ML20079M942

316 Demonstration Pilgrim Nuclear Power Station Units 1 & 2,Boston Edison Co

ML20079M942
Person / Time
Site:	Pilgrim, 05000471
Issue date:	07/31/1975
From:	STONE & WEBSTER ENGINEERING CORP.
To:
References
RTR-NUREG-1437 AR, NUDOCS 9111110010
Download: ML20079M942 (184)

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{{#Wiki_filter:.. i l J.O. 12577 4 !I r ,l s 316 DEMO!:STRATION PILGRIM NUCLEAR FOWER STisTION 1 UNITS 1 AND 2 i EOSTON EDISON COMPANY l-i l J 4o i~ JULY 1975 'l -tI !h i I BY ENVIRONMENTAL ENGINEERING DIVISION STOIC f, WEBSTER EDGINEERING CORPOEATION BOSTON, MASSACHUSETTS 9111110010 750731 PDR NUREG 1437 C PDR

TABLE OF CONTENTS Section Title Pace Abstract 1 INTRODUCTION 1-1 t 2 EIiGINEERING AND hTDROLOGIC DATA. 2-1 2.1 Oceanography... 2-1 I 2.1.1 Tides 2-2 2.1.2 Waves 2-2 1 2.1.3 Currents. 2-2 I 2.1.3.1 Tidal Currents. 2-3 2.1.3.2 General Circulation. 2-3 1.3.3 Wind-Induced Motion 2-3 p.. 3.4 Wave-Induced Motion. 2-4 3ay Flushing. 2-4 3 j Initial Estimates of Flushing Rate. 2-4 1974 Analysis of Flushing Rate. 2-5 m j Temperatures. 2-7 'ag-Term Temperature Studies 2-7 2ciperature Studies at the site 2-8 2.2 Stat!.on Characteristics. 2-10 2.2.1 Discharge System. 2-12 j i 2.2.2 Intake System. 2-12 2.2.3 Plume Characteristics. 2-13 l 3 DESCRIPTION OF AQUATIC COMMUNITIES 3-1 1 3.1 Introauction 3-, l 3.2 Benthic Com unity. 3-1 3.2.1 Macrophytes. 3-2 I 3.2.2 Benthic Invertebrates 3-2 l 3.3 Plankton Co= unity. i' -3 3.3.1 Phytoplankton ~ 3-3 I 3.3.2 Zooplankton. 3-0 3.3.3 Meroplankton. 3-4 j 3.4 Fish Com:nu:rity. 3-5 l 3.5 References, 3-6 4 REPRESENTATIVE SPECIES AND RATIONALE 4-1 4.1 Rationale for Species Selection. 4-1 1 4.1.1 Rare and Endangered Species 4-1 I 4.1.2 Commercially and Recreationally Imoortant Species 4-1 4.1.3 Dominant Species. 4-1 1 4.1.4 Nuisance Soecies. 4-2 4.2 Representative 'pecies and Rationale. 4-3 S 4.2.1 Irish Moss (Chondrus criscus) 4-3 4.2.2 Rockweed (Asochv11um nodosum) 4-3 i iii iI

i TABLE OF CONTENTS (CONT 8 D) I section Title Paco I 4.2.3 Amphipod (Acanthchausterius millsi) 4-3 3 4.2.4 American Lobster (Homarus americanus) 4-3 g, 4-4 4.2.5 Blue Mussel (Mytilus edulis). 4.2.6 Common Periwinkle (Littorina littorea). 4-4 i 4.2.7 Atlantic Menhaden (Brevoortia tyrannus) 4-4 4.2.8 Winter Flounder (Pseudoeleuronecte s americanus) 4-5 4.2.9 Pollock (Pollachius virens) 4-5 l 4-5 4.2.10 Cunner (Tautocolabrus adseersur). 4-6 4.2.11 Rainbow Smelt (Osmerus mordax). 4.2.12 Atlantic Silverside (Menidia menidia) 4-6 4-6 3 4.2.13 Alewife (Alosa eseudohareneus). 4-7 5 4.3 References - Section 4 5 LIFE HISIORIES OF REPRESENTATIVE SPECIES 5-1 5-1 5.1 Irish Fbss (Chondrus criscus). 5-1 5.2 Rockweed (Asconhv11um nodosum) 5-2 5.3 A=phipod (Aca nthohaustorius millsi). 5.4 American Lobster (Homarus americanus). 5-3 5-4 5.5 Blue Mussel (Mvtilus edulis) l 5.6 Co= mon Periwinkle (Littorina littorea) 5-5 5.7 Atlantic Menhaden (3revoortia tyrannus). 5-6 5.8 Winter Flounder (Pseudooleuronectes americanus). 5-7 l 5-9 5.9 Pollock (Pollachius virens). 5-9 5.10 Cunner (Tautocolabrus adseerus) 5.11 Rainbow cmelt (Osmerus mordax). 5-10 5.12 Atlantic Silverside (Menidia menidia) 5-10 5.13 Alewife (Alosa eseudohareneus). 5-11 5 5-13 5.14 References - Section 5. 6-1 6. IMPACT ASSESSMENT. 6.1 Procedures for Assessment of the Power Station's g 6-1 E Effect on Selected Species. 6-4 6.2 Irish Moss (Chondrus criscus). 6-4 6.2.1 Thermal Plume. 6-6 6.2.2 Entrainment ................... 6-6 6.2.3 Entrapment. 6-6 6.2.4 Cu=ulative Dnpact 6-6 6.3 Ascochv11um nodosum. 6-7 6.3.1 Thermal Plume 6-7 g t 6.3.2 Entrainment................... 6-7 m 6.3.3 Entrapment. i 6-7 6.3.4 Cumulative Impact 6.4 7.mphipod (Acanthchausterius millsi). 6-3 6-8 6.4.1 Thermal Plume l ~ I iv i m

TABLE OF CONTENTS (CONT ' D) Section Title Pace 6.4.2 F.ntrainment 6-8 6-8 E 6.4.3 Entrapment. 5 6.4.4 Cumulative impact 6-9 1 6.5 American Lobster (Romarus americanus). 6-9 6.5.1 Thermal Plume 6-9 i 6.5.2 Entrainment 6-10 's 6.5.3 Entrapment. . 6-11 5 6.s.4 Cu=urative I= pact 6-11 6.6 Blue Mussel (P.vtilus edulis) 6-11 -I 6.6.1 Thermal Plume 6-12 6.6.2 Entrainment 6-12 6.6.3 Entrapmer.t. 6-13 6.6.4 Cumulative Impact E-13 6.7 Common Periwinkle (Littorina littorea) 6-15 g 6.7.1 Themal Plu=e 6-15 3 6.7.2 Entrainment 6-15 6.7.3 Entrapment. 6-16 6.7.4 Cumulative Impact 6-16 1 6.8 Atlantic Menhaden (Brevoortia tvrannus). 6-17 6.8.1 The Model. 6-17 6.8.2 Results of Thermal Plume, Intrainment and Impingement. 6-19 6.8.3 Cumulative Impact 6-20 6.9 Winter Flounder (Pseudocleuronectes americanus). 6-N 6.9.1 The Model. 6-21 I 6.9.2 Results of Thermal Plume, Entrainment, and Impingement 6-22 6.9.3 Cumulative Impact 6-23 6.10 Pollock (Pollachius virens) 6-24 6.10.1 Thermal Plume 6-25 6.10.2 Entrainment 6-25 1 6.10.3 Entrapment. 6-26 6.10.4 Cumulative Impact 6-26 ........., 6-26 6.11 Cunner (Tautocolabras,a_dscersus). 6.11.1 Thermal Plume 6-26 6.11.2 Entrainment 6-27 6-27 6.11.3 Entrapment. 6.11.4 Cumulative Impact . 6-27 I

6. 2 Rainbow Smelt (Osmerus mordax).

6-27 6.12.1 The Mocel. 6-28 6.12.2 Cumulative Impact 6-31 v I

E TABLE OF CONTENTS (CONT ' D) g 3 Section Title Me 6.13 Atlantic Silverside (Menidia_ renidia) 6-31 6.13.1 Results of Thermal Plume, Entrainment and Impinge-ment 6-32 6.13.2 Cumulative 7mphet 6-32 I 6.14 Alewife (Alosa pseudoharenau_s,). 6-33 i 6.14.1 Results of Thermal Plume, Entrhinment and 6-33 Impingement. 6.14.2 Cumulative Impact 6-34 l 6.15 References - Section 6. 6-35 5 g 7 SUIS'.ARY OF ENVIRCNF.LNTAL IMPACTS AND CONCLUSIONS 7-1 7.1 Introduction 7-1 7.2 Summary of Individual Species Impact 7-2 7.3 Conclusiens. 7-3 Appendix A. Hydrothermal Data. A-1 Appendix 3. List of Ecological and Hydrographic Studies Associated with Pilgrim Station. 3-1 I I 1 I I I I V1 mm 5

I LIST OF TABLES I Table Title 2-1 Commonwealth of Massachusetts, Water Quality Standards for Coastal and Marine Waters Assigned to Class SA 2-2 Monthly Averages of Water Temperature (OF), Offshore I Pilgriu Site and Unit 1 Condenser Intake Temperatures 2-3 Pilgrim Station Cooling Water Characteristics (Full Loac) 2-4 Typical Ioad-Dependent Operating Conditions (Units 1 and 2, Combined) 2-5 Discharge Characteristics for Various Tidal Conditions 2-6 Travel Times from Condenser Inlet to Cape Cod Bay i (Minutes) 2-7 Intake Water Velocities 2-8 Predicted Surf ace Areas Within Various Jxcess 'lemperature Isotherms (full power operation of Unitu 1 and 2) 4-1 Estimated Commercial Catch or Harvest (lbs) in the Vicinity of Pilgrim Station 4-2 Sport Fishing Catch at Pilgrim Station (1971 - 1972) 4-3 bhecklist Summary of Representative Species and I Rationale N 6-1 Irish Moss Har"est Characteristics: 1971, 1972, 1973 W and 1974 6-2 Parameters of the Menhaden Population Simulation Model 6-3 Simulated Equilibrium of Menhaden Population 6-4 Results of Simulation of Menhaden Population 6-5 Parameters of the Winter Flounder Simulation Model 6-SA Results of Winter Flounder Simulation Over a 40-Year Period 6-6 Species Composition of Gill Net Collections 6-7 Sport Fishing Cutch at Pilgrim Station, 1974 6-8 Life Table for Smelt 6-9 Initial Population Structure for Simulation l vii

LIST OF FIGURES Ficure Title 2-1 Location of Pilgrim Site 2-2 Surf ace Water _Te:nperatures at Cape Cod Canal and boston R Tide Stations T 2-3 Daily Maximum, Minimum, and Average Temperatures at Various Depths, Cff shore Pilgim Station (June 1970 - g October 1970) N 2-4 Daily Maximum, Mini. mum and Average Temperatures at various Depths, Offshore Pilgrim Station (Novem.ber 1970 g March 1971) g 2-5 Daily Maxi:num, Minimum and Average Temperatures at various Depths, Of f shore Pilgrin Station (April 1971 - August 1971) 2-6 Daily Maximum, Minimum, and Average Temperatures at. Various Depths, Offshore Pilgrim Station (September 1971 Jar.uary 1972) 2-7 T%ily Maximum, Minimum, and Average Temperatures at various Depths, Offshore Pilgrim Station (Febru&ry 1972 - July 1972) g 2-8 Daily Maxi:num, Minimum, and Average Temperatures at g Wrious Depths, Offshore Pilgrim Station (August 1972 - January 1973) g 2-9 Daily Maximrn, Minimum, and Average Temperatures at 3 Various Depths, Offshore Pilgrim Station (Fe.5ruary 1973 - June 1973) 2-10 Weekly Temperature Ranges Extracted from 'Ihermograph Records at Three Depths 2-11A Comparison of Of f shore and Unit 1 Intake Seaweter l Temperaturer-January through March, 1973 2-113 Comparisen of Offshore and Unit 1 Intake Seawater Temperatures - April, through June, 1973 i 2-12A Comparison of Of f shore and Unit 1 Intake Seawater Temperatures - July through Septe:nber, 1973 2-123 Comparison of Offshcre and Unit 1 Intake Seawater Temperatures (October through December, 1973) 3 2-13 Progressive Formation of Seasonal Thermocline in Cape E Cod Bay 2-14 Sea Temperature, Wind, and Current at Pilgri:a Site (1971)g 2-15 Circulating Water Syste n Schematic g 2-16 Discharge Channel 2-17 Discharge Channel Profile and Cross-section 2-18 Intake Structure - Unit 1 2-19 Intake Structure - Unit 2 2-20 Low Tide Sea Surface Isotherm Map 2-21 Predicted Vertical Excess Temperature Profiles Along Plume Centerline - Units 1 and 2 - High Tide 2-22 Predicted Vertical Excess Temperature Profiles at Maximu:a Plume Nidth (Tycical) - Units 1 and 2 - High Tide viii E;

LIST _OF FIGURES _(CONT 8 DL Ficure ,T,,111_e, l 2-23 Predicted Vertical Excess Temperature Profiles Along Plume Centerline - Units 1 and 2 - Low Tide '2-24 Predicted Vertical Excess Terperature Profiles at Maxim:n Plu:ne Width (Typical) - Units 1 and 2 - I Low Tide 2-25 Assumed Approximate Extent of Therr.al Effects 2-26 Assumed Thermal Plume Bottom Isotherms (oF) 3-1 Aquatic Communities in Vicinity of Pilgrim Station 4-1 Representative Species g 6-1 Irish Moss Harvest Areas in Cape Cod Say, in Vicinity 5 of Pilsri:n st* tion 6-2 Comparison of Annual Irish Moss Harvest Statistics as Related to Manomet Point i 6-3 Potentia 1 The=al Plume Ef f ects, Irish Moss 6-4 Location of Sampling Stations for Ecological Monitoring Progra:n 16-S Mean Intertidal Asconhvilu:n nodosum Density in Dry Weight (g/m2) 6-6 Mean Density of Acanthchavstorius mills.t at 10 Feet Below MLW ~ 6-7 Lobster Pot Sampling Grid 6-8 Mean Lobster Catch Per Pot 3 6-9 Potential Thermal Plume Ef fects, Lobster 3 6-10 Mean Intertidal gv_tilus Density 6-11 Potential Themal Plume Effects, Mussel 6-12 Mean Inte.rtidal Density of Littorina littorea g.g (no. per m2) 6-13 Potential Plume Eff ects, Periwinkle ( 6-14 The Ricker Stock and Recruitment Function from .l Schaaf and Huntsmun (1972) 6-1S Menhaden Landings for All Massachusetts Ports 6-16 Winter Flounder Trawl Catch 6-16A Depth-Averaged Particle Paths; Velocities Taken from " CASE" Using Tide and 10-Knot Southwest Wind i 6-163 Depth-Averaged Particle Paths; Velocities Taken from _g " Cart " Using Tide and 20-Knot Southeast Wind E 6-17 numbers of Pollock and cunner collected in Gill Nets at ). Rocky Point in the Vicinity of Pilgri:n Station I 1 i I a 1 1

1 ABSTRACT I The following document is a denonstration pursuant to Sections 316 (a) and 316 (b) of the Federal Water Pollution Control Act for Pilgrim

Station, Units 1

and 2. The demonstration includes acpects of Type 2 and Type 3 demonstrations as defined in the draft guidance

ranual published by the Environmental Protection Agency in September 1974 The denonstration analyzes engineering, hydrological end biological, da ta pertaining to Pilgrim Sta tion and the I

surrounding waters of Cape cog Bay. It presents an assessment of the environmental ef fect of Pilgrim Station on the surrounding waters of Cape Cod bay. The assess:aent is supported by an analysis which conservatively establishes quantitative esti. mates of sta tion-induced nortality I for each of the representative species. The assesstnent concludes that no udverse effect to a bale. aced indigenous population or shelitish,

fish, and wildlife in the surrounding waters is 3

expected as a result of the operation of Pilgrim Station, Unita 1 5 and 2, with the proposed once-through ecoling systems. It demonstrates that environmental c:ffects resulting from the operation of the proposed once-through cooling systems associated vrith Pilgrim Station, Units 1 and 2, are minimal and that the requirenient to provide clos ed-cycle ccoling i,s nore stringent than is necassary to ensure the protection and propagation of a balanced indigencus population of shellfish, fish, and wildlife in and on the receiving waters. I I I B I I I I

SECTZON 1 INTRODUCTION The Federal Water Pollution Control Act Amendrents of 1972 I require steam electric generating power stations st!ch as Pilgri:n Station to have the best available control technology by 1983 for rainimizing the discharge of pollutants. This has been interpreted for thermal discharges as some form of closed-cycle 8 cooling. Under the 316 (a) exemption, alternate effluent limitations may ba granted if the Applicant can demonstrate that the erfluent limitations are more stringent than are: I necessary to assure the protection and propagation of a balanced indigenous population of shellfish, fish and wildlif e in and on the body of whter into which the discharge is to be made...". With respect to the effects associated with the

intake, Section 316 (b) of the Federal Water Pollution Control Act Amendments of 1972 spe cifies that the location,

design, I

cons truction, and capacity of the cooling wuter intake structure shall reflect the best technology available tor mini =izing adverse environmental irapact. This report considers the effects of both the sta, tion discharge and

intake, and addresses both Section 316 (a) and 316 (b) requirements.

It utill:es technical guidance from both Type II I and Type III de:aonstrations, as described in the draft technical guidance manual used by the Enviro:unental Protection Agency in Seotenber 1974. Since the proposed Unit 2 di.:: charge will be combined with the Unit 1 discharge, this demonstration considers the combined effects of both units 1 and 2. The data for the analysis of ecological, engineering, and I hydrologic intormation on which the 316 demonstration is based are aported in the Applicant's Environmental Report and AEC Enviro:unental Impact Statements for Pilgrim Sta tion. Various I reports and res ults of environmental and engineering studies associated with Pilgrm Station have been used. Pertinent scientific literature has also been used and referenced in preparation of the de:aonstration. The demonstration presents data describing the oceanography of the water surrounding Pilgrim Nuclear Power Station. The design l and operation of this station is described as it affects the intake and discharge of the circulating water system. I The aquatic community of Cape Cod Bay and the water surrounding Pilgrim Station is also described; these include benthic con = unities, planktonic con = unities, and fish communities. The report outlines the rationale for selection of representative species considered by the demonstration. A list of .3pecies is I 1-1 5 I

giver and the rationale supportina the selection of each species is dereloped. Life history characteristics of the representative species are also described. s The denonstration contains assessments of Pi.lgrian Station's impact on the representative species. The analysis considers the 18 effects of entrain:nent into the circulating water

system, entrapment at the intake structures, and of fects relating to the g

thermal discharge of the station. The impact assessment approac.. 3 i in this document is to identify potential i= pacts which could

occur, and, baseci on available data and expected station a

E characteristics, to quantify the effects of the station on representative species. This analysis requires that a number of conservative assumptions be made which overstate the magnitude of the station-induced effects. This

results, howeve::,

in quantitative impact deterrainations which otherwise would not be possiole. A summarv is presented containing the predictions developed in the the quantitative analysis and provides judgne:its relating to ~ expected environmental impact caused by Pilgrim Station. i E .d i I l I 8 l L I 1 l l I ,i l 1-2 I And I E o

SE.CTION 2 ENGINEI."AlNG AFD EYDROLOGIC DATA This section prescats engineering data relating to the design and operation of the circulating water systems for Pilgrin Station. Oceanographic information for Cape Cod Bay and the waters surrounding the station are also presented. This material has been selected ca thh basis of its relevaancy to the 316 I Demonstration. Additional and more detailed information may be obtained frcca the final environmental report for Pilgrim Station, and the semi-annual reports listed in Appendix A which describes I marine ecology and hydrothermal studies. 2.1 OCEANOGRAPHY E Physical oceanographic characteristics near Pilgrim Station are influenced primarily by characteristics of the Atlantic Ocean and of Cape Cod Bay. The station location relative to Cape Cod Bay is shown in Figure 2-1. Cape Cod Bay is a broad, open-mouthed vater body formed oy the I eastward and northward extension of Carre Cod fron the coast of Massachusetts. The routh is not well harked on the western side, a line extending from but for the purpose of this description -I Race Toint westward to Green Barbor is considered to designate ~ the mouth of Cape Cod Bay. The length of this line is 17.5 nautical riles. The Bay's greatest width (24 nautical riles) is along an east-west line near its southern limits. The north-south dimension of the bay is slightly les.s than 20 nautical miles. I Cape Ccd Bay has a surf ace area of approximately 365,000 acres. D: cept for the southeast corner of the Bay at Billingsgate Shc.al, depths generally increase rapidly with distance from the shore. I The greatest depth, approximately 180 feet, occurs at the mouth of the Bay. Approximately half the surf ace area of the Bay has depths greater than 100 feet; the voltrae-mean depth is also I approximately 100 feet. The water volume of Cape Cod Bay is approximately 3.6 x 107 acre-feet. Ste11wagen Bank is located north of Race Point, outside Cape Ced Bay. Ste11wagen Emk influences the physical oceanegraphy of Cape Cod

Bay, particularly in its ef f ect on wave a ction.

The I Bank is an area with typical minimum water depths of 80 feet. For the purpose of this description, the limit of the Sank is defined by the 120-foot depth contour. The Bank is approximately l 20 nautical miles long and varies in width from 2 nautical miles at its northern end to 7 nautical miles at its southern boundary. I 2-1 I

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These waters in the vicinity of the site are assigned to Class SA, Coastal and Marine Watern of the Massachusetts Water o Quality Standards adopted by the Massachusett:. Division of Water Pollution control on March 3, 1967. Table 2-1 presents the standards of quality for Class SA waters. The following sections provide details on tides, waves, currents, I bay-flushing, and temperatures, of the waters in the vicinity of Pilgrim Station. 2.1.1 Tides Tides at Pilgriza Station are comidiutmal (two high waters and two 'E low waters each 24-hour period). Tide records for the area are 5 available from the U. S. Coast and Geodetic Survey Tide Stations located in Boston Harbor. Tide data are published annually for Gurnet Point and Plymouth. Tide levels at Pilgri:a Station are similar to those at Boston. The mean tidal range at Soston is 9.1 feet, and the spring tidal range is 10.6 feet. The datum relationship at Pilgrim Station is that mean sea level is 4.78 feet above mean low water (MLW). The estimated average yearly maximum astronomical high tido is +11.7 feet

MLW, and the estirated average yearly minimum astronomical low tide is -2.3 feet MLW.

The highest s till-wa ter tide level recorded in this area is a + 15. 3 f ee t MLW. This level occurred at Boston on February 24, j 1723. Tide levels of +14.8 feet MLW have occurred once in 1851 and again in 1909. 2.1.2 Waves i The Pilgrim St.a. tion site is exposed to waves generated in the North Atlantic and that approach the site from the north through 60 degrees east of north (N 60aE). The site is sheltered from other distantly generated wave-approach directions by Cape Cod to the ehst and the Massachusetts and Maine coastlines to the north. Wave refraction analysis has indicated that the maximum-period wave that can reach the area of the site without being significantly diminished in height by refraction is approxirately l 12 ceconds. The site is exposed to locally generated waves from direction N 200E through 5 600E. However, all directions except those from N through N 600E are f etch-li:aited. 2.1.3 Currents The general current regime near the Pilgrim site is a function of tidal currents, geostrophic counterclockwise circulation in Cape Cod

Bay, wind-induced

motion, nearshore wave-induced current, and, at the statian site, local currents induced by the Unit 1 1

~ 2-2 l i

TABLE 2-1 COMMONWEALTH OF MASSACHUSETIS WATER QUALI"Y STANDARDS FOR COASTAL Ido MARINE WATERS ASSIGNED TO CIASS SA Criteria Item Not less than 6.5 mg/l at a time (1) Dissolved oxygen (2) Sludge deposits / solid re-None allowable fuse / floating solids / oil / grease /sctra (3) Color and turbidity None in concentrations that will impair any usage specifically assigned to this class (4) Coliform bacteria Not to exceed a median value of g 70 and not more than 10 samples 5 per 100 ml shall ordinarily exceed 230 dur-ing any monthly sampling period (5) Taste and odor None allowable 6.8 to 8.5 (6) pH Noneexceptwhereincreasewilll (7) Allowable temperature not exceed recommended limits on increase the most sensitive water use (S) Cher.ical constituents None in concentrations or com-binations which would be harm-ful to human, animal, or aquatic life or which would make the g waters unsafe or unsuitable for 5 fish or shellfish or their pro-pagation, impair the palatabil-g ity of same, or impair the 3 waters for any other uses f None in concentrations or com-(9) Radioactivity binations which would be harm-ful to human, animal, or aquati i life for the designated water use. None in such concentra-tions that would result in radio-I nuclide concentrations in aquat { life which exceed the recommenda i limits for consumption by humans j Not to exceed an average of 0.0 (10) Total phosphate mg/l as ? during any monthly i I 1 of 2 I l I 1 1

i TABLE 2-1 (CONT ' D)_ j -Item Criteria sampling period (11) Ar:monia Not to exceed an average of 0.2 mg/l as N during any monthly sampling period Note: Class SA = Suitable for any high quality water use includ-ing bathing and water contact sports; suitable for approved shellfish areas. I 4 i 8 1I ,I t g iI I g i I iI i 2 of 2 ~ 8 I

circulating-water intako and dischargo. Studios indicate that tho tidal component of the currents is weak in the inshore waters l off the station site out to a distance of about 3/4 mile from shore (water depths 40 feet and less). The local water movement near the station site is strongly to wind action. 2.1.3.1 Tidal Currents Results of maasurement and analysis of tidal currents at Gurnet E Point, Manomet Point, and 1 mile E of Ellisvil]e Harhor have been W published by tha U.S. Coast and Geodetic Survey. Tidal currents along the western and southwestern side of Cape Cod Bay are a generally directed parallel to the coast, except in or near the E entrances to appended harbors. Maxi:mm ebb and Ilood currents appear to vary considerably f or the three U.S. Coast and Geodetic l Survey locations nearest the station site. The maximum tidal currents for the Gurnet

Point, Manomet Point, and Ellisdlle Earbor area vary from 0.3 to 1.4 knots.

Mari:num tidal currents determined from measurements at stations located approximately 1/2 mile and 1 mile offshore from the Pilgrim site are 0.08 knot and 0.25 knot, respectively. TheR direction of these current changes with tidal stage in an W ' elliptical rotary f ashion. 2.1.3.2 C-eneral Circulation Information on the general pattern of flow in the northwestg Atlhntic off the coasts of the New England states and theg l Maritime Provinces of Canada shows that a coastal current flows southward along the coast of Maine and Massachusetts (Oceanocranhic Atlas of the North Atlantic Ocean, Section 1: Tide _s and Currents, U.S. Saval Oceanographic Office Publication No. 700). A portion of the flow enters Cape Cod Bay along the western shore of the Bay, circulates counterclockwise, and leaves the Bay on the eastern side. The flow then swings eastward around Cape Cod and finally southward. Interpolation of the speed given in Reference 5 suggests that theg isopleths of mean probable average speed of this counterclockwise flow in the bayE is not less than 0.3 foot per second. 2.1.3.3 Wind-Induced Motion The speeds associated with the tidal ro11on and with the generalm circulation pattern in Cape Cod Bay are in a range suggestingg that wind-induced motion will at times dominate the flow. Wind blowing over deep water produces a direct wind-driven motion in the surface layers directed to the right of the wind in the Northern Eemisphere. In shallow water, the wind-induced flow is more nearly in the direction of the wind. The speed of the wind-1 induced surface flow has been shown to be roughly 2 percent ofE the wind speed.* Thus, a wind rpeed of 15 knots would induce a5 surface current of about 0.3 knot or 0.5 foot per second. c

• Applies for wind speeds measured at 30 feet above water surface g

2-3 i am 5

4 2.1.3.4 W6ve-Induced Motion (( Waves approaching the shore at an angle will induce longshore l currents. The Pilgrim Station site is exposed to wave action N through N 600 E, and it can therefore be expected that wave-induced current will generally be directed down the coastline toward the southeast, i.e., in the same direction as flood-tide currents and the geostrophic circulation in Cape Code B6y. Additional longshore currents may be induced by the mass i I transport of water towards shore by waves. 2.1.4 Bay Flushing lI The waters of Cape Cod Bay are exchanged for "new" water from outside the bay by at least three processes: Tidal exchange The general counterclockwise circulation Wind-induced motion These processes are amenable to first-order numerical estimates I of the fractional rate at which the waters of the Bay are replaced by "new" water. f 2.1.4.1 Initial Est'imates of Flushing Rate Prior to the availability of any long-term current meter measurements in Cape Cod Bay, the flushing rate was estimated by .I Dr. D.F Pritchard of the Chesapeake Bay Institute as follows. 3 The intertidal volume (i.e., the diff erence in tne volume of the 5 Bay at high water and at low water) represents approximately 9.3 preent of the mean volume of the Bay. This means that 9.3 percent of the volume of the Bay moves in and out through the mouth each tidal cycle. Experience in other coastal vatar bodies has shown that perhaps as much as

• <0 to 80 percent of the water

~ that leaves the Bay on ebb tide returns to the Bay on the next flood. The remaining 20 to 30 percent represents new water, and two tidal cycles occur each 24.84 hours. Assuming a 20 percent exchange rate on each tidal cycle, the Bay water renewal rate by tidal action is thus about 3.5 percent per day. The inflowing current ut the mouth of the bhy, with a mean speed 'g of at least 0.3 fcot per second, is conservatively estirated to 3 occupy at least a third of the cross-section of the mouth. 2'he mean dapth at the mouth of the Bay is 150 feet, and the width is 17.5 nautical miles or 1.06 x 105 feet. The cross-sectional area 'I_ of the mouth is therefore 1.6 x 107 square

feet, and the fractional rate of renewal by inflowing current is about 8.8 percent per day.

i 2-4 4

The carly estimatos did not attempt to quanaOfyf'@Rinfgsmmty action related to wind-induced motions. When all circulation offects are taken into account. however, it was estimated thot l! tho mean renewal rate would be at least 12.3 percent per day. A renewal rate of 12.3 percent per day would provide a mean residence time of 8 days for water or for any water-borne component. 2.1.4.2 1974 Analysis of Flushing Rate The description given above of the long-term mean circu] ation was based on into and out of Cape Cod Bay, and within the Bay, data summarized on charts contained in Oceanogranhic Atlas of the U.S. Naval North Atlantic Ocean, Section I, Tide-md Currents e Oceanocrach @,Ofrice Publication No. %. The estimate of 0.3 ft 2 sec-1 for the current flowing into L.4 e Bay along the western shore was obtained by interpolation of the isopleths of mean speed given in the ref erenced publication. Analysis of current meter data collected at Station A, located in 32 feet of water (F1W) approximately one-hal. mile offshore from the plant site for the period April 20, 1973, through August 28, 1973; and at Station B, located in 53 feet of water (F1W) 3 approximately 1.3 miles offshore from the plant site for the 5 period August 14, 1973 through Novemb3r 1, 1973 gives the following results. Tidal currents at both stations exhibit an g foot sec-1 at g elliptical rotary flow, with an amplitude of 0.14 the inshore station and 0.42 foot sec-1 at the offshore station. was 0.038 foot g The long-tern mean nontidal current at Station A sec-1 directed toward the ESE, and at Station B, 0.000 foot sac-1 g directed toward SE. These values are considerably less than the 0.3 foot sec-1 flow which had previously been estimated as the The speed of the nontidal counter-clockwise flow around the Bay. low' values of long-term mean nontidal current observed at Station A and Station B do not negate the possibility that a circulation having current speeds on the order of 0.3 fcot sec-1 g exists further of fshore from the plant site.

However, these observations do warrant a re-evaluation of the flushing rate of Cape Cod Bay.

The analysis of the current observations at Station A and is a Station 3 shows that the short-term nontidal residual current directed very nearly parallel to

shore, and is strongly g correlated with the wind velocity.

The wind factor relating the speed of the wind measured at 300 feet elevation to the speed of a the wind-induced current varied depending on the angle of attack g of the wind at the coastline, with an average value over all wind l directions of 0.0082. This is consistent with the accepted value of approximately 2 percent for winds measured at anemometer height (30 f eet), and approximately 1.5 percent for winds measured at 75 feet elevation. B l w:: l i o 3 t 1 ~

In view of the lack of verification of the assumed flushing flow I through Capo Cod Bay having c speed of about 0.3 toot sec-1, consideraticn of wo other flushing mechanisms is pertinent. In ovaluat ing the ra+,e of supply of new dilution water to Cape Cod I

Bay, it

..a the long-term (on the order sf annual) mean flushing rates which should be considered. W see

this, note that the ratio of the volt:ne of Cape Cod Bay (1.6 x 1012 it3) to the rate l

of discharge ci' condenser cooling water flow giver the time interval ovar which this voltrae could supply the condenser cooling water flow for ti,n plant. For Unit 1;o. 1

alone, this I

time interval is 70 years and for Unit tio. 1 plus Unit !Jo. 2, the subfect ratio is 21 years. The significance of these relatively long time periods is that the volume of Cape Coc Ec,y acts as an ef fective buff er, c:a:>othing out short-term variations in the I flushing rate of the Bay. The annual mean flushing rate of Cape Cod Bay due to wind-induced I circulation is considered as follows. The Bay opens to the north, so that a wind having a component from the north would set a up an inflow into 8.:he Bay over the upper layers of the water q column and an outflow from the Bay over the lower layers of the water column. A wind having a component from the south would set up an outflow in the upper Icyers and an inflow in the lower I layers. An analysis of the annual wind rose observed at the 72-foot level at the Pilgrim Station gives a value of 9.5 mph for the average north component of the vind for -winds from the s e.-d.-circle. The average south component of the wind I northern for winds f 2:om the southern semi-circle is also 9.5 mph. The wind-induced surface currents resulting from a 9.5-mph wind, as be 0.21 foot sec-1 (since I ' measured at 72 feet elevation, would m.. the wind factor for winds measured at this elevation is approximately 1.5 pereent). This cunent would flow out of the Bay for winds having a component frcrn the south and into the Bay B for winds having a eccponent from the north, with a counter flow occurring in each case in the deeper layers. Both observation and theory suggest that the steady-state wind-induced flow in l such situations varies linearly with depth in the upper half of the *ater coluna.

Thus, the mean speed of the wind-induced circulation over the upper layers would be 0.105 foot sec-1 The approximately east-west cross-section marking the mouth of Cape Cod Bay has a area of 1.6 x

107 ft2 The wind-incuced inflow to the Eay for the average northerly component of the I sind, or outflow from the Bay for the average southerly component of the

wind, would occur over about the upper one-half of the cross-s ection.

The rate of supply of "new" dilution water to the I Bay as a result of wind-induced circulation is then, on an annual average, approximately 7.21 x 1010 ft3 day-1 This corresponds to a renewal rate of the volume of the Bay due to wind-induced I circulition of: 7.21 x 1080 fts day-1 = 0.045 = 4.5% per day I 1.6 x 10** ft3 w

• • h I

The macn rcngo of tidoc in capa Cod Bay ic 9.3 teot. Since the t.he volumo mean tido 10 very nearly a standing wavo, and since thefractionalchangeinl depth of tho Bay is about 10v fect, volume of the Bay during eno tidal cycle is 0.093, or 9.3 percent. Though the interpolation of the isopleths of mean current speed given in Oceanocraphic

st.l a s of the Jorth htlantic Cm e an,

Section I, Tides apd Cu 1:aval Oceanocrachic Offjce l D bJication Jio. 700, Ts' qu_rrents, U.S. estionable for flows wietin Cape cod a Ba y.,

Thia, procedure is probably valid for the flow which moven southward along the coast of Maine and P.a ssa chusetts,

then 3 eastward across the mouth of the Bay and around Cape Cod. The 3 average speed across the mouth of the Bay, as deduced from the above-referenced

document, is about 0.36 foot sec-1 Hence,g during a tidal cycle the water off the mouth of Cape Cod Bay is g displaced eastward by 1.61 x 10* feet, or 0.151 of the length of the cross-section at the mouth.

Therefore, an average of at 15.1 percent of the water ahich leaves the hay on each ebb l least l tide does not re-enter the Bay on the next ficed

tide, being replaced by "new" water.

Therefore, the rate of renewal of Cape Cod Bay by tidal flushing, considering that one tidal cycle takes g 12.42 hours 4s: 24.0_0_ g 0.093 x 0.151 x 12.42 = 0.027 or 2.7% per day y The combined wind-induced and tidal flushing rate of Cape Cod Bayg on a long-term tire scale is then 7.2 percent of the volume oig the Bay per day. Consequently, the rate of supply of new water to the Bay by these two processes in 1.15 x 1011 ft3 day-1, or 1.33 x 106 ft3 s ec-1 Also, the mean residence tir.e f or water, or for any conservative water-borne contamirant introduce d into the bay, would be 13.9 days. I 2.1.5 Temperatures Water temperatures off the Pilgrim Station site have been studiedE since August

1967, and nearly continuous records have beenW obtained since June 1970.

Temperature patterns have been shown to be highly variable, the variability being influenced primarilyg by wind-controlled water circulation. E l 2.1.5.1 Long-Term Temperature Studie3 ag i Data on seawater temperature over. long term have been reported from U.S. Coast and Geodetic Suriey Tide Stations at

Boston, northofthesite,andattheeasternentranceofCapeCodCanal,l l

south of the site. Surface temperatures are measured daily at each station with a single bucket thermor.eter. The depth of areg water at both stations is about 10 feet MLN. Eecords l available for Boston from 1922 to present and for Cape Cod from l 1955 to present. Bottom water temperature has been recordedI 2-7 I 5

continuously at Boston since 1955. Figure 2-2 shows m aimum, minimum, and mean surf ace te: peratures for the Jape Cod Canal and ! I boston Tide Stations. Historical records of water temperatures measured at Boston Light l l Ship and at the eact end of Cape Ccd Canal (see Figure 2-2) show a the wide range of naturally occurring surface temperatures 3 (seasonal variaticns and year-to-year fluctuations) cccurring in i. the total region of ocean waters between outer Loston Harbor and j Cupe Cod Canal. Peaks of these long-term ten erature ranges ar e ll believed to be greater than long-term peak ambient tc:rperatures closer to the Pilcrin site. This is because the water at those somewhat distance sites includen major warm-water intrusions, whose influence is not expected to be felt nearly as much near t the Pilgrim site. These influences are (a) Bu:e. cards Bay water ! i coming through the

canal, which strongly influences average I g temperatures at the east end of Cape Cod Canal, and (b) water 5

from Ecston Harbor and rivers north of Cape Cod

Bay, which influence s the Doston Light Ship temperature data.

The data helow are consistent with this interpretation. I 2.1.5.2 femperature Studies at the Site l Temperature is recorded at a station approxi:utely 2,000 feet offshore from the Pilgrim Site by the Co=onwealth of I Massachusetts Division of Marine Fisheries. Recordings are made . l at 2 feet, 10 feet, and 30 feet (bottom) below water level. Daily

avarages, as well as a

daily minimum and maximum I temperatures from the data octained from June 1970 to December 1 ! E

1973, are shown in rigures 2-3 to 2-12.

seasonal te=perature lW changes and weekly ranges of the temperatures from these l recorders are illustrated in Figure 2-10. Continuous terperature !g dats from the off shore stations and the Unit 1 intake records for !E calendar year 1973 are shown in Figures 2-11A and B through 2-12A l and B. This data is considered to be much more representative of 's seasonal changes at the station intakes than are the data shown g in Figure 2-2, since the water body near the site is not subject to the strong influence of wamer water frcci either Bu::ards Bay or from Boston Harbor. Close exa:nination of the offshore ll l temperature data reveals large daily fluctuations (typically 50F to 100F) superimposed on the core gradual seasonal changes 4.n weekly and monthly average temperatures. The seasonal variations are significently greater near the surface of the Bay than on the

bottom, and seasonal clinatic

'g changes produce a strong tenperature stratification during the W summer months. Generally during the summer and early f all, the Bay temperatures exhibit a 2-layer structure in which a very i, g strong temperature gradient exists at the interf ace of the two g layers (with temperatures decreasing with increasing water depth). More gradual temperature changes generally occur over 4 g the entire depth of the water column within this 2-layer !5 Structura-The 1 cotion (derth) of tho "interf*co" f this 2-i I

I I i 4 60 nt i 'i fl, 1

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. v c. 7.: n .y s 25JAN FEB MAR APR MAY JUNE JULY AUG SEPT OCT NOV DEC JAN Lt0fND MAXIMUM AND MINIMUM MONTHLY TEMPERATURES = BOSTON CAPE COO CAN AL ME AN MONTHLY TEMPERATURES 60STON t., APE COD CAN AL COMPILED FROM: .%rface Weter Temperature & Selinity. At'avlc Coe't of N. & S. Amenes Pub.311,2nd Edition.1905 U.S. Dept. of Comrreece. Coast and Geooetic Survey. FIGURE 2-2 ,,,m e..,..u. - -,......., 5 SURFACE WATER TEMPERATURES AT CAPE C0D CANAL AND BOSTON TIDE STATIONS g I i N 5

e I I 70 I I -,.,&* g i __/__A [ k. ^i. ' d b.Mr'_ f "G p' 14 v y ~ - - sunFAct ~ M 70 j ? ..w +^w"M@#g ,g v (.. rf*]j. 60 i 1 V f D.Dir T H M ) .e-..-- to .I I ii m, . N C M.N-1 i ,'[ jb 7 N qgj.R % .W v"y V'" %W" ~ BOTTCM N 10 20 M 10 20 M to 20 M 10 20 30 10 20 M ~ j jyN 70 JUL 70 l AUG 70 l 5tP 70 OCT 70 e e n.n.,,,3!l7,., n.n.. l TIUURE 2-3, f~-">""""'. DAILY MAXIMUM MINIMUM AND AVERAGE TEMPERATURES l' AT VARIOUS DEhTHSs OFF$HOREPlLGRIMSTATION (JUNE 1970 - OCTOBER 1970) 4 h 1:A./V i - y ! i Y I, i i * ~D%g IY e-j ~ i j t

i 70 6

i ! Y k u p, g, g I l n,, _ u-- 1 ~ i % 1 lt i ! I I i ! l ~ l i l I ! i i I ji i i I 3 I ! t i ,1 l l l i ? i 1 } [ .L. h t. l { ; i Qt;/D*v Ni ! I r 8 M OM + I _i l M.L-- ~ ' I .I i ! I il I ! I ' i I f ! 1 y to 70 M 10 20 30 to 20 M 10 20 '8 to 20 M F t S 71 1 MAM 7) I NOV 70 l DIC 70 t JAN 71 e l FIGURE 2-4,

"!

=:dI;;,.';nt ;l DAILY MAXIMUMS MINIMUMS AND AVERAGE TEMPERATURES I

AT VARIOUS DEPTHS, OFFSHORE PILGRIM STATION (NOVEMBER 1970 - MARCH 1971) I

l, I 1 E "4 : l V '

J%6+~

E u w-I i ' I 1 l g $URFAct j - g i i i i 3 ~ " ~T ; l {, I i i i i i'e i l l i i.,~./,v .% p M M l W ._ ' I WU i ! I ' ' w ,_ p,f. g , i i MID.CEPfH I i G. l t

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i i i. i 4 gi' M 1 WN r !;i4 I,;;,lM h v7Wvm # 't a I }. 1 i i l i i -v serveu 1 5 "Mi, ~ ~ g'0 pg z to 20 30 10 20 30 10 20 30 10 2D 33

m.,i uiv vi sus 71 sut ti Avo ti F!GURE 2-5

n;;=:::Eik:<.':::t; l

DAILY MAXIMUM, MINIMUM, AND AVERAGE TEMPERATUfES m A(T VARIQ RAPRIL 121 EPTHS, OFEltjQBE PILGRIM STATIO g D AUGUST 19/1) l I 10 E 1 i jh% E ,i q. N; I ( F NN " T i 1 gyppggg M 10

i

.i f I l l l 1 i t y i i m I i l MID DEPTH ' ; 7N' } i = 10 i i g i r, i t c i i I w, _w_ i a I ! I 1 T~~ M f. i i i 6 eoriou I ! l. i x 10 70 M to 20 30 to 73 30 10 20 m to 20 30 au ti omi nov vi etc ti

4= n a

em FIGURE 2-6,

n::n.::: r:.; r.':::::

3 DA!LY MAX! MUM, MINIMUM, AND AVERAGF TEMPERATURES a AT VARIOUS DER:'HS, OFFSHOR EJLGRIM STATION 5 (SEPTEtGER 19/.. - JANUARY 19/2) 3g l-em 5 i

lI I l Ii i I il } 'l i I l l t t i I it] } l l l i. l_.,) { l I-I i it 6 iiiiii. i ia 4 '4 'A r - 3 P-i e i i i, M M 7,I ! iiF l "Ii l { i l I . Il _ l I %x. l T. i e' e ii Scapace i ; is i i 9 i i i i i 1 ;i l l i i i i i ii i i I ( i i l 1 i. i I !! I l Il f 11 l

i. 8.d b l e--[ I l

i i I ~~I i lI i _Wf' i 1 li C [ T', j ; i ! i ! l ! I it i i uso.oirm ti i y ; i i ! i i i i i , %A, a l I I i !! I~"I ' l i ! I il i I i l l i i i i i I i i i o i i i T it i ! a i,i i e o i % % 4" i i i ! :, Ii ! I i if I I L Me ! l i ! II t- --Ce ! t t totico i I i 1 ijt I_i l 1 l t I i I to to n to n m to to m to o x to 20 m to

o x eran wAn n mn uAv n sus n suo n F1GURE 2-7

.im; !E! hint *i I DAILY MAXIMUM, MINIMUM, AND AVERAGE TEMPERATURES AT VARIOUS DFETHS, OFFSH"RE P;LGRIM STATION (FEBRUARY 1972-JULY 19721 I 70 % i.( i tj l i i 46 I i i l l l i i l I i ll l l i 1 l I i l ii I if 7 h L g~ i i.1 . l_ i si i ! 1 I i eii ii " "i ii i l g j~s'7Y m 4Ir_i_ iii it ii i i i i il j i I i l j ' 1 i i ! l 1 i il 1 i i SURFACE i I l 11 l l t i~ l ~ i ***WD i 33 I ' ;l j l_ j i L' l_a I i 't I i ! 4 I I i j l I il l 1 l l l I i l i i i1 i i e ll l l i ! l l l l j ~I W ',W i, ? I l'T %f,1 4 I l I I I 11 i l l l l t f~ W M_I l I l 1 1 i l {~ j i i i li ( ) Mic..otPTw j i 14 1 l l' I i T j%i i Y g l_ i t I ! i i t it l l t I i i e I i i it t l 6 i i i l il {_f\\ R N !*./ '4 T I i !! i l HL im ' _1 i i I ! ii I ' i l I I I I -{t* l t i i it i i j i i j ii h % - (_ l _i j i; I il iil I I 5: { i i BorTOM i j i 4 l l !, i-j l l' e "Mi g to 20 30 10 W 30 to ?J 30 to M Jo to 20 30 to 20 3p AUG 72 I $EP 72 OCY 72 ; NOV 72 : Of C 72 I 4AN 73. l FIGURE 2-8

m;;

.: $ih; vel *:

DAfLY MAXIMUMS MINIMUMS AND AVERAGE TEMPERATURES I ATVARIOUSDEPTHS,OFFSHp9/31(AUGUST 1972 - JANURARY G PILGRIM STA110N R l 8

i l 1 x l l i I l i i g w rj i j , -%~ e i r r H - i sumu i i 1 i i i i i. t 1 ii .Lw+V l lTj~ ^D i uso.ot rTH j j y j j ( l ~. n.:. [ } m. l _s o,TTpu, } io n a to n x to a z to a

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• Dait 8 n

t l ANDAVERAGETEMPERATUREj-DAILY MAXIMUMJ MINIMUM) T VARIOUS THSJ OFF ORE PILGRIM STATION FEBRUARY l - JUNE 73J I ,o k _ L,,.a t 1 k t -av-no m_- f,/Q)' c. . fl-Q (2 fe,0 O -) 12 feed _ + - F %.% C .;v : ;- s ..-,..,.- 7, ;.,. ;i, c,:. r C .,f .r N a.4 ..;i. .p _~w ~y,,. y...., 1 - l'4 Lew 2 f. k_ M2 f {M i-P an % Wil feed rfL [hbi5 feed d/ 4_ 3.g i,-,,..* .p.<- ..,. m._': X., w + z ,s./4 . _,.,, m. m..-... .s.

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l . N..r&:~ E af*.. W. " 2 p%e~~=4: l s ~ 3* 7"*--'i I = sxAf ;;... n~,f,,;_ yn.;;;~ y4 E gdp::n'~.,,. *~ % i. x >. --.1

w A

-,3., 88'.-- .mgs.- f p.. I ~: :

=~

'hn~~y.

• l

~~"4-~%,... WP.~~:: s w ~&nw..- E . y, i=n.r e,~,;:: m,_3. g-... w^;p: c_ .pW t~ ~ E ,%_f.:n .. s. = pee %;, ;; t n +.h.... 7 ~,,.,k1 l Y E g .,. = m i _g. -. w f _m.d. % r m .%_~..;,,, 3 _.-s- - - - -.. _--.1 I 1 u.... -_.e:Lg. ' 7 ~.. _. m 8 _. __Ys.2.:2ns

~.

r.h.*:: :..... r~.. .v.., t. E t i ~%n P==mn**a*'="" 3,',' g n ..?+**s* a >r-z. h g, E I g,. -==== %.,,,. i. ? I j j

• "s* Q#

l I f. %y-. ..~ I M.vc. j s,i.,s 11.1 ~h- .f i 4 T "h llil l E 8 .x. T-W.;* j j q, .5 J .6 w u as

• ]

_n l

8l l ,i. I, S$ g i si ui \\ s= i !i g, B5 h*n. 'f e ~~~,g k a i l rt ~ k'? l i. g k g 4.- l l i 3 i I i pb .i 3 T 2i ~ l illl ~@d g-m } m 9 , - >li t i i.. ...r.. m.. g J. L

Icyor temperaturo structuro is generally referred to as the thermoclint. The progressivo formation of the seasonal thermocline in cape Ccd Bay near tha Pilgrim Station is .I illustrated in Figure 2-13, which shows the detailed temperature profile as measured by M.I.T. survey teams at various times of the year. These neasurements were made in the vicinity of the I

station, but outside t!.e detectable influence of the Unit 1 f

discharge. Exact locations associated with each profile are j given in the appropriate references of ambient temperatures ncar 5 the site were summarired as follows (Semi-Annual Report No. 2, Seetion IV) : "A definite 2-layer structure is found to develop in late spring with a thermocline depth varying between 5-10 m, apparently moving up and down with an ebbing and flooding

tide, respectively.

Little variation was found in hydrographic ,I profiles (temperature and salinity versus depth) going along the coastline from north of Rocky Point to White Horse Beach. The position of the thermocline did not change in the direction perpendicular to the coastline." The temperature vs. depth profile shown for 8/30/73 in I Figure 2-13 indicates that at the warmest time of the year the depth of the therrocline is close to the same depth as tne bottom thermograph from which near-continuous records are shown in Figures 2-2 through 2-123. The very strong (~150F) fluctuations in bottom temperatures 1/2-mile of fshore during the su=mer months (Figure 2-12B) are apparently due to fluctuations in the position of the thermocline relative to this location. The frequency of these particular temperature fluctuations generally correspnds to the frequency of the tidal cycle. During the surrner months, when appreciabic stratification occurs in the ambient sea water.), the station intakes are expected to drav primarily water whose temperature is between tN temperatures recorded at the surface and those at the bottom of the water column at the offshore monitoring station. ~ m Average intake water temperatures, are es.pected to be slightly '1 higher than temperaturec experienced in the abs ence of the s station's thermal dis charge due to a small degree of 3 recirculation. Based on the first one--half year of pilgrim Unit 1 operation, the effecu of recirculation on the long-term 3's average intake terperatures is not expected to be significant. J This is based on a comparison of the monthly average temperatares obtained fron the offshore station at three depths with the measurements of renthly average condenser intake temperatures at Unit 1. These data are shown in Table 2-2 for the period l December 1972 to December 1973. Results of a one-week ambient temperature study perforred in September 1971 are shown in Figure 2-14 which include: I 2-9

( ' - dd -e.' I, I d=O t.O ~ C L l. LLt >- vs < y a i ca s d. ,i 6 ' *? LL C Cd pi C gP O i9-b I, }k 1""' 32 ~ da .O. a i,,$ Lg g M' W c 'I s 3 3 10,.. F5 a E ..'*[ O Z W .vs"il, .[, LL. k ! 'I. [ LL.1 LU . 1, Nr > = 3 i i N Co J ~ \\ bo ~ ~ ^ I uJ w w y E. ,e a to c2 o e -a e s e a e o Lg E

• =

Cz:' .C a a r {- C C C C U e, t ~ c4 h g' g w g 7. .2 ny. g 5 5 h. g I g 3 C a E W "i u Y jj a f f' r. h. I E !, l i i i i i . i i o e I : A33d H1430 g J E en W

1 TABLE 2-2 MONTHLY AVERAGES OF WATER TEMPERATURE (CF), 3 j OFFSHORE PILGRD4 SITE AND UNIT 1 CONDENSER INTAKE TEMPERATURES Tenp. at Offshore Station (DF) At 2-ft At 15-ft At Bottom Unit 1 Intake De pth_,, _ Depth 1-32 ft MLW) Temp. (OF) December 42 41.4 42 41.6 1973 January 37 37.3** 36.8 37.3 February 35.1 34.7 36.4 March 39 38.7 36.1** 39.3 April 41 (+) 41.9 42.4 May 47.7 48.4 June 52.6 55.7 ,I July 52.1 52.0 54.3 August 56.8 59.1 54.2 57.6 l September 63.8 60.6 57.3 60.0 g October 55.3 54.2 54.8 54.4 5 November 47.4 48.0 47.4 48.0 1 December 44.5 46.0 45.2 44.6 h . _ _ _ 11eb1e g _ 1 _ _ ,,2 _..e. _ I 'I 1 of 1

o I I I I I I {JT re,nn ioi Q O p C 0.2 0.1 0 02 0.17

an5, ci d

d c1 o 3.7 3.6 10.5 7.1 7.2I gg 62 . SURFACE T 60 BOTTOt.i J T i J Sb f 3 sg 1 e J ) l 54 ,8 8 8 ,8 8 ,8 8 ,8 HIGH TIOE i 9/6 9/7 9/8 9/9 9/10 9/11 9/12

!!

::::!ED:::'.';::!;

FIGURE 2-l'1, l SEA TEMPERATURE, WIND., AND CURRENT AT PILGRIM SITE (1971) I I I E E'

Hourly tm:poroture's at the surfcce and lettom for a o station approximately 1/4 mile off the site (-20 feet IEW), Average 10-foot-deep mean current vector, 1/2-mile

offshore, Anemometer data Mr + ho 70-f rot station at the onsite l

meteorcicgical tower, and Times ot high tide at Plymouth. Comparison of wind and current data shows the Wind vector l directed offshore, while the 10-foot-deep current vector onshore, which indicates that the wind-controlled surface current did not extend to the 10-foot water-column level. Noted during the study I were periods of upwelling followed by periods of downwelling. This was demonstrated by the gonoral decrease in bottom temperatures during the offshore wind period (upwelling), followed by an increase during the onshore wind period I (downwelling). Bottom temperatures at the recording station (-20 feet 12W) are shown to correlate closely with the tide

stage, in a

fachion similar to bottom temperatures at the I ~30-foot !GW station previously discussed. The rapid drop of bottom tempera.ture, usually within an hour of I high tide, indicates that the un.er limit of the cooler incoming deep floodtide water was close to the depth of the instrument (-20 feet MLW). This seasonal thernocline exis ts during } l approximately June through late October and November. The study indicates that fluctuations in the water-column temperatures also occur due to: Upvelling, when the offshore winds push the warm surf ace l waters away and allow the cooler bottom waters to be brought to the surface, ~ Downwelling, when the onshore winds tend to pile up the ) warmer surface waters caut.;ing them to sink until the entire water colu=n beccces well-mixed, and Turbulence, when the wind-generated waves mix the surface and bottom waters. 2.2 STATION CHARACTERISTICS Pilgrin Station Units 1 and 2 are considered base-loaded, nuclear-powered electrical generatine units designed to produce l 655 mW and 1,100 mW of electrical energy, respectt.voly, under a full load conditions. The unPs are planned for an anticipated capacity factor of 80 percent. This represents operation of the i N units over a wide range of load conditions, such that the overall 5 capacity averages 80 percent. For the purpose of this 1 2-10 i

d:monstration, it is 6ccum?d that the ctation oporctos at 100 porcent lood c11 of tho time. The station withdraws cooling water from Cape Cod Bay via intake structures located south of Rocky Point in

Plymouth, Massachusetts.

The cooling water is returned to Cape Cod Bay via a diacharge channel which is designed to promote rapid dilution I of the heated effluent. The cooling water is used primarily to remove heat from the station condensers. Additionally, a small B quantity of heat is re:mved from the station service water 3 l systems. The cixculating water systems are shown schematically in Figure 2-15. The total heat rejection during full load operation of Pilgrim Station will be approxirately 1.34 x 1010 Btu / hour. This reflects operation of both Units 1 and 2. Unit 1 has a circulating water flow of 690 cfs at a tortperature rise of 300F and a service water flow of maximum 23 cf s at a maxi:tum temperature rich,of 150 Unit 2 wi.11 have a circulating water flow of 1,700 cfs at a imum temperaturo rise of 200F, and .a service water flow of 78 cfs at a maximum temperature rise of 100F. The combined flow will be 2,560 cfs at a temperature rise of 220F. Table 2-3 su:r narizes the contribution of each system. Under reduced load conditionr. the circulating water flow rates will not normally be reduced, except l for substantially r educed power levels over extended time periods. Table 2-4 pre sents anticipated, typical' opcrating characteristics over a range of possible load conditicns. Minor variations in flow and temperature rise will occur under various tidal conditions due to the hydraulic characteristics of the circulating water system. Table 2-5 presents approximate flows in temperatures for a range of tidal conditions. s The cooling water will be rapidly heated in the station condensers and will remain ut essentially constant temperature until discharged. The times at which the cooling water will be subject to increased temperature will vary between Units 1 and 2. [ Table 2-6 lists travel times through the cooling systems subsequent to heating. Units 1 and 2 will be capable of operating under transient -t conditions such as those associated with sta tion startup or shutdown. Unit 1

has, as part of its discharge permit, an I

allowable maximum discharge temperature transient of 150F per I hour which would not be exceeded except under abnormal operatin It is expected that a similar temperature transient conditions. i will apply for Unit 2. r 2.2.1 Discharge System Units 1 and 2 will utilize a common discharge channel to return cooling water to Cape Cod Bay. The circulating water will leave the discharge channel as a high velocity surface jet, and will

l rapidly mix with the surrounding sea water.

"tgures 2-16 and ] 2-11 l l an i

I I r .g*. .!.,~....3..,'* % e

• d I.,

.#( k,$[kkf4'Ocb , A$E;.'N'I:I' N ' CAPE C00 B AY (50'F, ' '. Mhu,jd6cing # 6fsp (h[ tklet ',' 'iQ)W,Q.G, ^l: %',",9-[# I. L hh.hk h)Nk ' f. k I k 9 Y. tf ' b@;b,$,'.:w$"?:)N- ~~ -~'- d \\.' 'ro"c ecYre ein sE%'i5% tM H g,o ep, tAh.Mffp).Y p.~.,r "if:<: ,j e '"'. 0AR RACK ,,4;Lgy N'g@p. ' *(,'.ro ^'690 sfs C6 c. Weter0fgh.ib,g.h.: fUM 4 1 R AVE LING C y e g'.' I., - SCREEf4 e, p 1, 73 cf service Weinw ::: e

• (,.

w'klILlll -.-.- m tu=a l n.v.y', I hk c.1770 t's. 78 ett r L'F 70't M S E R VIC E INTAKE WAten ,,,.4 p $TR UCT UR EG AngA I 3,.,.,4 6 I ~~ ~ UNIT 2 UNIT 1 ~~~~~l -~--- ~ "~ DISCH A RG E DISCH A RGE k ~ ~ STRUCTURE STRUCTURE e, _/s C '0,, UNIT 1 UNR 2 \\ o C l l 1 I c c c ~ 235' of 13' X 7' I -g 't C 80 A 6.$', e a t 15'@ 'I / NOTES; 1. Flows shown esturne Mt.W tice level and twomnit operating eond tions. 2. Denoten cop 1anser 3. 1ernperatures shown ensume intake wome tempoteture of SO'F and two urut ope eting condet ont 4.in,.eed; emete, I 3.e,, _e.. ... e _,..... ,o v, Frsuae 2-yg. g ... e,,s.. e.... CIRCULATING WATER SYSTEM SCHEMATIC 3I I ,I

I TAB 2 2-3 PILGRIN STATIO!1 COOLDiG WATER CHARACTERISTICS f (POLL LOAD) Tmrp Heat Flow Rise Rejection .Le f s ). .( of,L .LbtuWr) l Unit 1 Circulating Water 690 30 4.7 x 10' Service Water 23 15 7.8 x 107 l Total 713 30 4.8 x 10' W Unit 2 Circulating Water 1,770 20 0.0 x 10' 5 Service Water 78 10 1.8 x 105 5 Total 1,848 20 8.2 x 10' Units 1 and 2 Total 2,561 22 1.3 x tot 0 I I { TABLE 2-4 TYPICAL LOAD-DEPENDENT OPERATING CONDITIONS (UNITS 1 AND 2 COMBINED) I Temp. Heat j Load Flow Rino Rejeetion .i. f s ) (

• F).

,{ Btu /nr) ,,1).)_, c 100 2,561 22.0 1.30 x 1010 80 2,118 21.3 1.04 x 1010 60 2,118 16.0 0.78 x 1010 40 1,723 13.1 0.52 x 1010 20 1,723 6.6 0.26 x 1080 h 0 0 0 0 t I I }w I 1 of 1 I.i E

_ _ - _ - _. ~ _. _. I TABLE 2-5 DISCHARGE C2!APACIT.RISTICS FOR VARIOUS TIDAL CO!;DITIOliS Exit. Elevation Flow AT Velocity (P[L) ,,(cf n 1 (O P) { fpq)_ Ac!W (S) + 5.0 2,810 20.0 7.2 I MIIW + 4.3 2,810 20.0 8.1 MSL 0 2,710 21.0 12.4 MLW - 4.8 2,560 22.0 12.2 MLW (S) - 5.6 2,540 22.5 12.1 I I I TABLE 2-6 TRAVEL TIMES FROM CO!JDENSER D*LET TO CAPE CODE BAY (MDIUTES) Sealwell Mixing to Unit 1 Point I !Jomsl or>eration (Units l{,A Condenner Pim Mixing Pt. t.o Bay, Total Unit 1: T = 300F M11W (S) 0.1 1.0 2.2 1.7 5.0 MSL 0.1 1.0 2.0 1.4 4.5 MLW (S) O.1 1.0 2.0 1.5 4.6 i I .Jnit 2 T = 200F M11W (S) 0.1 2.0 0.4 1.7 4.0 MSL 0.1 2.1 0.4 1.4 3.8 MLW (S) 0.1 2.2 0.4 1.5 4.0 I I I I ~ I; ,a,

I I .,s f y l -5 s n EL ii ~ STA I m, 0 1 E L 11 $tA g E.1T.JJ E u s o _. __ ttT A ( W &

• C4

,a i g E L 15 A Et 17,, E L 18 l / l N h UNIT 7 /b 6 /" UNIT.1 = SE AL WELL SE AL WELL w __ NOTE: Einettons e,e M$L catum. PLAN I! E , !::::.::u D ; ;'.';:ti*r FIGURE 2-16, l DISCHARGE CHAtitiEL g

~ i 2-17 illustrate the disch arge channel geometry. The channel is e 20 feet and traperoidal in cross-sectio.. with a bottcru vidth c side slopes of 2:1 (H :V). The invert elevation runs level at elevation -4.8 MSL from the sea.1 wells to the point where the channel intersects the beach slope which it then follows. Table 2-5 presents flows, tc=peratures, and exit velocities for various tidal elevations. 2.2.2 Intake Systen The circulating water and service water drawn frca Cape Cod Bay will pass between breakwaters and through a dredged intake channel to the facility's intake structures. Figuxo 2-18 shows the intake structure for Unit 1. Figure 2-19 shows the intake structure for Unit 2. The Unit 1 screenwell contains two circulating water pumps having a capacity of about 360 cfs each. Water passes under the skimmer wall whose botten is at -12 feet P.SL at the f ront of the intake structure. The skirrr.er wall is designed to prevent the entrance of floathg debris. Intake water passes through trash racks designed to intercept debris of large si::e, 3 inches or

greater, and then flows through traveling water screens which remove debris, 3/8 inch and larger.

There are two tra.veling water screens for each of the circulating water pumps. The intake structure is divided into three

bays, one for each of the circulating water p, umps, and one for the five service water pumps.

m condenser tubes on Unit 1 can be cleaned by back-flushing. This g is accomplished by operating a single circulating, water

pump, closing the discharge valves at each outlet water box, and operating the crossover valve connecting the discharge water boxes.

Circulating water will flow naturally through one side of the condenser, cross over, and flow in the reverse direction through the other

side, and discharge back to the intake structure through the idle circulating water pump.

The Unit 2 screenwell contains four circulating water pumps having a capacity of about 425 cfs each. Water passes under a skimmer

wall, whose bottom is at -8 feet P.SL, and then passes through trash racks.

Water then passes through traveling water screens. Walls between the traveling screens are provided with openings flush with the f ace of the screens, thereby providing a continuous path for lateral novement of fish over the entire vidth of the structure. Openings leading from intake structure I to the intake bay are provided at both ends of the structure. A back-flushing capability is present in the Unit 2 circulating I water system design. The four circulating water pumps are manifolded into pairs of pipe lines that convey cooling water to alternate tube bundles of a 3-shell condenser. The two pumps serving a single line can be shut down, and valves are positioned 2-12 I i

l I I a a. a c t S EL11 f f E.6 INVERT / \\ EL ~4.8 17, O W;O_ - ^O n Ou,,.,,%, BREAK IN SLOPE I L^-~ ~~ 40 LONGITUDINAL SECTION l LOOKING WEST I I z g to' I i ,, 9 t CROSS SECYlON SE AWARD END g' uorE, smoo~.,. vst..... in::::.:::!EI;:::'.';::*: F!GURE 2-17, l ~ I-DISCHARGE CHANNEL PROFILE AND CROSS-SECTION 1 ) = B

_..m m l w*h u, g A v~ l E '-- ehmgl-m$.j

s N w 1

g w g Sd j is %rwlg l 2 3 a-. l' ~ [J I T 3.,,,, _ ... - + -, % ) 7. .) - ] \\,%, f Asy - I s xl.(.,._., j}, t u%t,: i i 's Q v ." y.

• aA fg 1 I

-.. td >y C .A f.- M1 ll l9 *p- ,) l I r (f pr[. J w, g J. ' l,l._ :r r, -( r,-.,. g .q r .J ' g p. g... w vi je Q/'"' G: a M-s- ( l1,. j' 13 e j I i } 1-4 I 4 !i 5 x d-7 l s e w <.3p. y.. l 1 a b.[h !! ' l.YM !-. ], l e k l:.e::1,"y.r .I,.mq , i!'n t l =.,r,n!oh,IMr e a ..e,

.. L,.

il g;c. ga i ~-huj]I n l.9, k tA fia,k ; O'd(! cu 1 p ~-[. ) ( '-- -1 r$e.ll i

i *:-yI c g iQ L # % 'r,'.::.g, l

&- " l i R1 L W ;,--4_ _. 4 i f. b } ::. i,=:; l4.N7( - Swy. etl 1f- $t7nL C,'.c gs 4 e = a v)rd: 73 e{ n Ca J-A 5 4 t 2 .i if I 'I F , _.2 n=6? e ~* .,y p3gr\\p. ^ I 5l 4 !ly fg. !t ' sm . ~:. q l -l....y y!p r, - Y ,,9 e.. p!: j 9 5 p59 b p:: , g e' a i e... >,.. i.... _. _.... Wn,j ici ,Q g_. . #,,1 1;9 ib a_E t I ^ .f d ?. l{$=.-E::.:r. i) &5 I. t I ji e I.. 1 I I I I 1 I

in. A " =eas a 4I ill 5 / w a )u .+\\ .g I w n' % '1 \\ 9s 3, 3'- um a ' 92%mblb El l 92 i Eliadd a5 \\ - 92 \\ //Z57 l // 1 // \\\\l i .../ \\ 4, l l' 1 i .. l. ,. i t c. A> E N ti g x '~~. t IL 11.... Wp Wi) }Y:!; h3: t!! V ilhW55 oi l T c [,L. i g 2 = % = v- _.g j'u%.:h.!! 1 N: iikg li % ;pi rJ-l I',j)4 _L piiWej l o e [ lI I ~ !.44._ bq

._d.j[A ;zpd 5

4 a + i i !n-ys 4: iL / I } v "; = e/ I I )!I k 2.s .e .r. 5 y,.- - s,,4 _..', x... .s /3M..illd.,e, ,3 .4 .....a t, r c !gh_.;.2...jilM J(l._!!'m ! i l j 3 >, . _7,, ;i..5,7g,,0....;=... D : .y s - i j g. cc, ing_ t. =y 3, t q,, jig.l7 3. 1 til i.l m ~ I. . j'g li !-c "J. g I g g sa ll

1 )

t Il E R5 T n j j! l r, t II M 5 .6

to permit a portion of the circulating water to return into the intake structure in a manner similar to that used with Unit 1. It is presently intended that mussels be controlled by ba ckwashing. Basef on limited Unit 1 erperience, mussels are controlled by subjec*ing them to temperatures in the range of 100 'I to 1100F for one to two hours at intervals of two or three weeks t when bay water temperature is above 4So? (approximately 225 days per year). This proposed schedule may require ad justment based I upon future Unit 1 experience. When back-flushing is necessary during periods of peak amba.ent temperatures, it is possible that the average temperature of the mixed 2-unit discharge flow will -l be as high as 950F for periods of about two hours or-less. The number of such peak discharge temperature occurrences is not expected to exceed twelve per year (approximately three I occurrences per year for e v. a of the two pairs of Unit 2 circulating purps, and two "

circulating purps).

Table 2-7 presents circulat 'ater intake velocities at various 1.ositions for toth Unit 1 c. it 2 screenwellu. ,7 2.2.3 Plume Characteristics A number of e:<parimental and analytical progra.s have been perf ormed to study the thermal of f ects of Pilgrim S tation. The I experimental work performed to date consists of field curveys to document ef fects occurring during Unit 1 operation. A dye study performed in De cember,

1972, by

Vast, Inc.,

of Ivorytown, I Connecticut, obtained data on the circulats.on of the themal plume and mear.ured the vertical d.ictribution of the discharge n flow. An infra. red aeriil survey by Coastal Research Corporation, E of Lincoln, Massachusetts, also performed in Dece:aber, 1972, collected imagery yielding synoptic views of the overall extent of the surface component of the thermal plume. Temperature surveys conducted on a number of dates throughout

1973, by the Ralph M. Pa.rsons laboratory for Water Resources and Hydrofynaries of Massachusetts Institute of Trchnology, collected horizontal and vertical plume te=peratures over a

range of tidal and climatic conditions. A second in.frared aerial survey condveted by /,oro-Marine Surveys of New London, Connecticut, in August I 1973, obtained additional synoptic iragery of the surf ace extent of the the =al plume. A temperature surtey conducted concurrently by Marine Resources, In c., of East

Wareham, Massachusetts, collected vertical temperature profiles.

Results of the field studies demonstrate that the shape of the 'g themal picme produced at Pilgrim Station is highly dependent 3 upon wind-induced and tidal currents. While tidal conditions, being cyclic in nature, would tend to produce periodic swings in g the orientation of the the=al plume, wind ef fects in general are, unsteady and variable. This contributes to the the =al plume l'g having a shape a :d position which is constantly changing with time in an unsteady or noneyclic manner. 2-13 =--

TABLE 2-7 Ib" FAKE WATER VELOCrrIES Average Low Average High Astronomical Astrono:aical Tide Tide (-7.1 MSL) MSL ( + 6. 9 hS L) i thit 1: g )l Approaching Intake m Structure 0.0 0.56 0.44 l Under Skirner Wall 1.I 1.1 1.1 Approaching Screens 1.0 0.7 0.56 4 Through Screens 2.0 1.4 1.1 E Unit 2: W Approachire Intake j Structure 0.8 0.6 0.4 M l Under Ski::ner l 1 Wall 1 1 1 Approaching Screens 1 0.7 0.5 Through Screens 2.0 1.4 1.0 I, i I l I I I I I I t 1 I 1 of 1 ') E

J In addition to shape and direction, the data also show that the 's-areal extent of the pPme is highly transient in nature. This is a result'of the unsteady nature of ambient hay water te:rperatures and meteorological conditions, toth of which govern the rate of I-heat exchange between the thermal plume and its surroundings. Under conditione during which the station heat discharge has been maintained at essentially constant value, the areas within plume isothern.s have been observed to vary significantly. i Figure 2-20 illustrates an isothermal map of the Unit 1 thermal t plume obtained frcra an infrared aerial survey. l To d a t.c, there is no analytical tool which permits the accurate g predizion of nonsteady-state thermal plume behavior. Work is .3 proceeding to develop such a tool for Pilgrim at this time, and as this j it-is antici. pated that valuable information will result program proceeds. At present, two steady-state predictive ;nodels have been used to correlate the Unit 1 thermal field data, and to estimate the combined Unit 1 and Unit 2 plume extents. These are the Stol:enbach-Harleman (S-H) model and the Pritchard mdel. I The S-H model is a three -dimensional, semi-analytical, near-field model. The M itchard model is an empirical model which is I applicable to predictions over the entire field. The S-H and Pritchard models ure used to estimate plume

l characteristics due to operation of Units 1 and 2

at Pilgrim Station. The results of the model are shown in Figures 2-21 I through 2-24 and in Table 2--8. The figures present center]ine temperature profiles and cross-sectional temperature g distributions for both high tide and low tide conditions. 3 Table 2-8 presents plume surface areas for both high tide and low tide conditions. The approximate extent of the area which could be subjected to thexmal effects under different conditions of wind and tide is shown in-Figure 2-29. This figure was derived by extrapolating the hydrothermal field survey results for operation of Unit 1, as follows. It u observed that the maximum distance au which increased te_~.pez.ture ettributable to operation of the station could be normuly identified is about 6,000 feet from the discharge point. This corresponds roughly to a temperature rise l of about 10F. Given that the total heat rejection due to Units 1 - l and 2 combined will be about three times that of Unit 1

alone,

.E and asstraing that the thermal plume with both units operating will be geometrically similar to that associated with Unit 1, but 1 g with three ti:c, the surf ace area, it is assumed here that the 3 maximum far field plume extent will be increased proportionally to the square root of 3, or 1.73. This results.2.n the estimte 's of the ocean surface area wlich would be subjected to having a g detectable temperature increase an extent of approximately 2 miles, as shown in Figure 2-25, ~ I

h o e \\ E 1 e a ,3-g n w s /* y / 8 ?. y n 'T ep ,/ r / r 1 I / t 1. ~ N: ( 5 2 -i 11 .l a e Ch *N r 32$5I 5 33 I r o I x \\ l \\, \\ N l \\ l (s \\ l i l i i az I \\ l / 3: f 1 ksjl \\(m\\; n LJ 'T gi c *dJ 13 g g\\'t Nh t i '. '['Q :) ~g/I n}} = ;a=[/ l [d5. ;'- 2, i , m.m 1 M

f 3 1I iI l I I to o I. 8 2 w w f 6 4 ~ -k h 4 6 2 8 I ~ g H u, 0" 10 A G g 2 12 4 14 3 m y 6 p 16 y f 8 18 L 10 20 W G 12 b 22

c o

24 rr s 24 S C 16 2'F 26 18 28 W 20 30 n 32 24 - 34 l l 1 l I I I l l l I l I 0 1 2 3 4 5 6 7 a s to 11 12 13 14 15 ? DISTANCE FROM END OF CHANNE L - FT X 10'2 i <l

.:::it*:.;='.';;!:

FIGURE 2-21 PREDICTED VERTICAL EXCESS TEMPERATURE i PROFILES ALONG PLUME CENTERLINE - UNITS 1 AND 2 - HIGH TIDE I !o I

I I I 1o - 0 u. 2 0, _-- 2 A T 15'F M" 3 T.10*F > - 6 4 2 8 D 10 i p 7 w 12 j, 2 - 7 3 3

1. j 14

} y .4 k6 ,d

• 16 w

c. 'S 8 4, 20 j 10 )a c w' - 22 {.12 m $ 14 24 c., u 26 0 16 d 28 1B 20 30 02 22 24 34 l l 1 l 1 l l i l l I I I I I I I I 10 9 8 7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 8 9 to DISTANCE FROM PLUME CENTERLINE FT X 10 tu I p:=::!t :.m:'.':::11 FIGURE 2-22. I PREDICTED VERTICAL EXCESS TEMPEPATURE PROFILESATMAXIMUMPLUMEWlDTH(TYPICAL - UNITS 1 AND 2 - HIGH TIDE I I I

4 .I i 1I 'l l AT = 15'/ F 8 o 4 l 4 0 N e 'I )% *v n 12 i 8 AT = 20'F AT - t o*F 16 . 12 E 5 2o J g$$ 3,. o g 8 25 l 5 2o AT 2'F d I . E 24 \\- 23 c r, e 0 28 22 g as 1: u 40 36 i-u I I I I I I I I I I I I I I o i 2 3 4 s s 7 8 e io is 12 is 14 is Ul:!:.l:l!I;*;'/.';:ll*j O! STANCE FROM END OF CHANNEL FT X 10'2 FIGURE 2-23, l PREDICTED VERTICAL EXCESS TEMPERATURE PROFILES ALONG PLUME CENTERLINE - UNITS 1 AND 2 - LOW TIDE. I 1I I

l 4 8 J 0 4 J, V 4 a 4 4 o = i 7 i M p 4 , r e p e e 5a A r. 2o r U ~gHi I lE O [ O 32 A T IS'F j Lu g ig ~' M -16 AT-10*F p us g 4 g g .2o \\ 24 g x 23 b ^ [ -24 g uso n L-y as 22 1 40 -36 i f 44 j 40 1 I I I I I I I I I I I I I I I I I I I I 10 9 8 1 6 5 4 3 2 1 O 1 2 3 4 5 6 7 8 9 10 l l II* E-. Y1} l DIST ANCE FROM PLUME CENTERLINE FT X 10-8 AIU'" 7 ( FIGURE 2-211. PREDICTED VERTICAL EXC(SS TEMPERATURE PROFILES AT MAXIMUM PLUME WIDTil (TYPICAL / - UtilTS -1 AND 2 - LOW TIDE MI M M M m M m M M M M m m m m m 4

g-a mr g - g-i~~~ TAILLE 2-C PREDICTED StELTACE AREAS WI11 TIN VARIO11S EXCESS T1MPER AMJRE IIDTIIERPls (Full Power Operation of Units 1 and 2) Area 1:r.clo sed try Excess Temierature Isotherm ' (Acres) 143w Ti d. - liigh Tide Ttsperature Mise Pritchard t k'.lel S-ti tsxtel 3Yitclear<1 t*xiel S-tt Pkw1451 Alove Ambient [*P) No Itecire. 10% Itecire. tk> Deci re. th> Inv i re. 101 Decire. Ito Recire. 20 0.1 0.1 0.2 0.2 1 15 0.2 0.2 1 0.9 0.6 3 to 0.6 0.7 3 2 3 11 5 6 8 23 31 47 3 23 33 + 101 1 '* 7 2 57 03 233 363 Associated IIal f-Deptje of Thermal Plume (it) 26 26 21 21

• Not Computtd 1 of 1

4 do. [ t ir l \\ DUXBURY lt BAY CA PE COO BAY i l PLYMOUTH bAX M DET j SURFACE PLUME EXTENT g THERMAL ITiPICAh'D lE \\ / PILGR:M ST ATION e o l t' s I $ CALC.MUDCR MMS t l FIGURE 2-a ASSUMED APPROXIMATE EXTENT OF THERMAL EFFECTS A E

1 I While the thermal plume would not occupy all of this area at any one time, the figure does indicate the extent of the region in which the thermal plume would be located. An approximate area of bay bottom which will be subject to direct 3 contact by the thermal plume is shown in Figure 2-26. This 3 figure was derived from the centerline plume temperature profiles shown in Figures 2-21 and t-23. It was assumed that the 3 distances along the bottom at which elevated temperatures would E extend yould remhin ccnstant regardless of direction. This results in semicircular profiles in that it probably substantially overestimates the size of the affected areas. Because of the morentum of the discharge flow and the jet-induced entrainment flow which will occur along the sides of the discharge jet, it is unlikely that areas along the coast adjacent I to the plume will be af fected as rauch as shown. This

figure, however, is useful for perforiring a conservative prediction of

) the maximum thermal af f ect on benthic organisms, and will be discussed in Section 6. I I i i >f s I ~ >I I I I I I s

Ch' 'R d R n 2 - /o s [3 \\

1. 1. '[,[##

20 ff PILGRIM STATION E t-I ? ,,5?U D,oo 290 i j SCAL.E-FEET i I FIGURE 2-25 i ASSUMED THERMAL PLUME j BOTTOM ISOTHERMS (*F) E

a- ,n SECTION 3 DESCRIPTION OF AQUATIC COFMUNITIES

3.1 INTRODUCTION

5 The aquatic biota of Cape Cod Bay is typical of that found in marine environments of north temperate climates. The biotic Ig communities are diverse assemblages nere representative of a E marine than an estuarine environment. Cape Cod Bay is a diverse marine environment for several reasons, including the following: (1) A wide variety of environmental conditions are encountered, including an extensive range of substrate conditions. For example, temperatures in shallow water can range from below 00C (winter) to 200C (late summer). 5 (2) Cape Cod Bay is an area of =cogeographic overlap, and

)

various northern species reach the southern extension of their ranges in this area. An even greater number of I southern species range no further north than Cape Cod. The overlap of these :cogeographical types results in increased species diversity for the area. Uinter temperatures are si:rilar in waters north and south of Cape Cod Bay; however, temperatures are significantly different during the su=mer months. %%ile adults of certain species may survive a Fwide range of temperatures, temperature limits become very important during the reproductive periods. This is often more -important in limiting species distribution. Adult stages of a southern species may survive all year in the bay, but su==er temperatures may not be warm enough to initiate breeding. Northern species may not be capable of surviving the warmer temperatures south of the bay. Geographical distribution based on te=perature is discussed by Hutchins (1947). 3 Allee (1922) showed that of 241 littoral animals recorded in this

region, 50 percent were not found north of Cape

Cod, and 11 percent were not found south.

3ousfield (1973) lists 85 southern species of amphipods in the New England area; 46 of these do not extend north of the bay. Fifteen of the 34 northern species do not extend south of the bay. 3.2 BENTHIC COMMUNITY The rarine environment of the Manomet area near Pilgrim Station is characterired by two kinds of substrate, hard rock and sand. Each has its own particular flora and invertebrate fauna. Algae I dominate the rocky areas. Most of the animals found there are associated with or are directly dependent upon these algae. The sandy substrate might be further divided into clean inshore sands ,i 3-1 'I

I and silty sands of the offshore region. The transition, however, is gradual, and many species distributions overlap the two g conditions. 3 3.2.1 Macrophytes Ascochvilum is the dominant intertidal macrophyte at Rocky Point and Mano=et Beach; Fucus is dominant intertidally at White Horse Beach (Figure 3-1), Distribution of these species appears to be closely related to substrate types in this area (Boney, 1966). I _As cochvilum is nere prevalent in rocky areas and Fucus in areas of small stones or rubble, i Irish moss (_Chondrus criscus) is a dominant subtidal macrophyte species in Cape Cod Bay and is the chief component of the g subtidal flora near Pilgrim Station (Figure 3-1). Depending on E }

depth, Chondrus covers up to 90 percent of the available substrate.

Chondrus attains a maximum density between mean low water and 14 feet below mean low water. At depths greater than 'i 10 feet below mean low

water, Chondrus density decreases and Phyllochora (P.

brodiaei and P. membranifolia) becomes the dominant macrophyte. Laminaria sp., Corrallina officinalis, i Polvdesrotundus, and Lithothamnion sp., are the remaining conspicuous representatives of the subtidal algal flora. 3.2.2 Benthic Invertebrates Mvtilus edulis, the blue mussel, is the dominant animal found in Es rocky areas in the immediate vicinity of the station. It is 3 present throughout the yecr and at all depths studied (intertidal to 30 feet). Three other mollusks are ubiquitous and abundant: Littorina

littorea, Lacuna vincta, and M diolus,modiolus.

Both j Littorina littorea and _L_acuna vincta are abundant intertidally ) and to depths of 30 ieet, and are typically associated with benthic macrophytes. The echinoderms Stronevlocentrotus droebachiensis, Ochicoholis aculeata, Henricia sancuinolenta, and Asterias sp. are also present. Encr usting and epiphytic forms are abundant on the rocks and algae where sponges such as Halichondria sp., Haliclona sp., barnacles (3alanus balanoides), and bryozoa (Dendrobeania murravana, Electra sp., and Crisia eburnea) can be found. The algae provide habitats for a variety of filter

feeders, g

herbivores, carnivores, and scavengers. Con =en among these are the isopods Idotea daltica, Idotea choschorea, various ganmaarids 3 and caprellid amphipods, and the polychaetes, Soirorbi spirorbis_, Nereis Delacica, and carnivorous phyllodocids. The dominant offshore species in rocky areas is the American lobster (Homa rus americanus), which inhabits rocky bottom substrates from the shallow subtidal zones offshore to depths in cxcess of 1,000 feet. Lobsters inhabit the ledges off Rocky 3-2

f i. 6 CAPE COD BAY \\ s-s [. [."' * *'.'h I?. k ;,

$.h. h'.~.~

..;-::**a ~- ' ',' ' %*}. *: W ' C * -!'-l.'... . /j. -:.,." T.y. is'.'.. s$0??Mr. .'"g?'g,, K ' f.;

• ', *. d::fh[i.h.

'[*, d a.'. ~ybb '\\ i&,)..;.-: [g. -P

1.,,

4 ~.".'4,' y$.' ';.'; ' i? A r F00T CONTOUR tutw ' ~,,,,e' *'-d. '; ~' ' *6, i, Ic ',' i.,..:Q[ p:::?:.p.. .~ t 9;.' ..4.:&:,. '. = *'sq;U): ' ' am .,. ;.T, h,'i..:'.. WATE M FOOT CoreTOUft tu

• MLWAET PT.

Pji'.?.., -< *, T ..E', ;M.,',>ff iy>:'.: g\\ [' -[ I,. ', '/* '- 7 'f. Gh

• 4 s, ;

Ng N$!,!khg; * !b N ** 3.egp3yWME*'* i ~k 4 C ROCK 1PT l

NEi?[*

I M O ,. '{. l s

c. 6*d.'1 '

PILGR M STATION ',*f:' ) i- .jh' b l .:4. ' s l ,y l Za,* i?I n.,$ M LLGENO 0 6000 2000

• 000 4000

'XX4 A ' 8 MtLE P\\';M;\\\\\\NJ MYTituS-'XAi FUCUS CCMPLEh SCALL fiti DS l5j 9, - yj CHONDRUS CRtSPUS ASCOPHTLLUM .. l LITTORINA COMPLEX f WYTILUS-l r r.unt s-s AQUATIC COMUJNITIES IN l VICINITY OF P GRIM STATION 1 I ] l i 7

1 .I I. Point and White Horse Beach, which bracket Pilgrim Station, and of f Manomet Point f arther to the southeast. gl E, The sand envirorrtent shows a gradual transition of clean sands, in which haustorid amphipods are

dominant, to offshore silty

sands, and the most abundant animals are deposit-feeding

'l polychaetes and bivalves. Acanthohausterius millsi and i' Protohaustorius deichmannae are the dominant species in the clean i sands. Edotea triloba is also very com: ton inshore as is the bivalve Tellina agilis. Four other species typical of t.he ) inshore co:=r: unity are Echinarchnius

carma_,

Nechtvs

bucera, Soisula solidissima, and Lunatia heros.

~ I The offshore co=mity is characterized by a variety of deposit-feeding bivalves and polychaet.as, including Nucula

annulata, N.

g _delchinodonta, Ninoe

nierices, E chone

incolor, and _A_r,,g ei d e a 3

1 ie t f rev s_i. 3.3 P NiKTON CO M.ni1TY N [ 3.3.1 Phytoplankton f The species composition and abundance of phytoplankton in Cape j Cod Bay can be expected to vary throughout the year. Temperature, nutrient availability, and wind are major-factors af fecting the seasonal changes in plankton. C. ape Cord Bay is characterized by a diverse phytoplankton community typical of an .l unpolluted coastal area. l A total of 42 species of phytoplankton were identified from water I samples collected in the vicinity of Pilgrim Station in September g 1971. Diatoms were the most abundant group and had the highest g t biomass. Abundant diato species included Lectoevlindricus j

minimus, Rhizoselenia delicatula, and Cvelotella nana.

The phytoplankton comanity also contained _Rhodomonas amohroxeia, a chrysophyte flagellate, and Tetraselmis sp., a green alga. These 1 five species comprised 80 percent of the total phytoplankton cell count. A subsecuent study from \\ugust 1973, through December l 1974, observed seasonal variation not addressed in the 1971 i study. The diatom Skeletonema _costatum and Lectoevlindricus minimus were dominant during much of the sampling period. 3 Skeletonema density increased in the fall,'while Lectoevlindricus B density increased in late winter. Other dominant species l included Lectoevlindricus

danicus, Thalassiosira sp.,

and g l-Cheatoceros sp. In

general, this study indicated different g

i dominant algal species from the 1971 study as a result of seasonal changes. I I 3-3 as

3.3.2 "ooplankton Samples collected in 1970 ud 1971 from Cape Cod Eay in the vicinity of Pilgrim Station indicated a sparse

ooplankton co:= unity in winter.

"ooplankton densities increase during the sunner months. The :ooplankton community was strongly dominated by copepods. Centronaces tyoicus was the rest abundant winter I species. Pseudocalanus eloncatus, Temora loncicornus, and Acartia clausi were collected throughout the year. Acartia tonsa was unaccountably absent during su:=er. In a study from August

1973, through December 1974, the dominant species were Acartia I

clausi, oithona similis, Pseudocalanus ninutus, Acartia tonsa (in sur=e r), and Centroraces tyricus. The species in this study g follow closely those reported for the area by Anraku (1964). g These species are representative of the Pilgrim site and are typical of estuaries and coastal marine species found in temperate climates characteristic of Capa Cod Bay. 3.3.3 Meroplankton From March 1970 to December 1971, eggs and larvae of 25 species of fish were collected in the vicinity of Pilgrin Station. Atlantic cod, pollock, winter flaunder, cunner, tautog, squirrel of I hake, Atlantic mackerel, and silver hake comprised 96 percent the eggs and 68 percent of the larvae collected. In collections in 1972, cunner eggs were abundant from May through

August, and larvae were abundant frac June through August.

Winter flounder I eggs and larvae were present in April and May. Menhaden eggs were collected in

June, while larvae were collected from June through September.

Pollock eggs occurred from October to I

December, and larvae were collected in December.

Cod eggs appeared from October to May, while the larvae appeared from November through May. Ichthyoplankton collections in 1974 generally indicated the same seasonality. Labrid eggs (cunner and tautog) were extremely abundant in mid-and late su:=er. Developing larvae were pr h ily cunner and, therefore, eggs were thought to be cunner. Gadid eggs (both pollock and cod) again became abundant in mid-November through December. Pollock larvae also appeared in December samples in which they were abundant. Sivalve and polychaete larvae were the most abundant larval invertebrates collected. Mvtilus edulis veliger larvae were abundant in late st==er and early fall of 1974 in the vicinity of the Pilgrim Station. Other bivalve larvae were collected periodically throughout the year. !bst fish and invertebrate eggs and larvae collected in the vicinity of Pilgrim Station are indigenous to the area or at least to the Gulf of Maine regien. An extensive cod-spawning ground southeast of the station has been described (Bigelow and Schroeder, 1953). The spawning areas of other fish species in Cape Cod Eay have not been documented. v 3-4

The eggs and larvae of most species were presumably carried into the region by water currents. 3.4 FISH COMMUNITY Approximately 50 fish species have been identified in the vicinity of Pilgrim Station during monitoring collections from / 1969 through 1974 This monitoring program includes both trawl and gill net collections. l Trawling was conducted at three of fshore stations in the vicinity of Pilgrim Station. These stations are representative of the benthic fish com unity of the silty-sand substrate. The most abundant species in trawl catches were winter flounder (Pseudocleuronectes americanus), yellowtail flounder (LdJnanda f errucine a), windowpane ilounder (Scochthalmus acuosus), oceanpout (Macrozoarces americanu s), longhorn sculpin (Myoxocechalus octode cemscinosus), and skates (3a ia spp.). Winter flounder were present in most trawl saxples. They were E nost abundant in late summer and early f all, and least abundant 5 8 in mid-winter. Yellowtail

flounder, windo.rpane

flounder, longhorn sculpin, and skates have been collected in small numbers throughout most of each of the study years.

Comparisons of the J trawl data accumulated from June 1969, to December 1972, indicate

1 that both the species and relative abundance at all collecting stations were similar, indicating a relatively stable community.

f Gill nets were used to collect both open water fish species and species associated with rocky substrates. Pollock (Pollachius virens), alewives (Alosa p_s,eudohareneus), cunner (Tautecolabrus f adsoersus), and sea herring (cluoea hareneus) were the most abundantly collected species. Pollock, Atlantic cod, cunner, and alewife were common during May and June collections. Pollock and cod abundance also increased from October through December of each year. Sea herring and smelt (osmerju mordax) occurred in g greatest abundance in April, while numbcrs of cunner were evenly 3 distributed froa Pay through November. p The results of two sportfish creel censuses conducted by Mass. Div. of Marine Facilities at Pilgrim Station indicate generally similar seasonal trends in fish species composition as gill net l and trawl collec cions. Winter

flounder, however, were most abundant in the sport fishing catch in cpring and early summer, which may indicate that they are inshore and, thus, available to shore fishermen during this time.

In addition, bluefish were more abundant in the sportfish catch in late summer than in gill i net collections. I I 3-5

3.5 REFERENCES

- SECTION 3 j

Allee, W.C.,

1922. The Ef fect of Te:nperature' in Liriting the 4F Geographical Range of Invertebrates of the Woods Hole Littoral. Anat. Rec. 23:111.

Anraku, M.,

1964. Influence of the Cape Cod Canal on the Eydrography and on the Copepods in Eu: ards Bay and in Cape Cod

Lay, Massachosetts, Hydrography and Distribution of Capepods.

I Li:nnol. Oceanogr. 9:4 6-60.

Bigelow, H.B.,

and Schroeder, H.C., 1953. Fishes of the Gulf of Mhine, U. S. Fish had Wildlife Service Bulletin 53, 555 pp. Lo us efield, E.L., 1973. The shallow Water Ga:=aridean Amphipods of New England, Cornell University Press, Ithica, N.Y.

Eutchins, L.W.,

1947. The Basis for Te:perature Zonation in Geographical Distribution. Ecol. Mon. 5(17):325-335. I ~' I -./ !I I I 3-6

SECTION 4 REPRESENTATIVE SPECIES AND EATIONALE The aquatic biota of Cape Cod Bay is typical of that found in r,arine environments of north temperate climates. The biotic communities are more representative of a marine than an estuarino environment. Thus, the concerns of P'1 grim Station are not i sirilar to the concerns of onshore facilities in estuaries, e.g., I impact on spawning and nursery areas. 4.1 EATICSALE FOR SPECIES SELECTION Representative species exhibiting both nearfield and farfield effects were selected for detai'ed anaJysis. The choice of these .l species is based on species affected by Unit 1 operation, or potentially af f ected by the operation of Units 1 and 2. In most g

cases, these species are dominant,

either numerically or in g biomass, which reflects importance in the biological co,munity. Many of these species are of commercial or recreational interest; however, their selection was also based on their ecological imporsance to their respective com:minities. 4.1.1 Eare and Endangered Species l There are no rere and endangered species in the vicinity of Pilgrin Station. 5 4.1.2 Commercially and Recreationally Important Species There are two ma-jor commercial species in the irmediate vicinity g of Pilgrim Station - the American lobster (Homarus americanus) and a red

alga, Irish moss (Chondrus criscus).

A commercial 4 fishery also exists for winter flounder (P_sendocleuronectes amerier.nus) and Atlemtic menhaden (Brevoortia tvrannus) f (Table 4-1). Sport fish in the area include flounder, cod (Gadus norhua), tautog (Tautoca onitis), cunner (Tautocolttbura adseersus), striped bass (Morone saratalis), mackerel (Scomber l scombm s), pollock (Pollachius virens), and bluefich (Pomatomu s saltatrix) (Table 4-2). i 4.1.3 Dominant Species Species of phytoplankton and zooplankton will not be used as representa; +/e species in this demonstration for several reasons. Natural ecosystems experience wide fluctuations in population size and biomass of organisms of lower trophic

levels, such as phytoplankton and zooplankton.

These fluctuations are due to several intera cting

factors, includir.J density-depend ent mechanisms such as selective or nonselective predation and densitv-independent meenanisms such as daily or seasonal changes

~ in physical conditions. These fluctuations severely restrict 4-1 I E

TABLE 4-1 ESTIMATED COW 4ERCIAL CATCH OR HARVEST (lbs) IN THE VICINITY OF PILGRIM STATION Species Date LobsterC3) Irish Moss (2) Menhaden (2) Winter Flounder (3) 1970 782,518 375,000 968,000 1971 881,279 375,000 6,312,000 1972 871,485 473,000 11,920,000 1,425 1973 732,866 159,000 43,173,000 3,980* 1974 794,017* 265,000 47,032,000 7,498* (1) Harvest between Rocky Point and Manomet Point reported in j 5 Environmental Report (2) Total catch reported for the State of Massachusetts to [l National Marine Fisheries Service (a) Total com:nerical catch reported for Plyrouth County, I Massachusetts, by National Marine Fisheries Service

• Incomplete monthly totals I

I I I 1 of 1 l

TABLE 4-2 SPORT FISHING CATCH AT PILGRIM STATION g (TOTAL NUMBER OF FISH) g (1973 - 1974) 1973(1) 1974(2) Tomcod 13 7 l Atlantic cod 59 139 Mackerel 51 2 Flounder 37 232 I Pollock 588 440 Tautog 69 28 Cunner 82 1,294 Striped Bass 648 39 Bluefish 634 760 1,176 " Snapper" Bluefish 6 Ocean Pont j American Eel 4 2 Scup ', l (1 ) Survey conducted f rom Ju].y through November. (2) Survey conducted from April through November. I I I i g , ef,

their use fullness in assessment of impact from minor perturbations.

Secondly, short life cycles and indications of b

rapid regeneration of most planktonic organisms reduce power station impact on this component of the ecosystem when compared o [ to longer-lived species.

Thirdly, power station induced nortality of lower trophic level organisms does not prohibit their contribution to the ecosystem as sources of nutrients in detritus.

Dominant benthic species f ound in the W.cinity of Pilgrim Station include the brown highe Fucus and,Ascochv11um intertidally, and the red algae, Chondrus criscus, and Phv11ochora sp. r.ubtidally l (USAEC, 1974). The dominant iauna include the mussel Q1tilus) I and periwinkle Gittorina) intertidally, and the lobster and amphipod (f.canthchaustorius) subtidally. Senthic species should not be affected by the operation of Pilgrim Station beyond the I immediate discharge area, due to the bo"yant nature of the surface discharge. Primarily, benthic species with entrainable planktonic life stages would M

affected, since many benthic I

adu.lts are sessile or have limited robility. Intertidal spacies may be affected by nearfield effects, but studies to date have not indicated a measurable impact. Furthermore, intertidal organisms are tolerant of mny environmental perturbations (Kinne, 1970 ; lbn 'y, 1966; and Green,1971). [ Dominant fish species collected near Pilgrim Station in 1974 5 include winter flounder (collected by trawls) and the pelagic

species, pollock, sea herring, cun-cr, and alewife (collected by gill nets) - USAIC (1974).

The density of clupeid species l (alewife and sea herring) varied seasonally and annually (1971-1973), while the percentage co=oositions of resident species were more stable from year to year.

Clupeids, silversides, and rainbow smelt (Osmerus mordax) were the most numerously impinged fish in 1973, anc when the station was operating in 1974.

Labrid eggs and larvae (primarily cunner) and winter flounder larvae were the predominant ichthyoplankton taxa entraine-d as observed by studies frca January to December 1974. 4.1.4 Nuisance Species Two nuisance species have been identified in the vicinity of Pilgrim Station. The sea urchin (Stroncvlocentrotus I drobachiensis) is present in the vicinity of the station. However, its presence does not appear to be a result of station operation, since its habitat is not related to the discharge area. This species is of commercial concern to the Irish moss population as a predator. The sea urchin, however, is a nonselective predator and, thus, represents the same harard to all macrophytes. 4-2 {. i

Recently, concern has been voiced over nutrient-enriched, hented E

water from power stations causing an increase in red tide 5 abund ance. Prakash (1967) found that salinity is a more important ecological f actor than temperature in controlling the summer abundance of red tide (Gonvaulax 3amarensis). Analysis of the species composition and abundance of phytoplankton collected from Pilgrim Station intake and discharge has not revealed any increase in Gonyaula.3 sp. 4.2 REPRESENTATIVE SPECIES LIST AND P.ATIONALE 4.2.1 Irish Moss (Chondrus crisons) (Figure 4-la) Irish mo ss. is of commeri' cal concern in the area of Pilgrim 3 Station. Table 4-1 indicates the reported commercial harvest of g Irish moss in the vicinity of the station. The harvest has t fluctuated from year to year (Table 4-1). This species is representative, in many respects, of benthic macroflora in the Pilgrim Station area as a dominant species. 4.2.2 Rockwe6d (Asconhvilum nodosum) (Figure 4-1b) t Ascochv11um nodosum is the mo.st abundant intertidal macrophyte at g Pilgrim Station. It is a long-lived, sessile brown

algae, and W

thus a good indicator species of a continuous long-term stress, 1 As an intertidal species, it should reflect any stress from a shoreline discharge such as that of Pilgrim Station. 4.2.3 Amphipod (Acanthohaustorius millsi) (Figure 4-;c) The haustorid arphipod, Acanthohaustorius millsi, is an abundant subtidal species collected in the vicinity of Pilgrim Station. It is a burrowing amphipod that prefers a fine sand substrate. As a subtidal

species, A.

millsi is somewhat intolerant of increased temperature. A. pillsi is thus representative of a l temperature-sensitive, subtidal species occupying a sandy l substrate, a 4.2.4 American Lobster (Romarus americanus) (Figure 4--1d) The American lobster is an important commercial species, is a detritivore, and is a repres2ntative of many benthic g invertebrates. The commercial catc? in the vicinity of Pilgrim g Station has remained stable over the past five years (Table 4-1). Iobsters inhabit rocky areas similar to those found in the immediate vicinity of Pilgrim Station. Lobsters may be considered an indicator species of environmental perturbations us they are long-lived. The mysid stage of lobster development is planktonic, occurring in spring. Thus, lobster may be regarded as representative of bivalves and other benthic fauna with entrainable planktonic larval stages. I i 4-3 I l l M E

) i lJ a sh h s/$q* 4 t e-l syv rg\\j e ikgge' 2 owx l IRISH MOSS, CARRAGEEN ROCKWEED Chondrus criscus Ascophyllum nodosum i I FIGURE 4-IA ANOIB R E P R ESENTAT IVE SPEClES

I f f \\ s ) t k'?, 4* k' h,; ! I ' 7..,. l < ikNQ-fl r,, I \\ \\ .9 3- ~ ,/ ^q k-2 Y ) I 5 / '

• % N

,.c _s b

/

Q l j ':.. }h :' p*?. Y Q ~K. r g ,w I e J..,, <.L y, gMflis;I,bN4: [Qg -l from f The Tamilies and Genera of Marine Carrtridean Amphipoda !JiPHIPOD (Representative of i Acanthchaustorius millsi) f E (( D g &~R \\ s. vS , _ ~.. T#/ i 97 i I cQ't k: > ; q O ^ l N u. 'd'- / } d I LOBSTER Homarus americanus i FicuRE 4-:C A N D 10 REPRE S ENTATI V E SPECI E S

j 1

4. 2. 5 - Blue Pussel (Mytilus ed,ulis)

(Figure 4-1e) The blue na2s sel is an abundant intertidal species collected at Pilgrim Station. It can be described as a habitat-forming organism although it inhubits most substrate types in the vicinity of Pilg:in Station. l The veliger stage of mussel development is planktonic and, thus, susceptible to entrainment. Both initiation 7f spawning and l settling of pediveliger larvae are controAled by ambient temperature condiz. ions (Sherman and Lewis, 1967). Generally, Mvtilus is a tolerant species as is evidenced by major industrial problems resulting from y;(tilus biofouling of water-use systems. 4.2.6 Cc=non Periwinkle (Littorina,littorea) (Figure 4-1f) Littorina littorea is an abundant intertidal gastropod collected l in the vicinity of Pilgrim Station. This species is an important component of the intertidal co= unity because of its high population densities in many parts of its geographic range. It is an economically important mollusk in western Europe where it 'I is harvested for food (Wells, 1965). The periwinkle is found on rocky substrates and macmphytes- (such as Ascochv11tm nodosum) both of which are found a: the station discharge. It is an omnivorous browser, feeding on detritus and epiphytes. h Tne egg capsule and veliger larvae stages of the periwinkle are 3 -planktonic

and, thus, subject to entrainment.

Adults are j relatively i=nobile

and, therefore, are subject to thermal influence from the onshore discharge at Pilgrim Station.

4.2.7 Atlantic Menhsden (3revoortia tyrannus)(Figure 4-1g) Menhaden is an open water migratory species which is affected by many generating stations. This species has been affected by both impingement and entrainment at intake structures and entrainment I in thermal plunes (Young, 1974). Menhaden are sensitive to extreme envi.conmental conditions and, thus, indicative or stress resulting from environmental perturbations. Menhaden are representative of most clupeids and other migratory species. Menhaden are planktivorous, feeding on phytoplankton (e arly life history stages), and zooplankton (late life history stages), and are prey for species such as striped bass and bluefish. Migratory habits of menhaden have been described (Sigelow & Schroeder, 1953). 1.ike other clupeids, menhaden are subject to fluctuating year class strength. Mentaden is a co=ercial species in Cape Cod Bay -(Table 4--1). eum

4iIl sjM9 v MU; SEL Mvtilus edulis 5 Il -{ 4't.. Bib k. Qp ) I i I PERIWINKLE f Littorina littorea L l l FIGURI 4-lE AND t F { REP R E S ENTATIV E SPECIES j 5'

Menhaden are warm water fish, rarely found in waters less than 500F: thus, their presence in the cooler waters of Cape Cod Bay is seasonal (Bigelow and Schroeder, 1963). tbrtality of menhaden attributable to thern.il discharge has been obse:Ted at Pilgri:n Station. 4.2.8 Winter Flounder [P seudocleurone cte s americanus) (Figure 4-1h) Winter flounder are commercially important in Cape Co$ Bay (Table 4-1) and are the dominant species collected in trawls in .1 the vicinity of Pilgrim Station. They are also of recr e stional Lmportance in the sport fishery of the area (Table 4-2). Winter flounder have been affected by many power stations located in es tu aries, both through entrainment of planktonic larval stages and impingement of adults (NUSCO 1973). At Pilgrin Station, winter flounder larvae constitute one of the most numerously entrained ichthyoplankton species; however, few adults have been impinged. The winter flounder at Plymouth Station is probably a localized population with spawning occurrifig in the Plymouth-Duxbury estuary (personal corr.tunication, R. Fairbanks). "his localization is also suggested by the studies of Howe and Coates (1975). Winter flounder are benthic fish usually round at depths between 1-40 meters. Since they prefer a soft, muddy or sandy substrate, they are regarded as a representative of sandy e trates of f shore of Pilgrira Station. s 4.2.9 Pollock (Pollachius viregj (Figure 4-11) Pollock were the most e.bundant fish species collected by gill netting in the vicinity of Pilgrim Station. Pollock were also an abundant sport fish as reported in the 1973 and 1974 creel census frCole u-2). Pollock observed in this area were primarily fish of year-class III and IV. p Pollock have a life history similar to cod; both are offshore spawners with planktonic eggs and larvae. Pollock ichthyoplankton are also regarded as representative of cod in 1 that both are subject to entrainment in late fall and early winter. Although pollock have been collected and observed in the immediate vicinity of the power station, both at the intake and thermal discharge, there have been no observed mortalities either through impingement or entrairment in the thermal pltrae. 4.2.10 Cunner (Tautocolabrus adscersus) (Figure 4-1j) The cunner is a resident species which inhabits rocky areas. Unlike winter flounder, they probably spawn in the vicinity of Pilgrim Station. Weir eggs are planktonic and, therefore, are 1 subject to entrai ment. Adults are subject to impingement. t u-5

~ O. N: A \\ g s " m:@k R q2 s I yd ' 4__ > _ /,g MENHADEN Brevoortia tyrannus g 1 l k i Ps ,e ,. f '\\ - gnddf if I a ,/, s. L n& n. s..

• , ^

f {fgh,.. m ^ I =n,. y myggg;Y . i

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y :-- l y m _? Q/,/ ~ _/ @.ft;g hyyW

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,f';. gyp 9 f), l hN + 1 WINTER FLOUNDER Pseudopleuronectes americanus l' fren Tisnes of the Gulf of P.aine F IG UR E 4-tG AND lH sivelew r.reece: R EP R ES E NTATIVE S P EC IE S I

. t&tM k Qg,5q:ji np 'T'a'(f [LQ.f,(0'!$@jiC" f ...1 L $$L>.b&k y;..J.$$ g N v4-aid .2 .f"f) 8 h y -4h%@@ $g,i&&W t v I l IJERICAF POLLOC); Pellachius virens I h dY&c 4h c M .'4M,g 4-I i i L-CUNNER Tautocolabrus adspersus i 5 l- ( l 1 from F i G U R E 4 * ! !

t. N D 1)

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RE PRES ENTATIV E SPECl E S 1953 J

Cunner is of some recreational value as a food fish but is usually not regarded as a sport fish. Cunner were the most numerously entrained eggs and. Larvae and are h an abundant species in the 1_ mediate vicinity of Pilgrin Station.

Cunner, Irish

moss, and lobster are representative of biotic co= unities inhabiting rocky substrates such as that found near the station.

4.2.11 Rainbow Srelt (Osrerus w rdax) (Figure 4-1k) The smelt is an anadromous species rarely found more t,han one mile frca the coast'. 7 pawning takes place in spring 3 (April-June) in the upper freshwater reaches of estuaries and g rivers. Adults reuurn immediately to saltwater, inhabiting estuaries or marine vnter just beyond during the su=cr. Smelt are one of the species.mpinged at Pilgrim Station. 4.2.12 Atlantic Silverside (Menidia penidia) (Figure 4-11) The Atlantic silverside is an ir:portant forage fish at the { Pilgrim site. It inhabits shallow

water, generally in large schools.

Adults could potentially be af f ected by the therral 3 plume and impingemant on the traveling screens. The larvae of 5 3 the silverside could also be entrained at the intake structure. / The eggs are adhesive attaching to vegetation in the spawning 3 area

and, therefore, entrainment is probably not a concern as 3

indicated by the absence of silverside eggs in the entrainment J ctudies. mi la 4.2.13 Alewife (Alosa oseudoharenets) (Figure 4-1m) Alewives are one of the forage fish species in the area of the Pilgrim site. They are anadremou s, spawning in some of the 'l rivers and streans in the area. In salt water, alewives feed on 4 plankton such as diatoms, other algae and small crustaceans. Alewives serve as food for prec'aceous fish, birds, and to same extent, man. Pilgrim Station operational data suggest alewife eggs are not entrained and the larvae are infrecuently entrained. Some small alewives ne probably impinged on the traveling screens a.a are a group)d into the unidentified clupeid category in the g screen-washing program. ? A I I I s 4-6 5

ll /!k Y A; ,v.v.e ~I 1 %Y?b :? bl, SMELT osmorus mordax v lb.h. i h <.; m m.a,a .,,n -

1. 6 ctr'.'

hM',i'.t,.>>iU.T:'.','.,'.*;.':.'~ k 4* k- ...,y. c.,..,,, a, %.9 c.h Q.e.4. gyty,m,.0,.., i '. N, Y,,th t,p <.;qc g* gn1*N. ;, , n

7 g, e.

tpi a rM.N.,v L. V.?ts Rdy&OV-D ,$e;; " SII.,VERSIDE Menidia menidia i

'Th on' i

Thg ih'#rh*,h,f,Y,'ih,*h'gT[ g p F T_, /' ,w. y $ Y. 'LEh'IFE Alosa_ Escudoharenaus F I G U R E 4.ig, it a g g frem E S E NT ATIVE S P ECI ES ni. e ev S re e 1953 ' ' - ~ - ~ " - - ~ - - - - _ _ _

I l TA111E. It-3 C111.CK1,1sT stertrJtY or RF_PRI_51.r4Tm Ivt Srt.CItJ; Ario sm?Ior&ur I i l Irista Winter Pbas Ascophyllum A,s.h i g w.) ynt.st er Periwinkle Mussel M< r.fuelen rieww>1er hell. ek Osnrer wit SilverpJile Ale,v;1r tainaj nant 51=*cies X X X X X X X lascal resielents X X JL 1 X X 1 1 X X 1 X 1 1 X Fteyratory Ccure.ercial X X X X X J ms = =r t.arce 5:= *t t Stwcies X X X X X Omnerunity Tygc 1 1 t.st tsarine f% tina lunck Sc'utrate X X X X 1 1 X silt Sulistrate 1 1 1 X 1 1 X X gen W.ater X Itabitat Rissner X X Inter t ial.a 1 Subt letal X X X X l Tr3 hic level Producer X X INtrivote X X 1 1 1 i f i 1 1 Paimery Consimmer 1 X 1 1 1 Sacoalary Consumer 1 Tertidry Constaurer .e rce of Isspact EntJ ai renent P P P A A P P P P P A Jugeig erarmt A T'eetmaJ Pltrae P P X-tall 2n (Juis cate<psty. 1 - scene lite staoe f alls in this catefiry.

• - gwater*tia l smarce of impact.

A - identitimi as a smarce ut irrsuct on tJais 31 cies at tleis stat nem. 1 et 1

4.3 EEFr,rcTCES - SECTIOli 4

nigelow,

!!.b., and Schroeder, W.C., 1953. Fishes of the Gulf of ma ine, U.S. Fish and Wildlif e Service Eulletin 53, 577 pp. l Loston Edison

Company, 1974a.

Envircnmental Report: Pilgr3Ja !1uclear Power Station - Unit 2.

Poney, A.D.,

1966. "A Biology of Marine A3gae," Hutchinson g Educational, London, 216 pp.

Green, J.,

1971. "The Biolrigy of Estuari.no Animals," University of Washington, Seattle, 401 pp. EI !! owe, A.D., and Coates, P.G., 1975. Winter riounder Movements, Growth and Mortality Of f Massachusetts. Trans. Amer. Fish Soc. i 104(1): 13-29. Kizulo, O., Ed., 1970. Marine

Ecology, a t.

Comprehensive, Integrated Treatica on Lif e in Oceans and Ccostal Waters," Wiley-I Interscience, London, 681 pp. 14crthea st Utilities Service

Company, Semiannual

Report, Ecological and liydrographic Studies, April, 1973-September, 1973.

Pr akash, A., 1967. " Growth and Toxicity of a hariae i Dinoflagellate, Gonyaulag tamarennin," Journal Fish Res. Bd. Can. 24 (7)21590-1606. h

Shermen, D.,

and Inwis, R.D., 1967. Seasonal Occurrence of Larval g Lobsters in Coastal Water of Central Maine. Proc. 1:at ' l Shell Assoc. 57: 27-30. United States Atomic Energy Commission, Final Environmental Statement Related to the Proposed Pilgrim liucieur Power Station - Unit 2, Docket lio. 50--4 71, 1974. =

Wells, H.W.,

1965. Maryland Records of the Gastropod, Littorina _li ttore a, with a Discussion of ractors Controlling its Southern Distribution, Chesapeake Science Vol. 6 !;o. 1, pp. 3 8--4 2. A Growing

Young, J.,

1974. " Menhaden and Power Plants Concern," Marine Fisheries Review 36(10):19-23. I I I E

SECT 2,0!i 5 LIFE HISTORIES AND TE!'PEPMJRE TOLEPA!:CE PILATIVE TO P2PPISE!CATIVE SPECIES 5.1 IRISH MOSS {cHOtogDS CRISPU_S) g 4 Irish Moss is a benthic marine red alga which inhabits rochy substrates from below low water (including inuertidal p>.>1s) to a g g depth of 38 meters. Usually, however, its maxitium density occurs 5 from low water to 6 meters below low water. Chondrus is found i ~~ frce New Jersey to Labrador with greatest abiiEdance towards the g center of this range. g 1 Chondms reproduces throughout the year with peak rep.;oduction occurring during late spring and sum:Ter (Prdaco, 1971). Chondrus reproduces both sexually a.nd asexually. Carpospores are produced f in early spring and tetraspores in late sum:ter and early fall. Spores are non-buoyant and thus settling occurs from August i through November. The Irish Moss thallus is produced from a

erennial holdf ast and is usually attached to a rock or ledge outcropping.

Shells and small stones are also suitable substrates. A number of morphologically different forms of 1, Chondrus have been identified. Morphological' differences are generally attributed to certain environmental factors, such as light, wave action, depth, salinity, or predation (Prince, 1971). l Chond ts criscus is commercially harvested for carrageenan a gelatinous extract used as a suspending agent in the

brewing, a

baking, pharmaceutical, and dairy industries. g s An Irish Moss harvest area lies between Rocky Point and Manomet Po i.nt, Plymouth. Generally, the density of Irish Moss appeared l highest in August, from 1972 to 1974, and lowest in February and Pay (1972-1974). Maximum density also appeared greatest in Areas i shallower than 20 feet below mean low water (MLW), especially at Rocky Point. Upper thermal tolerance limits of chondrus tetraspores and g carpospores has been determined. Carpospores have survived 950F 5 temperature at six minutes exposure when acclimated to 200F. Tetraspores were found to be less tolerant of heat than carpospores. Maximum tolerance was 800F. At this temperar.ure, however, both carpospores and tetraspores were kiued in 4 to 10 days. Maximum growth occurred at 700F for all developmental stages (Prince, 1971). 5.2 ROCTWEED (ASCOPHYLLUM NODOSUM) I' l Ascochv11um nodosm is an intertidal brown algae usually found in l rocky areas protected from intensive wave action (Smith, 1951). It is a widely distributed, north Atlantic species which is found I from labrador to New Jersey. ,Ancochv11um is a long-lived species 5-1 l = l 5 1

I with an average life span of 12-13 years. Most other macrophyfe I species have much shorter life spans; for

example, Pucus vesiculosus, another brown alga commonly found with Asconhvilum (including at Pilgrim Station) has an average life span of one year (Boney, 1966).

Garetophyte produ: tion in Ascochvlhn occurs from f all to early cpring with rest vegetative growth occurring hmnediately from I early spring through late sur=cr. Ascophyllum in the most abundant macrophyte species at Rocky I Point, in Manomet Point, while Pucus is abundant at White Horse Desch. The density (grams dry weight per square meter) appears to be stable from year to year with seasonal variations resulting from decreases in spring (Figure 6-5). Available infor=ation on temperature tolerance of A. nedosum N indicates that it can withstand water temperatures as high as 93 5 to 970F (Fritsch, 194 5). More infomation is available on other northern species similar to As cochylhim. Fucus vesiculosi_s suffered only a slight reduction in photosynthetic activity when I exposed to 9007 water after accidnation at 750F (Boney, 1969). t 5.3 AMPHIPOD (APAmORAUSTORIUS MILLSI) I This haustorid amphipod is a subtidal benthic marine species. It is the ncst con:nonly occurring species of the f amily Hanstoridae in Cape Cod Bay (Sameoto, 1969a). It is a sand-burrowing amphipod that feeds by filtering fine fcc d particles from the interstitial water of sands. A previous study in Cape Cod Bay reported A. ;nillsi, to have a life span of between 12 and 17 months (Sameoto, 1969a). The same 6 h study indicated that females produced only one brood of young and 3 then died. Ovigery appears to be somewhat dependent on water temperature, as 13 percent of females collected were ca..rying eggs at 450F, while 54 percent of the females were carrying eggs I at 490F. The number of eggs increased with increasing body weight of females up to 19 eggs per female (the mean is 8 eggs per f emale) (S ameoto, 1969a). I The density of A. millsi was reported to increase with increasing water depth (Sameoto, 1969a). In the vicinity of Pilgrim Station I they are collected in sand substrates at White Horse Seach, and of fshore of the discharge location. Density of A. millei at 'lgrim Station appears to be greatest at 20 feet belcw mean low ater (MLW) rather than at 30 feet below (MLW). Thermal tolerances for A. millsi have not been well defined for individual lif e stages. 6ne hundred percent mortality occurs at I approximately

970F, although no mortality was observed during a brief exposure (3 minutes) to water at 350F.

Mortality of intertidal a phipods occurred at higher temperatures (1060F) I i 1 5-2 gm

indicating that intertidal amphipods are less sensitive to th ermal increases than subtidal

species, such as A. rdlisi (S ameoto, 1969b).

l 5.4 Av.IRICAN LOSSTER (HOMARUS A'GRICANUS) The lobster is a benthic marine crustacean inhabiting coastal waters from the continental slope to the low wat ermark and ranging f rom North Carolina to Labrador. Highest numbers of this species occur near the center of this range, off the Maine Coast to Newfoundland, where ambient bottom temperatures normally vary from 2BoF to 750F (McLeese and Wilder, 1964). I obster naturatian rates vary with water temperature. South of the Gulf of St. Lawrence, sexual maturity occurs when the lobster reaches approximately 1/2 pound in weight and/or 7 inches in length. In contrast, lobsters in the northern part of the Gulf reach maturity at nearly 2 pounds and 12 inches in length. Since a 1-pound lobster is the usual minimum co=ercial

size, many g

lobsters inhabiting cold water cre removed before ever g reproducing. (McLeese and Wilder, 1964). In Cape Cod

Bay, lobsters regain 5-7 years to attain legal commercial size, and are approximately 1 pound in weight.

A mature female lays between 5,200 and 50,000 eggs, depending l upon the age and size of the individual, from June to September;

however, fecundity

=ay decrease in more northern waters (Squire s, 1970) (7,000 to 23,000 eggs for nortbarn f emales). Females retain their eggs for nearly a year, this too being dependent upon terperature; wcrmer water hastens egg development. Hatching takes place from mid-June through Septembcr for most i, lobster populations (Perkins, 1972). The first few larval stages f of lobster are planktonic. Sherman and Lewis (1?67) have reported that the normal hatching process of lobsters occurs from June to August as water temperatures range from 54-590F. In the investigations of the lobster fishery of Long Island Sound l by Lund and Stewart (1970), the computed survival rates of 4 lobster from larval State I through IV was 0.52. This is extraordinarily high and suggests low predation (which is unusual) but ray be the result of low density. Lund and Steward (1970) indicated that during a etenophore bloom there was a drastic reduction of all planktonic forms - including stage III of the lobster. This occurred in late July of

1966, 1967, and

1969, and August of 1968 and represents the only indicated major reduction of larval forms during the sompling period in Long g

Island Sound. 3 Few lobster larvae have been collected in the vicinity of the g Pilgrim Station, although there is a sizable adult population. g 5-3 5

9 J l An on-goi.ng program at the Pilgrim Station monitors the lobster 7 catch per pot from Rocky Point to Manomet Point, Plynouth (Figure 6-8). The average catch per pot in the sample period from April [ through October was approximately 3.7 individuals per pot. Peak 5 abundance during the years 1972 through 1974 was in late August to early October as reported by catch / pot data. The greatest abundance of lobaters occurred at Rocky Point and Manomet Point where the best habitats exist. Few definitive studies have been written concerning the lethal thermal tolerance of homarids.

However, the use of thermal effluents have toen suggested for use in the rariculture of i

lobster and other marine invertebrates. M3 intained at an optir.um growth temperature of between 71 to 750F in the laboratory, hatching I lobsters have attained comercial size in 2 years after (Hughes, et. al, 1972). E McLeese (1956) recorded the 48-hour thermal tolerance of lobsters g acclimated at 250C (77 0F) to be 30.50C (8 6.9 0F). at 30 percent salinity. '1he 24--hour TC50 of lobster larvae was determined to be 84.50F (Battelle Memorici Institute, 1974). 5.5 ELUE MUSSEL FtTILUs EtuLIs) The ccmmon mussel is found i.n all northern hemisphere temperate I marine waters. Eutchins (1947) found the southern liedt of distribution corresponded closely with 800F isotherm monthly Mvtilus, edulis is distributed intertidally I. maximu:n temperature.to 30 feet below mean low water, but reaches its greatest density at the mean tide mark to just below mean low water. Mytilus inhabits tidal flats and is attached to hard substrates including I rocks and shells surrounded but not covered by silt and mud. also estuarine and occur where normal salinities do Mussels are parts per thousand. Mvtilus is able to I not fall below ten withstand short periods of low salinity, as low as four parts per thousand (Hutchin s, 1947). Spawning occurs in late spring when water temperatures reach approxi:nately 570F and above. Eggs and spern are liberated at high

tides, sometimes in such large volumes that the water becomes opaque.

Lubet (1956) found that highest numbers of gametes released corresponded to the new and full moon during the spawning season. Zygotes develop into ciliated veliger larvae which are planktonic for several weeks. Cilia provide the larvae with a small degree of motility. Development of a foot begins during this period, and the larva (pediveliger) begins a benthic existence. The pediveliger is still motile and therefore able to locate a suitable habitat. It attaches itself to a hard substrate with byssus thread. However, if its location becomes unsuitable it can reabsorb the byssal threads and move, to some degree, with remaining cilia. 5-4

l Post !Lvtilus pediveliger larvae settle to the bottom from mid-June through mid-July in Connecticut (Engle and Losanoff, 1942). Tc=peratures during settling were between 54.50F and 66.20F. An R es: tended season of settlement was reenrded by Ra.1ph and Henley 5 (1952), where temperatures in the experinantal area never i exceeded 66.20F. Settling substrate usually contain algal a filaments and a solid object to which the byssus thread are g attached. Mvtilus edulis were most abundant at White Horse Beach transects during Februarf and

May, and lowest in August and Novemba r.

Intertidal areas had the greatest overall density. Kennedy and lii.hur sky (1971) reported the upper lethal toleranca temperature of a species of Mvtilus to range from 80-1050F. E Henderson (1929) recorded the upper to17rance temperature icvel 5 of Pytilus at 105.40F when acclimated at 590F. The 24-hour median tolerance was conservatively estimated at 34.20F, g Gonz ale: (1972), through field observations and laboratory 3

studies, reported extensive Mvtilus rortality heediately adjacent to a power plant discharge.

Feeding was noticed to a ceased at 770F. Ererko and Calabrese (1969) found minic.al g survival of Mvtilus larvae when held at 860F for 16--17 days. At 770F, more than 50 percent survived at moderate ocean salinities. ~ t 5.6 COP. MON PERIWDELE (LI""ORINA _L_I_,'I'rOPIA) The cccmon periwinkle is a typics1 intertidal inhabitant of rocky shores in the Nort.h Atlantic Ocean. Its range extends from ,j Greenland, down the Labrador coast to New 'ersey. The extension of its range from the Maritime Provinces southward has occurred 3 within the last hu. dred years. Its southern range limit appears E to be correlated with summer water temperatures near 70DF (Wells, 1965). In this species, planktonic egg capsules with developing embryos can be transported considerable distances before hatching. Usually 2 to 4 eggs are contained in each capsule. Free-swimming l veliger larvae emerge from the capsules after a development period of about 6 days. These veligers remain planktonic an l additional 2 to 4 weeks (Green, 1971; Wells, 1965). While the avera ge life span fer L. littorea is approximately 2 years for some populations, other populations may live much g longer (Gre en, 1971). There are apparent differences in breeding 5 cycles of open--coas t and e stua rine populations, open-coast populations spawning in March and estuarine populations in g January. Individuals are sexually mature at a shell height of 3 about 11-12 mm and repr c>duco for the first time dur$ng their second or third winter on the open coast (Fish, 1972). This a generally occurs 17 to 18 months after larval settlement 5 (Williams, 1964). l "he release of egg capsules occurs cradually cver a period of 10 to 12 weeks, and the pelagic phase requires 6 or 7 weeks 5-5 am 5

(Hilliar.s, 1964). At Pilgrim Station, eggs were collected from April through August and larvae f rom July through August. L. littorea is an abundant intertidal gastropod collected frem Station. The density in rocky I rocky substrates near Pilgrim areas ranged frcn approximately 30 to 1,000 individuals per square meter. The periwinkle is found both on rocky substra te s macrophytes. Although it is o nivorous, it is generally I and considered a browser. L. littorea usually feeds when suhnerged by the tidet however, they may feed when not submerged. l Fraenkel (1960) reported the upper lethal tolerance te=perature of L. littoraa_ to be approximately 104 0F. 1:ewell et al. (1971) reported

t. hat the upper lethal temperature was dependent on exposure time and acclination temperature.

They found that b littorea acclirated to 41 and 510F water, survis ed for a shorter time when egosed to water temperatures greater than 860F than j organisms acclimated at 61 and 700F. McDaniel (1965-) reported N that the themal tolerance of L. littorea was also affected by treratode parasitism. Organisms parasitized by C,mtocotvle g linoua were less tolerant of temperatures above 1020F thar: non-g parasiti: tad organisms. 5 5.7 ATLANTIC MElmADE!: (??r/ccRTIA TY?mmUS) The Atlantic menhaden is a coastal marine pelagic species and is j an important East Coast commercial fish species. It is neither a game nor a food fish, but is primarily used to produce fish meal and oil used in a variety of industrial processes. j I The range of menhaden extends from trova Scotia to Florida, the northern limit being dependent on seasonal changes in water temperature. Previous studies indicated that they are not found in water less than 500F (Bigelow and Schroeder, 1953). Schools I of adult ...ahaden migrate north along the coast to Cape Cod Bay as water temperature increases from late April through November. Menhaden are planktivorous, feeding on diatoms, copepocs and other planktonic species. Schcoling menhaden are responsi.ble for I sporadic depletions of plankton as the fish move along the coast. Individuals of the same age class usually school

together, and older fish travel farther north with each migration.

Menhaden are preyed upon by fish species including

bluefish, haddock,

'I

pollock, cod, and swordfish, Bluefish are responsible for large kills of menhaden when they drive schools into estuaries and onto beaches.

Natural kills of this type have ranged up to 1.f-2 millien menhaden (Anonymous, 1974). According to Henry (1971), menhaden grow rapidly until their fourth year, and growth rate therea:ter de clin es. Utilizing I returns from more than 1 million tagged fish, Dryfcos et a1 (1973), computed the average annual survival rate of menhaden in 1966 to 1968 as 0.22, with a range of 0.13 to 0.37. The average 't I 5-6 E

exploitation rates for the years 1966, 1967, and 1968 for 1:ew York were 33.6, 47.1 and 55.7, respectively, and the mean instantaneous natural mortality was 0.52. g Little is known of the breeding habits of menhaden. Although some menhaden attain maturity at one year of age, most menhaden 3 a.r o sexually mature in the third year. The nu.r.ber of ova E reported per iemale varies widely in the literature, but the number of eggs increased according to the length of fish. Estimates of 38,000 to 631,000 eggs per female were reported by 111gham and 1 icholsor. (1964). Eggs are buoyant and, thus, planktor.ic. Menhadeneggs,thoughl rarely collected at Pilgrim Station, were found in June and July, in ichthyoplankton collections in

1974, Menhaden larvac were first observed in Cape Cod Bay on June 6 and last collected on tioverlor 5.

Water te:rpcratures during these dates were greater than or equal to 500F. This is in close agreement with Bigelow j and Schroeder's (1953) account of themal requirements of p menhaden. The Bureau of Cecmnercial Fisheries in Beaufort, 1; orth Carolina, l has determined thermal tolerances for menhaden. Yearlings salinity of 7 ppt survived acclimated to 71.60F and a B9.60F-90.20e at 4.-6 ppt salinity. The same results are reportedh for adults and larvae. Lewis and Hettler (1968) determined the upper thermal tolerance of 90.20F-93.20F, but found upper thermal tolerance is dependent on acclination temperature. For example, menhaden have an upper themal tolerance of 93.2 to 95.00F when acclimated at 80.60F (Hoss et al., 1973). A temperature of 650F was found to be lethal when menhaden were acclimated at 590F. Battelle Memorial Institute (1972) deterni.ned the 24-hour Tin of 3t adult menhaden collected in th,e vicinity of Pilgrim Station to be 860F. [ 5.8 WIl m Flout: DER (PSEUDoPLrunotac7Es AMrRIcAnus,) flounderisaright-sided, marine,flatfishspeciesl The winter l commonly found along the Atlantic coast from Labrador to Georgia. benthic fish that inhabit coastal are Winter flounder are and prefer a

soft, muddy substrate depths of 1 to 40 meters covered by Zostera m_arina or similar vegetation.

Winter flounder average between 12 to 15 inches inlength;g however some adults attain 2 feet in length. Growth experiments 4 conducted with winter flounder from Charlestown Pond, Rhode Island (Berry, Saila and Horton 1965) indicate a maximum growthg ine; ease in length of 293 millimeters between age classes I and5 V. Growth decreased thereafter to a maximum of 320 mm at age IX for males and 393 : n f or females. Maximum length was attained atg year XII. g 5-7 E

Q

Berry, Saila and Horton (1965) computed the annual total 7 mortality rates as 0.56

'and 0.65 for males and

females, re spe ctively,

from Charlestown Pond, Rhode Island, and 0.51 to 0.58 for males and f emales, respectively, from Marraganse*.t Bay.

However, these high survival rates result from a failure to consider the number of eggs and larvae which are flushed out to sea from large estuarine s pawning and nursery areas.

Pearcy (1962) calculated survival rates from slopes of biweekly averages lfor both year classes 0 and I. Monthly survival rates are 69 percent for age class 0 and 92 percent for age group 1. Pearcy also found decreasing mortality with increasing age. l Saila, as reported in Pearcy (1962), estimated the fecundity of 1 winter flounder at 630,000 eggs. Poole (1969) calculated from tagging returns the servival

rate, fishing mortality, annual

[ mortality, and annual natural mortality for winter fl. ender for ) 5 years. j Spawning occurs at night between January and May in New FJ. gland l waters. Eggs are demersal and adhesive, usually clur. ping on the bottom. Incubatien requires 15 to 18 days at water temperature of 37 to 380F. Eigelow and Schroed er (1953) estimate average fecundity at 0.5 to 1.5 million eggs per female. More extensive studies by Topp (1968) estimate fecundity of flounder caught at i E111sville, Sandwich

Creek, and White Cliffs, Massachusetts at j

435 thousand eggs for a year-class III fish and 3.329 million eggs for a year--class V fish. So gravid year-class II fish were i found by Topp. Winter flounde:

eggs, because they are demersal, were rarely collected at Pilgrim Station, occurring in April and May sa: ples.

However, larvae were abundant, occurring from March through July. I Peaks of abundance occurred on April 24, May 8, and June 28. samples for winter ficunder adults at transects off P.ocky l Trawl Point, Plymouth, indicated presence of the species throughout the year. Highest abundances occurred from early July through October, in 1972, with a similar pattern in 1973 (Figure 6-16). IMeannumbersofindividualspertrawlduringtheseperiodsranged from 67 to 100 in 1972 and 40 to 176 in 1973. I An upper thermal tolerance limit of 59.90F when acclimated

• .t 76.60F was recorded by Hof f and Westman (1966).

Gift and Westman (1971) estimated ' Ln ' s (lethr. temperature for 50 percent I nortality) at 88.93 to 89.790F for fish acclimated between 68.9 and 76.60F. Huntsman and Sparks (1974) recorded the upper thermal tolerance for larvae at 83.6 to 860F. I.o w e r thermal tolerance limits were found to be 33.8, 34.6 and 41. CoF when Iacclimi.tedat44.6, 69.8 and 82.40F, rescectively.

However, Eigelow and Schroeder (1953) reported P. 1.sericanus in water at 280F.

l

l 5.9 POLLOCK (POLLACHIUS VIRrtis) l The American pollock is a marine species found along the Continental Shelf frcm the Gulf of St. Lawrence to !?ew

Jersey, t

Pollock are com: Ton in the area of Plymouth and Cape Cod Bay. They travel in large schm ls, feeding on

smelt, young

herring, and other small fish and crustaceans, especially shrimp.

Young pollock feed on copepods. They feed actively from the surface to depths of 200 meters. Pollock are cool water fish, rarely found at temperatures greater than 600F; large schools are uncommon if g temperatures exceed 520F. Water temperatures of at least 380F W are needed for adequate incubation of

eggs, although adults inhabit waters to 320F.

Spawning begins i'. December as soon as g water tettperatures reach 4 7--4 9 0 F. Spawning increases as 3 te.:rperatures f all to 44 0F and then decreases as temperatures f all to 360F. Fecundity is estimated at 225,000 eggs per female, but it can be high as 4 million eggs (Bigelow and Schrceeder, 1953). Eggs are buoyent and nonadhesive. Incubation requires nine days at temperatures of 430F and six days at 490F. Larvae remain near the surface for three months after hatching. Growth is approximately 1-2 inches per season daring the first year. Year Class I fish attain an average length of 5-6 inches and grow to 12-13 inches by Year II and 17-18 inches by Year-class III. Thereafter, growth

. ate decreases to 1 or 2 inches / year.

The average maximum length is 30 inches (at 9.5 years). Pollack cun, 3 however, attain 19 years of age. T At Pilgrim Station, poilock were the most commonly occurring species in cjill nets at Rocky Point. Peak abundance vas observed t in

April, May, and June and also in llovember and December, I

corresponding with spaw11ng season. Large schm ls of pollock were a.lso observed near the site by divers. E i The pollock's upper thermal tolerance has been determined to be, 82.40F (de Sylva, 1969). 5.10 CUP.cR CAUICGOLAERUS ADSPERSUS_) The cunner is a marine species found along the western 1; orth Atlantic coast from Labrador to the Chesapeake Bay. Cunner prefer rocky areas covered with algae as well as pilings and shipwrecks which serve as refuge areas. These areas are also habitats for small fish and crustaceans, the main prey of cunner. Cunner are found primarily between 3 and 10 meters but have been caught as deep as 150 meters on Georges Bank. They do not school but do tend to congregate near suitable habitats. Cunner are year-round residents in their range moving into deeper water only during heavy freezes (Green and Farwell, 1971). Spawning occurs from late spring to summer at water temperatures usually between 55 and T!OF. Eggs are buoyant, tran sparent, and 5-9 5

I are nonadhesive. Incubation requires 40 hours at 70-720F and Year-class I fish are usually 2.5 to I three days at 55-650F. 3 inches aM 3 to 4 inches at Year-class II (Bigelow and Schroed er, 1953). Sexual maturity generally occurs during Year--class II, females usually being slightly longer than males. Cunner were abun*. ant in gill net collections at Pilgrim Station. Cunner larvae were sampled from July 2 to August 13,

1974, I

peaking it. abundance on July 30, 1974 Canner eggs cannot be separated fecn other labrids and thus are all grouped' together. In 1974 ichthyoplankton collections, Labrid eggs were first observed in early May, were extremely abundant in June and

July, and were rare during the remainder of the su=or months in Cape Cod Bay.

F,inne (1970) determined the thermal tolerance limits for adult I cunner to be 84.2 to B60F when acclimated at 64.4 to 71.60F, and 33.8 to 37.40F. These were the I 77.0 to 78.80F when acclimated at upper lethal tempe.ratures. Lower lethal li:r.its were recorded as 1 410F and 326F when acclimated at 64.4 to 71.60F and 33.8 to 37.4 *F respectively. 5.11 RAINEOW SMILT (OS!ERUS MORDAX) The rainbow smelt is anadromous and rarely found more than one mile from shore or deepe-than three fathoms. In addition to marine populations found from Labrador to Virginia, there are landlocked popu~ ations existing in lakes of New

England, the I

Maritime Provinces, and the Great lakes. smelt gather in harbors and in brackish estuaries in the I Adult fall. During the following

March, when water temperatures j

increase to 40-420F, spawning begins in fresh water areas of rivers and estuaries. Peak egg production occurs at water temperatures of 50-570F, and spawning is completed by May. Fecundity has been estimated by Bigelow and Schroeder (1953) at g 40,000 to 50,000 eggs per two ounce female. Sexual matarity occurs during the second winter (McMen zie, 1964). Smelt are cold water fish, and van Oosten (1953) reprted that smelt pref er water eccler than 590F in Lake Michigan. de Sylva (1969) found that smelt acclimated fren 50-590F had an upper thermal tolerance of 71-840F respectively. Adult smelt were collected in the vicinity of Pilgrim Station in April and Never.ber in 1974, while larvae were present primarily in spring. 5.12 ATR.NTIC SILVERSIDE (MINIDIA MINICIA) The silverside is divided-into two subspecies on which occurs along the eastern coast of the United

States, (the northern subspecies, M. nenidia rotota, and the southern subspecies is M.

5-10 I

menidia menidia). The upecies is found all along the eastern coast. They are found in shallow water, especially during the spawning season. The diet of silversides consists of copepods, mysids, shrinp, anphipods, cladocera, etc. Silversides are usually found near sandy or gravelly shores. l Spawning occurs from late spring into early sucter. In the area ot Pilgrin Station, silversides pr sbly spawn once during their E life (Bayliff, 1950). Spawning .; curs in shallow water where 5 eggs and milt are deposited in strands which cling to vegetation. Bayliff (1950) observed about "300 mature eggs and many smaller, E somningly dead or arrested eggs" in a ripe female. B i The silverside probably completes its life cycle in slightly more a than one year. Adult si.1versides reach a length of about g 120 millimeters and weight approximately 9 grams (Aus tin et al., 1973). The longest silverside collected in the study by Sayliff l (1950) was 140 millimeters. The temperature tolerance for adult smelt has been investigated by Hof f and Westman (1966), and Gift and Westman (1971). The E relhtionship between tolerance temperature and acclimation W temperature derived from their studies is: y = 40.34 + 0.70x 1 where = y is the upper tolerance temperature in degrees Fahrenheit, and x is the acclimation temperature in degrees Fahrenheit. 1' The residual st andard deviation is 4.98 and the correlation between these variables is 0.87. l Silversides are an important forage fish in the area. They have g been observed in the stomachs of

bluefish, striped

bass, grey bass, scup, Atlantic mackerel, Atlantic bonito, squeteague, sea cunner, silver hake, Atlant:.c cckf,

tomcod and squirrel

hake, (Baylif f 1950).

5.13 ALEWIFE Ul,OSA PSEUDORARENCUS) Alewives are one of the forage fish species near the Pilgrim site. They are anadromous, spawning in rivers and streams in the area. In Massachusetts, spawning generally occurs between the middle of April to the beginning of June (Belding, 1921). Eggs adhere to the stream tottoms. The incubation of fertili::ed eggs requires 48 to 96 hours at 720F. Young-of-the--year alewives reach a sir.e of 2 to 4 inches by the fall when they move from the breeding grounds to the open ocean (Belding, 1921). I 5-11 5

H [ Adults return to the rivers and streams to spawn in their fourth and fif th years in Connecticut (Mar cy, 1969). Approxir.ately 75 percent of the females and 68 percent of the males first spawned at age 4. The maximum age for the alewives was estimated at 8 years. Limited studies indicate that alewives return to the stream in which they were born to spawn (Belding, 1921), a The fecundity of alewives has been estimated at 48,000 to 360,000 eggs per f(male with an cverege of 229,000 eggs per female. The sex ratio during spawning was approximately 1 to 1 when averaged over the entire period t however, the beginning of tha spawning run is characteri:cd by the dominance of males (Kissel, 1974). !brtality through the life cycle has been studied for alewife populations. Kissil (1974) calculated that one young alewife mi. grated seaward for every 80,000 egge spawned in fresh water. g Fosa11 (1970) observed the percent of eggs which hatched was g related to t er:perature. Paximum hatching success occurred at l about 600F, and ieclined at higher and lower temperatures. Alewives are planktivorous. They feed on diatoms snd other I

tilgae, as well as the microcrustaceans of the

coplankton (B elding,

1921; 31gelow & Schroeder, 1953). Alewives serve as forage fish both in the ocean and during their migra tion and spawning activities in fresh water. The weakened conditions of adults at.ter spawning probably makes them noce susceptible to [ predation and disease. l i b k i 5-12 _________________n

/ 5.14 REFEnINCE.S - SECTION 5 }toferegnee for 5._1

Prince, J.S.,

1971. An Ecological Study of the Marine Red Algae g Chandrun pg.ipnus in the Waters of f Plymouth, Mass. PhD

Thesis, Cornell University, New York.

Foferences for 5_._4

Hughes, J.T.,

sullivan, C.J. and Shleser, R. 1972. Enhancutent 3 of Lobster Growth. Science. 177: 1110-1111 5

Lund, W.A.,

Jr. and

Stewart, L.L.

1970. Abundance and Distribution of Larval Iobsters, Emanin americanus of f the Coast of Southern New England. Proc. 1:st. Shell Ass. 60:40-49.

McLeese, D.W.

1956. The Ef fects of Tc=perature, Salinity, and l Oxygen on the Survival of the Icerican Iobster. Jour. Fish. Res. Ed. Can. 13:247-272.

McLeone, D.W.

and Wilder, 1964 Iobster Storage and Snip:nent. r Bull. Fis h. Re s. Ed. Can, No. 147; 69 pp. Perkins, If.C. 1972. Developnent Rates at Various Tc:nperatures of } E::bryos of the Northern Lobster 01amarus_ nmericanus, Kilne and Edwards) Fish. Bull. 70 (1) : 95-99. l

Sherman, D.,

and Lewis, R.D. 1967. Seasonal occurrence of Larval Lobsters in Coastal Waters of Central Maine. Proc. Unt.l. Shell. 3 Assoc. 57:27-30. E

Squires, B.J.

1970. Lobster (1,Loe.arun americanus) Fishery ead Ecology in Port Au Port Bay, Newfoundland, 1960--65. Proc. tkt. Shell. Ass. 69:22-39. ] References for 5-5 i Erenko and Calabrese, 1969. The cir:bined Ef fects of Salinity and Temperature on Larvae of the Mussel Mvtilus edulin. Parine Biology, 4:224-226. Engle, J.B., and Lasanoff, U.L. 1944. On Season of Attach =e.nt of 3 Iarvae of Mvtilus, edulis (Linne) Teology 25(4):433-440. 5 Gonzale=, J. 1972. Sea sonal Variations in the Responses of Esturine Populaticas to Heated Water in the Vicinity of a Steam-Generating Plant. PhD

Thesis, University of Rhode

Island, 142 pp.

Eenderson, J.T. 1929. Lethal Terperattres of Lamelli branchiata. Contr. Canadian Biol. N. S. 4 : 399 4 11. I 5-13 I E

Futchins, L.W.

1947. The Baco for Temperaturo Zonation in l Geographical Dintribution. Ecol. Monog. 17(3) 325-335 U.S. and

Mihursky, J.A.

1971. Upper Tc=perature I

Xennedy, Tolerances of Son.o Estuarine Bivalves.

Ches. Sci 12(4):193-204 P. 1957. Cyclo sexual de Mvtilus gfgulis L. et de M. I Lubet,callocrovincialen Ir.k dans le Basin d'Arrachon (G1.ronde). Ann Biol. 33 19-29.

Ralph, R.M.

and Henley, D.E. 1952. The Settling and Growth of Wharf-like Fauna in Port Hicholson, Wellington New Zealand. Victoria Univ. Coll., tool. Publ. No. 19:1-22. I Road, K.R.H. and Cuming K.E. 1967. Thermal Tolerance of Bivalve

Mo11uses, Modiolus_

nodiolus (L),

Mytilus gaulia (L) and Erachidentes de:nissus (Dillwyn), Comp. Biochem. Physiol. 22 (1):149-155. References for 5-6 [ Fish, J.D. 1972. The Breeding Cycle and Growth of Open Coast and Populations of Littorina

littorea, J.

Mar. Biol I Estuarine 52:1011-1019. I

Fraenkel, G.

1960. Lethal High Temperatures f or Three Marine I Invertebrates t Limulus polvuhemus_, pittorina lit _t, ore s and Pacurus loncicar:3us. Oikos 11(2)4171-182. Green, J. 1971. '1ho Biology of Estuarine Animals. University of Washington Prens; london, 401 pp. g

McDaniel, S.J.

1969. Littorin_a littorea: Lowered Heat Tolerance Inte to crvetocotyle lincua_. Exper. Parist. 25:13-15 .l R.C., Pye, V.I., and Absanullah, M. 1971. The Effect of I

Newell, TherInal-Acclimation on the Heat Tolerance of the intertidal

,l Prosobranchs, Littorina,l_itt orea (L) ctnd genodonta, lineata (DaCosta). J. Exp. Biol. 54:525-533

Wells, H.W.

1965. Maryland Records of the Gastropod, Lit _torina littorea, with a Discussion of Factors Controlling its Southern Distribution. Chesapeake Science. 6(1):38-42. I. E.E. 1972. The Growth and Distribution of Littorina l

Williams,

~ littorea (L) on a Rocky Shore in Wales. Jour. AnimaT. Ecol. 33 (3):413-432. i References for 5.] i

Annon, 1974 Report of a

Menhaden Kill in Mattituck Inlet. g Newsday, 26 Sept. 1974. i 5-14 I

Bigolow, U.B.,

cnd Schroeder, W.C. 1953. Fichea of the Gulf of Maino. U.S. Fish and Wildlife Servico, Fish Zull. b3 (4), 547 pp. deSylva, D.P. 1969. Theoretical Considerations to the Effects of Heated Effluents on Paine Fishes. In:

henkel, P.A.,

nnd g

Parker, F.L.,

(eds.). Biological Aspoets of Thermal Pollution. 5 Vandertuilt Univ. Press.

Henry, K.A.

1971. Atlantic Henhaden (provoortia tyrannus. Resottrce and Fishcry Analysis of Decline. 14 0. AA Technic.ca Report, LOTS SSRF tio. 642, 32 pp.

Highan, Y.R.,

ard Iticholson, W.R. 1974 Sexual Maturation and 1 Spawning of Atlant.ic Menhaden. Fish Bull. 63 (2) 255-271.

Hoss, et al.,

1973. (unpttblished). Ef fects of Ther:nal Shock cri Larval Estuarine Fish - Ecological Implications with resp ct to Entrainment in River Plant Cooling Systems.

icwis, R.M.,

and Hettloc, W.F. 1968. Effect of Temperature and Salinity on the Survival of Young Atlantic Menhaden (g;3voortia tyrannus). 'trans. Ar.er. Fish. Soc. 97 (4) : 344-349. 1 tiOAA, 1964. Current Fisheries Stat. lio. 3773, pp. 6-7. References for 5.0 ,s ~

Berry, R.J.,

Shila, S.B. and Horton, D.B. 1965. Growth Studies j of Winter Flounder, _Ppeudochuronectes americanus (Walbaum) in Rhode Island. Trans Amer. Fish. Soc. 94 (3) : 259-264. j

Bigelow, H.B.,

and Schroeder, W.C. 1953. Fishes of the Gulf of r Maine. U.S. Fish & Wildlife Service. Fish. Bull. 53 (4) : 577 pp. 1

Gift, J.J., and Westman, J.R.

1971. Ecsponses of Some Istuarine ) Fishes to increasing Thermal Gradients. Dept. of Environmental Resources. Rutgers University,154 pp.

Hoff, J.G.,

and Westman, J.R. 1966. The Temperature Tolerances of 3 Species of Marine Fishes. J, of Mar. Res. 24 (2) : 131-140. Buntsman, A.G., and

Sparks, M.I.

1924. Lilniting Factors for Marino Animals: Relative Resistance to Righ Temperatures. i Contro. Can. Biol. Fish.11S 2 (6) :97-114.

Pearcy, W.G.

1962. 1:.cology of an Estuarine Population of Winter Flounder,,PJeudcoleuronectes pericanus Bull. Bingh. Ocg. Coll. 18 (1) :1-78.

Poole, J.C.

1969. A Study of Winter Flounder Mortality Rates in Great South Bay,14ew York. Trans. Amer. Fish. Soc 98 (4) : 611-616. I

Topp, R.W.

1968. An estimate of Fecundity of Wi.nter Flounder, Pseudooleuronecten americanus. J. Fish Res. Bd., Canada. 25: 1299-1302. i I 5-15 am 5

JLef erencen for S.9

Digelow, H.B.

and Schred er, W.C. 1953. Fishes of the Gulf of Maine. U.S. Fish and Y'hdlife Service, Fish Bull 53 (4) : 577 pp.

deSylva, D.P. 1969: Theoretical Considerations of the Effccts of Heated Ef 2luents on Parine Fishes. Inst. of Marine

Sciences, U.

of Riami, Fla. 56 pp. Peferences for 5.10 ~

Bigelow, H.B.

ard Schroeder, W.C. 1953. Finhen of the Gulf of Faine. U.S. Fish and Wildlif e Service, Fish Dull. 53 (4) :577 pp. Gr een, J.M. and Farwell, M. 1971. Winter Habits of t.he Cunner t i Tautocolabrus ab r.?rsus (Wa1.baum 1792), in Newfound 3 and. Canadian J. Zool. 4 9 (12) : 14 97-14 9 9. I

Kinne, O.,

Ed. 1969. Marine

Ecology, "A

Comprehensive, Integrated Treatice on Life in Oceans and Coastal Waters." Wi. ley-Interscience, London. 681 pp. Peferences for 5.12

Austin, A.H., Di ckinson, J. and Hickey, C.

1973. An Ecological Study of the Ichthyofauna at the Northport Power

Station, Long Island, New York.

Long Island Lighting Company, 248 pp.

Bayliff, W.H.

19EO. The Life History of the Silverside lienidia menidia. Chesapeake Biological Laboratory. Publ. No. 90, 27 pp. Gift, J.J. and Westran, J.R. 1971. Responses of come Estuarine Fishes to Increasing Thermal Gradients. Dept. of Environmental Resources. Rutgers University, 154 pp.

Hoff, J.G.

and Westman, J.R. 1966. The Teg)erature Tolerances of Three Species at Marine Fishes. Journal of Marine Research 24 (2) : 131-140. 5-16 ---___~~~---_---_-._-.____-n_____.

I SECTION 6 IMPACT ASSESSME!."f l, 6.1 PROCEDUFIS ICR ASSESSME!;T OF THE POWER STATIO!i'S EITECi g O!i SELEC7"D SPECIES E i i 1 Impact to each of the selected species is assessed by the following strategy: Data collected from ecological studies at the Pilgrim site are E reviewed with respect to the operating history of Unit 1 (Sne 5 Appendix 73 for listing of field and laboratory studies). The density of each of the selected species entrained, entrapped, or a otherwise affacted by the thermal component of the discharge or 5 ple.t shutdown is then compared with availablo estinatos of species population densities. Infor: nation on life

history, geographic distribution, and the r:.a1 sensitivity is also considered to assess the sensitivity of the species population to I

any effect of power station operation. Predictiont. of the eff ects of Units 1 and 2 cc:-lined are made for the thermal plume, E entrairrent and entrapment for all representative species based 5 on these considerations. Analysec of impact are also based on hydrographic information 'provided in Section 2. Pertinent hydrographic information i.ncludes: (1) estinates of the maximum size or the thermal plume contacting the bottom (for assessment of potential ther:tal effects for benthic species). The offects of the ms.inum mid-depth and surface plume are also considered for assessment of impact on pelagic species. (2) the projected maxir:um intake tiow 3 2 :ombined (for assessinent of entrairment and 5 for Units 1 are entrhpment 1: ,,ct s). A quantitative prediction of impact is presented for representative species judged to potentially sustain some mortality from plant operation. The particular rnodel used for prediction depends upon the information available to quantity the i population and the information available to quantify the 3 perturbation. The models presented below are used for the quantitative predictions. Populations Ior which the age specific mortalities and i fecundities are estimated, can be simulated by a computerization of the Leslie (1945) model. This model is: U +1 N ( t t, I e-, 1 5

t where N is a 1-by-x vector corresponding to the numbe; of organism (ni) in each of x life stages, and each life stage has [ an equal development ti:no W it n g (2) 1 n ?. x The x-by-x A matri:<. is the projection matrix which describes the transition of the popalation from time t to t+1 A. F T 1-1 (3) 1 2 P, O ,_O O OP2 _0 0 I OO _O O I o O,______ ,_P _1 0 I x where h ri is the number of f emale of f spring born to a female of 3 age 1, 'n Pi is the probability that an organism of age x will survive g to age x+1, -d Pg=o f, ga) where is the instantaneous death rate of organisms of age 1. di The finite rate of population growth (R) is calculated from the h matrix as the maximum cl.aracteristic root of the characteristic equation with the stable age dictribution represented as the characteristic vector accompanying the largest root (Leslie, 1945). R = mhx char rect 3 (5) The instantaneous population growth rate (r) is: i 6-2

r = log R (6) g C*ne method of invostiga ting impa ct attributable to the power station is to estfrate the elements of the A matrix from field E, and literature values for the af f ected population. The value of W i r can then be calculated. The Pi or the probabilir.ie s of survival to the next age can then be converted to instantaneous 3 age-specific death rates. The instantaneous mortality rate due 5 to entrainment can be added to the age-specific death rate and the new instantaneous death rates converted to a new age-specific probability of survivorship. The maximum characteristic root and the associated characteristic vector of the se cond 6 matrix represent the instantaneous population growth rate and the stuble age distribution of the impacted population. Instantaneous rates of population growth with and without entrainment can be compared as can the stable age distributions. 3 This represents comparison of the theoretical potential of the g population under the assumptions of exponential growth and is therefore most conservative as there is no density dependence in the population. A computer program, EIGE!TPOP (Stone

Webster, 1975),

was developed to numerically solve the characteristic roots and vector. This program is based on the EISPAC routines contained in Reinsch and hilkinson (1971). The analysis of the year-to-year variation in population site is l made by si:ulating the population repres ented by the Leslie (1943) model. A computer program (POPI) (Stone G Webster, 1975) was also d evelop ed which simulates the Leslie model. This progra.m calculates the probability of survivorship to the next age as the ecmbination of the instantaneous rates of

natural,

fishing, and power station-related mortality.

Any of the i ele.ments in the A matrix can be constants or functions of the A population density. The population is then simulated with and 3 without the effect of the power station. The change in 3 3 population size or any selected populatzon parameter represents I the impact associated with the power station on fish eggs and larvae. l The population methods presented thusfar require a great deal of inforration for the af fected population. Because of the nature of these parameters, it is difficult to estimate them for field studies, and many times they do not exist in the literature. A simplistic approach is to translate the number of organisms lost 3 into the number of adults that would have resulted assuming no g compensatory mec hanisms (e.g., d ensity-dependent parameters) in the population. I If the populatica is in e quilibrium, in one generation the fecundity of a breeding pair will be reduced to 2 breeding adults. 2u s.y (7) I 6-3 i I

T where l S is the survival f rom egg to adult, F is the fecundity of a breeding pair during their life, 5 or S = 2/7 (B) If the affected life stage is larvae, then the survival from egg to larvae (Se)- is multiplied by I to give the survivorship from I larvae to adult (51). 8 =2 (9) S = 1 S-SI g e The nurter of affected larvae (N ) is multiplied by S to give 1 the nurler of adults (Na) that would have resulted, assuming no I density dependence. Na"SN1 (10) 1 I The nur.ber or adults can then be compared to some ref erence such as catch statistics f or co:mnercial or sport species. This is me a .gful compa.rison when sufficient information 13 not I ava; ele for the more extensive analysis. 6.2 IRISH MCSS (CHOCP.US CF,ISPUS) Irish moss is a subtidal sp.,ies occurring from rean low water to about 30 feet belcw mean low water. It is, therefore, exposed to temperature fluctuations but not to the degree of intertidal species. The primary ststion-related i:rpact to Irish moss could 3 result from the thermal plume because it is a sessile organism, h F_ntrainment may occur, altaough Chondrus does not have buoyant 5 spores. Impact assessment for Units 1 and 2 cor.bined can best be determined by looking at the historical data from Unit 1. 6.2.1 Thermal Plume Several studies have been conducted to determine the inpact of station operation of Pilgrim Unit 1 on the local Irish moss population. These include investigations of commercial harvest and effort, tenthic monitoring studies, and short-term intensive surveys reported by Soston Edison Company. The co:nnercial harvest of Irish moss declined in the vicinity of the t;ation in 1973 (Table 6-1). The effort expended also decreased, since low total harvest was prirarily caused by low density of Irish ross. This reported decrease in the harvest and offort also occurred in areas outside the influence of the station operation (una f f ected areas). Therefore, cffected and 6 - 14

.m..- 4. 2 m._ a._ o_ _x. I I I N e e e a e e e e e s 6 e N o t* e e e m t,* . P N ** va P= c P J es s 9*,

• • N
• Pt N N
• Pe p

co<meno-e m o e e e e e e e e see Fh e4**

• O M m O N O

m 9 4

• a m e t C on 4

s*

• • $* en se e ** m e P

k no+e4Nes n g r1 e e o e e e e e o e em N N ct

• Wi m on N P=

w 9 M W 9 O O E ** & F to f * ** 8* N N Pe N N f* N GC W P* p N

• W P* W P 8"e P 8'e

\\, g es-e e e e e e e 4 aO en be e N d M **P e (1 O m a es o 0 g

• se 1 ans N ** ** tw *e 94 M N N

ed 94 Le e os s P a Pm te @

• F D

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• • Q 9

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• 5

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• • 8*

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• PS er e P $ M M

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• • J o g* W M O M M

N P* P* e er' m* M GD @ f P se M ind P me e em ese N P. L O.i O + s e v e c y N e e. og pg 4 y i H H e4 p e, M Pe 4 m P= d P e e w e= e e e e e e e e y g M m m.9 m d O p e w Q bg et ce v n e e u v P* a " o e F, ga

• e e *
• W p

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• e m e n m e= N

= h l 6 9NMNfNN f. r. e e o e e e L. 19 @# # O e P* N U I ( O O s* er N P J M PG we G, ep.-, 5. h ene**WmC 9 l t m aeesee a es l P= e o e e e o e A I G. T e e e,enen e

• N 3

e n N s l ~ r~, OeVO4902 4 4 N ereNe@WGm P= e e o e o e e a e .t, man n o n. e e n m. e m-e n N P P- = e* es e k 1 r,. a c N e + n e m e 4. ~~~~ ~ 8* d O Pm N Po P P* W 8 M e e e o e o e e a P NS@PN@ WM P P* P N 3 M e' #9 M i l "1 l l 4 l 4 9 N M e f 4 Pm G m 1 4 l 1 I I E t O 5

unaffected areas were c apared to determine station eifects I (rigure 6-1). Total harvest and of fort decreased in 1973 at the station intake and discharge when co. pared to Manomet Point (unaffected area) (Figure 6-2).

However, this trend continued through 1974 when I

the station was not operating and the total harvest was high. The same annual trend was observed when comparing another control area, Warren Cove, to Manomet Point. In

addition, at a

site adjacent to the diccharge area (Rocky Point), there was no decrease until 1974 when the station was not operating. These decrease in comparisons indicate that although there won a I harvest at the station, a decrease also occurred in areas not ditectly influenced by the station. Therefore, plant operation is not considered a contributing f actor resulting 1.n lower Irish ross densities. Irish ross density (dry weight /S) in benthic studies, collected Loth preoperationally and postoperationally, have not indicated a power statien erfect. An additional intensive short-term survey, conducted in 1973 and 1974, has indicated that the quality of Irish moss is decreasing in both control and i.mpact aree.s f rom Karren Cove to Mancmet Point. There was no noticeable dif'crence I in size, weight, and condition of Irish moss betwo ~ n control and discharge arean except at the end of the discharge canal where Chondrus was absent from an area with a 50-fcot radius. Since there has been little difference in Irish Loss density at control and both the intake and discharge areas in over a year and a half of station operation, it appears that the station has not af f ected the rature plants of Irish ross. The predicted effects of the ther al plume (Appendix A) from 3 Units 1 and 2 on Irish moss are shown in Figure 6-3. The various isotherm.* are superimposed over the 10-fcot m1w contour and the distribution of Irish moss. In

summer, under conditions of highest arblent temperatures, Chonorms reproduction will be excluded from a srall area (2.1 acres) outside the discharge cans 1 based on hydrotherma.1 conditions.

Thus, Chondrus will be I excluded f rom this area.

Growth, including maximal vegetative and sporeling

growth, should be optimal in an area ot approxin.ately 6 acres during summer.

During rema ining

seasons, E

srowth should to stimulated (a110 wing for seasonal ditterences) 5 with4.n an area or approxin.ately 10 acres. Since Chondrus is a sessile organirm and is excluded f rom an area of 2 acres during one season (sunne r), it will be excluded from that uren on a I yearly basi s. Theref ore, Chondrus crowth should be stimulated for an area of approximately 8 acres. The areu observed to be devoid of Chondrus tron Unit 1 operation (50-f cot radius) will increare to a 110-foot radius with the additional of Unit 2. This represents a worst case condition of t.he cor.bined plume. This indepencent prediction of effects based 6-5 I

I

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• 9.,

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x. y

.+: n.., . s ..e.,, ., b.s.Af s%w.:n,m . i..,.,y. .. 4.n. s.1. - f (,'.fli,cRIM %,%.,.*:'.w. 6,.;mq' *.H W'q.2 A;h j., W, i< ?."."e N .,*,.*A- .,.c.M r $J TE v,* i.,'d. * ?.. C. M /+1. / k*g2L)Ll. *Ja :.g

• s

.a $$[4@h@@@h,.,3i M ' O ' 4 d h" ).&d N { hm: IY h ,.) k;.

• l3kO.k ').

t,. k / l$E % P "o.' .l' $97p3 i mi.2./. .. o g s ,,,,m ,-.v. 7s _ Y 4 C'pf,,,?.; s. '.s - r,, n; -:, ',.. - ,.*..7. Wg M c;. g., w4,. 2:e. %% , R, g y. u e.,- ^f $ If'hfhk?. ' f &' ~ A R f l & & W h ~.N,m. kn I' GA L,. I I FIGURE 6-1. IRISH MOSS HARVEST AREAS IN CAPE CDD BAY g IN VICINITY OF PILGRIM STATION l I I l l I

DISCHARGE INTAKE l.2 f.2 1.0 1.0 - 9 E \\. N \\ \\ \\, .8 .8 b \\\\ 2 .6 \\s. .6 N. 2 4 \\- e 4 g os t w '.- g = - ;s. .2 .2 '% N

c. ::. =

e i g 1971 1972 1973 1974 1971 1972 1973 1974 I -WARREN COVE ROCKY POINT I 2.6 j * *i 1.2 /

1. 2 I

I l.C 1.0-9 Eo'8 .8 D s a g g .C .6 3 f- ~ I ~- *~- I -.. \\ 4 4 o C 5.s \\\\ e s's 9 k .2 NN '.2 4 4 g L-1971 1972 1973 1974 1971 1972 1973 1974 - HARVEST RATE

---

H ARVE ST ( LB S )

-- - EFFORT (H RS)

I' FIGURE 6 2

[ COMPARISON OF ANNUAL IRISH MOSS HARVEST STATISTICS AS REL ATED I TO MANOMET POINT f a

AMBIENT

• 63*

Au!IENT *2' ,e ~# ..s SUMMER FALL 9I AM B: ENT

• 33*

AM B'ENT

• 43 '

/ ~ WINTER SPRING j, L 'N D h!! REPRODUCTION EXCLU0tD ? [f//,ff]dAXIMVW G R OWTN 'tl' [S\\S\\] Get0*TM STIMJLATED 0 2,00 1000 20,00 PRESENT IRISH W0t$ t!D ~~ ~ ~ 10'Wi.W C E PT H CQ NTOU R 1 l 2 I FIGURE 6-3 g POTENTIAL THERl,iAL PLUME EFFECTS IRISH MOSS 1 M E

on literature themal tolerance data and hydrothermal predictions is very similar to operational observations, since Chondrus was I observed to be thriving-directly outside the observed barren area, (50-foot radius) during Unit 1 operation. 6.2.2 Entrainment 1.ntrai.nment of Irish Moss spores was observed in the fall of I 1973. Thermal toirrance

tests, however, indicated that significant mortality (30 percent) of spores on passage through the station cooling system would occur only when ambiet.t water temperatures were greatest, in late summer when spore density is I

low. 6.2.3 Entrapment (Not applichble) 6.2.4 Cumulative Ircpact Most of the possible impact of station operation on Irish moss 3 should result f rom the thermal plume. This localized effect will 5 result in the elimination of Irish moss immediately adjacent to l-the discharge area (2.1 acres). No impact will result frcp entrapment, as no life stages are susceptible to entrapment. -I A.lthough entrainment can occur, thermal tolerance tests on Irish moss indicate no impact of consequence from entrainment. Station operation will result in a negligible effect on the total Irish moss population in the Warren Cove - Manomet Poi.nt area and on the ccrmercial harvest. In fact, stimulated growth adjacent to { the discharge =hy offset losses in the immediate vicinity since the area of stimulated growth is 4 times as large as the barren I area predicted. 6.3 ROC M ED (ASCOPHYLLUM PDOSUM) Asceo? ellum nodo sum is an intertidal species and therefore is nuturally exposed to Isrge temperature fluctuations. However, as an intertidal spec',es, it has a life history strategy which compensates for these fluctuations. A continuous thermal stress, however, may result in stress during reproductive periods. g A. nodosum is a sessile organism. Therefore, primary station-related impact to A. nodosum should result from the thermal plume. 1.ntrainment may occur, although the spores are probably nonbuoyant. Impact assess.nent for Units 1 and 2 combined is determined by observing the operational impact of Unit 1. I 6-6 I

6.3.1 Thermal Plume A benthic monitoring protiram in the vicinity of Pilgrian Station E has determined seasonal density for A.

podosum, both 5

preoperationally and postoperationally, at various transects (Figure 6-4). The mean intertidal densities (dry weight /m2) at Rocky Point (discharge

area, Transect G-1) and Manomet Point (unaf fected area, Transect G-5), are summarized in Figure 6-5.

The density of 3 nodosum appears to be somewhat stable from l year-to-year, with natural decreases in density occurring in spring. The densities at Rocky Point and Manomet Point were markedly simila r, preoperationally. Although the densities differed postoperationally at both locations, the pattern at RocPy Point was consistent with the preoperational trend. This suggests that there has been no detectable effect of Unit 1 g operation on Ascochyllum. g As discussed in Section 5.2, linited info mation on the the mal tolerance of Ascochv11um makes prediction of the ef fects of the combined Units 1 and 2 thermal plume difficult. The maximum plume temperature outside of the discharge canal will not reach 930F during any season. Therefore, acute mortality should not occur. t The the =al plume may have some effect during reproductive periods; however, since As cochvilum thermal tolerance during these periods has not been described, this effect is unknown. l Population density data collected both preoperationally and r postoperationally have not, however, indicated a station-related effect. b I 6.3.2 F_ntrainment Zygotes of A. nodusum are nonbou'

t and adhesive and thus are not expected to be subject to entr<.

.ent. No 3. nodosu6 =ygotes a have been col' :ted in entrainment sanples. E { 6.3.3 Entrapment Not applicable. 6.3.4 Cumulative Imphet No station impa ct on A. nodosum is expected to occur through entrapment on entrainment, since no lif e stage of this species is susceptible to these sources of 1.mpact. The only potential source of impact expected is the thermal plume. 'Ihe upper lethal temperature of A. nodosum (930 F) will not be reached in the discharge plumt; so

little, if

any, mortality is expected.

Reproductive periods occur from fall through spring when discharge temperatures are low; thererfore, no impact is expectec during these periods. 6-7 r nut

l I ,,,. t t 'a + .r. +' =,....... <..- ( .s ' - ?,- 1 1 . ' ', ; 4.. * ',, -f,,.,' .., ', -.. ',J e, } N' kI A !/ sA, I - i'. a ;.(.1, g ;*.

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. I \\ e y NOT Et Trewt Station 1 entends pe pondicular - 'to the shore line sopronimately 2 mhs

• w.

NW of hiprim Station;. p,- T 2 & T 3: TreW1 Stata ns 2 and 3 estand s I s i '. perallel to shore line along 70 and

4. foot contours (MLW). respectivety

" i ', -. E, directiv seewerd of station discherge.

G 1, G 2 G 3, G4, G$:'Trertsects.I -I .), ,t C 1/2 1 l N e ~4 ~- SOALE IN MILES I PL YMoviHan'. Lone sean 1-T3 1 I. ]T.2 rt ruourre t a.,t MAR 50M /, s ~ 'ROChyPvont 'G-2 \\'- ..wf./% / 4 ' rit' GRIM f/ S /. M'/. ,'\\ K 4 T-(. '-, 5 A\\ . A,,lT E s .,i": Tl e e i, w.n u co., l. f.3.:.. . < re. % :....

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.y . 'o .e- .s ,..?,.c% e :, ***.<# t,.. ' n.- . - :5 ~ ,s n. "p. 5 ,/* 4 -.<q". m 1 u,, a free - 11gria uwclear Preet 8tation avaterwental Report

• Catt 3 FIGURE 6-4.

Il LOCATION OF SAMPLING STATIONS 1 FOR ECOLOGICAL MONITORING PROGRAM I I I

I 100,000 N s / \\ t \\ ~ +- a g ./, \\ 's \\M /s / k / \\ H / \\ / \\ E / \\ b / / I / \\ / g a I E \\g/ n u j' 2 li jI t,000 lj l I I 1 t i I 1 1 1 f AU3 NOV FLB Maf AJG NOV FEB W AY AU3 NOV FEB W AY $[Pt 972 1973 1974 1971 l l PR EOP E RATlDN AL - OPE R ATION AL - NON-OP E R ATION AL PLUME AREA (ROOKY PolNT)

---

CONTROL ARE A (M ANOMET PolNT)

{ ) li -} i i FIGURE 6-5 MEAN INTERTIDAL ASCOPHYLLUM NODOSUM DENSITY IN. DRY WElGHT (G/M2) l 1

1 l. 6.4 MiPHIPOD (ACANTHOEAUSTORlus MILLSI) Acanthchausterius millsi is a subtidal burrowing amphipod found [ offshore of Pilgrim Station. As an offshore species, A. millsi is less subject to power station ef fects than inshore species. The component of power station impact that will most affect A. j millsi,is the thermal plume. No A millsi have been collected in i entrainment

samples, and the species is too small to be entrapped.

Impact assessment for Units 1 and 2 ccc.bined can again be determined to some degree by using the known impact of Unit 1. 6.4.1 Thermal Plu,e Results of the Unit 1 benthic surveillance study have been I reviewed (preoperationally and postoperationally) to determint the impact of station operation on A. millsi. Mean densities at q! 20 feet below mean low water (mlw) at the discharge location (Transect G-1, Figure 6-4) and White Borse Beach (control) (Transect G-4) are compared in Figure 6-6. Densities of A. h millsi are highly variable at the unuffected (White Horse Beach) -E nd discharge locations. There are several factors which may 3 contribute to this variability.

3. millsi is motile and can thus ll avoid sar:pling devices.

Also, the preferred habitat at the

~ discharge sa=pling area is somewhat limited because of the extent of rocky areas. This would also contribute to the lower density at the ef fluent station, as compared' to White Horse Seach. With reduced preferred substrate, collections at the discharge would be more subject to variability through clumping, and thus a nonuniform distribution of organisms. This type of variability cornonly occurs in short-lived univoltine

species, such as midges, found in fresh water lakes and streams.

l TLe themal plume will rarely contact the bottom in the area of 20 feet below mlw. When it does contact the

bottom, only the two-and three-degree isotherms will reach this area.

The habitat inshore of this area subject to higher temperature increases -does not appear to be suitable for A. millsi, as it is primarily a rocky substrate. The thermal tolerance of 3 millsi appears to be

high, although it is a

subtidal species. Temperatures us high as 970F are necessamr for complete mortality, and the temperature-mortality range appears to be -small (Sameoto, 1969). Theretore, no impact is

expected, since J-temperatures will not reach 970F in the two-and three-degree isotherms.

I' 6.4.2 Intrainment Ibt applicable. 6.4.3 Entrapment Not applicable. 6-8 E

I l I l\\\\ /n\\ I \\ / \\ l \\ / / \\ l \\ 10,000 / \\ g \\ l \\ l \\ \\ l \\ l \\ I \\ \\ l l \\ j \\ l \\ I \\ l I \\ l \\ \\ l \\ \\ ll y I \\ I \\ s a \\1 N, l 's 2 1,000 N \\ Di 'g /\\ \\ / \\ o \\ / \\ f t / \\ \\ / \\ s \\ / g ) / f \\ / s \\/ 100 ~ l a -i I 1 I I I I I I t I

)

AUG NOV FEB WAY AUG NOV FEB MAY AUG NOV FEB MAY SEFT 19 71 1972 1973 1974 P R E O P E R ATIO N AL --*-4 CPE R ATIONAL ---

gM-N Ob

• C P E R ATION A'.

I PLUME AR E A (ROCKY POINT) - --- CONTROL AR EA (M ANOM F.T POINT) FIGURE 6 6 MEAN DENSITY OF ACANTHCHAUSTOR/US MILLSI l AT 20 FEET BELOW MLW em 5 t

) i= 1 6.4.4 Cumulative Impact L, tb station impact on A. millsi is expected to occur through entrapment or entrainment as n i lif e stage of this species is i susceptible to scurces of in act. The only potential source of s impact is the thermal plume. The only suitable habitat for A. millsi in the discharge u ea is at 2D-foot m1w, which is beyond the major influence of the predicted thermal, plene. Therefore, there should be no impact on A millsi as a result of the 2 operation of Units 1 and 2. 6.5 AMERICAS LOSSTER moMARUS AYERICANUS) The lobster is a subtidal, mobile benthic species found offshore of the Pilcrzn Station. As an offshore species, lobster are less subject to power station effects than inshore species. Manitoring studies at the site have indicated that the local j population of lobster is not a self-sustaining population and I' relies on spawning elsewhere in Cape Cod Say. Morrisey (1971) indicated that there was some movement of egg-bearing f emales from the northeastern shore of Cape Cod to this area. Only 238 of 4,616 lobsters handled during studies through 1973 were egg-bearing f emales. Thus, the local population in the v4.cinity c: Pilgrim Station is a nonsustaining population. Impact assessment for Units 1 and 2 is determined relative to g data on the i= pact of Unit 1 on the lobster. 6.5.1 Thermal Plume Two monitoring studies have been conducted preoperationally and I postoperationaly to determine the impact of station operation on I lobster. A harvest per pot study monitored lobster catch within grid areas (Figure 6-7) in the vicinity of the station. Figure 6-8 shows the catch per pot for grids in the discharge area and catch per pot at Manomet Point (control area). There is little difference between the catch per pot at areas, both pr eoperationally, operationally, and seasonally, indicating no power station effect. Generally, a greater total catch occurred in the dischurge crea although it is not reflected in Figure 6-8. Additionally, the effort (number of pots checked) Increased with the season. m A second study onitored lobster migration in control and affected areas. The discharge area did not seem to present an unranageable stress on lobster, as the patterns of migration were similar from Rocky Point (discharge area) and Manomet Point (control area). I The seasonal ef f ects of the predicted thermal plume (Appendix A) from Units 1 and 2 are shown on Figure 6-9. Based on therma} I tolerance data ior lobster (Appendix A), permanent resicence of adult and juveniles will be excluded f rom the ar ea (2.1 acres) i 6-9 E

c / .l J 4 0 9 l 3 C f 6 l f g c S /g V ti l j';' N >.q. .. Ly * + ~,.. g. h: ~ O ', g.. -.[l::x [. .. *j , ~. 1 .y f l -- p g_ r

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13

~.L2it ' nF4 x 4 y p ,7 4 : .-SCALE - MILES ~ -t s' I FIGUR E 6-7 LOBSTER POT SAMPLING GRID I E

~ l '8 1972 1 12 n PREOPER ATION AL se S g% i s / 7 / I e- / 5 /' /' I 3 s # -~~~ ~ I i C l 1973 I ' * ~ CPERATIONAL 13 12 - si I 10 y ', c: e 5. /- I e 5; , - ( 5, =3 e 1974 N O N-O PER ATION AL OPERATIONAL

l

s l ) 12 11 i: t, S 3 I 7 4 j 5 t $~ 1 I I, 1 I

l. _,

i

.o is ic as

ic s ra r>

s io.s.v as e is ra ts s e o ac ts io is ta as a e is cc as a ic is ar, as uam:s Apait war suNE Juty Aucust stPTtwett ocicetn PLUME AREA (GRIOS H il.12 S 1-11,12) --- CONTROL AREA (GRIDS G-II.12) ,I I FIGURE 68 MEAN LOBSTER CATCH PER POT I l

I 1 AMBIENT

• 63 AMBIENT
• S2' s

67 (

. y os ] u y I

r SUMMER FALL i 1 AMSIENT*33* AVB:ENT*45* N w /

• s s

'N s = WINTER SPRING j LEGEND h 4 WCRTAUTY ( ADULT $ 4 LARyAE) K\\MjoaTiuuu cao*'in (Aovtts e tanvar)

---

!o' utw orp TH couroun o

500 1000 to,oo l scatt-r ecT 1 1 I I FIGURE 6-9 POTENTIAL THERMAL PLUME EFFECTS LOBSTER ,I Oil

l I t immediately adjacent to the discharge canal during the su:mer months. The urea immed$ately outside this exclusion area will I maintain temperatures ( 6 8-77 0F) allowing maximum growth for / adults and juveniles during the su =er months. During the other

seasons, the temperature should be stimulatory for increased growth in the su cer exclusion area (154egree isotherm).

Growth I-of lobster to harvestable sire has been shown to be reduced f rom seven to two years in some heated waters (Eughes et al.. 1972). I Lobster are mobile and can thus migrate to the thermal plume when temperatures are suitable and migrate out of the thermal plure if temperatures are less than optimal. m 6.5.2 Entrainment I lobster larvae huve been collected in the vicinity of I Although the station, they have not been collected in entrainment samples at Unit 1. This ray be attributed to techniques used for lobster larve collection in entrainment renitoring or that the larvae are not subject to e.trairment. F.ntrainment effects will therefore be based on densities of lobster larvae collected near the i station and thus represent conservative estimates of entrained larvae. Lobster larvae are sparsely distributed and congregate at the surface (Personal communication, R. Fairbanks). Two I water separate collections were conducted in 1974 resulting in s mean density of 0.95 larvae /1,000 cubic meters f rom June-August, and a mean of 2.9 6 larvae /1,000 cubic meters from J une-July. For purposes of entrapolating potential entrainment etfects the more conservative (2.9 6 lurvoe/1,000 cubic meters) was used. i number of individuals not attaining adulthood cue to larval I The entrainment can be calculated using the density of larvae colle cted near the station, the calculated flow through Units 1 and 2, and known fecundity vulues. The depth of the vuter column at which these col.'. e ctions were made is approximately three meters. Therefore, to make the clumped distribution (Stage 4 I larvae clumping at water surf ace) fit a uniform distribution, th e I distribuiton was culculated to be 0.99/1,000 cubic meters for the total water column. t 2.96 larvae /1,000m3 3 meters = 0.99 larvae /1,000m3 The number of larvae potentially entrained per year was calculuted by the following equation: 0.99 larvae /1,000m3 x 30 days (period of occurrence) x 6.87 i x 106 m3/ day ( 2 -unit intake volume) = 204 x 102 larvae / year Assumir.g 100 percent mortality on passage through the station and using a mortality factor of 99 percent from eggs to Stage 4

larvae, this re sults in the e cuivalent of 2.03 x 105 eggs I

entrained per year. An estimate of loss of ha rve stable adults 6-10

(Ma, Section 6.1) can be made based on average harvest sire (1.2 lb) And fecundity (10,000 eggs / female) for this year class (Saila et al., 1969). g -} W N =204 x 105 eggs / year x 10-* female / egg x 2 = 4080 adults / year a Theoretically, the number of harvestable lobster lost with 100 percent mortality through the station would be between 2640 and 4080 lobster / year, based on the results of the two studies. This represents between 0.4 and 0.6 percent of the average yearly E I harvest of lobster for Plymouth County (Eeals et al., 1970). 5 These estichtes represent very conserv: tive estimates as lobster larvae have no+' been observed in entratament collections. 6.5.3 Entrapatnt ~ } To date, no lobsters have been collected on intake screens during Unit 1 operation. Lobster entrapment is not expected to result in the future because of low intake velocities (less than 1 fps for both units). 6.5.4 Cumulative Impact to station impact on lobtter is expected to occur through entrapment as intake veloc. ties are low. Potential station effects on lobster can result from the thermal plume and entrauunent. Based on thermal tolerances, during the summer

months, adult and juvenile lobsters will t'

excluded from 2.1 acres i.mmediately adjacent to the dischar p canal. During the rest of the year, growth should be et aulatory within this area. Since lobsters could avoid less tY optimal temperatures, no mortality as a result of the predicted thermal plume is expected. Although no larvae have been observed in entrainment monitoring tor Unit 1, the potential for loss of' larvae through entrainment exists. Based on nearfield larval densities in Cape Cod say, as many as 2.04 x 106 larvae could be entrained per year. Assuming 100 percent mortality on passage through the station, this could 33 result in the loss of 4080 harvestable adults per year or 0.6 percent of the Plymouth County unnual harvest. Based on these predictions, the effect of the operation of Units 1 and 2 on the. lobster population of Cape Cod bay will be negligible. I 6.6 MUSSEL (MYTILUS F.DULIS) m ,i Mytilus edulis is adapted to many environmental conditions, 3 including varying temperatures and exposure to partial drying. E i Station impact would result from the thermal plume on adult organisms and entrainment of planktonic larvae. Potential impact 6-11 I w

l of Units 1 and 2 is assessed using the known impuct of Unit 1 on M. edulis. 6.6.1 Thermal Plune A station-related benthic monitoring program has determined l preoperational and postoperational seasonal mussel concentrations. Figure 6-10 indicates the density of Mytilus or I M. edulis intertidally at Rocky Point (discharge area) and j Hanomet Point (unaf f ected area). Intertidal densities are I

analyzed, as the greatest densities of Mytilus occurred intertidally.

1 Although the populations fluctuated over time at both Rocky Point g and Panomet Point, there was a gradual increase. In g ene ral, g there was no detectable difference between preoperational and operational densities, except in August 1971 and Febzu ry 1974. both cases, the station was not operating; so they are not the mit of station-related ef f ects. Mvtilus was more abundant at cky Point than at Manomet Point. Perefore, there appears to be no effect of Unit 1 operation on Ms cilus populations. The seasonal effects (based on Appendix A) at the predicted thermal plume from Units 1 and 2 are shown in Figure 6-11. The greatest density of Mytilus occurs within the 10-foot mlw contour I shown. A higher ambient te=perature (me m seasonal surface temperature) is used in the diser of nytilus than the previous sub-tidal species to be m resentative of the c intertidal environment. Under conditio... of maxi: um ambiest temperature (summer season), the thermal plume may result in some mortality within the 15--degree isother= (2.1 acres) as was the I case for lobster sub-tidal species. In addition, during maximum ambient temperatures (summer), temperatures in an area of 10 acres may result in cessation of f eeding in Mvtilus. At the edge of the p i.ume, temperuture conditions will be optimum for I settling of larvac. It is assumed then that larvae (veld ger or pediveliger) will settle in the outer edges of the thermal plure. In the f all, the areas for maximum settling will be closer to the discharge, and f eeding could be ceasec in the immediate discharge 7 area (1 acre). In winter and spring, settling could still occur within the 10-degree isotherm. It appears that the station will result in a localized plume ef fect of yearly population shif ts of Mvtilus inshore in winter I and offshore in su=ner. 6.6.2 Entrainmen t i Bivalve veliger larvac have been collected in entrainment sar:ples /. at Unit 1 for a period of 210 days from Apri'. to No. ember (1970). During this perio d,

however, most bivalve larvae were not i

6-12

E i m.oco 1 20,000 1 10,000 / \\ 1 / \\ s \\ g s 000 /g \\ [s = / \\ g\\ l \\ E \\/ l \\ t i s e / V 1 f O

• s

~ \\ / g f I o z s / g i h# ] \\ l .t \\ g \\ l l see g I t \\ l ( \\! l t l\\l i t i i e i i t i ,33 Avo s:v rEe uAv Ax Nov FEa uAt Avo Nov FEs uAv stPT 1971 1972 1973 4974 ', ] I I P RE0p ! E ATION A L C8E R AT IONAL

; - NO N* 0P E RATION A'.

1 } PLUME AR E A (ROCKY POINT) -- -- CONTROL ARE A (M ANOMET POINT) I 1 : i f lI lI} nGURE 6 10 MEAN INTERTIDAL MVT/l.US DENSITY Eg l *i 1 B l

I AMBIENT

• ES' AM BIENT
• 60*

.t 4 M[CRA. b . h76b..bh G <p, [fW?'kRs#., ft 'N s s /s,f/,lMW//it:p,,, 7~

f. v..,,s.k"9 l &,,,~, s.' }.!,,

.t, I l' l.- 'T;~ ' f.,' % '~ ~ ~~~ i ? f.. Yi f 83 k3 I i = [ t SUMMER FALL i ~ l I AV BtENT

• 43' AVB!ENT* 54*

l ~wg.m....:. :w:..... x s I l 5'i ' ,I: '. : u .s

l,tj:::.;;d p(

L [ $i?iij!!ii.$. (/ / f f a WINTER SPRING I ~ I LEGENO l; - ] MORTALITY l\\\\\\hssj Cl3 SAT 10N OF F!!!!NG ['W///i SETTLING PCDU;to 0 $00 1000 2000 t. i SO AL E - F E CT ll? ' % j $C'TLINC QPTIONAL L- % SPAwNiN3 iNITIATro

---

10'MLw CEPTH ccNToum g

K I s i F"iURE 6 il y POTENTIAL THERMAL PLUME EFFECTS I MUSSEL l h I

)l I I identified to species. The estima ted a.nnual number of bivalve larvae entrained in Unit 1 is: ,l i 1632 larvae /m3 (mean number per sample) x 210 days x 1.8 x 106 m3/ day = 6.17 x 1011 larvae / year j To extrapolate the effects of two-unit operation, this estimate was multiplied by the ratio of the flow for Units 1 and 2 to the flow of Unit 1 (3.75). The maximum annual number, based on the 4 l projected flow through Units 1 and 2

combined, would be 2.31 x 1012 larvae entrained.

This estimate assumes that all bivalve larvao collected are Hvtilus and is, therefore, highly conservative. Additionally, entrainment mortality studies at Unit 1 have l indicated 80 percent survival of bivalve larvae on passage a through the staticn. This conservative estimate of larval loss is used to extrapolate !i to adult loss. .h Purchon (1968) indicated that mortality over 99.9 percent was i normally compensated for by bivalves in general. Applying this 3 assurption to

Mytilus, the entrained larvae might produce 2.31 x 10$ adults.

The average density of adult Mytilus for all stations and all seasons !.s 4,700 organisms / square meter. Therefore, the equivalent of 4.9 x 105 square meters or 121 acres could theoretically be devoid of Mytilus. [ Theoretically, the equivalent of 6.17 x 10s adults or 32 acres 5 should be devoid as a result of Unit 1 operation, when in reality no detectable change in gutilus density at the station has occurred as a result af Unit 1 operation. Based on low mortality of larvae on passage through Unit 1, the f act that all bivalve larvae are ussumed to be Mvtilis and the negligible effect of E entrainment resulting in adult population decreases at Unit 1, E h the estinate of 2.31 x 105 adults / year lost is extremely 'l conservative. gg. 6.6.3 Entrapment Mussels are commonly collected from intake screens; however, they are not considered entrappec species since they a tively colonize [ the screens rather than being passively swept onto them. 6.6.4 Cumulative Impact i i No detrimental station impact on !i. edulis is expected to occur E through entrapnent as this species readily colonizes intake g screens. However, potential station-related effects on 0,. edulis j can result from the thermal plume und entrainment. E' 6-13 E en ~ E

Based on thermal tolerances, some mortality will occur within the 15 -degree isothern (2 1 acres). In

addition, during brief periods in the

sunser, muss els within an area of 10 acres adjacent to the discharee canal ray cease feeding.

This will probably not result in mortality. During the other seasons, the tet::peratures within these areas will be optimal for larval

settling, i

r.ntrainment of g. edulis larvae will occur through Units 1 and 2. l The predicted number of larvae entrained is 2.31 x 1012 larvee per year based on entrainment monitoring at Unit 1 and the combined Unit 1 and 2 flow. A conservative estimate of the ( acreage of adult loss through larval entrainment norta]ity j (assumed to be 100 percent) is 121 acres. A more reasonable and B yet conservative estirate of adult acre-;c loss (based on the effects of Unit 1 operation and preliminary entrainment mortality studies) is 20 percent of the aoove estimate or 24 acr e s. ,I Based on the above estimates, the large area of Cape Cod say, and rapid coloniza tion of M. g.ulis, the cumulative impact of Unit 1 And 2 operation.on the Cape Cod Bay population of M. edulis (approximately 26 acres) will be negligiblo. 4 II s L. 3 1 h I i 6-14 8

6.7 COMMON PERlHINKLE (Ln'rORD@ LTTPOREA) Com:non periwinkle is a dominant intertidal gastropod at Pilgrim Station. It is a tolerant. organism adapted to varying temperatures and partial drying. Power station-related impact could result from the effect of the thermal plume on adults and entrainment of planktonic egas and larvae. As in previous 3 discussions, the potential irpacts of the combined Units 1 and 2 5 discharge are described by relating results of monitoring studies at Unit 1 to the predicted Units 1 and 2 discharge data. 6.7.1 Thermal Plume A preoperational and postoperational benthic monitoring program l has indicated trends in seasonal perivinkle densities. Figure 6-12 indicanes the density of L. littorea intertidally at Rock Point (discharge

area, Transect G-1) and Manomet Point control

area, Transect G-5).

Intertidal densitics are analyzed as the greatest densities of Littorina occurred intertidally. Figure 6-12 indicates that the Littorina population of Manomet Point is more stable over time than at Rock Point. There is a decline in population size ac Rock Point from 1971 to 1973. It is unlikely that this is attributable to power station operation since this trend continued when the station was not operating. The seasonal effects of the combined thermal pluke based on a E temperature tolerance -(Appendix A) of Units 1 and 2 on Littorina E are shown in Figure 6-13. The greatest density of L. littorea occurs within the 10-foot mlw contours shown. During maximum ambient temperature (su=:cer), come mortality may occur within the j 15-degree isotherm. 6.7.2 Entrainment Gastropod eggs and larvae have been collected in entrainment collections for Unit 1 -during 1974. Littorima eggs were collected from April through August and Icevae were collected from July through November. During these periods most gastropod larvae were not identified to species. Therefore, all gastropod larvae entrained were assumed to be -L. littorea. The annual number of Littod ga_ eggs entrained in Units 1 and 2, based on 1 Unit 1 collections a.,d. projected flow rates, are: 282.7 eggs /m3 x 140 days (period of occurrence) x G.87 x 106 m3/ day = 2.72 x 1011 eggs / year The annual number of larvae entrained is: 180.3 larvae /m3 x 126 days x 6.87 >. 106 m3/ day = 1.56 x 1011 larvae / year i l l 6-15 I 4 E

il ic ece i I 1 I 10.SO / \\ g / \\ / \\ f v N,, N ,/ s, p, x N f' \\' \\ / \\ I j O \\ / \\ 5 V \\ \\ \\ \\., 10 0 'I i !I i ge L a i i AJ3 NOV FEB WA. AUG NOV FEB u t.Y AJG NOV ([B M A1 $[PT 1971 1972 1973 i i ceca s. ties AL ,-.- Nos.octaaricu t.t ententa 4 tics AL ,I PLUME ARCA (ROCKY POINT) [

---

CONTROL ARE A (M ANCMET PolNT)

E I FIGURE 6 12 } ME AN INTERTIDAL DENSITY OF l.lTTORINA LITTOREA (NO.PER M 2) I

Ausigur. es' Au siENT= 52' l ~f % /O ,.Q s / 1 T J @y "j@f s l SUMMER FALL II I g ,u e, Es1. n. 4..Es1 4.- !r%- e!(,:~/y. 1 'O; f D'Y i \\ a ,1 t a y a t cy i WINTER SPRINu A I LEGEND h WORTALITY ---10' W LW C EPT H CO NTOUR 0 $00 1000 2000 SCALE-FEET a i l l} FIGURE 6-13 POTENTIAL THERMAL PLUME EFFECTS PERlWINKLE i

..... r - ; n - o The projected ntr.ber of larvae entrained is high in relation to l the egg density. This could be due to high survivorship from egg to larvae (in this case, 57 percent), which is unlikely. A more r:asonable explanation is that the veliger larvae collected at l the station may not be from the immediate station area as the In:vae are planktonic for a 6-week period, while the eggs are in the water column for only 6 days. The larvae could thus be from area. To represent a conservative estimate of i . an extendt.d locali:.ed impact, the larval number entrained will be included in aasessing i.mpact. Assuming a 0.1 survivorship of eggs to larvae, a total of 1.83 x 1011 larvae would be entrained per year (2.72 x I 1010 + 1.56 x 1011 = 1.83 x 1011 larvae / year). This conservative estimate of larval loss is used to extrapolate to adults. Purchen (1968) indicated that mortality of scrne molluscans of over 99.9 percent was normally compensated for in general. With this assumption applied to L.

Jittorea, the entrained eggs and larvae might produce 1.83 x 10e adults.

The i average density,of adults for all stations at which L. littorea occurs is approximately 400 organisms per square meter. l Trerefore, the equivalent of 4.58 x 105 square meters or approximately 113 acres could theoretically be devoid of

[

Littorina. This estimate is probably very conservative as the operation of Unit 1 would have presumably affected the populations at P.anomet Point to some degree, but there was no noticeable effect in postoperational

studies, all gastropod l

larvae were assumed to be L. littorea, and better than 80 percent survivorship of entrained gastropod larvae was observed (Section 6.6.2). 6.7.? Entrapment Ibt Applicable 6.7.4 Cumulative I= pact L. littorea is expected to occur t}zough No station impact on I entrapment as no life stage of this species is susceptible to E this source of impact. Potential station-related effects on L. littorea can result from the thermal plu=e and pri.marily entrainment. Based on thermal tolerances, twenty percent mortality will occur in the su=mer within the 15-degree isotherm (2.1 acres). Entrainment of both perivinkle eggs and larvae will occur tFrough Units 1 and 2. Based on entrainment monitoring at Unit 1 and the combined Unit 1 and 2

flow, 2.7 x 102i eggs and 1.56 x 1011 larvae per year will be entrained.

A conservative estimate of the acreage adult loss through entrainrent mortality (100 %) is 113 acres. A more reasonable and yet conservati.ve estimate of adult acreage loss (based on the ef fects of Unit 1 operation and preliminary entrainment mortality studies) is 20 percent of the above estimate or 23 acres. 6-16

!I j Based on the above conservative estimates, the large area of Cape l Cod Bay, and rapid colonization of L. J_ittorea the cnnnulative impact of Unit 1 and 2 operation on the Cape Cod P,ay population of L. littorea (approximately 25 acres) will be negligible. ) 6.8 ATIANTIC MENiMEN (BREVOOKTIA WRAU!MS) } The effect of the operation of Units 1 and 2 on the Atlantic menhaden (Brevoortia tyrannus) population is predicted by a population simulation model. Sources of impact to 'his g population include entrainment of

larvae, impingement of 3

l yearlings and the effects of the thermal plume, such as gas bubble disease to adults. The basis for the analysis of i:apact is a population dynamics simulation model initially developed by Schaaf and Huntsman (1972). The model was used to simulate menhaden populations for a 50 -year period. The analysis also included additional sources of mortality representing the power station operation effects. Results of both simulations were compared with respect to population size and the projected yield to the com:aercial f 4 shery. g i R 6.8.1 The Model The menhaden life cycle model used fcr this analysis allows prediction of future popuistion strveture. A Ricker (1958) stock i and recruitment f unctior rom Schakf and Huntsman (1972) was used to predict the number of fish in age-class I (R) from the total nu=ber of spawners (S) the previous year: 1' R = S exp (1626 - S/106)/654 (1) I-The stock and recruitzent function is the density -dependent l component in this population dynamics model. A graph of the g function is depicted in Figure 5--14. For spawning densities g .[ below 6.54 x 105, an increase in the spawni.ng stock results in an Q increased number of recruits. For spawning densities above l 6.54 x 10s, an increase' in the spawning stock results in a decreased number of recruits. 5 lt. !$j* The instantaneous natural mortality and fishing mortality were g l. assumed to be constant for all ten age-classes. The E instantaneous fishing mortality of age-class I was calculated as 'I 66 percent of the fishing mortality of the other ages (Table 6-2). The simulations were run with a natural mortality i; rate of 0.37, as developed by Schaaf and Huntsman (1972). The instantanecus fishing mortality rate of 0.8 was used. Schaaf and Hunten (1972) determined that this fishing mortality rate l results in annual commercial catches of 400,000 to 500,000 metric 5 tons. j Yield to the commercial fishery was calculated using the j exploitation for=ula: 6-17 I ~ d 5

TAnLE 6-2 - PAFAMETERS OF T10:. MENEADEN POPULATION SIMULATION MODEL l Initial Instantaneous Instantaneous Average Age-Population Natural Fishing Weight Class Size (x106) Mortality Mortality (crams) Fecundity [ 1 1,480 0.37 0.53 115.60 ( 2 1,472 0.37 0.80 245.61 3 363 0.37 0.80 406.96 239,845 4 493 0.37 0.80 545.04 345,976 5 69 0.37 0.80 625.73 408,269 6 15 0.37 0.80 691 69 459,237 7 3 0.37 0.80 720.56 4B1,330 ( 8 1 0.37 0.80 762.24 513,420 9 1 0-.37 0.80 762.24 513,420 10 1 0.37 0.80 762.24 513,420 ( l i I I l l l 1 l 1 of 1 1

f 1 I Ua F (1-e **) /Z, (2) where U is the exploitation rate, F is the instantaneous fishing mortality, and " is the total mortality rate from all sources. The yield is calculated in metric tons by using average weight at each age--class from the data of Reintjes (1969) and is presented in Table 6--2. The number of fish which incur mortality from the power station is also calculated using formula 2 by substituting the

Lnstantaneous mortality rate due to the power station for F.

The effect of the power plant was simulated by first calculating a mortality rate due to power plant-related events (e.g. g entrainment, entrapment, and plume effects) The number of larvae e" entrained at Unit 1 during 1974 was calculated by integrating the densities observed in the entrainment studies throughout the year. An estimated 4.1 x 10 7 larvae were entrai.ned between June E and December of 1974. No larvae were collected during the R remaining portion of tha year. To extrapolate the effects of 2--unit operation, this estinate was then multiplied by the ratio g of the flow for Units 1 and 2 to the flow of unit 1 (3.75). 3 ) i To estimate the cortality rate which would result from this loss, the number of larvae produced by the simulated population was ( calculated. The age specific fecundity for menhaden was estimated from the p weight fecundity relationship of Higham and Nickolson (1964). [ The age specific mean weight from Reinjes {1969) was then used to obtain the age specific fecundity (Table 6-2). The equilibrium g population was multiplied times the fecundity to obtain an 3 f estimate of the nu=her of eggs produced. It was assumed that 1 in 10 eggs hatch. Th.is results in an estimated 1.45 x 10ta a larvae. The estimate of entrainment w ?.ality is: E i Me = -In (1-(1.53 x 10 8/1.4 5 x 10 2 3) ) = 1. 0 6 x 10 5 (3) The effect of inpingement of menhaden on the traveling screens was estimated from the screen-washing data collected in 1973. These data represent a complete year of collection and generally 3 agree with the other data collected in the screen washing g program. The screen-washing data does not distinguish between clupeid species; therefore, it is conservatively assumed for this analysis that all clupeids are menhaden. It is also assumed these fish are age-class I, since the.y are unidentifiable as menhaden. An average of 0.853 clupeids per hour were impinged during 1973. Assuming the power station runs continuously for a

year, 7,473 would be impinged.

The extrapolation to 2-unit operation assumes g fish are impinged in proportion to the rate of flow. This would g I J-j 6-te I e E

result in ?8,023 clupeids impinged each year. The estir.ated I additional wortality to the population would be: MI = -in (1 -2. 8 02x 10 +/2. 8159x 10 5) = 9.95x10 6 (4) E The effect of gas bubble disease-related mortality is g conservatively predicted by calculatir.g the additional mortality that would have resulted from a kill of the size which occurred at Pilgrim Unit 1 in April 1973 and imposing this additional 3 mortality each year. Since tht; mortality does not occur every year as evidenced by 1974 and 1975 data, this estir. ate is most likely an ove :-estimate. The 1973 fish kill has been estimated to be about 43,000 age-III fish. In

1975, a

smaller fish kill estirtated at about g 5,000 menhaden took place. The additional mortality to the g equilibrium-simulated population based on the higher 1973 kill would be: Mg = -In (1-4.3x 10 4 /3. 5x10 8 ) = 1.23x10-4 The mortalities attributed to the pwer station are added singularly and in combi. nation to the total mortality rate and the I population re-simulated. The number of fish which suffer mortality due to the power station and the percent of the equilibriet population affected were also calculated from the I simulation. The initial population structure and size for the simulation analysis was calculated based on the data frccn Schaaf and Huntsman (1972) for the year 1955. This estimate of population g size was calculated from the number of fish in the commercial catch and the 1955 age-specific exploitation rates (Table 6-2). The exploitation rate for age-c. lass I was two-thirds the average j exploitation rate for fish ages II to V. For fish VI years and g older the average exploitation rate was used. 6.8.2 Results of Thermal Plume, Entrainment, and Impingement it The ppulation simulation of menhaden with the parameters listed in Table 6-2 revealed a population which reached an equilibrium 3j size of 4.48x10' individuals and a stabic age distribution (Table 6-3). At equilibrium and an annual fishing mortaltiy rate of 36 percent, the yield to the ec==ercial fishery is 3.94x102 metric tens. The results of imposing additional mortality to the population to si=ulate the effect of entrainment, entrapment and the thermal discharge are presented in Table 6-4 The result of imposing an additional mortality due to entrainment is a population which comes to an equilibrium and is reduced in size by 0.00275 percent from the non-impacted population. 6-19

TABLE 6-3 SD:UIATED EQUILIBRIUM OF MDMADEN POPUIATION Population Age Yield Ace-Class Siz e (x 10 6) Distribution Rietric Tons), 1 2,815.9 0.629112 125,270 2 1, 14 4.8 0.255780 146,030 g 3 355.32 0.079386 75,096 4 110.28 0.024639 31,201 5 34.227 0.007647 11,122 3 6 10.623 0.002373 3,812 5 7 3.2970 0.000737 1,234 8 1.0233 0.000229 405 g 9 0.3176 0.000071 125 g 10 ,0_.0966 0.000022 39 Total 4,475.9 1.000000 394,334 t I I I i I I I I E I ,e, I

Tho simulation of cntrapment and the thermal effect reveal similar levels of reduction in population si:o of 0.00073 percent ated 0.00156 percent, respectively. These simulations also produced populations which reached an equilibrium. l Tho combined offects of all three sources of power plant mortality were simulated. The resulting population had a su ble equilibrium and a population size 0.00485 percent below the non-impacted populat. ion. 6.8.3 Cu==mlative Imcact The sirn11ation performed usi.ng the population dy.. nic model of Schaaf and Huntcman (1972) reveals a population which is rogulated only by the stock and recruitment function. The other e l popv*g. tion parameters which include age specific individual m ight, natural and finhing mortalities are co stants regardless of population density. Any perturbation t the population within several orders of magnitude of the-ast.imated for the Pilgrim liuclear Power

Station, Unitti 1 e,d a,

results in a change in the equilibrium population denuty, but not the stability of the equilibrium. It 10 difficult to predict the reductinn in the Massachusetts monhaden catch as a result of the opera *..on of Pilgrim Units 1 and 2, since Massachusetts does not represent a biolc>gical subunit of the tiorth Atlantic Menhaden population. An estimate in the redtetion in Massachusetts catch could be made for the tich which were killed by entrainment, entrapment and the effects of the thermal plume if these were assumed to all be traslated into reductions in the !bssachusetts catch. Those los.ses due to power station events may be compared to the yiold to commercial fisheries. The landings of 1..enhaden in all Macsachusetts ports ad the dollar value of the landings are prosented in Figure 6-14. A loss of 43,000 age-III fish which wac estimated for the 1973 fish kill would have represented or an approximate 0.11 percent of the 1973 Massachusetts catch dollar value of 1944. An estimate of the reduction in the commercial fishery catch as a rosult of power station operation (due to all 3 sources of t.rortality) was made for a constant rate of fishing mortality. Tha reduction in the tiorth Atlantic catch in the. impacted population vr. the non-affected population is about 104,073 fish per year. If it is further ascamed that the reduction in Atlantic menhsden population size of 0.00485 percent is represented by fish pound each, the Neight of this locs is then waighing about one 46 metric tons. This corresponds to about 0.5'T percent of the 19*13 Massachusetts catch, or a dollar value of about 2,285. 6-20 I

__*aL,u_ A-s m. A, 4 4..P-4 -__...4m_w_u.m--%-n-AheewAsh4m...-amwa.4 .A._Aw4-_u, Asau_sm_.., &Aa4.sh-4dLa 4*A h..,.*%-+,e4s c-aas. a ( 4 i I i, o a 1, 4 x = l t: c {2 8 8 a 8 f .L d a d 4 cl Y a e= e m o I e g C 5 E E 2-4 E R 3 2 Ah i W g, g m m m l I e t 3: ) g g 3

• p at :

C 5 EG p 2 1 9 2 C C C C C 3 a d d i a y leni:t l 1 l 4 ti n8 = s de e e + = 0 a 3 8 a fr. 1: e ca 5 su[w i t F[ y j zr se 'E~t l-l. - ) b"~r : i t. 3~ I t I 0 . =

J I 10,C 0 0 "50 seco 1 l 1000 3 .,00. . es l 0 5 me 5 l 0 is o;. " 55 o acoc-g g l 8} a 17 troo a 3 e 60 tcoD a 64 1500 + a66 g 59 62 g63 ui s 4000 - a65 308 too. 67 t 9 1 1 1 1 1 1 i t t f 9 o too soo ses too texc ince 1400 itoo isoo acco troo 340a 26co asco so:o M I LLIONS OF SPAWNERS i l i FIGURE O 14 THE RICKER STOCK AND RECRUITMENT FUNCTION FROM SCHAAF AND HUNTSMAN (1972) (OATA POINTS REPRESENT YE ARLY EsilvATES OF fish ABUNDANCE.)

l E iI 20

1. 660,547 '

~J $ 7!6,741 'y 0 e i. E E 5 y i. I mo it S ic e l E

1. 184,c70 Il 16,524 E

8 I12.970 (_ e i i 1970 tste alta ist) 1974 YEAR I I I I r FIGURE 6 15 MENHADEN LANDINGS FOR ALL MASSACHUSETTS PORTS (FROM U.S DEPARTMENT OF COMMERCE CURRENT FISHERIES STATISTICS, TOTAL L ANDINGS AND DOLL AR VALUE OF E ACH YEAR'S C ATCH) E

6.9 WItirER FI,0UNDER (PSEUDOPLEUFONICTESAMEAICANUS) The predicted effect of the operation of Pilgrim Units 1 and 2 on l the local winter flounder population during the 40 years the station is expected to operate is based on several conservative assumptions. The population which is affected is assumed to ba a [ closed population with no migration to or from neighboring B populations. This assumption is conservativo since additional mort ality is restricted to the local population without benefit of migration into or out of the area. The vinter flounder population is assumed to only reproduce in the Plymouth-Duxbury Harbor. Howe and Orntes (1975) reported that winter flounder north of Cape Cod showed limited move: rent from inshore grounds with 90 percent of the recaptures within the localized area where tagging was conducted. Since there are no [ estimates of the size of the breeding winter flounder population R for the Plymouth-Duxbury

area, the estimates of breeding population density made by Saila (1961) for Rhc>de Island were b

used. The density times the area of the estuary at mean low [ water gave an esticate of the breeding winter flounder population. The second assumption is that the winter flounder found in the immediate vicinity of the Pilgrin station are recruited into the local winter flounder population. This assumption is the basis [ for predicting entrainment impact c the local winter flounder B population. 6.9.1 The Model The winter flounder life cycle model used for this analysis was based on the model developed by

Hess, Sissenwine and Saila I

(1975). A Richer (1958) stock and recruitment function was parameterized by the method described by

Hess, et al (1975).

This function predicts the number of recruits of fish in age-I class I (R) from the total number of eggs produced the previous year (E): R (E) = E exp (-10. 0 9- (-0.15 4 x10-11 ) E) (1) This stock and reen11t=ent function is the only density-dependent co=ponent of the rodel. For egg densities in the population i below 6.15 x

1010, and increased number of eggs results in an increased number of yeulings.

For egg densities greater than 6.15 x 1010, an increase in eggs results in a reduced number of yer.rlings per egg. The life cycle of the winter flounder is assumed to have twelve age classes. The instantaneous natural mortality and fishing nortality rates for age-class II and older were assumed to be constant. Age-class I fish were assumed to have no nortality from tishing and a natural mortality rate of 1.928 (Table 6-5). 6-21 1 1

i i j The yield to the co= erical fisnery was calculated by assuming a constant age-specific weight frcm Hess et al (1975). Tne yield was calculated in metric tons using the fishing mortality and E l weights in Table 6--5. 5 The ef fect of the power plant was simulated by first calculating g the additienal moctality associated with the power plant. The g ef feet of entrainment was simulated using the mathematical codels for circulation and dispersion developed by the ataff of the g Ralph M. Parsons Iaboratory for Water Eesources and Hydrodynamics y at !GT. A description of the circulation

model, CAFE, can to found in Wang and Connor (1975),

and a description of the dispersion rodel DISPER, can be found in Leimkuhler (1974). The results of simulations of the center of mass for particulars in various locations are presented in Figure 6-164 for a southwest wind and Figure 6-16b for a northeast wind. An initial concentration of 2 x 10' larvae was loaded at uniform concentration throughout the Plymouth-Duxbury Harbor over the course of two tidal cycles. A sink was modeled at the node closest to the Pilgrim intake. Larvae were removed in proportion to the concentration ? the s ink. Flow was assumed to be l 2,500 cfs representing Units 1 and 2 operation. 5 The simulation vs run with and without the tower plant sink. 3 The percent reductxon in the nu-ber remaining in the harbor due 3 l to the sink cc= pared to the original cohort reaches a maximum of 0.01 percent after about 6 days. The difference in the larvae remaining in the harbor af ter 6 days with and without the sink compared to the number remaining in the harbor is about 0.1 percent. Since both numbers are small, the larger value of 0.1 percent is chosen as a conservative estimate of the additional nortality due to entrainment of larvae. A more detailed discussion of this work is contained in Pagenkopf et al. (1975). l An estimate ot mortality associated with impingement was made by ) extrapolation from Unit 1 screen-washing data. Extrapolation for 2 -unit operation, an estimated 769 flounder would be 1:: pinged per ] year. These are assumed to belong to age-class II. The estime.te of impingement mortality rate becomes: MI = -1n ( 1. -769/7 334 7) = 0. 0104 (3) 6.9.2 Results of Thermal Plume, Entrainment, and Impingement i The effect of the ^.hermal discharge can best be illustrated by J the data gathered in the field studies. Winter flounder a populations have been monstored preoperationally and g postoperationally in the vicirity of the thermal plume and at i } Warren Cove (control area). Figure 6-16 shows the densities of winter flounder at both stations. In most

cases, population 6-22 ss

~ ~ \\ L TABLE 6-5 PMJJ1TGS OF THE WIliTER FLOU!CG SIMU* ATIO!1 MODEL Initial In stant2.m. ot a Instantaneous Average Popuintien lintural Fiching Height I ^""-c ^*" Si=" ' rt"t$t" rt

• itv 3

r*'") Fac~"ndit' y 1 511,099 1.928 0.0 25.7 0

• 2 73,374 0.66 0.45 105.2 0

i 3 21,142 0.ff 0.45 272.3 260,000 4 8,077 0.6s 0.45 356.1 443,000 [' 5 2,662 0.66 0.45 489.2 637,000 3 6 876 0.66 0.45 607.3 813,000 7 283 0.66 0.45 707.9 970,000 8 95 0.6o 0.45 793.7 1,107,000 5 9 32 c.66 0.45 e61.4 1,217,0ca g 10 11 0.66 0.45 913.9 1,301,000 11 3 0.66 0.45 954.2 1,367,000 $2 j 0.66 0.45 988.3 1,424,000 1 617,636 ^ i g E~ g f l 4 1 of 1

l fI TABLE 6-5A }. RESULTS OF WTliTER TLOUNDER SIMULATION OVER A 40-YEAR PERIOD (Based on the Model of Hess et al,1975) Additional dortality population Site % Reduction Non-affecced l population 0 610,830 0 Entrainment 0.001 606,890 0.65 Impingement 0.0104 575,330 5.81 Entrainment and Impingement both 57t',950 S.87 8 I I i E I 4 I E I c I s l t I !t i I

4 5 5 i! I $x?, I l- <'., l a l (~~\\,/ ~'l ~ .i 1

• \\

K-! ss i p# / ~l / / -i / I .g N -1,, N "l li %= ( -1 ~~p / / .~ 1 -1 i l / =~"f .l l i i l ) 2 t. <'s' .i 2 2! l s -l yl s i

1. 5 j

i -t

sg s~

• )

23 / '~~ ~.,. 4 i .....am. j l I I l wu,w.u-. a m

~. a i i t I ,y / pd f 9 lI V l 3 12 4 %h* V i 1 FIGURE 6-16A. DEPTH-AVERAGED PARTICLE PATHS; l VELOCITIES TAKEli FROM " CAFE" USil1G TIDE Af1D 10-KNOT SOUTHWEST WIND g (FROM PAGEf1KOPF ET AL., 1975, FIG 8) I B

i N 1 l / I - /* y/ \\ / l H i I \\ '2 I i FIGURE 6-163. l DEPTH-AVERAGED PARTICLE PATHS; VELOCITIES TAKEti FROM " CAFE" USlflG TIDE Ai!D 20-Kt10T SOUTHEAST WillD (FROM PAGENKOPF ET AL,,1973, FIG,10 n-----~_--__-..__-__--_

i doncity was similar at both stations, both prooperationally and postoperationally. Reduction in the plume area population occurred in January, 1974, which coincided with station shutdown, but it probably was the result of sampling variability as it E j occurred briefly. In addition, the Warren Cove population was E i reduced in July and October of 1974 and, although the station was operating, there was no reduction in the vicinity of the pitrne. Thermal tolerances are given in Appendix A. For the most part, thermally related mortality occurs at tcraperatures higher than a those of the themal plume. Since the p1'.uro is buoyant and g flounder is a benthic species, only the imediate discharge. area will be affected. In su=:ler, larval nortality can occur in the in:me.diate discharg) area (one acre). Since this is an area of E activa station p1L:ne flow, only winter t'lounder larvae which have 5 passed through the station should occur in this area and thus sculd be entrained organisms. There organisms were assumed to be 3 killed by entrain.aent. E The simulated winter flounder population maintains its initial h population size and age distribt, tion (Table 6-16). The yield to 1 the con:nerical fishery for the simulated population would be 6.5 metric tons per year. The imposition of additional mortality due to entrainment of larvae produces a population which is reduced by 0.65 percent of ~ the original population la 40 years. The imposition of additional mortality associated with the impingement of winter flounder wa'; .:Imulated. The resulting population reached a level 5.8 percent below the unaffected population in 40 years. i The combined effecta of both inpingement and entrainment was also simulated. The population was depressed by 5.9 percent over the unaffected population in 40 years. The offeet of termination of power station operation was } investigated by using the impacted population as the initial population for an additional simulation without the effects of i the power station. Af ter 40 years of

recovery, the population had recovered 2.3 percent of the 5.9 percent it was reduced-in i

l 40 years of plant operation. 6.9.3 Cumulative Impact The simulation performed in this analysis for winter flounder g reveal a population which is regulated only by the stock and g I-recruitment function. The other parameters which include age-specific dadividual weight, natural and fishing mortalities are constants regardless of population density. I 6-23 I 1 l

The effect of the thermal pit =e on winter flounder is expected to be minisal based on Unit 1 opera + ag data. The effect of the entr ai;. ment of larvae and the inpingement of adults is predicted to reduce the population by S.9 percent in 40 years. The reduction in population size as a result of power station evants may be compred to the co=nercial fisheries catches. The average catch from 1970 to 1973 for both lemon sole and black back flounder, as reported by Passachusetts IAndings for all port a, was 6.850 metric tons per year. The predicted reduction ( in the wi.er population would result in a loss of 0.40 motric tonn from the cocmercial catch, assuming the population would be harvested at the same rate. 6.10 POI.10CK (POILACHIUS VIPD:S) m pollock is a predatory schooling fish species which is present at Pilgrin rtation during certain seasons of the year. Pollock could be subject to station impact through the thernal plune, entrainment of eggs and larvae, and impingement. The relative abundance of pollock in the vicinity of the station, as measured by gill net ecliections, is listed in Table 6-6 and ranthly variations are shown in Figure 6--17. The relative abundance of pollock increased during ste.cion operation and decreased then the station was down (Table 5--6). This cou,1d be due to two facters: (1) Natural mig 2.ations insnore in spring and fall with patchiness in collection techniques (this is common with gill net collections of schooling species). In other words, natural variability coincident with station operation. (2) It could be due to predation of pollock on migratory prey species drawn near the station. The decrease in sea herring and alewife densities in gill net collections occur when pollock density is greatest (Table 6-6). During station operation, there are more prey species and thus more predatory species in the area. 6.10.1 Thermal Plume There is little quantifiable evidence concerning the effect of the thermal plume on pollock. Visual observations indicate that pollock stay on the edge of the plume, feeding, and do not appear to be affected by the plume (R. Fairbanks, personal coc=unication). Thermal tolerance data (Appendi.x A) indicate that pollock mortality could occur within the 20 degree isotherm (less than 1 acre) during the su=ner months. Pollock avoid the im=ediate plume areas thus no mortality la expected. 6-24

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B I

6.10.2 Entrainment Pollock eggs and larvae are planktonic and therefore are subjecg to entrainment. tb eggs or larvae were co2.lected in a year om entrainment monitoring. As with lobster larvae, although none were entrained, scne pollock larvae have been collected in th3 vicinity of the station. These larvae are probably the result og minor offshore spawnings in Cape Cod Bay. Few pollock larvae were observed in ichthyoplankton collectionk in 1974 and even fewer in 1972. The average density-approximately a mile offshore was 0.28 larvae per 100 cubic meters in the 1974 spawning

season, and 0.003 larvae pee 100 cubic meters in 1972.

Baced on the combined projected intakW flow rate through Units 1 and 2, this could result in from 3.7 x 105 (1972 collections) to 3.6 x 106 (1974 collectioncg larvae entrained por year. The fecundity of pollock has becE l reported as high as 2 million eggs per year per female with an average of 225,000 eggs per female per year (Bigelow an Schroeder, 1953). Assuming 90 percent mortality from egg t larvae and using the model described in Section 6.1. this resul - in the equivalent of from 4 to 316 adults lost throu h entrainment of ichthyoplankton.

Again, this represents hypothetical worse case since no pollock eggs or larvae have be observed to be entrained b Unit 1.

6.10.3 Intrapmerit Some pollock have been entrapped on the intake screens at Unit A total of 12 pollock wero collected in 2,096 hours (1973) or i an entraptent rate of 0.005 pollock per hour. In 19* three po.u ock were impinged in 1,464 hrs (0.002 pollock/hr). Projecting the 1973 estimate for Units 1 and 2 yields an estimat$ of 0.019 pollock entrapped per hour. This entrapment ratM i recults in a total of 189 pc '. lock entrapped per yeaz.. 6.10.4 Ctraulative Impact tio station impact on pollock from heat or cold shot ; is expect 4 to occur through the thermal plume as behavioral observatior indicate that pollock position themselvea outside the plume. esti. mated number of adult pollock potentially removed from the population through entrainment and entrapment, varies from 1$ adults (no entrainment), 193 adults (based on 1972 offsho115 ichthyoplankton collections) to 505 adults (based on 1974 offshore colleetions). An assessment of the impact of this removal or the total pollocR popula, tion can be made based on cor:mercial harvest. Commerci fishing records only give harvest estinates based on evisceratt fish. The avernge annual harvest for Massachusetts (1970 -197 is 11.2 million pounds. Adult pollock potentially affected bv the station were assumed to be equivalent to a 5--pou. t } 6-25 5

I eviscerated fish. Therefore, the potential station-related loss would represent 1.0 x 10 *, or 2.2 x 10 4 percent, respectively, Il of the Massacimsetts commercial landings of

pollock, and therefore would be negligible.

6.11 CUWCt (TAUKGOLAmS ADSPF.RSUQ

Conner, is an abundant local fish species found in the vicinity of Pilgrim station.

The relative abundance of cunner was stable l frca year to year, both preoperationally and pstoperationally (Table 6-6) in the gill net catch. Although there was some population variabi.11ty f rom renth to conth (Figure 6-17) due to l variability in catch and movement offshore in winter. The 1974 W sport catch (Table 6-7) indicates the same trend as the gill net catch with cunner predominating in su=er and fall. Therefore, l cunner could e::pect to be most affected by utation op ' ration in [ sumer and f all. Ctmner could be af f ected by the thermal plunm entrainment of eggs and larvae, and entrapment. 6.11.1 Therral Plume Since the cunner population has been stable bc. prew trat :.a:u ny I anC postoperatio.. ally, it appears th*t Unit 1 has and little effect on the cunner population. 3ased on temperature tolerance data in Appendix A, the thermal plume F suld not result ih overt S g mortality of cunner beyond the discharge canal. During pericds 5 of maximum ambient temperature, (stmtner) cunner will probably not reside within the ten-degree isothem. Optimum spawning and 3 adult growth should take place outside this area during the g sunner months. In the fall, temeratures immediately outside the discharge canal vill be optimal for growth. In

spring, temperatures irnediately outside the discharge canal will be opt % 1 for spawning and for the incubation and hatching of eggs.

6.11.2 Entrainment Cunner eggs and larvae have been collected in entrainment sampics in 1974. Cunner eggs, however, cannot be diffs2rentiated from other labrid eggs; therefore, all labrid eggs were assumed to be cunner. Thi.s is reasonable, as most labrid larvae were cunner. The estimated density of labrid eggs encrained in Units 1 is: 3.46 x 106 0.016 eggs /ma x 120 days / year x 1.8 x 106.a3/ day = eggs / year. The estimated density of cunner larvae entrained is: 9.3 x 10-5 larvae /m3 x 120 days / year x 1.8 x 106 m3/ day = 2.01 x 10* larvae / year. To extrapolate the effccts of 2 unit operation, t.hese estimates were multiplied by 3.75. Assuming 0.1 survivorship of egg to larva, the equivalent of 1.64 x 107 eggs would be entrained per year. The fecundity of cunner has been estimated to be about 100,000 eggs per female per season (Willians et. al, 1973). Using the 6-26 i

i i I i 4 ) a I i i i i f TAJEE 6-7 t f STMT T15tsitG CA104 AT Pit / IsIM GTA7:Ota 1974 i j, April M June . *1g Aurust S*pt ele-r oct<#=-r povWr TUTALS f I st=<.us 2 e i 7 l ? At_lantJ c l Coat 17 24 1% 4 1 72 4 139 I Macaterel 2 2 5 i

• dinf er i

Flotander 60 7J 70 26 6 232 i l Follock 204 90 SS 25 8 4 10 eac l t Tautus 2 1 12 4 4 4 28 Cunner 9 175 2 ',0 157 466 244 1,294 l stz ipe-1 Bass 4 3 32 39 Diemiish a 66 6 15 69 7sc f -snapser-+ nluetish 1.436 140 1,176 ) 1 4 orean ~ t 6 6 i 1 American s.e1 4 4 m, 2 2 t 4

• yt e -of-t W r 3

7 i k I 1 i 4 ' hk IO w,

assumption of the population being in equilibrium (Section 6.1) this results in the equivalent loss of 274 adult cunners. l 6.11.3 Entrapment liinety-nine cunner were entrapped on intake screens at Unit 1 in 2,006 hours of monitoring or 0.047 cunner /nour from April through tbvemb2r 1973. Projected for Units 1 and 2, the entrapment rate would be approximately 0.22 cunner per hour or 1,036 c u n r. o r per l year. The average sport fish catch rate at Pilgrim Station is B also 0.2 fish per hour. This estimate is probably a conservative

e. stimate for cunner as cunner are casil, caught and therefore the numbers caught are considerabi.e.

The <stfects of entrap:.ent are therefore assumed to be negHgible. 6.11.4 Cumulative Impact Ib mortality is anticipated to re<,olt from t'ae thermal plume since lethal te neratures will not be reached outside the j discharge canal. Units 1 and 2 should result in cunner mortality B only through entrainment and entrapment. A conservative estimate of the total ntrr.ber of adults potentially recoved from the g population per year is 1,310 adults per year. Based on the high l relative ahindance of cunner in this area (Table 4-2 and Figure 6--17), the potential loss of 1,310 adults per year is erpected to have a negligible effect on this population. 6.12 RAn MOW S!GLT (OSinUS fj_ORDAX) The ect of the operation of Pilgrin Units 1 and 2 on the smelt i v populm., ion in the area is predicted from published life hisuory information and plant monitoring data. The sources of impact to g the population include entrainment of larvae and impingement of [ adults. The mtximtm te=perature predicted in the i. mediate area of the discharge is less than 940F during the summer. This temperature is near the upper maximum temperature tolerance i presented in Appendix A for smelt. It is therefore assumed that adult smelt win be excluded from the i m m e '. i a t e area of discharge. From the combination of the area of exclusion and the B mobility of the

adults, this source of impact is judged to be 5

nsgligible and win not be quantified in the present analysis. P.arine populations of this species generally spawn upstream of the tidal influence and the eggs are adhesive. While there is a net downstream revanent of larvae, McKenzie (1964). reports that larvae are carried back and forth under the influence of the tide. After a few days, the larvae become negatively phototactic which results in higher densities near the bottom during the day. It may be concluded from this strategy that larvae are retained in the brackish estuary and those which are washed out of the estuary have a lower probabibility of being recruited into the adult population. 6-27 1

Refer to Section 6.9 for a dincussion of the effect of tht. Piltjrim Station on populations in the Plyrouth-Duxbury Harbor. The analysis presented in Section 6.9 is for winter flounder; however, the ef f ect on the larval smelt population would be of a similar

nature, since both populations breed in the Plymouth-Duxbury area.

The smelt breed in the rivers vnile the flounder a j breed closer to the mouth of the estuary; therefore, the E predictions for winter flounder larvae entrainment will be over-esti=ates for smelt. 6.12.1 ThL Model Presently, there is no published population dynardes lif e cycle l r nodel for smelt. A paper by McKenzio (1964) was used to obtain statistics for the development of a life tabic for use in the present analysis. While the statistics were gathered for the smelt population of the Miranichi River in tiew Brunswick, f co:rparision with the work of Ruf el, Prost and Jones (1943) in Great

Bay, liew Hampshire, and Rothschild (1951) in Dean Breck, Maine, suggest the values are applicable to other populations.

l l It 12, therefore assu=ed that this life table is applicable to the population which could be af fected by Pilerim Station. i The life table for sralt is presented in Table G-8. The o l L survivorship for ages 2 th ough 5 and the estimates for fecundity were taken from Mcken:ie (1964). The survivorship for age 1 was assumed to be the same au for larvae to are 1 and the survivorship f o.: age 6 was assumed to be the sane as age S. The number of eggs produced by fish fram eges 2 to 5 was calculated using the McKen=de (1964) estimates of fecundity. A function for } egg survivorship was developed from 2:cKenzio. L = 89.91-0.00023 (E) wheret L is larval density per fte of surface area, and l E is egg density per ft2 of surface area. From this life

table, the mean length of a generation was

] calculated: } 32049.95 = T = J 1xMx 3.23 years, (1) 1xMx 9919.42 i where 3, x is age in years, E lx is the survivorship of age x, and Mx is the number of eggs produced by a g female of age x. g The esti. mate of fishi.ng nortality was taken from the Miramichi smelt fishery since no other estimate was available. This i 1 g 6-28 h

i L TAnns 6-8 LIFr TAh!1 FOR SF'ELT (1x) Fiching (Fb:) Age Survivorshim !br"ality Fecundity S exj,<a tio W lqht (qraar u;gs 0.024 0 0 ? Iarvae 0.043 0 0 1 0.044 0.04 0 8 2 0.452 0.04 11,348 0.77 14 3 0.136 0.04 19,705 0.77 17 4 0.098 0.04 31,327 0.75 22 1 5 0.027 0 42,532 0.76 32 6 0.027 54,153 0.50 I i I i i 1 k l 1 of 1

s I fishery uses trap nets. McKenrie (1964) entinated a 4 percent annual harvest for ages 2 through 4. Therefore, a fishing nortality of 0.04 per year was used in the simulation. An eatinate of the density of breeding cmolt in the Plymouth-m Dur. bur,/ Harbor in the late f all was made from data collected bye 3 the Massachusetts Department of Marine Fisheries in 1?*il. S:t.elt were collected in a 30-foot shrimp trawl in 5-rainute tows at 1 to 2 knots. The area swept by thic trawl was estimated to be approximately 1,411 mt. Smcit were most consistently collected during liovember when an average of 10.33 individuals (standard error of 2.84) were collected per trawl. It was assumed that this trawl had an eificiency of 50 perce.nt and, on the average, it sampled one half of the water column. It in also assumed that the adu.it smelt have a uniform distri.bution with depth. This yields an estimated density of breeding adults in the harbor of 0.0027 per ft2 cf surface area at nean low g water. The density of eggs in the Jones River, where the Massachusetts Department of Marine Fisheries collecte smelt

eggs, has been 3 estimated between 800 to 1,600 per square inch during each period 5 g

j of collection. It was assumed for conservatism, that the average density of eggs was about 1,000 eggs per square foot over the area which spawning takes place. The number of eggs produced each season (E) can be estimated: E = X.R.T, (2) where X is the standing crop of eggs per square foot, R is the area of the river which eggs are deposited, and i T is the turncver rate for eggs. The breeding adult population (A) which resides in the harbor during the f all is: (3) A = YeH, where: I Y is the standing crop of adults per square foot, and B is the area of the harbor. The turnover rata for adults is a ssumed to be one. The relationship between the mraber of eggs (E) and adults (A) in the population is: 6-29 E

l" E = A.F.S, (4 ) where: F is the fecundity, and S is the sex ratio. Substituting equation 3 into 4, and setting this equal to equation 1: F.Y.H.S = X.R.T. (5) Equation 5 can be solved for the turnover rate T: T= _H . F.Y.S (6) l R X 2 Esti: nates of the adult density Y and the egg density have been made. The average fecundity f rom Table G-8 is 14,770, the adult l density is 2 x 10-3, and the egg density is 103 per square foot., l The turnover rate becomes: I T= H .,1.5 x 10* x 2 x 10-3 7 = H 2.1 x lo-a n 10-a ~ R 103 R R The esthnate of the number of eggs in the population becomes: H. 10-2 (7) 10-2 =X E=X=R.T=X.R. H R The area of the harbor (H) has been estimated as 1.9 5 x 10 7 square meters at mean low water. Therefore, the number of eggs is catimated as: I 10-2 = 2 x 10' 1.95 x 107 10.764 E=X.H. 1c-a a 103 The initial population structure for the simulation is presented in Table 6-9. The estimate of the number of lazvae entrained results from an extrapolation from the dansities of smelt entrained at Unit 1. Based on these densities and the combined

flowr, of both

units, an estimated 8.51 x 107 larvae would be ent.5ained per year.

It is conservatively assumed that this loss would have been recruited to the adult population. The simulated population has 1.869 x loto larvae at equilibrium. The calculation of entrainment mortality is: Me = - in (1 - (8.51 x 107/1.8 69 x 101 o)) = 0.00456 (8) The number of melt impinged each year was estimated from the Unit 1 screen-washing data for 1973. The extrapolation for 2" unit operation assumes the fish are impinged in proportion to the 6-30

L i I: r i TABLE 6-9 INITIAL POPU MTIO!) STRUCTURE POR SIlitTIATIOli I;( Age purber Egg 2.09898 x 109 3l larvae 5.0376 x 107 5 1 2.166 x 106 2 9.5310 x 10* 3 u.3080 x 10* 4 5.8589 x 103 i S 5.7417 x 10m l,, 6 1.5503 x 101 I l, 3 I I I I I I 8 I< I I-1 of 1 5

flow. It is estirated that 5,313 smelt would be impinged per l year. It is assured that all these fish are of age 2. u The simulated population has 3.5361 :: 107 age 2 fish at equilibrium. The calculation of impingement mortality is: H = - in (1 - (4560/3.5361 x 107)) = 0.000129. (9) 6.12.2 Cu:nlative Impact The effect of this loss of young fish on the adult population was investigated by adding the mortality attributable to entrainment g and impingement to the simulated population. The effect of the g thermal plume was not considered in this analysis due to the negligible nature of the effect. I The populatiot. was resimulated, including the mortalities g associated with pcuer station operation. The population size and the yield to the fishery were depressed by 0.5 percent compared i to the non-impacted population. The it:pacted population came to Il equilibrium as did the non-i.mpacted population. The cirulation of the smelt population revealed a population l which reached an equilibrium size of 0.57 x 10e fish from age 1 to 6. The yield to the fishery, assu=ing an annual mortality of 0.04, was calculated as 1.94 x 106 fish, or 29 metric tons per yeer. 6.13 ATLANTIC SILVERSIDE (MENIDI4 !EurDIM The impact of operation of Pilgrim Units 1 and 2 on silversides is predicted from temperature tolerance

data, entrainment data n

and screen -washing data. Published life history data on H silverside was researched to obtain fecundity, sex

ratio, and length of life information.

6.13.1 Results of Thernal Plume, Entrainment, and Impingement Temperature tolerance information is presented in Appendix A, and the relationship between acclimation and tolerance te=peratures I. is presented in Section 5.12. Based on those data, si.1versides can be anticipated to be excluded from about 11 acres in the immediate discharge area. It is expected that many of the fish vill simply move to other areas to avoid the thermal

plume, due to their motile behavior.

The ef feet of this impact will not be quantified in the present analysis. Larval silversides were collected on three dates in the entrainment studies during 1973. Integrating the density of larvae collected provides an estimate of 2.809 x 106 larvae entrained for 2-unit operation. The equivalent number of adults was estimated by assuming the fecundity is 300 eggs per female, and that 1 in 10 eggs hatch (Baylif f, 1950). 6-31 l l + 1_ _ _ _n ____ _

187,267 adults per year 2.809 x 106 x (2/300 x 0.1) = N a Assuming an adu1*. silverside weighs about 10 grams, (Austin, e t I al., 1973), the loss of this many adults would be equivalent to a 1 loss of 4,125 pouads per year. The loss due to impingement has been estirated from data collected in the screen -washing program for Unit 1 in 1973. The predicted loss for both Units 1 and 2 is 9,070 fish per year. Assuming again these fish weigh 10 grams each, this results in a loss of 178 pounds per year. l The combined ef fect of entrairr' and inpingement is predicted EI to be 195,337 fish per year, or ut 4,303 pounds per year. Since this species is not of ec=:: ial value in Massachusetts, no cccparisons with co:=aercial catch _ < n be und e. Anderson

and, Power (1950) reported that in 1946 in New York State 126,300 pounds of silversides were ce=nercially caught.

The availability of silversides may also be indexed by the number l b caught in seines. Bigelow and Schroeder (1953) reported that up to 3,500 were caught in a single seine haul from the southern side of We Gulf of St. Lawrence. Warfel and Merriman (1944) reperted as many as 1,938 in a 30-foot seine which was fished for i about 100 feet parallel to shore in water less than 4 feet deep. 1 6.13.2 Cumulative Impact i The offoct of the thermal plume is expected to be minimal to silversides based on the abundant nature of the species and the area from which they could potentially be elir.inated (11 acres). An estimated 187,929 and 8,070 adults could be lost from entrainment and impingement, respectively. These losses assume no compensatory mechanism in the populaticn and are theref cro an over-estinate of the impact to this species. Although there are no direct estimates of the population sire in the

area, the abundant nature of this species would suggest a minimal impact to l

1 the population frcn this additional source of mortality. 6.14 AIZWIFE (ALOSA PSEUDOHARDiG'US) The impact of the operation of Pilgrin Nuclear Power Station, Units 1 and 2, is predicted from published life history inforration and station operation data. The sources of possible j impact from station operation include the thermal

plume, entrainment of larvae, and mortality of adults on the traveling screens.

6.14.1 Results of Thermal Plume, Entrainment and Impinge =ent Based on the studies of de Sylva (1969) presented in Appendix A, and the predicted areas of various isotherms in Section 2, it is predicted that alewives will be excluded from about 3 acres in the ir::nediate area of the discharge. The studies of Huntsman 1 1 g 6 12 i i 08. I 5

(1946) indicate alewives are able to tolerate a temperature of 68.60P, which is near the predicted su:ener maximum surface L temperature at the discharga area. From the above-nentione d in f ormation and the mobile nature of fish, it is anticipated that most alewives will avoid the thermal plume. Since thic should not constitute a probica, it wi13 not be quantitatively considered in the present analysis. Calcula t. ion of entrainment impact was made by assuming the average fecundity is 229,000, the sex ratio is 1 to 1 (Kissil, 1974), alewives reproduce 3 times in their life (!'.arcy, 1969), I and the survival of eggs is no less than 1 in 10 (Edsall, 1970). For further details on life history information, see Section 5.13. The number of larvae predictod to be entrained with 2 units operating at the Pilgrim site was predicted from Unit 1 entrainment studies conducted in 1973. Integrating the densities I collected over the entire year and extrapolating for 2 units, 4.7643 x 107 larvae would ha antrained annually. I I:xtrapolation of larvae lost through entrainment to adults lost is made with the method outlined in Section 6.1. The estimated l number of adults which could have resulted from entrainment losses ic: 21 =ti.S = 4.7643 x 107. 2/ (3 x 229,000 x 0.1) = 1387 adults / year i The losses due to impingement are predicted from data collected in the Unit 1 screen-washing program in 1973. Since the fish l collected in this program are crall, they are only identified as 5 clupeids. u with other clupeids considered in this

report, it i

is conservatively assumed

that, all clupeids impinged are alewives.

The predicted number impinged each year is 28,023. The corbined effects of impingement and entrainment should be less than 29,410 fish per year for 2--unit operation. This l analysis assumes no compensatory mechanisms in the population which would be reduced by this number. The analysis also does not consider other species than alewives collected in the clupeid category in the screen-washing program. To give some perspective to this number of fish, Kissil (1974) reported 184,151 and 140,203 (average, 162,177) alewives in Bride

Lake, Connecticut, which has an area of 18.2 hectares.

If the same breeding density were to occur in the areas near the Pilgrim

station, this vould be equivalent to removing spawning adults from 3,67 hectares, or 9.06 acres.

The weight of adult alewives can De roughly calculated at about one--half pound. Eigelow and Schroeder (1953) reported that in 6-33

i Cape Cod Bay and the Merrimack River in 1896, 526,500 fish were caught, which had a total weight of 293,671 1:ounds. This is

a. bout 0.56 pound per fish.

Using this average weight, the 29,410 fish would weigh 16,470 pounds. This would have been 6 percent of this catch. Unfortunately, no recent catch statistics for the local alewife fishery are known to exist. 6.14.2 Cumulative Impact The effect of the thermal plume is expected to be of a ninimal E' nature to the population. With no compen sation in the 4 population, 1387 and 28,023 adults could be lost from the population annun11y due to entrainment and impingement, 3 respectively. The effect of this additional nortality is 5 expected to be c

• a mini:nal nar.ure to the population.

I I I I I I I I li I I I 6-34 5

6.15 REFERENCES - SECTION 6 9 References for 6.1

Leslie, P.H.,

1945 "On the Use of Matrices in Certain Population E Mathematics," Biometrika, 33:183-2V2.

Reinsch, J.W.,

and Wilkinson, J. 1971 " Handbook for Automatic Co:rputations, a Volume I: Linear

Algebra, Springer Verlag.,

Berlin. References for 6.4 mNp

Sameoto, D.D.,

1969. Physiological Tolerances and Behavior j'V t Responses of Five Species of Haustoridae (Amphipoda: Crustacea) to Five Environmntal Factors. Jour. Fish Res. Bd. Can. 26 (9) : 2283-?298. I References for 6.5 Beals et al, 1970-1974. Massachusett.s Coastal Lobster Fishery Statistics. Division of Marine Fisheries, Massachusetts Dopartment of Natural Resources. f

Saila, S.B.,

Flowers, J.M., and Boghes, J.T., 1969. Fecundity of American Lobster,,Homarus americanus. Trans. Am. Fish. Soc. No. 3: 537-539. References for 6.6 Purchon, R.D., 1968. The Biology of the Mollusca, Pergamon Press, Iondon, 560 pp. References for 6.7, t

Newell, R.C.,

Pye, V.I., and Ahsaaullah, M., 1971. The Effect of '1hermal Accli. stian en the Bcat Tolerance of

• he I.ntertidal Prosobranchs Littor m littorea (L) and rionodonta lineat_a l

(DaCosta) J. Exp. Biol. 54:525-533.

Purchon, R.D.,

1968. The Biology of the Mollusca. Perr.zon Press. Iondon, 560 pp. E.efarerces for 6.8,

Clay, 3.,

Barker, A., Testaverde, S., Marcello, R.,

nd McLeod, G.C., 1974. Observauions'cn the effects of gas ( -olism in captured acult mtnhaden. Proceeding, U.S. Atomic Energy Co: ' 'sion and Battelle Northwest Laberatories Gas Bubble D_sease WceksLip, October 8-9, 1974. Richland, Washington. 6-35 b

i ) I l

DeMont, D.J. and Miller, R.W.,

1971. First reported incident of gas bubble disease in the heated effluent of a steam generating g station. Proc. 25th Imn. Conf. S.E. Assoc. Game and Fish Comm. g l

Higham, J.R.

and Mickolson, W.R., 1964 Sexual Maturation and Spawning of Atlantic Menhaden. Fish. Bull, 63 (2) : 255-271. Marcel.lo, R.A. e.C Fairbanks, R.B., 1974. Gas bubble' disease mor* 5'ity of Atlantic menhaden, Brevoortia tyrannus, et a coastal g nuclear power plant. Presented.it: Battelle !iorthwest and U.S. g l Atomic Energy Co:=iscion Gas Bubble Disease Workshop.

Richland, Washington.

Reintjes, J.W.,

19 9. Synopsis of biological data on the Atlantic menhaden, brevoortia tyrannus. U.S. Fish Wildl. Serv., Cir. 320, 30 pp.

Ricker, W.E.,

1958. Handbook of calculation for biological statistics of fish populations. Fish. Res. Bd. Can. Bull. 19, 3 ,i ; 300 pp. 3 I Schaaf, W.E. and Huntsman, G.R., 1972. Effects of Fishing on the Atlantic Menhaden Stock: 1955-19 0. Trans. Amer. Fish. Soc. l 101:290--297, i References for 6.9 l

Hess, R.W., Siss enwine, M.P., and Saila, S.E., 1975.

Simulating t the Impact of the Entrainment of Winter Floc.nder Larvae, p. 1-29. 3 In:

Salla, S.B.,

Fisheries and Energy Production, a Symposium. 5 Beath & Co., Lexirgton, 300 pp.

Ecve, A.B.

and

Coater, P.G.,

1975. Winter Flounder Movements, Growth and Mortality of f Massat husetts. Trans..:Lm e r. Fish Soc. ) 104(1): 13-29. 4 Leimkuhler, W.F., 1974. A two -dimensional finite element disperr' n model. Thesis, Dept. of Civil Engineering, MIT. Pagenkopf, J.R., Christodoulon, '., and Pearce, B.R. 1975. A j Progress RepoI.t for Circulation Er. Dispersion Studies at the Pilgrha 11uclear Power

Station, Rocky

Point, Mass.

Ralph M. Parsons Lab., M.I.T., 40 pp. i

Saila, S.B.,

.361. The Contribution of Estuaries to the Offshore hinter Flounder Fisheries in Rhode Island. Gulf and aribbean Fisheries, Inst. Proceedings 14th Annual Session,1;over.ber 1961. t

p. 95-109.

Wang, J.D. and Connor, J.J.,

1975. Fathematical Modeling of Near i Co astal Circulation. Report 16. 200, Ralph M. Parsons Laboratory, Dept. af Civil Engineering, MIT. 1 I l 6-36 a

I References for 6.10

Bigelow, H.B.

and Schroeder, N.C., 1953. Fishes of the Gulf of Maine. U.S. Fish and Wildlife Fervice, Fish Bull. 53 (74) :577 pp. References for 6.11

Serchuk, F.M.,

1972. The Ecology of the Cunner, Tautocolabrus adspersus (Walbaum) (Pisces: Labrida e), in the Weweantic River I

Estuary, Wareham, Massachusetts.

M.S. Thesis University of Massachusetts, Amherst, 100 pp.

Williams, G.C.,

Willians, D.C.,

and

Miller, A.J.,

1973. Mortality Rates of Planktonic Eggs of the

Cunner, Tautocolabrug adspersus (Walbain),

in Long Island Sound. In Proceedings of a .I Workshop on Egg, larval and Juvenile Stages of Fish in Atlantic Coast Estuaries. Nat. Mar. Fish. Serv., Middle Atlantic Coastal Fisheries Center, Tech. Pub. 1. References for 6.12 l McKe'azie, R.A., 1964. Nelt Life History and Fishery in the Mirtsichi River, New Erunswick. Fish Res.

Board, Canada.

Bull No. 144: 77 pp. .I Rothschild, B.J., 1961. Production and Survival of Eggs of the American Smelt osmerus mordax (Mitchill) in Maine. Trans. Amer. Fish Soc. 90: 4248.

Warfel, H.S.,

Frost, T.P.,

and

Frost, W.H.,

1943. Ce Smelt Osmerus mordax in Great Bay, New Hangshire. Trans. Amer. Fish Soc. 72 : 257-262. I References for 6.13 Andersen A.W. and Power, E.A. 1950. Fishery Statistics of the United States, 1946. U.S. Fish Wildl.

Service, Statistical Digest 19, p. 118.

Austin, H.M., Dickinson, J.,

and Hickey, C. 1973. An Ecological Study of the Icthyofauna at the Northport Power

Station, Long Island, New York.

Long Island Lighting Company, 248 pp. Eayliff, W.B., 1950. The Life History of the Silversids Menidia menidia, Chesapeake Biological Laboratory. Publ. No. 90, 27 pp.

Bigelca, B.B.

and Schroeder, W.C., 1953. Fishes of the Gulf of Maine. Fisher.,y Bulletin 74, Vol. 53, 557 pp.

Warfel, F.E.

and Merri. man, D., 1944. Studies on the Marine Resources of Southern New England. I. In analysis of the fish population of the shore zone. Bull. of Bingh. Oceanographic I Coll. Vol. 9, pp. 2-91. 6-37 I I

Peferences for 6.14

Belding, D.L.,

1921. A Report Upon the Alewife Fisheries of g Massachusetts. Division of V.arine Fisheries and G6:ne, Dept. of g Conservation, Boston, Mass., 135 pp. de

Sylva, D.,

1969. Theoretical Consideration of the Effects of Eeated Effluents on Marine Fishes. In: Krenkel, P.A. and F.L.

Parker, ed. Biological Aspects of Thermal Pollution.

Vanderbilt Univ. Press, pp. 229-293.

Edsall, T.A.,

1970. The Effect of Temperature on the Rate of Development and Survival of Alewife Eggs and Larvae. Trans. Amer. Fisb Soc., 99(2):376-384.

Huntsman, A.G.,

1946. Heat Stroke in Canadian Maritir.e Stream Fishes. J. Fish. Res. Bed., Canada 6 (7), 7 pp. B 5

Kissil, G J!..

1974. Spawning of the Anadromous Alewife, Alosa eseudoharencus in Bride Lake, Connecticut. Trans. Amer. Fish. 3 Soc. '03(2):312-317. 5

Marcy, B.C.,

1969. Age Determinations from Scales of Alosa oseudobareneus (Wilson) and Alosa aestivalis (Mitchill) in Connecticut Waters. Trans. A=er. Fish Soc. 98(4):622-630. I I I I I I I I l 6-38 I. E

E SECTION 7

SUMMARY

OF ENVIRO!CCNTAL I!OACTS AND CONCLUSIONS 7.1 I2C/,ODUCTION The impact to the marine environment as a result of the operation I of Pilgrim

Station, Units 1

and 2, has been predicted by investigating 13 representative important species. These selected species are distributed at all trophic levels from primary producers to highest level carn vore. Species in all I habitats which might be affected by station operation were considered. Species selection was based on dominance, co :mercial importance, sensitivity and potential of incurring impact. The 1 pact to the fish populations in the area is analyzed by a population simulation where sufficient population dynanics data is available for parameterization. The effect of station operation is predicted by comparing simulation results with and without the effects of power station operation. For those species on which no population simulation was performed, the I nu:cher of adults which could have resulted from station-related loss was predicted. This pretliction was compared to some index - of population si::e. I The predictions of impact represent very conservative predictions j because the following criteria were generally used: (1) Maximum station flow rates and temperatures are used to i estimate numbers of organisms af fected. (2) The nearfield density of planktonic stages of representative species is used to predict potential entrainment of organisms i at Units 1 and 2 even though they may not have been observed in the entrainment collections at Unit 1. (.> ) One hundred percent mortality is assumed in calculations of most mortalities of entrained organisms, even though it is I li.kely that mortality estimates vould be lower under norr 1 operating conditions during certain times of the year. i (4) Conservative estimates of bio 1N cal paramc ::ers sucu as fecundity and survivorship of particular species are made when literature values are not available. ,I (5) In many

cases, estimates of i= pact did not include i

compensation (density dependence) within populations. - 7.2 SUtmARY OF I:CIVIDUAL SPECII.S IMPACT g The primary impac t of Units 1 and 2 will have a minimal ef fect on g Irish moss in toe i.:nediate vicinity of the thermal plume. The h g 7-1 gM O Me d G aM N 44 g ,ygy g ag., eg-6 t'.Oaa g gg g O

4 1 l i i .ty of Irish ross may be reduced within 2.1 acres in the area os .ie the:r-al plume. However, growth outside of this area is expected to increase as a result of the slightly elevated water temperature. Entrainment of spores ray occur, but mortality on 3 passage through the station is expected to be low. No station-g related impact is expected to occur due to entrapment. No sta tion-related d=pa ct is expected to occur to roc}Need as a result of entrainrent or entrapment. sore nortality ray

occur, attributable to the the=al

plume, but it is expected to be negligible.

No station-related i= pact is expected to occur to A. millsi as a result of entradrment or entrapment. Negligible irpact is 3 expected from the thermal plume as A. In111si will not be exposed 3 l to lethal te=peratures. The impact of the thermal plume on lobster should be minimal since lobsters are relatively robile and can avoid areas of high temperature. F.ntrapment of lobster should not occur because incake velocities are low. Entrainment of lobster larvae could 3 occur although it was not observed at Unit 1. Conservativt W i estimates of adult lobster potentially lost through larval entrainment represents less than 0.6 percent of the annual lobster harvest of Plymouth County. No station-related effect is expected to occur to the mussel as a result of entrapment. The potantial impact of Units 1 and 2 on the common muss el will rcsult fron the thermal plume and entrainment. Some mortality will occur within 2.1 acres of the discharge area during the su ser months. Utilirint conservative 3 estimates of rortality and number of larvae potentially 3 entrained, it was predicted that the nunher of adults lost would approximate the density of inussels from an area of 24 acres. B

However, considering that mussel densities both pre and g

j postoperationally at Unit 1 are sir <ilar, this iMicates that an overestimate of pote9.ial effects was made. Because of the extremely large nunbere of mussels in the area of Cape Cod

Bay, it is believed that any effect potentially attributable to the l

l operation of Units 1 and 2 would be negligible. The potential impact of Units 1 and 2 on the periwinkle will be similar to that of the =ussel. Some mortality will occur within l 2.1 acres of the discharge area during ths str=ner months. m Additional entrairruent of larvae could result in the loss of L. g littorea frcm an area as large as 23 acres. However, as with the i mussel, effects attributable to Unit 1 were not obtained post-operationally, and t*2 large abundance and distributions in Cape Cod %y would inc.tc ate that potential effects muld be l negligible. The effect of the thermal plume on Atlantic menhaden has been l observed to result in mortality due to gas-bubble disease. This l g 7-2 I I ~ g

E source of nortality, plus those anscciated with entrai:unent and entrapnent, were predicted by a pcpulation si.mulation. The result of all 3 sources of nortality is a reduction of 0.00485 percent below the non-impacted population. Since the I offact of the station on the North Atlantic menhaden population is expected to be ne g ligib'.e, the population should not be adversely affected. The effect of the thermal plume on winter flounder is expected to be minor due to the benthic nature of the species. The offect of I entrainment and ir:pingement were investigated by a simulation of the local population. The conservative prediction is a 5.9 percent reduction in the local winter flounder population in 40 years of staticn operation, assuming very little compensation I within the population. If the population is allowed to recover for 40 years after station operation, it recovers within 4 2.3 percent of its original population size. Fluctuations in the size of the population predicted as a result of station operation should not adversely affect the balanced indigenous flounder population. = Pollock may experience some m7rtality within the 200 isotherm (less than or.e are). Pollock have been observed f eeding at the h edge of tha thit 1 plume. Pollock may suffer some loss due to 3 entrainment and entrapment with a predicted 189 to 505 fish loss from the population due to these events. This potent:Lal loss is g about 2.2 x 10-4 percent of the lussachusetts landings for this I species. Mortalities of such magnitude as a result of station operation would not adversely affect the balanced indigenous pollock population. Cunner feed on small fish and c: ustaceans. They move offshore in I winter and spring and move close to the station in summer and fall. Since cunner can avoid lethal temperatures, no ef fect is I expected due to temperature. Cunner eggs and larvae are entrainable and conservative estimates yield a loss of 274 adults per year due to entrainment. Cunner are also

impinged, so impingement can account for the loss of 1,036 cunner per year.

Thus, 1,310 adults a year could be potentially lost. Considering the ubiquitous nature of this species in Cape Cod Bay, losses of this magnitude should not adversely affect the balanced I indigenous population. The effects of the thermal plume may result in the exc'usion of I smelt from the area i:r nediately adjacent to the discharge during sur:aer periods. The ef f ects of entrainment and i:apingement were simulated on the locally spawning smelt population. the I population level is predicted to be depressed 0.5 percent over the nm..tmpacted population. This effect is expected to be of a neglip ble nature to the population and therefore should not adwrnely af fect the balanced indigenous smelt population. I 7-3 I

I Silversides are expected to be excluded from 11 acras in the area E of the discharge during su.= er. Entrainment is conservrtively W predicted to result in the loss of 187,267 fish from the population while impingement could result in the loss of 8,070 fish. The ec=bined losses are believed to constitute a small fraction of the population, probably less than the year-to-year variation in population size. The effects of the thermal plu=e on the alewife is expected to be the exclusion of adults from 3 acres in the imediate area of the discharge during su.=er months. The effects of entrainment and 3 impingement are conservatively predicted to result in the loss of 5 29,410 adults fran the population. Based on the aburdance and life history strategy of this species, this loss is expected to a have a minor effect on the population. g 7.3 Col;CLUSIO!is The effect of the opfration of Pilgrim Station on the marine ecosystem has been addressed through pred.icted impacts to selected species populations and the general characteristics of 3 the ecosystem. The effects on pcpulations which were studied 5 y appear to represent a small fraction of the species population. It is believed that these ineses would be less than the observed year-to-year variation in total standing crop. a The general nature of the marine ecosysten in the Cape Cod Bay area can be inferred fran the studies at the site. The trophic structure is chararterized by divcrsity at all levels wi many I interactions between species. There also appears to be a high degree of redundancy in functional groups. Characteristics li.ke 3 the ones mentioned suggest the ecosystem should be able to 3 withstand impacts such as those predicted frce Pilgrim station with a minimal change in structure and fuiction. It would also suggest that the risk of irreversible dama72 to the ecosystem should be mir.inal. This assessment of environmental impact, based on an analysis of impact on 13 representative species indicates that Pilgrim l Station Units 1 and 2 with the proposed cooling system will not adversely affect the " balanced indigenous population of

fish, shellfish and wildlife."

3 l R

S J.D.No. 12577 F L a AFPENDIX A I HYDROTHERMAL DATA PILGRIM NUCLEAR PO'nT.R STATION - UNITS 1 AND 2 BOSTON EDISON COMPANY I ii l I l'

TIXPERATURE DATA SHEET Species: CHOC RUS CRISPUS - IRISH MOSS E ps I. Mortality 14 thal Accli=ation Data Te perature (F) Life Stace Ercosure Tine Te peracule, Source 95 Canospore 6 r.in 700F Prince (1971) 0 80 Tetraspore 53 F 81.5 100% 4-10 days II. Growth Opti=u: Data Te oerature(F) Rance Life Stace Source 68 28-68 Mathiesen & Prin ce (1973) Data III. Reproduction: Optiren Rance Month (s) Source Migration Spawning Incubation / 70 40-70 Prince (193, Hatch I I I I E ~ I A-1 I 5

~. a.. .... ~.i-=- ^ .~ T.= ~' ~ I A i T M ERATURE DATA SHEET Speciest. ASCOP.-iYLnM NO30 guy. - ROC K ED I'. Mortality L Lethal Acclict. tion Data _Te=p e ra t urs (F l life Stage Enosure Time Teteerature Source g Fritsch (1945j S7 Thallus 4 3 i I 4 E t i E 3*, I t

I 4

L f drg .-2 , I 4 ---4 -- 4

I .l c R-i TD'JERATURE DATA SHEET -5 Species: ACANTHOFAUSTORIUS MILLSI - AMPHIPOD ) I. Mortality Lethal Acclimation Data 1ceperature(F) Life State En ost.. Time Temperature Source 97 48 hr 77 _S ame ot o (19 )k I i. I i I i, I I I I I I f I-I t - < l ' I f1 I' A-3 i 1.* 3

E TEK?ERATL*RE DATA SHEET Spe:ies: ECMARUS AMERIC.W S - AMERICAN LOESTER I.- Mortali?.y I Lethal Accli=ation Data Terpe rature (F) life Stace Exposure Tien Teneerature Source 77 adult 4 t. Meleese (1956) 83 adult 59 McLeese (1956) 87 edult 1) hcLeese (1956) 84.5 larvae -24 hrs. Battelle Me orial Inst. (1974) T II. Growth Opticus Data Teteerature R. ace Life State Scurce 68-71 larvae Shastv eers. ce=. 65 adult Shasty pers. ecen. 28-74 iuvenile S_ hasty vers, c o=. l 71-75 Huches et.al.(1972) Data III. Reproduction: Opticu: Rance Month (s) Source . r.cubetion/ Hatch 54-59 Jun+-Autug Sherman & Levis T (1967) [ 68 j9-69 Euphes & W Mathiesen(1962) Acclimation Data I. IV. Preferred Life State Tercerature Source 28-75 McLeesc & Wilder (1964) I g ^~' I-

1 TEMPERATUP2 DATA SEEET 1' Species: MYTILUS EDULIS - 3LUE MUSSEL I. Mortality Lethal Acclimation Data ) Tenperature( Q Life Stage Ercosure Time Tenperature Source 80-105 _ Kennedy & g Minusky (1971) g 105.4 adult 59 Henderson (1929) S6 larvae 16-17 days Brenko & Calabrese (1969, II. Crowth l Optinus Data Teneerature Rance Life Stace Source I 41-68 Allen (1955) t Data III. Reproduction: O_otinug Rance Mor.th'(s ) Source Migration 80 Hutchinson(3947 Spawning 67 Engle & Leosr.noff(1944 h 5 j Incubation / Hatch 54.5-Engle & 4 71.6 Loosanoff(19 Settling 54.5-June-July Engle & l 66.2 Loosanoff(1944) I I i ~ I I I i I I A-5

I TF.XPERATURE DATA SHEET .l-W Species: LITTORINA LIT 70REA - COjo!ON PERIWINKLE I. Mortality Lethal Acclination Data Teeperature(F) Life Stace Ex:osure Time Temperature Source 87 TLs adult 24 hr 52 Neva11 et al(1970) 84 tlc 96 hr 52 Newell et al(1970) 90 TLs 24 hr 61 Newell et al(19,7g 87 TLs 96 hr 61 Newell et a1(1970) f 104 TLs Frtenkel (1960) - I I 'I I. l I I I 1 1

B g.

I 'B I ^~' I

TDGERATURE DATA SHIET Species _BREVOORTIA TYRPJJCS - ME!GADE!I I. Mortality i. Lethal Acciteation Data Te=reraturar(F) Life Stage E>mosure Time 'Jeet e r at ur t Source 85 CTM adult 24 hr _, _,_ 6 9 Eettler(1971) 38.2 larvae 44.6 Kinnt(1970) 39.4 larvae 50 Kinne(1970) 40.0 larvae 54.5 Kinne (1970) _ 41.4 larvae _ 59.0 Kinne(1970) 84.0 larvat. 50.0 Enne(1970) l 93.2-95.0 $uvenile 80.6 clark (1969) 1 84 iarvae 50 Moss et al(197W 5 ~1 85 j uver.ile 59 Hoss et al(1973) l j 93.2 juvenile 132 hr 69.8 , Lewis & Hetti 95 iuvenile 75.2 '.ewis & Mettler 96 iuvenile 84.2 Lewis & Eetti 95 j uvenile 84.2 Lewis & Kettle 5 f 32 larvae 44.6 Lewis & Mettler. 91.8 Gift (1971) k a i 86 adult 24 hr EpSr_clie d g 0 Acclimtion Data IV. Preferred Life Stage, Temperature Scurg 51-69 adult Brigs (19 Q), 70 adult 79 Maidriu & 61f319.i.U t I 1' A-7 5'

TEM 7ERATURE DATA SREET Spacies: PSEUD 0FLEUR0NOCTES AMEKICANUS - VINTER FLOUNDER I. Mortality } Lethal Accli=ation Data Temperature (F) Life State Exoosure Tire Tercerature Source 90.3 adult 77 Hoff ; Vestcan(1966) I 84.7 adult 82 Hoff & Westman(1966) 89.4 adult 72 Hoff & Vestman(1966) 89.6 adult 44.8 Hoff & Vest =an(1566) 33 adult 44.8 Hoff &

I Westman(1966) 34 aduit 70.2 Iloff &

Westnan(1966) 41 adult 82.0 Hoff & Westman(1966) 84 larvae 50-59 Hoff & Westman(1966) Upper .l Threshold 68-71.6 larvae 5-13 nin 44.6 Coutant(1974) N 71-74.7 5-13 min 57.2 coutant(1974) 7 7-r30. 6 5-13 min 69.8 Ceutant(1974) 85 adult 82.4 Huntsman & I ~ ~ Soarks(1966) 87-91 adult 69 Gift & West =an(1971 I II. Growth I Optimum Data

• e=cerature (F)_ Ranro Life Stage Source 52-60 adult Frame (1973)

Data III. Reproduction: Optimum Ranze Month (s) dourcai Migration 28-70 Sigelov & Schroed er(19 53) Spawning 'i8-43.7 32-44 Jan-Mav Conn Fishes _ Incubation / Match 38 32-53.6 15-18 days Conn Fishes Accli=atien Data IV. Preferred Life Scare Temocrature Source 51-80 adult Briers (lo73l 67 adult 57 Meldrin & l 8. Cift(1971) A-8

4 TDOERATEE DATA SHIET Species: POLIACE!1?S VIRENS - POLLOCK I. Fbrtality Lethal Acclir.ation Data Te=perature(Tl Life Stace Enosure Time Te=nerature Source 82.4 desviva(1969) l Data V III. Reproduction: Op ti=c=, Rance Month (s) , Source Migration 1 Spawning 38 36-44 Bigelow & g Jchroeder(1955 Incubation / Hates 43-49 Dec-March Bigelov & Schroeder(ly 'i Accli=ation Data IV. Preferred Life State Te=perature Source 51-56 adult Brites (1973) i 1 I I l I I i t 1 I 4 4 A-9 I .j ma g

TEMPE?Al'URI DAIA SHEET . Species: TAUTOGOLABRUS AD5?EFSTJS - CUNhTR t I. Mortality Lethal Acclination Data Te perature(F) Life State Extosure Tine Tenoevature Source 84.2-86 adult 64.4-71.6 Kinne(1970) I 77-78.8 adult 33.8-37.4 Kinne (19_70__) 3 41 adult 64.4-71.6 T.inne (1970) <31 adult 33.8-37.4 Kinne(1970) 84.2 adult deSylva(19_69) I z Data [' III. Reproductier.: ceticum Rance Month (s) Source Migratien Spawning 55-72 May-July Bigelev & I S chro ed er (19 5 3'. i Incubation /Eatch 55-6,5_ Data IV. Preferref Li f e S t a s;e Source 56 19 adult )_ricts(19731 g 4 I I I A-10 I

• • -e w

l

i TEMPERATUF2 DATA SREEI Species: OSMERUS MORDAX - RAI130W SMELT I. Mercality Lethal Ace 11mation Data Te=per ture(F) Life State Enosure Tit.e recoerature Source 10;7-83.3 adult 50-59 dc 5 vivagp_9,) I I I I I' I I l L gi I. Ii' A-ll

n B:

.1

i I TDJERAR*R.E DATA SHIC I i 1 Species: _MENIDIA MINIDIA - SILVERSIDE I. Mortality Lethal. Accli=a tion Data Te::erature(F) !.ife State Excesure Tire Tetterature Source j 73.4-77 1arvae 5-13 min 57.2 Coutant(1974) l S3.1-86.7 larvae $~13 :.in 69.8 Q,utant(1974) 90.3 adult 82.4 Hoff & _Ve s t an (19 66), S6.8 adult 69.6 _ Hoff & West an(1966) l 77 adult 57.2 Hoff & E Verpan(19661 l 71.6 sdult 44.0 Hoff 6 1 _ est:q (1966) Il 47.6 adult $2.4 Hott & ~ Vest =an(1966) l 39.8 adult 69.8 Hoff 6 Wes ::an (1966) i 35.6 adult 57.2 Hoff & ( _,Ve s t=a n (19 6 6 ) , I 34.7 adult 44.6 Hoff & ~ W s::an (1966], l1-98.4 adult 72.5 Gif: 6 West an(19711 98.9 adult 77.0 Gift & F; West an(1971) I BB adult 3 hr Batte11e-3ffo Acc11 cation Data IV. Preferred Life Stare Te eerature Source- _ _ _ adult _ 3 rives (19731 51-30 ' ~ 59 . adult 43 Meldri Gift (1971) -j 75 adult _ 70 Meldri Gift (1971) I h o:I .i A-12 s-ew.- -w.sr a-- e - - -,.i ein-- = m. ec- + o m-

~ TD'JEPJ.TUR?. DATA SKEET, 5pecies ALCSA PSEt"00KARENGUS - ALE'41FE I. Mortality Lethal Acclimation Data Temp erature(F) Life Stage, Exposure Time _ Tc=p e ra t.ur e Source 73.4 adult 90 hr 59 deSylva Q9M ) <44.6 adult. 72 hr 62.6 Stanley & Colby 88.6 adult Huntscan(1946) Opti=u= Data III. Reproduction: Te=perature . Range Month (s) Source Migration B Spawning Incubation / Hatch 60 Edsa11(19701 Acclia : ion Data IV. Preferred Life State M oerature Secree 71 adult 70 Meldrim & Gift (1971) B 68 adult 64 .I B 1 I I A-13

L> I I APPENDIX B & AT D h I It O' I I g 4, I I I I I

....N_ ~ ~. - ~ ,:,w. .#m ammenen wsm.es manuasp amannee m AFPLffJIK D LIST OF MfJt!NE ECOt4)CICA2, At4D fifDPAULTC STUDIF.O ASSOCIATED WITil P114RIN STATION Proicc(8 Con tr a ct er-Con sul t a nt - A*;e ncy Stody Periode f I Matlhe Ecology

1. ftirine Ecology surveys M.nss. Divistors of turina -

1969-1977 (fin fisle, Johster, fiel.eries. I plankton 5 trista poes)

2. Dentisic Stirlies

a. Raytheos Partne Lats.

1969-1970

h. Clagy lat=>ratory, pat e tle 1971-1974 Mcaunt lal Inst.

c. Dr. A. Flicleact (Mitt & T ale U.),

1*74-1977 g Dr. R. Wilce (u. Ma ne.).

3. Ichthyup14satton i

Survey of Cape Cod Day Marine 3esearcia, Inc. 1974-1976 4, Diological H.R.I. 1973-1975 Entralsweent. Stml1+s

5. Water Qu.311ty Dr. b. Carritt. (u. Mace.}.

1973 Measureuw*n ts

6. Tesaperature arm 1 CIM P 1,aloratory, 1972-1974 Chlorine Tolerance fiatelle Mesvarlal Institute.

Measur eusent s

7. Lif e siist ory St udy CocncIl Univ.

1969-1971 of giondrus crispus (J. Prince)

8. Nenhaden cas-nt*ble tiew England Aquaritsu 1974-1976 I

1blerance stuelles

9. Irish P&ms Wohn 1 tom oceanogras%r.

197R-1375 Quality Surveys 7nst. (Dr. J.II. Ryther). s

10. Pilgrims Unit. 1 Mass. Letr/PECO 1973-1975 Intake Monitoriref

11. Str-s/ of Alternative Yankee Atonalc Service 1975 Solertions te Mesd.aden Oce=pany/ EGG Attraction Prob!rre II Thermal Pl ea.no and Ocearungraphic Studies

1. Model nevejoseent and

a. MIT (tsr. O.R. Ilaricasan) 7972-1975 Predtrtions of Thermal

b. Dr. D.W. Pri t cleas d 1970-1974 Plume twbavir:n (Joia.s 2kyltins Univ.)

[ c rrr ranser nt 41 1974-75 g g M M M E E E N., En ivi rE E E E E E E ire

Q) %p e@* (O .s e' t A. %a IMAGE EVALUATION e /[/. t4p!g / s\\/o 'k[ 1hId TEST TARGET (MT-3) / jft .f E ' fgf'd' g\\)#,3 k'* 3 V+W $7<t 3 4e' B l.o it a a i;

• E g"' "n b IJa I,1 t in $L2R c

l!li} 1,8 I b-- ik!c= =. .!iy1.25_j a=.4 1 1=1.6 hii 2 4 150mm 6" h+eA* s,f>4 Q a, e 'hj?r <. g, p/, s,. m v

1. [b"w o.,

c 1 s.. i_,,- ((,~ 'u_____ a

&, s <e e. fy* <g 49 l e.' ,fgoh r ti V ? W}" A 4 IMAGE EVALUATION e ,'y [ f2 g/ g

• t)#@

TEST TARGET (MT-3) g J t s %Jr 9p?"

• • tq f f

'WP 4e 1.0 Em M unag,a n yg j,l fD b!db gg =e 'l.25 l I.4 i.6 lam I= 4 150mm 4 6" 4 4, 4% #o,

1. m ty

+ 9 y ),,, y ,,g e,g o t in s_ ~d tid Ch

u h/ 9 0 % p% 4e& sc e -o9,@][ V [+[f7 '\\ TEST TARGET (MT-3) IMAGE EVALUATION / N 49 'I g

• f g

gy, 4 4>, j& dj 9 + <v I.0 E 2 Ela . !,.?,4 L2g 't 4 = - - t: 11 l1[ k l.25 1.4 1.6

== m =__ 4 150mm 6" 44 es4$-Am 4

{5f /k,p

$4 N' v% j ,f7"- --~~r-- N 77 e# a f gr. I$ai. ~.aushik0 je4 t

me m q _: w M WWWM M '~ W W W W T" W W W M ' M MM~M M APPLitt11I It iJ pirr*ft) Project. Contractor *Cvisultant-Agengy St emly Period

2. Field Measurenwants of Urif t 1 Tliersaal Plume 2a. Itori Sorveys

a. MIT 1972-1973 82. VAST, Inc.

Dec. 1972 c.IE. Oct. 1974 2 12. Aerial Infrared 4. O wst.1 Pesearcia O)rp. Dec. 1974 Surveys le. Aero-M.srine Seirveys, Inc. Aug. 197)

c. Divironment al Prut ectiorn Agency.

Sept.1974 oct. 1975 2c. Dye Release Studies

1. West in,gtw>use-tone f<esearcia 1971

2. Vast, Inc.

fec. ',972

3. trd:

Oct. 1974

3. Ocearinatraphic

a. MiHT 1968-1977 Heasurements is. Dulico-Mr. R. O'11agan 1973-1975 (amtsient t esaperature

c. fra; 1974-1975 arid currents) 1967

4. Astalyses Related a.tumes & Mrw>re to Ptiyeical Ocean-to. IT. D.W. Prltetaard (Jolwis 1970-1974 ogragdiy and Thermal Ibsekins ifniv.)

Pltsee (in adrlit iws

c. St eme & Wetest er Envis onmental 1974 t o al ove)

Engineer lsrp Division

d. Yankee ato ic Service 01.

1975 1971-1975 Ill Alt ernate Osoli.sg Iwc! t el Corp. Systesa Sttmlies IV 1mpact Analysis for St one & Webst er Divironmevital 1975 Selected Nrine Species f_rigineerirus Division (1) Refer t o Pilgrim Unit 1 armt 2 F_R and Pilgrims St at tor Semi-Annual Nrine t eological St udies f or scene dewa lption ar i Indiviths.nl stimly r esult s. (2) Inclusive gearle=1s incitatin; ext ensirns into t fie future setierever ctant rset ua l a rrarwyements leave facen sna le. 9-2 -}}