%4 1971 1.92 0.15 1.00 3.69 17.0S l,46 2.46 5.46 5.85 11.69 6.31 5.U.

I I

1972 1.62 0.62 1.86 C.95

.5.33 0.86 2.90 2.05 1.43 5.43 4.76 2.51

" * ~

1973 0.32 0.14 0.14 1.41 0.82 0.04 l.SO 1.63 2.12 10.04 10. 77 Z.63 I

1974 0.52 O.lS 1.42 2.65 0.11 0.34 1.62 10.00 6.16 13.39 13.24 11.45

'i

• ~;~

J!uagent11 1967 o.oo o.oo o.oo o.oo o.oo 0,00 o.oo 0.11 0.01 ll!!?.!S.!.

U68 o.oo 0.00 o.oo o.oo 1.11 o.oo 0.00 0.00 0.00 0.00 0.00 0.1.'.l 1969 o.oo 0.10 o.oo 2.87 0.11 0.07 o.oo 0.00 0.00 0.00 0,)')

1970 o.oo 0,06 0.00 0.22 1.63 o.oo O.lS o.oo 0.06 o.oo o.oo 0.20 1971 0.00 o.oo

~.23 O.l1 0.16 0.08 o.oo 0.08 0.00 o.oo 0.0()

0.08 1972 o.oo o.oa o.oo 0.14 0.14 o.oo o.oo o.oo o.oo 0.00 0.00 o.~J 1973 o.oo o.oo o.oo 0.04 0.00 o.oo 0.04 o.oo o.oo o.oo o.oo 0.01 1974 o.os o.os o.oo 0.20 o.oo o.oo o.oo o.oo o.oo o.oo o.oo O.OJ J

~.

l

.: f J

• t 4

• • 1 7.1-55

• I

• t

a;m WMi&&n¥nw1w;aw

.~ '

I' t';>'

l

~..

~

I' *,

f'.

I f:

\\

I:*;*.

f f

ir* I

~*.

• r.,

t:

}'

~-

r*:.

~~.*

~{.*;

1968 1970 1971 1972 1973 1968 1970 1971 1972 1973 1968 1970 1971 TABLE 7.1.5-7 Spearman rank correlation (r5 ) test on densities of common taxa at Stations 601-611 between years in Conowingo Pond.

1970 1971 1972 1973 Limnodrilus hoffmeisteri 0.61 0.04 0.41

-0.17 o.os 0.33 0.11

~ ~--* --- --*- ~-~--

~~--

0.02 0.22 0.59*

Chaoborus punctipennis 0.20 0.56*

0.41 o.61*

0.57*

o.so 0.37

o. 75*"k 0.76**

0.62*

Procladius sp. (complex) 0.24 0.36

-0.31

-P.32 0.03 0.44

-0.15

-0.19 0.28 1974

-0.43

-0.50 0.25

-0.18 0.27 0.54*

0.20 0.45 o.42 0.87**

-o.os

-0.68*

0.37 1972

__ 0.10

_ -0.. 47 1973 Significant at 95% level, rs (0.05, 11) = 0.54

• • Significant at 99% level, rs (O.Ol, 11) = 0.73 7.1-56 o.so

~ ~-~

TA;,LE 7. l.5-8 lndel& of peccent 1imJ.lacit1 of 1pecie1 compo1itlon bet~en ye*~* et Station* 60l-6ll ducia.g pceoperetlo11&l (1967-1973) and pootoper*t1oDAl (1974) period* in Conowiago loud, 68 1968 66 76 72 1969 79 86 78 66 81 1970 76 72

• SJ 82 74 69 72 1971 78 81 BS 87 42 47 50 54 J9 1972 40 57 57 Sl 45 59 21 3S 39 36 29 1973 31 46 44 41 34 86

"""'6~2.__~8~0.....,~46:;.-...,....,,~54:---:-='6~0'--:-="5~7__,:-=-'4~7-1974...,._,~44,,,_..,..,~58:--..,,..,,;5~7,...-.,.,,::5~4'--,,..,,.C4~6~,,.,,.;8~5,.._.==:8;:;.J 1973 1972 1971 1970 19&9 1968 1967 1967 1968 1969 1970 1971 1972 1973 76 77

.53 S4 Sl 58 S4 1974 SJ S7 49 57 SO

• 75 68 51 54 50 56 48 1973 40 46 32 44 SS 43 39 37 54 39 1972 JS 41 32 42 BO 8~

70 89 1971 76 83 6S 92 71 7S 1970 82 56 70 76 1969 68 1968 70 80 1968 8S 86 90 1969 89 90 16 a2 73 1970 84 as 88 68 67 70 65 1971 79 79 78 86 70 71 58 66 SS 1972 50 58 51 51 45 70 52 70 71 74 70 1973 40 50 46 47 38 19

.,,._.8~8--..,...,.-'6~4~,...,-,5~1~-'"67..._..,...,..7_~~.,..-7~4~~7~5-11974....,._~5~1~_.,61-=-_.,....5~7~----'5~8~---49 1973 1972 1971 1970 1959 1968 1967 1967 196~ 1969 1970 1971 82 87 1972 l97J 84 77 54 61 63 56 51 1974 47 52 47 47 59 GO 73 73 43 54 82 50 46 1973 31 36 34 33 34 48 SS SS 77 52 48 1972 53 58 60 59 65 as 5s 64 87 1971 so 81 11 ao 61 66 86 1970 87 87 06 51 Sl 1969 80 84 67 1968 90 1968 87 1969 68 81 71 1970 52 62 77 82 90 1971 79 71 73 66 66 60 59 1972 56 63 64 63 61 38 40 38 36 1973 46 47 47 47 76

.,,.,,..;7~5..._,='=76~.,,..,..,6~1.....,,..,.,,6s~..,..,...6~9..._,,.-',s9,,_...,..,,..,...,-,1914....,.....,...__,_S~4..,..,...-"'5_9__,,~s~J'----"s_2~~'~a......,~s~5.,...

19:: 19::

19;~

19;~ 1?59 19:~ 1967 197411967 1966 1%9 1970 1971 1973 1973 17 62 47 59 1973 80 69 64 1972 80 70 1971 63 1970 1969 1968 7.1-57

(.

' \\* k.

TA%E 7.1.5-9 Com;l*ri1011 of the monthly llH!8D blom&.11 (mg dry '<eight) per 81 iu.2 at Stations during preoperation&l (1967-1973) and po1toperatioaal (1974) periods ill c.mo..r.t.ngo Plmd..Dashe1.iJuiicate 1.ampllng not c:onducted.

Ko11tla Ja11 Feb Har A;lr May Jun Jiil Aug Sep Oct Nov Dec:

te*r 1967 U.890 U *.509 12.693 12.994 9,002 10.753 16.164 1968 10.S79 8.687 6.782 14.609 6_.828 14.814 15.060 1969 27.-488 23.054 14.099 32.256 15.605 34.752 43.016 1970 39.472 9,239 16.672 23.172 10.811 9.118 15.097 10.823 1971 37.201 18.285 14.988 12.6Z6 8.483 l0.148 8.352 1972 10.590 10.155 11.080 11.254 B.645 2.831 5.689 7.333

12. 922 9.105 1973 14.732 13.002 12.700 9.049 5.478 3.192 s.210 3.841 6.614 12.871 13.685 15. lll 1974 U.895 15.611 19.106 U.809 21.154 U.976 14.646 17.388 22.451 32.209 40.024 7.1-58

i 1

• 11

i 25

<(

x 20

~

~15 a::

~ 10

~

z 5

r=-o.oga o...,.,.~!'"""'""--~~~--~~----~--~--~--~----"~~

1.0 1A 18 2.2 2.6 20

<! x

~15 lJ..

0 e:: w

~10

> z 5

3.0 SPECIES DIVERSITY r:-n5os Q.__-----;:!----~~~--~~----L----~..1.-------

.2

.4

.6

.s 1.0 EOUITABILITY FIGURE 7, 1,5-1 Plot of nU1t1ber of taxa (species richness) and species diversity (upper) and equitability (lower) indices for benthic organisms in Conowingo Pond, 1967-1974.

7.1-59

~-

MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE POND

_ --MUDDY-CREEK PEACH BOTTOM ATOMIC POWER STATION STONEWALL POIN.T STATE LINE-P_A_. -----

MG.

RELATIVE DENSITY PER 81-in. 2- -~

• < o. 24

• 0.25 - 4.99 s.oo - 9.99 e 10.oo - 19,99 9 > 20.00 FIGURE 7.1.5-2 PEACH BOTTOM BEACH WILLIAMS TUNNEL GLEN COVE Relative densities of Procladius sp. at various stations in Conowingo* Pond, 1967-1974.

7.1-60

' i. l MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE PONO MUDDY CREEK PEACH BOTTOM ATOMIC POWER STATION STONEWALL POINT STATE LINE-P_A_. -----

MD.

RELATIVE DENSITY PER 81 in. 2

• < 0.24 0.25 - 4.99 5.00 - 9.99 ro.oo - 19.99

> 20.00 FIGURR 7.1.)-3 PEACH BOTTOM BEACH WILLIAMS TUNNEL GLEN COVE Relative densities of Limnodrilus hoffmeisteri at various stations in Conowingo Pond, 1967-1974.

7. 1-61

I

\\,.*.

~*. (

~'.

1.:.

~,*. !

k:)

l.. i

r.,.

l. " ~

~* ~ *~,

~,..

~..

MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE PONO MUDDY CREEK PEACH BOTTOM ATOMIC POWER STATION STONEWALL POINT STATE LINE..;..P_A. ____

MD

• RELATIVE DENSITY PER 81 in. ~---

• < 0.24

• 0.25 - 4.99 5.00 - 9.99 o.oo - 19.99 fj> 20.00 FIGURE 7.1.5-4 PEACH BOTTOM BEACH WILLIAMS TUNNEL WILDCAT TUNNEL GLEN COVE Relative densites of Chaoborus punctipennis at various stations in Conowingo Pond, 1967-1974.

7.l-62

• I 1

~.

~.

• J l

J

j

• .. ~

• ~

. 1*

\\

• 1

-:~

..r MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE PONO MUDDY CREEK PEACH BOTTOM ATOMIC POWER STATION STONEWALL POINT STATE LINE.;..P_A.;...,_ ___

RELATIVE DENSITY PER 81 in.2 MO.

e O.Ol-0.24

! 0.25 - 4.99 v s.oo - 9.99 91.o.oo - 19.99 t)> 20.00 FIGURE 7.1.5-5 PEACH BOTTOM BEACH WILLIAMS TUNNEL GLEN COVE Relative densities of Hexagenia limbata at various stations in Conowingo Pond, 1967-1974.

7.1-63

't-

~~.-~.. i

~*~:, *

~! ::... ; lrj

.{:J:*?~:.1

,~'.~* -- *

~ *.

~.

~.

' '* \\.

t j.

!

• i

} "

7.2.0 ABUNDANCE AND DISTRIBUTION OF FISHES

7. 2. 1 INTRODUCTiotl The study of fishes in conowingo Pond is based on over 12,000 collections made by meter net, trap net, trawl and seine from 1966 to 1971t.

Monitoring stations for each gear were located on the basis of available habitats, physical constraints imposed by topography and the location of the Station.

Stations were located upstream and downstream from PBAPS and in areas expected to be within the heated plume.

Twelve Trap Net Stations (Figure 7.2.1-1), 18 Trawl Zone stations (Figure 7.2.1-2),

13 Trawl Transects Stations (Figure 7.2.1-3),

12 Seine Stations (Figure 7.2.1-4) and 13 Plankton Meter Net Stations (Figure 7.2.1-5) are sampled.

collections are made twice a month.

When PBAES Unit No. 2 operated-at 100%

power consistently,~in July

1974, an additional nine trawl stations and eight trap net stations were established inside and outside of the thermal plume (Figures 7.2.3-1 and 7.2.3-2).

Trawl samples were taken three times a

week and trap net Stations were sampled twice a month.

samples were replicated.

The abundance and distribution of fishes at the various stations has been well documented (see section 3 in Robbins and Mather, 1974a, b; 1975a, b).

Comparisons between the catch of fishes in the pre-and postoperational periods are also giv~n in the above reports.

A summary of these findings is given below

• It is impractical to delineate the abundance of fishes on the basis of a 2 c (3.6 F) isotherm because the plume will vary in size with season and perhaps within a day.

7.2.2 SPECIES COMPOSITION t

The fishes in the Pond are, for the most

part, i

classified as warm water fishes.

Some 56 species were taken in t

the Pond and the tributary streams from 1966 through 1974 (Tabl~

f 7.2.2-1).

The spotfin shiner, bluegill, pumpkinseed, bluntnose l.

• minnow and spottail shiner are the common forage fishes.

The

j.

white crappie and channel catfish are the most important pan 1

fishes.

The game fishes such as the smallmouth bass, largemouth t

bass, yellow perch and walleye are uncommon.

No rare or J.

endangered, commercially harvested or migratory anadromous fishes 1*

are present in the Pond.

The relative abundance differs as

-~~*- -*----- measured~by a --given sampling gear but the domir.ant--species -ar- ---

. t

• the white crappie, channel catfish, pumpkinseed, bluegill and spotfin shiner (Table 7. 2. 2-2).

i

) _

1

• • .1 j

j

.i

.~...

..;L:._

The alewife, American shad, blueback herring and striped bass were introduced at various times in the last 10 years, but none were taken in the Pond in the present study.

Although the 7.2-1

walleye was stocked by the State of Maryland, it is relatively

• ~-

uncommon.

The Pennsylvania Fish Commission has stocked muskellunge upstream in the vicinity of Falmouth, Pennsylvania and a few adult muskellunge are taken in the Pond.

The gizzard shad was inadvertently introduced in 1972 from below conowingo Dam (during the American shad study).

Young gizzard shad were taken in conowingo Pond in 1972 and in subsequent years and may be considered as being established.

The white perch also was introduced.

several adults were taken in 1974.

The extent to which the white perch may become established remains to be seen.

7.2.2.1 Distribution The five common species (white crappie, channel catfish, pumpkinseed, bluegill and spotfin shiner) are widely distributed in the Pond.

The distribution of many of the less common fishes, such as the walleye, smallmouth bass, largemouth bass and many cyprinids including the bluntnose minnow, is more limited.

The largemouth bass is more common in the southern part of the Pond whereas the smallmouth bass, walleye and bluntnose minnow are found near the northern part, primarily between Holtwood Dam and the Muddy Run Station.

The depth and temporal distribution of larval fishes were statistically analyzed using a 2 x 2 factorial analysis of variance.

Larvae of channel catfish and tessellated darter were found primarily at the bottom both in day and night.

Those of carp and quillback were concentrated near the bottom in the day and at the surface at night.

Larvae of the bluegill larger than 13 mm appeared to remain near the bottom.

Larvae of the bluegill and other ~~BQID~~ (~ 13 mm) were most abundant at the surface both in the day and night.

Larvae of channel catfish and ~§QQIDis were found mainly near shore, while those of carp, quillback and tessellated darter were distributed throughout the Pond

• 7.2.2.2 Abundance some 48 fishes were collected by seine The common species in order of decreasing spotfin shiner, bluegill and bluntnose minnow seasonal fluctuations in abundance occur.

diversity ranged from 1.12 (1970) to 2.79 composition was similar at most stations.

(Table 7.2.2-3).

abundance are the but annual and Annual species (1969).

Species In trap nets, 43 species were caught.

The most conunon in order of decreasing abundance are the white crappie, channel catfish, bluegill and pumpkinseed (Table 7.2.2-4).

Game fishes such as the smallmouth bass, largemouth bass and walleye are uncommon.

Fluctuations were observed between years and months in catch per effort of the common species.

Much of this variation was associated with differences in year class strength.

7.2-2

l l i I

.

• t.

! l *

f.

i

)

1

\\

l l

~

Abundance of most species was low in 1972, the year of Tropical Storm Agnes.

One exception was the catch of the carp which increased substantially in 1972.

Some 31 species were taken in Trawl Zone 405 (off PBAPS) and 32 species were taken in Trawl Zone 408 (off Peters Creek)

(Tables 7.2.2-5 and 7.2.2-6).

The most common fish in Zone 408 was the white crappie and in Zone 405 it was the channel catfish.

The third and fourth most common fishes in both zones were the bluegill and pumpkinseed.

Both seasonal and annual fluctuations in abundance were noted.

More young channel catfish were taken in zone 405 while more young white crappie were taken in Zone 408.

A considerable decrease in catch per effort of fishes was noted in July 1972 following Tropical storm Agnes.

Of the 34 fishes taken at Trawl Transect Stations, the common species in_ord~r o.L_decreasing abundance are the channel catfish, white crappie, bluegill, pumpkinseed, tessellated darter and spottail shiner (Table 7.2.2-7).

Their abundance varies between years and stations.

The white crappie, pumpkinseed and bluegill are most abundant along the east shore.

The channel catfish is more abundant along the west shore between an area just north of the station south to Michael Run and along the east shore off Fishing Creek and Wildcat Tunnel.

No consistent trends are evident in the distribution of the spottail shiner and tessellated darter.

Some 30. fishes were collected by meter net (Table 7.2.2-8).

The larvae of tessellated darter, quillback,

carp, channel catfish and bluegill were the most common.

Together they comprised about 90% of all larvae collected.

Yearly fluctuations occurred in the abundance of these larvae.

Except for the great abundance of the larvae of quillback; other species were scarce in 1972.

The decrease in abundance of larvae of other species was due to the catostrophic flooding caused by Tropical storm Agnes in June 1972 *

---

*~---------- ----*----

7.2-3

l I

I i i i

I

\\

I I l

{

l

• j l I I I

j.

TA%P. 7.2.i?*l Llst of scientific and c0tm1on names of fishes collected in Conowingo Pond and tributary streams.

(,\\ccord.l.na to Balley, et al.

1970).

Scientific Name Family - Amiidae Amia calva Family - Clupeidae Dorosoma cepedianwa Family - Salmonidae Sa lmo galrdneri Satmo trutta satVOl~ontlnalis Family - esocidae

~

niger Esox lucius E:;ox ;MSqU[nongy ram.I.Ly - Cyprlnidae Carnpostoma anomalum carassius auracus Cl.I.nos tomu;-ftmdU to ides c;;rtn~.;rp lo Rxoglossum maxlllinsua Nocomls micropogon Notcmtgonus crysoleuca*

Notropis ~

Notropis analostanus Notroph cornutus Notropls hudson.l.us Notropis procne Notropis rubellus Notropis rulopterus Pimephalcs ~

Pimephales promnlas Rhinichthys !tratulus Rhinichthys £!'£.&.!.!£!!!

Semotilus atromaculatus Semotilus corporal.I.*

Ericymb11 buccata Common llame Bow fins llowfin Herrings Cfazard >1had Trouts Rainbow trout llro.. m trout Brook trout Pikes Chain pickerel Hortltern pike Muskellunge Minnows and carps Stoncroller Goldfish Rosyside dace Carp Cutlips minnow River chub Golden shiner Comely shiner Satinfin shiner C011111on shiner Spottall shiner Swallowtail shiner Rosyface shin"r Spotfin shiner Bluntnose minnow Fathead minnow alacknose dace Longnosc dace Creek chub Fall fish Silvcrjaw minnow Scienti fie Nrunc Family - catostomidae Carpiodas £YP,!'inu>1 Catostomus co11111crsoni

[~.!.mY!.O!l oblongus

!!)rp~ntclium nigricans Moxostoma macrolepidotum Family - lctaluridae Ictalurus catus rctalurus ilatS'fis le talil'rUs° nebulOSus

!~9 punctatu~

~

insignh Family - Anguillidae

~gull!,!~

Family - Cyprinodontidae

.[,undulus diaphanus Fundutus hetcroclltus Family - Percichthyidae

~

amcricana Family - Centrarchidae

~blop!.1.!=es rupcstrls Lepomis aurttus

!.!J!~ cyanellus Lepomis gibbosus Lepomis macrochirus Micropterus dolomieui Micropterus salmoides Pomoxis annuLaris Pomods nig~latus F.'llllily - Pc rcidae Etheostoma olmstedi Etheostoma zonate Perea flave~

Percina canrodes Perclna peltata Stizostedlon ~

Common Name Suckers Qui llback

}n1lte sucker Creek chubsucker Northern hog sucker Shorthead redhorse Freshwater catfishes Whito catfish Yellow bullhead Brown bullhead Channel catfish Margined madtom 1.'reshwater ce ls American eel Killiflshes Banded ki llifish MW1D11ichog Temperate basses White perch Sunfishes Rock. bass Redbreast sunfish Green sun fish Pumpkinseed Bluegill Sma llmout h bass largemouth bass White crappie lllack crappie Perches Tessellated darter

!landed darter Yellow perch Logperch Shield darter Walleye

Catch per effort for ff.shes collected by vutoua gears in Conowingo Pond, 1966*1974.

Trawl Zone Trawl Zone Trawl Transect Trap Net Seine Meter Net Station 405 408 No. Collec_tions 1209 1167 1499 2893 1567 2961 tlo, Species 31 33 34 43 48 31 Species A, £.!E!

!. rostrata 0.05

o. ce2edianum 0.01 0,50 0.01 0,05 0.08

~. gairdneri

s. ~

S, fonttnalis i

• niser E, lucius

!. tn:uquinongy 0.01

£. anomalum 0.08

g. auratus ii

g. ~ides 0,04

• . (

g. carpio 1,02 1,28 0,96 l.30 0.04 J,50

~* buccata E, m;;;(iffin gua O,OJ

i. tnicrol!oson 0,08

f!. cr:i:soleucas 0,04 0,16 0,05 0,38 0.17 0.01

• ~. *~;

N, am.oenus 0.01 0.49

g. ~anus

~. carnutus 0,25

~* hudsanius 1,13 2.43 1,64 0.02 1,49 0.02 N, procne

• .Ir 0, 18 L>'

N. rubellus 0, 12

~. al!ila2terua 0,01 0,04 0.02 0.04 56,lt 0.11

'P. natatus 0,01 0,08 0.02 2,50

'P. promelas 0,01 it. atratulus 0,84

!. cataractae Q,06

~. *\\

~. atromacu Latus 0,26

,::'.~;

!* cor2oralis 0,02

c. cl'.l!rinus 0.01 0,03 0,02 0.02 1.50 5,46

~~ '

c, cotnme rsonl 0.01 0,03 0.02 0.14 0.23 0,04

e. oblon!ll!s ji. nigricons o.14

. ~:.

!:!* macroleJ!1dotwa 0,01 0.01 0.01 0,04 0.02 I, catus 0,04 0,02 0,06 0.22 0.01

!. natali.s 0,01 0,62 0,01 0.01 I, nabulo!lus 0,31 0,68 0,49 1,61 0.01 i*1*

1. punctatus 38,63 28,94 45.42 7,28 o.oa 2.10 I'.

E. insi&nis i::.

f.* dtaehanus 0.01 l

F, \\ietcroclitus 0.02

~. ru2astr1s 1t 0.20 0,01 0,01 f ~

1* auritus 0,28 0,07 0.01

.! *~:*

L, c~anellus 0.01 0.02

):.-

r. sibbosus l.13 3,39 1,15 2.46 1,93 0.14

.~ :'-

L. macrachi rus 2.18 8,88 4,01 3.79 7,66 0.82 i...

~~

LCJ!omis spp,_.

-~~---*

-* --.-~

.. -~

. 0,.9S,

!.1* datointeui 0.02 0.08 0,03 O,Ol 0,29 0.02

'... ~

~. aalmoides 0.01 0.08 0,01 0.02 0,87 fr

\\;,

f* annularis 21.42 46.91 23, 14 55.73 0,69 0,61 P, nisromacu la tus O,Ol 0.03 0.02 0.12 0.01

.~.'";

E. olmstedi l,62 1,56 l.66 1,90 8,64

g. zonale 0.01

~ccns I~.'

f*

0.02 0,12 0.07 0,06 0.02 r*

f* caj!rodes 0.01 0.02

~ ~ *~;

l* peltata o.u

§.. ~

0.03 0.02 0.02 0.03 0.09 0,03

~l

i...

1....

Total

67. 72 95,34 78.48 74.53 78,57 22.n

~ -i~

t...,

• Less than O.Ol i: £

~>

u

,,.. ;1 r:~.

• 7.2-6 lif i11 t*i*

~

TABLE 7,?.1!-}

Catch per effort of fishes (number per collection) collected by 10- and ts x 4 L.

the preoperational (1966-1973) a1td postoperational (1974) periods in Con0To1tngo I

Year 1966 1967 1968 1969 1970 1971 1972 1973 1974" No. Collections 67 82 115 124 177 2t,5 256 236

'l6S No. Sped.cs 30 26 34 28 33 38

'.19 34 37 Spectes

s. true ta 0.01

1. fonttn.a lt s 0.01

.... *.:.~~A

£. an011U1 lwn 0.01 o.os 0.94 0,03 0,06 0.23 0,02 o.os 0.02

c. funduloides 0.01 0.01 0.21 0.08 0.04 o.oa 0.01 o.o:t

c. carp to 0.15 o.os 0,04 0.11 0.03 0.02

'E. buccaca O,Ol I

g, rnnl<Lllin!!!!_

O.O'.l 0.01 0.01 0.02 0,06 0.02 o.os J:!. mtcropogon 0.03 0.01 0.21

o. Q4.

o.oa 0.09 0.22 N. crl:'.sol.,ucas 0.31 0.24 1.62

.0.10 0.26 0, 16 0, 18 0,06 0.06

'N. amoenus 0,76 O,ZJ Z.94 0.39 0.73 o.* 16 0.59 0,55 0.39 I

i1. analostanus 0.01

'N. cornutus 0.04 0.07 l.38 0.02 0.14 0,31 0,26 0, 17 0,49

~. hudsonlas 3.18 0,56 6.24 2,93 1.29 2.45 1.30 0.18 l.12 ii. procno 0.42 0,05 0,64 0,08 0.12 0.01 0.12 0.26 0,37 N, rubellu8 0.09 o.35 0,09 0.12 0.16 0,05 0.14 0.14 1!. seiloeter:us 109.90 53.21 140,97 32,82 64,37 51.12 31,87 68,96 72.BS f* notatus 18.52 1.32 4..18 2,98 1.94 1.52 0.83 1,22 3.20

~:~%7~?:!':.'.~ :.

P. e-co~las 0.01 0.01 0.04 0.01 0.02

~. <1tratulu1 0.01 0.04 0,35 0,28 0.35 2,0) 1.90

o. 77 o.~'-~/~r. ~..,.**:

~- cataractae 0.01 0.04 0.10 o.14 0.11 a.OJ g:~: ):(::.< *"

s. atromaculatus 0.41 0.06 O,S9 0.41 O. ll 0.42

~. carporalh 0, l2 0.02 0,04 0.06 0.01 O.OZ._;._ ~.:

t

£* cypri.nus 0.16 o.os 0,56 3.27 0.39 1.28 0.16 2.20 3.64 L.!io***

• t

c. comntersoni 0.01 0,15 o.oa 0.64 o.os 0.06 0.61 0.23.

j!, nigticans 0,03 0,23 0,04 0.11 0.10 0,02 0.46 0.14 tl* macrolepidotwn 0.01 o.os O.OJ o.os o.o:t I. catu1 0.01

t. natalts 0,0J 0,03 0.01

!. nebulosu&

0.07 0,06 0.09 0.01 0.01 f* punctatus 0.46 0.41 0.12 0.02 0.01 0,09 0.01 0.01 0.01 0,08

.!!* instgn18

!* diaphanus 0,03 0.01 O,Ol 0,02 0,01 F. heteroclitus O.OJ 0,09 0.02 0,03 0.01 0.01 0,02

~- rupesttis 0.01 o.os O.OJ 0.01 0.01 O,Ol 0,01 L. auritus 0.01 0.11 0,38 0,15 0.11 0.04 o.os 0.06 0.06 0,07

};, cyanellus 0.01 0.06 0.01 0.01 1* gibbosua 12.64 0,76 22.35 2.79

o. 73 t.75 0.44 0,55 0.77 l.93 L, macrochi r:us 55.45 7.18 101,65 8,53 1,24 8.19 1,89 1,44 0,52 7.66 tl* do lomieu 1 O.lS 0,33 0.44 1.81 0.16 0.08 0,03 0,06 0,42 0.29 M, salmoides 0,31 0.58 l.82 3,00 0,28 1.25 0.12 0.55 1.32 0,87 "P. annularls 5.40 0.28 1,32 0,98 0, 12 1,22 0,69 0,04 0,08 0.69

~. nigrornacutatus 0.10 0,01 0.02 0.01 0.01 O,Ol E. o lmstedi 0.67 1,34 2,82 3,59 0,91 2.02 0,58 0,56 5.05 l,90 E. zonale 0.01 0.02 0.01 P. flavescens 0.01 f* caprodes 0,01 0,04 0.04 0.01 0.01 0,03 o.oz

!* peltata 0,03 0,02 2* vitreum 0,03 o.ao 0.01 0,09 Total 208,86 67.JS 292,35 64.01

74. 56 74,10 42,46 79.54 93.33 78.57

• Lesa than 0,01 7.2-7

TABLF. 1,?,?-4 Catch por effort (number por 21+-hr) for fishes collected by 3 x 6 ft tr;ip net at rrap Net Stations during preopcratl<>nal (1966-1973) and postoperationa1 (1971+) periods in Conovinso Pond.

Year 1966 No. Colloctiona 38 No, Species 21 No, Hour a 992 Ila. Trap D.a.ys l+l,33 Species

,\\. calva

'.;

?-* ~--* --~ --* ~~-;-roitrat...---~

- ~-

- 0,65

_!!, cepedla1\\WD

.(*.

§.. gairdoncri

!* trutta

!*~i\\li11 r;.:*

E, niset'

'i..*'

i,. lucius Ut

!* WQuTnongy

• ~: *.

C, aura.tus

c. fUruiULOldco l('

£, carplO-

• • .':~~

!i* rdcropogon

~** *~.

N. c rxso leucas

!~~.-.. :_*.

°E* amacnus

!i* ~ua N. pracne iJ:, rubal lu*

J:i. spTIO'iite'rus

!'.* notatus

£, cvprlous

c. conmer!ont ii. 1tigricans tl. macro lepida tum 1* c;atus l* natal ii 1, nebulaBl\\t I* 2unc.Eatui11

u. inslgnh

!. l\\cteracl lt1a L:*

ft

~!:

~.:

f!* *:

~- ru2cstria

!:* au rt tu a L. cxanellus

!;. gibbasus

!:* macroch l rua tl* dolomieui

!:!* salmaldc>s

!* annula~l*

P, ntsrOG1aculatus

§. olmstedl.

!'.* ~ns

!'.* ca2rades

!* !lli!l!!!!

0.16 1,25 0,02 a.o4 a.oz o.a9 0,02 a.oi.

a.J l 0,31 0.36 8,73 Q,38 a,Ol 1.50 l.38 0,07 112.84 0,31 0,02 1967 1968 l969 207 235 26~

24 21 23 4416 6067 6206 181..00 252. 79 258,58

- 0.01 a.OJ o.07 0.01 0,01 0.08 0.18 O.J5 0.23 0, 16 0,62 a.Ol 0.16 0.01 0.12 0,01 0.01 0,02 0.11 0,16 0,13 0.01 0.07 a.07 0.03 U,51 0.11 0,31t 0.21 0,09 1.22 1.27 1.15 2,18 10,83 2.43 17.72 0.45 0.22 0.40 a.16 a, 14 0.54 0.01 0.06 2.95 1.42 3,87 1,34 2.61 6,75 0.01 a.OJ o.a3 S0,39 33,35 73.64 0,04 a,05 0,06 a.01 o.0t1 o.oa 0,13 a.03 0,04 1970 1971 l972 1973 1974 Total 304 346 533 1+59 S07 2d93 26 25 27 35 39 43 7262 8028 12479 ll22a 12286 68956 302,58 334.50 Sl9,96 467. 50 511.91 2873,15

• 0.10 ~

---

0.06-------o-;ot~ -----o; 02 ___.-- -

a.cu 0,03 0.02 0.22 o.as a.01 0.01 0.01 0.01 0,01 0.36 0,57 l+,89 1.13 0.1+2 l,JO 1,01 0,48 0,28 Q,14 0.22 0.38 O,Ol

.~

a.01 0.01 0,06 0,02 0.01 Ir 0,05 0.01 0.04 Q,03 0.01 0.01 o.a2 0.18 0,13 a,15 0.12 0.11 0.14

.~

0,07 0.02 a.05 0,02 a.01 0.04 0.23 0,26 a.21 0,25 0,06 a.22 1,70 0,84 0,50 0,23 o.36 a.62 2,47 2.28 1.27 l,.58 l, 17 1.61 v 12,3.5 9,10 4,85 l+.83 3,.55 7.28.

0.25 a.19 a.09 0.12 0.15 o.2a a.34 0 *.53 a.28 o.os a,28 0,28 0.02 0,03 a.01 0.01 0.02 a.02 4,93 J.24 1,45

1. 27 2.11 Z,46 S.63 s.21

z. 71 3.21 3,30

3. 79 0.01 O.Ol a.02 0.02 0.04 0.02 111.08 97.76 59,88 24,68 18.98 55,73 /

0.10 o.u a.2a

o. la a,16 0.12 a.at

-~

a.10 0,06 0.07 0,03 0,03 0,06 o,al 0,01 Q,06 0.01 O,OJ

~

Jr....

~ _____ _ Tot11L _____ 13a,4a ___ 62.10 __

42,.1+9 _ ~lOB.42 __ 141,.09------121,07 __ n, U--38 *.ll --31.63--74, 53 __ ------

~.: " y:

• .~:.. 'l

~c; t

• Leao than 0,01 7.2-8

• 'f.*

r r... '...

~

~.. r.

l t l J, l *

'f..

I'. *.

)'

i*'

t *......

')"

t. I

'i.

• 1,

I i

r.* '

t l

• ,~ I

~*

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• j J "

.~...

i I ".

j.

1.i

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• .:f \\

'l'ABL~ 7.2.?-$

Catch per effort (number per 10 min haul} for fishes collected by 16 ft semi-balloon trawl in Trawl 405 during preoperatlonal (1966-1973) and postoperational (1974) periods in Conowingo Pond,

'fear 1966 1967 1968 1969 1970 1971 1972 1973 1974 No. Collect Lons 18 59 37 62 107 188 223 2!*0 275 No, Species 13 17 19 19 2l 21 20 11 23 Species 11* rostrata

~':

o. cee;;d1'1num o.a1 0,05 0.01

£. au rat us a.al 0,ltO

£. carp to 0.22 0,36 0,43 0.81 0.38 2.19 l.84 0,67

.!:!* cryso L<!ucas O.ll O.la a.La a.10 O.la a.04 a.as a.01

.!:!* ainoenus a,01 o.al

!:!* hudson lus 0.94 a.78

o. 78 3.66 3,69 2.46 a.34 0,09 a.32

!!* procne a.01

~* sp1.loeterus 0.04 a.al o.a1

f. notatus 0.02

a. U a_. ~ulatus

£* cyprtnus 0.06 0.03 0.02 0.02 a.02 a.01 a.al

£. cotT1E11et'sonl a.02 a.05 0.02 a.OJ

~* macrolepidotum 0.22 0.02 O,OJ a.a2 l* cat us o.so o.so 0,05 0.23 o.a7 o.os O.al I. n.ttalts a.OS 0.02 0.07 l* nebula*..!!.'!

0.67 0.73 0.86 1.39 0.69 0,38 0.02 0.13 1* eunctatus 19.61 19.39 29.89 163.23 113. 7a 7t.76 12.33 6.31 14.76 il* rupestris 0.02 0.01 1* auritus 0.02 o.az o.a2 L, cyanellus 0.05

!;. gibbosus 4.0a 0.83 l.72 5.61 0.93 2.77 0.21 0.03 0.58 1* macrochlrus 7.72

l. 76 7.21 7,90 l.28 6.57 0.21 0.09 0.68

!:!* dolomie.ui 0,02 0.02 0.27 0.02 tl* saln101des 0.02 o.os 0.13 O.Ol 0.01 r_. annularis 187.61 23.68 9.l3 60.47 22.93 47.88 23,07 0.31 1.32 f* nigromaculatus 0.11 o.oz O.Ol 0.02 r;.. ol111Stedi l.17 l.54 1.48 J,2.9 0,87 2,20 0.17 0.47 3.39

!* flav-;sccns Q,02 0,16 o.os 0,05 0.01 0.02 y_. cnprodu 0.02.

§.. ~

0.05 0.05 0,06 0.04.

0 07 Ol Total 222..94 49.41 52.13 247.50 144.90 136.56 38,44 7.79 22.03

• Less than O.Ol 7.2-9 Zone Total 12a9..

3l a,Cil.

1:02 a.04.

1.13 0.01 0.01 o.al o.al 0.01*..

0,04 a.31 38.63 l, 13 2.18.

0.02 O.Ol 21.4?

O.Ol l.62..

0,02 0.03 67.72

TA.'3LE 7.2.2-6 Catch per effort (number per 10 min haul) for fiahea collected by a 16 ft aemt*balloon travl in Travl 408 durtns preoperational (1966*1973) and postoperational (1974) period* in Conovingo Pond.

Year 1966 1967 1968 1969 1970 1971 1972 1973 1974 No. Collections 9

36 44 32 119 179 222 228 276 No. Species 15 15 21 23 20 21 22 22 27 Species A. ro*t'l'&ta 0.11

--R* cepcdianulll- - --*-- __

• 0.10 2.43 o.os

£*~

0.01

£* carpto 0,11 0.56 0.59 1.50 0,77 1.90 2.19 1.00 0.91

.!!* Ct'YSoleuc:as o.u 0.17 0,63 1.06 0.36 0.09 0.02 0.01 0.17 H* lU'JOenus

~

0.02 0.01 0.02 N, cornucua ji, hudsonlus 2.56 1.36 2.90 7,13 5.62 3.22 0,80 0,62 3.06

!!.* procne

!!* rubeltus 0.01 li*,!Plloptenis 0.02 0.03 0.01 0.16

?* potatus 0.53 0.03 0.01 0,24

£* c:yprinus 0,04 0,03 0.01 0.02 0.07 0.02 C, c:o!l'J\\\\orson i 0.22 0.03 0.09 0,0J 0.01 0,07 0.02 0.02 ii. nigr1cans 0.06 ji. m.acrolepldotum 0.06 0.06 0.06 0.03 0.01 0.01

!* £!S!!!.

0.22 o.n 0.04 0.06 0,04 0.02 0.01 l* !!!_talh 0.01

!* oebulosus 0.67 1,19 1.47 2.31 1.65 l.55 0.39 0.16 0.13 l* punctatus 17.89 17.89 49.86 19.69 59.86 47.18 24.29 19.42 17.23

~* rupe.stris 0,04 0.03

~*~

0.11 0.02 0.03 0.01

.!:* cyaneUus 0.03 0.01 0.01

.b gi.bbosua S.56 2.36 9,11 12.66 2.53 6.77 0.34 1.35 4.04

.!:* 111acrocht rus S.33 4.92 77.86 41.75 4.33 12.54 0,18 3.78 6.11 J:I* dolomieul 0.02 0,44 0.03 0.26 l1* ulmoide.1 0.14 0.06 1.03 0.01 0.04 0.13 l.* annu1"r1*.

61,89 58.11 86,22 354.00 4S.09 132.99 17.18 4.28 10.93

i. n1Rromaculatus o.u 0,04 0.16 0.10 0.06 0.02

!* ol=tedi 0.67 2.28 1.06 1.28 l.os 1.27 0.34 1.52 3.17 P. flavescen.s 0,03 0.36 0,63 0.14 0.06 0.01 o.z,

!.~s-o.u 0.03 0.01 0.02

!* vltreurll 0.06 0.06 0.02 0.04 0.02 0.01 0,04 Total 95.56 89,22 230.65 444 *.56 121.82 207.87 46.00 34.73 47.0l 7.2-10 Zone Total 1167 32 o.5o 1.28 0.16 0.01 2,43 0.04 0.08 0.03 o.03 0.01 0.02 0,68 28.94 0,01 3.39 8.88 0.08 0,08 46.91 0,03 1 *.56 o.u 0.01 0.02 9.5.34

.~

• 1

'"".J

! )

• i

TA!3L~ 7.2.2-7 Catch per effort (nWllber per lO*min haul) for fishes colhcted by 16 ft eeml-balloon trawl ac Trawl Tr11t1aect Stations during preoperational

Pond, (1967-1973) and postoperational (1974) periods Ln Cono.rinso Year 1967 1968 1969 1970 1971 1972 1973 1974 Total No. Collections 93 183 151 145 159 234 268 266 1499 No. Spaciea 18 20 26 23 18 18 18 22 34 Spat:l.H f:.* rostrata

.!!.* cepedhnum o.u 0.02 0.01

~. 111asguinong:i:

0.01

£*~

0.01

£. Carpio 0.34

0. 78 1.07 0.59 1.59 2.29 0,31 0.5!

0.96 J!* C!)'.SOl<!UC89 0.02 0,09 0.13 O.ll 0.06 0.01 o.o:

o.os 1!*~

0.01 0.01 o.o*

!!.*~..!!!.!..

1.08 o.&8 5,97 J,42 1.82 0.21 0.44 1.2'*

1.64

!!.* procne 0.01

!!* *eilneterus 0.01 0.01 o.os 0.02 0,03 0.02 l*~

o.<-7 0.06 o.04 0.02

!* corpot'atl!.

0.01.

£* cyprinus O.OJ 0.01 0.04 0.02 0.04 0.02 0.02

£* commeuonL 0.04 0,05 o.os 0,03 0,01 0.02

!* oblongus O.OJ 0.01

!!o nlgricans 0.01 0.01

~.... croteeldotwa o.os o.oJ 0.03 0.01 0.01 I* m.!!.!.

0.09 0.04 0.20 0.14 0.06 0.02 0.01

(.'1.04 0.06 1* natalis o.oa 0.01 0.03 0.01

!* nebulosus 0,9.5 0.85 1.16 0.86 0.60 0.18 0.06 o.t6 0.49

!.* punetatu!J 21.32

)1.Bl 127.33 104.68 63.82 26,46 11.26 22.26 4.S.02

!-~

0.01 0,01.

0.01

.!,.. cyonellus 0.01

!* gibbosus 0,71 1.79 1.82 1.95 3 *.51 0.18 o.n o.es

1. 1.5 1!* macrochirus 1.75 17.62 S,J6 o.92 6.74 0.14 0.74 1.41 4.01 J:!, dolomleul O.OJ 0.01 0,16 o.04 o.06 0.03

~. ealmoidcs 0.02 0.01 0,05 0,04 0.01 0,01 0.01

!* *nnularis 16.26 14.13 113.90 31.59 41.30 5.97 1.1, 2.04 23.14

!* nlgro:naculatus 0.04 0.02 0.()4.

0.02 0.01 0.02 0.02

!* olmatcdi

2. 53 0.96 1,71 o.n 1 *.53 0.19 0,69 4.64 1,66 l* flave*ccna 0,08 0.31 0.11 o.04 o.04 Ir 0.02 0,07

!* caeroJe!I 0.01

!* pelcaca

!* tlll'.!.!!!l 0.03 0,02 o.os 0,04 0,03 0.02 0.02 Total 45.J4 69.43 259,33 144.37 121.21 3.5.76 15.21 33.59 78.48

• L.. a than 0,01 7,2-11

r!.

(**

('..

~~* *x jL'.

\\t h::

~-f

~ -

j i.;'

.;*/..

~ :,

~-*..

,~.... q i::~'

c*(;

V*.-: r.

/:

!;~"

~t.

~ !'

TA3t.E 7,2,2-8 Yearly comparison of the catch of larval fishes(~ 25.11111) per 10-min tow at Tran.11ect Stations preoperational (1969*1973) and postoperational (1974) periods in Couowingo Pond,

'Ye.ar 1969 1970 1971 1972 1973 1974 Total No.

390 449 471 327 628 696 2961 No

• Species 25 23 17 15 27 26 30 Species --

.,_,,,_.,,..,,.,,.~- ----*---------~- - -

-~------

D. cel!ed1:inum 0,31 0,06 0.08 f* carpio 3.82 2.66 2.31 6.01 4.79 2.33 3.so

!!* crysolcucas 0.01 0.01 0,04 0.01 N. amoenus 0.01 0.02 ji. hudsonius o.04 0.06 0.01 0.02 li* procne 0.01 0.01 N. rubeUus 0.01 j!. spilopterus 0.11 o.oa 0.09 0,03 0.02 0.21 0.11 P, notatus 0.01 0.01

§:. corl!ornlis

.£.* CII!rinus 2.53 4,83 1.10 16.52 7 ~11 3.76 5.46

c. commersoni 0.02 0.02 0.01 0.12 0.04 0.07 0.04 l* catus o.os 0.01 0.01

!* ;at&I1s 0.04 0.01 0.01 1),02 0.01 l* nebulosus 0.02 I. l!unctatus 6.49 2.61 0.63 1.87 1.49 2.10

!. rul!estrh 0,03 0.02 0.01 0.01 0.01

~- aurltus o.os 0.01 0.01 0.01 1* c:z:sncllus 1* gibbosus 0.20 0.04 o.53 0.17 0.01 0.02 0.14 ls~.macrochirus 3.04 0.39 2.07 0.03 0,03 0,0ll 0,82 Lel!omis spp

• l.27 0.46 3.39 0.49 0.30 0~95 M, dalamieui 0.12 0.02 0.01 0.02 j1. l!lalmoides 0.01 0.01 P. annularis 1.97 0.24 1.42 0.09 0.12 0.23 0.61 l* nigromaculatus 0.01 0.01

!* olmstedi 17.75 7.12 5.33 2.11 0.55 17.12 8,64 P. flavescens o.oa 0.02 l* ca2rodes 0.01 P. J:!eltata 0.11 0.14 o.os 0.08 0.13 0.13 0.11

j. vitrewn o.oa 0.04 0.03 0.01 0,03 Total 37.73 18.64 17.08 25.23

.s.54 26.33 22.73 t.'*------

-~----

t.

1 * ~,,

~ :.

• Le11 than 0.01

~ ~

7.2-12

MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE POND MUDDY CREEK FISHING CREEK 0

PEACH BOTTOM ATOMIC POWER STATION STONEWALL POINT STATE LINE-P_A_. -----

MO.

2 SCALE IN MILES PEACH BOTTOM BEACH WILLIAMS TUNNEL WILDCAT TUNNEL GLEN COVE FIGURE 7. 2.1-1 Map of Conow!ngo Pond showing the location of Trap Net Stations.

7.2-13