ML073330737

Annual Report, Entrainment Survival and Related Studies.

ML073330737
Person / Time
Site:	Indian Point
Issue date:	01/31/1982
From:	Ecological Analysts
To:	Consolidated Edison Co of New York, Office of Nuclear Reactor Regulation, Power Authority of the State of New York
References
Download: ML073330737 (110)

Text

YI'.

..lINDIAN POIN GNERATING' STAT'O

-ENTRAINEN SUVVLAD ELATED(STUDIES' I 19.80.ANNUAL REPORT -

.. **;:.... . 1....:: .*.. -. - . . '. .... *.*  :. , "IJ I*,~rA , **~

i-. .* '.::ii:::.*.!.,,

. *. :..::: . -: ";i * * ?::* . .":,.' - :'".,:::ECOLOGICAL . ... ,*.; *:. - !. .*!i *. ".* .. . '.* .'!."

/~iti ....... .. /. .-. ,: *t ANALYS.TS...:... t , .:'L--.. *;' W '*.*.5 YorM,

• '";:* "*.';"*.':'..5"' - *": .

• : .. *"""'." "-""'*... .;"""" -?:' '*'.::*":.'""" N . "  ; i *""""'" .' .  :*: '* -. " ' -' -*.".:. ".. *.. .*'

..:-,,T *.*."*.

• ,*: .?..,*. 'j * .:*S .***" ,. .'?::..' .".?.,.'.. :: .C(: :': .*.' .,:.*..'..")*" '  ?."!*i~i:.".;:i :*.i:: ... o,*..,I-NYrX,/NVEW~R 10019,-

":: "i*,.:*:.:.

."": I2

".:.:  :*." .:. .* ' . '. . '.. .:: . ,:;.. N-NALN I- NC

EA Report CONO4K2 INDIAN POINT GENERATING STATION ENTRAINMENT SURVIVAL AND RELATED STUDIES 1980 ANNUAL REPORT Prepared for Consolidated Edison Company .of New York, Inc.

4 Irving Place New York, New York 10003 and Power Authority of the State of New York 10 Columbus Circle New York, New York 10019 Prepared by Ecological Analysts, Inc.

R.D. 2, Goshen Turnpike Middletown, New York 10940 January 1982

CONTENTS Page

1. INTRODUCTION 1.1 Perspective 1-1 1.2 1980 Entrainment Survival Studies 1-3 1.3 Scope of Report 1-3

2.

SUMMARY

2-1 2.1 Entrainment Survival Study 2-1 2.2 Sampling Flume Calibration Study 2-3

3. SITE DESCRIPTION 3.1 The Hudson River 3-1 3.2 The Indian Point Generating Station 3-1

4. ENTRAINMENT SURVIVAL STUDIES 4-1 4.1 Introduction 4-1 4.2 Methods and Materials 4-1 4.2.1 Sampling Procedures 4-1 4.2.1.1 Sampling Schedule and Station Locations 4-1 4.2.1.2 Gear Description 4-2 4.2.1.3 Collection Procedures 4-8 4.2.1.4 Water Quality Measurements 4-9 4.2.2 Sample Processing 4-9 4.2.2.1 Sorting Procedures 4-9 4.2.2.2 Extended Survival Observation Procedures 4-12 4.2.2.3 Quality Assurance and Control 4-12 4.2.3 Analytical Procedures 4-12 4.2.3.1 Survival Proportions 4-12 4.2.3.2 Entrainment Survival Estimates 4-14 4.3 Results and Discussion 4-14 4.3.1 Collection of Ichthyoplankton for Survival Determi nation 4-15 4.3.2 Survival Proportions 4-24 4.3.2.1 Survival of Striped Bass Eggs 4-24 4.3.2.2 Initial Survival at the Intake Station 4-28 4.3.2.3 Initial Survival at the Discharge Station 4-30

CONTENTS (CONT.)

Page 4.3.3 Extended Survival Proportions 4-34 4.3.4 Entrainment Survival Estimates 4-36 4.3.4.1 Atlantic Tomcod Juveniles 4-36 4.3.4.2 Striped Bass 4-40 4.3.4.3 White Perch 4-40 4.3.4.4 Herrings 4-40 4.3.4.5 Anchovies 4-41 4.3.4.6 Comparison of 1980 Entrainment Survival Data with 1977, 1978, and 1979 Results 4-41 4.3.5 Entrainment Survival as a Function of Size 4-45 4.4 Implications of the 1980 Entrainment Survival Results 4-50

5. ENTRAINMENT SAMPLING GEAR CALIBRATION STUDY 5-1 5.1 Introduction 5-1 5.2 Methods 5-1 5.2.1 Field and Laboratory Procedures 5-1 5.2.2 Analytical Procedures 5-2 5.2.2.1 Survival Proportions 5-2 5.2.2.2 Determination of Gear Effects 5-3 5.3 Results 5-4 5.3.1 Initial Survival 5-4 5.3.2 Extended Survival 5-18 5.4 Discussion 5-18 REFERENCES APPENDIX A ESTIMATED CIRCULATING WATER FLOW AT UNITS 1, 2, AND 3 APPENDIX B GEAR SPECIFICATIONS AND SAMPLING CONDITIONS APPENDIX C LENGTH-FREQUENCY DISTRIBUTION DATA

LIST OF FIGURES Number Title 3-1 Location of the Indian Point Generating Station relative to other generating stations on the Hudson River Estuary.

3-2 Diagram of the Indian Point Generating Station circulating water system showing location of sampling stations.

3-3 Indian Point Generating Station discharge structure.

4-1 Design of the collection flume used in the pumpless and rear-draw samplers during the entrainment survival study, Indian Point Generating Station, 1980.

4-2 Basic configuration of the pumpless plankton sampling flume system used at the discharge port during the entrainment survival study, Indian Point Generating Station, 1980.

4-3 Rear-draw plankton sampling flume system used at the Unit 3 intake during the entrainment survival study, Indian Point Generating Station, 1980.

4-4 Work-flow chart for ichthyoplankton survival determinations.

4-5 Discharge temperatures at the Indian Point Generating Station during 1980 entrainment sampling season.

4-6 Temporal distribution and thermal exposure of Atlantic tomcod collected at the discharge port station during the spring-summer entrainment survival study, Indian Point Generating Station, 30 April - 10 July 1980.

4-7 Temporal distribution and thermal exposure of striped bass collected at the discharge port station during the spring-summer entrainment survival study, Indian Point Generating Station, 30 April - 10 July 1980.

4-8 Temporal distribution and thermal exposure of white perch collected at the discharge port station during the spring-summer entrainment survival study, Indian Point Generating Station, 30 April - 10 July 1980.

4-9 Temporal distribution and thermal exposure of anchovies collected at the discharge port station during the spring-summer entrainment survival study, Indian Point Generating Station, 30 April -. 10 July 1980.

LIST OF FIGURES (CONT.)

Number Title 4-10 Temporal distribution and thermal exposure of herrings collected at the discharge port station during the spring-summer entrainment survival study, Indian Point Generating Station, 30 April - 10 July 1980.

4-11 Striped bass egg survival by sampling week at the Indian Point Generating Station, 1980.

4-12 Extended survival of Atlantic tomcod juveniles collected at Station 13 and Station DP at discharge temperatures <26 C and >27 C, Indian Point Generating Station, 1980.

4-13 Initial survival as a function of size for striped bass larvae at the Indian Point Generating Station, 1980.

4-14 Initial survival as a function of size for white perch larvae at the Indian Point Generating Station, 1980.

4-15 Estimates of initial entrainment survival as a function of size for white perch and striped bass larvae at the Indian Point Generating Station, 1980.

5-1 Intake and discharge station gear effects on the survival of hatchery-reared striped bass larvae as a function of length at the Indian Point Generating Station, 1980.

LIST OF TABLES Number Title 3-1 Average calculated transit times for cooling water during full flow operation of Indian Point Generating Station--Units 1, 2, and 3 operating individually and simultaneously.

3-2 ýPredicted temperature rise of condenser cooling'water at Unit 2, Indian Point Generating Station.

3-3 Predicted temperature rise of condenser cooling water at Unit 3,

.Indian Point Generating Station.

4-1 Circulating pump operation and electrical output by unit during entrainment survival sampling at the Indian Point Generating Station, 1980.

4-2 Average temperature, dissolved oxygen, pH, and conductivity recorded at Station 13 during the entrainment survival study, Indian Point Generating Station, 1980.

4-3 Total number of each ichthyoplankton taxon and life stage collected during entrainment survival sampling, Indian Point Generating Station, 1980.

4-4 Survival proportions based on hatching success for striped bass eggs collected during entrainment survival sampling, Indian Point Generating Station, 1980.

4-5 Results of three-way contingency analysis for independence among stations, survival, and sampling weeks for striped bass eggs collected at the intake and discharge stations during entrainment survival sampling at the Indian Point Generating Station, 1980.

4-6 Initial survival proportions for ichthyoplankton collected at the intakes of the Indian Point Generating Station, 1980.

4-7 Initial discharge station survival and entrainment survival estimates for Atlantic tomcod juveniles, as a function of discharge water temperature, Indian Point Generating Station, 1980.

4-8 Initial survival proportions for ichthyoplankton as a function of discharge water temperature, Indian Point Generating Station, 1980.

4-9 Initial survival for anchovy post yolk-sac larvae collected at discharge temperatures >33 C at Indian Point Generating Station, 1977-1980.

LIST OF TABLES (CONT.)

Number Title 4-10 Normalized extended survival proportions for ichthyoplankton collected during entrainment survival sampling, Indian Point Generating Station, 1980.

4-11 Entrainment survival estimates for dominant ichthyoplankton collected at Indian Point Generating Station, 1980.

4-12 Total number of important ichthyoplankton species collected at the discharge stations of the Indian Point Generating Station during spring-summer entrainment survival sampling, 1977-1980.

4-13 Entrainment survival estimates for ichthyoplankton occurring at and above typical summer discharge exposure conditions, Indian Point Generating Station, 1977-1980.

5-1 Hatching success and initial survival proportions for hatchery-reared striped bass eggs and larvae from the flume calibration study at Indian Point Generating Station, 1980.

5-2 Pooled initial survival proportions and estimates of sampling gear effects for hatchery-reared striped bass eggs and larvae from the flume calibration study at Indian Point Generating Station, 1980.

5-3 Initial survival and estimated gear effects by length categories for hatchery-reared striped bass larvae from the flume calibration study at the Indian Point Generating, Station, 1980.

1. INTRODUCTION 1.1 PERSPECTIVE The Indian Point Generating Station uses a once-through cooling system to dissipate waste heat. In the process, cooling water from the Hudson River is pumped through condensers where heat from steam leaving the turbine is transferred to the cooling water, which is returned to the river. The two electric power generating units in operation at the 3

Indian Point Generating Station withdraw up to.-'6,360 m /mnin (1.68 x 106 gpm) of water from the Hudson River for cooling'_ purpo-sc-se.- Aquatic organisms small enough to pass through the 9.5-mif-bar mesh intake screens may be carried through the cooling water system (entrained) where they are exposed to abrupt changes in temperature and hydrostatic pressure, mechanical buffeting, and velocity shear forces. Determining the survi-val of these organisms following entrainment is an important step in assessing potential effects of power plant operation on the aquatic environment.

Studies to examine survival of ichthyoplankton entrained through the condenser cooling water system of the Indian Point plant have been con-ducted throughout most of the past decade. Over the course of these studies, various sampling gear have been used and tested to assess biases associated with collection procedures, and to further minimize stresses associated with sampling. The results of entrairnent studies at Indian Point have been instrumental in supporting and promoting state-of-the-art developments in entrainment survival sampling and assessment.

The use of stationary nets at the Indian Point plant to assess survival of entrained organisms was based on the assumptions that sampling stress for organisms captured by nets was the same in the discharge canal as in the lower velocity intake (control) stations, and that mortality caused by the sampling nets was not significant (NYU 1976). However, net entrainment sampling conducted at Indian Point in 1972 revealed that differences in the velocity of water at intake and discharge sampling stations may have an effect on ichthyoplankton survival (NYU 1973). To examine the relationship between water velocity and survival of ichthyo-plankton captured in plankton nets of the type used at Indian Point, tests were conducted using early life stages of hatchery-reared striped 4 bass from Hudson River brood stock (NYU 1976; O'Connor and Schaffer 1977). These studies demonstrated that survival for the striped bass eggs and larvae was velocity-dependent. Survival for these life stages was considerably higher at 0.15 m/sec than at 0.46 m/sec. Water veloci-ties of 0.91 m/sec (3.0 fps) caused virtually complete mortality to all life stages. Yolk-sac larvae were found to be most sensitive to net

• Unit 1 has not operated for commercial production since October 1974.

Unit 2 is owned and operated by Consolidated Edison Company of New York, Inc. (Con Edison). Unit 3 is owned and operated by the Power Authority of the State of New York.

1-1

capture, followed by post yolk-sac larvae and egqs, in order of decreas-ing sensitivity. It was concluded that entrainment survival estimates for ichthyoplankton collected with standard net capture techniques may be profoundly affected by differences in water velocities and that failure to account for net-induced mortality may result in excessively high impact assessments (NYU 1976; O'Connor and Schaffer 1977).

Entrainment survival studies at the Indian Point plant were expanded in 1977 and 1978 to include sampling gear specifically designed to eliminate the effects of intake and discharge velocity differences on survival.

These studies, conducted by Ecological Analysts, Inc. (EA), used pumps to transport water from sampling locations into a flume (pump/larval table) that reduced the velocity of water and concentrated the sample. The effects of entrainment on ichthyoplankton were estimated by comparing survival at discharge stations with survival at intake stations which served as controls on sampling and holding effects. This sampling gear and technique generally resulted in higher entrainment survival estimates for most taxa and life stages than were obtained using nets (EA 1978a; 1979a).

In spite of the refinements in entrainment survival estimates achieved using pump/larval table collection systems, the pumps can cause sampling mortality to eggs and juveniles. Of the eggs collected in the pump/

larval tables in 1977 and 1978, none survived. Experiments have demon-strated that up to 20 percent of striped bass juveniles are killed by passage through 10- to 15-cm diameter pumps during normal sampling operation, and mortality may be as high as from 30 to 70 percent for clupeid juveniles (EA 1979b).

During the 1979 sampling season, raft-mounted collection systems designed to eliminate stresses associated with pump sanpling were used at the Indian Point plant (EA 1981). The new collection systems utilized pres-sure-induced flow rather than pumps for sample delivery, but retained the velocity reduction aspects of a flume system. The discharge collection system, referred to as the pumpless plankton sampling flume, used the pressure created by the difference in water level between the discharge canal and the river to deliver the sample. A pressure differential was created within the flume system at the intake station by pumping water from behind the angled diversion screens in the partially submersed flume. This gear is referred to as a rear-draw plankton sampling flume.

The floating support structures associated with the pumpless and rear-draw flumes offered additional advantages over the land-based pump/larval tables because the new systems could be placed near the point of sample withdrawal. Flotation of the discharge collection system provided a practical solution to sampling at the submerged discharge ports, which allows for evaluation of the effects of the entire entrainment process.

Results obtained with the pumpless and rear-draw plankton sampling flumes in 1979 (EA 1981) provided valuable new information on entrainment survi-val. Estimated survival of striped bass eggs was 74 percent, in contrast to previous years when there was no egg survival. For most larval groups discharge survival proportions were higher than for the pump/larval table collection systems used in 1978. However, unanticipated differences in sampling stress between the rear-draw and pumpless plankton sampling 1-2

flumes resulted in a greater sampling effect at the intake (control) station for most larvae. Sampling the rear-draw flume at the intake was apparently more stressful to most larvae than the combined effects of entrainment and sampling experienced by fish collected in the pumpless flume at the discharge. This differential gear effect was found to be length-related, based on the results of collection system calibration experiments (EA 1981). The calibration experiments indicated that the rear-draw flume caused higher sampling mortality for striped bass larvae from approximately 4 to 10 mm in length than did the pumpless flume; differences in sampling mortality declined as larvae approached 11 mm and were not apparent for striped bass eggs. These findings precluded the use of intake survival to adjust for sampling effects in estimating entrainment survival (Se) of larval stages collected in 1979.

Differences in sampling stress between the two collection systems in 1979 were likely caused by differences in water flow through the flume diver-sion screens during sampling or draining. The proximity of the pump intake manifolds to the diversion screens in the intake flume may have resulted in localized areas of high velocity flow through the screens, thus increasing the potential for impingement. No pump was required to induce water flow through the discharge flume; consequently, flow through the diversion screens of this sampler was more likely to be uniform.

Additionally, the drain rate was typically faster at the intake station because the rear-draw (intake) flume could be raised to facilitate drain-ing but the pumpless (discharge) flume could not. This situation may have resulted in higher water velocities through the diversion screens of the rear-draw flume and an increased likelihood of physical damage during the draining process.

1.2 1980 ENTRAINMENT SURVIVAL STUDIES To correct probable sources of differential gear effects, the rear-draw and pumpless plankton sampling flumes used in 1980 were modified with flow diffusion panels and slotted standpipes installed behind the angled diversion screens. These refinements were designed to more evenly dis-tribute water flow across the surface of the screens and eliminate localized areas of high velocity flow that may cause impingement on the screens. In addition, the gravity drain procedures applied in 1979 were discontinued in favor of a pump drainage system which allowed for control and standardization of the drain rates between the intake and discharge collection fl umes.

1.3 SCOPE OF REPORT This report presents the results of the 1980 entrainment survival and gear calibration studies conducted at the Indian Point Generating Station. The target taxa collected were striped bass (Morone saxatilis),

white perch (Morone americana), herring (Clupeidae), and anchovies (Engraulidae)7.7iilysis of juvenile Atlantic tomcod (Microgadus tomcod) was also undertaken because unusually large numbers of this species and life stage were collected during 1980 sampling. Entrainment survival was estimated for these taxa for several discharge temperature ranges. The results of the 1980 studies are also discussed with regard to the signi-ficance of organism size on entrai nment survival. In addition, potential 1-3

biases to entrainment survival estimates were evaluated by comparing sampling stress at the intake and discharge flumes.

Supplemental information is contained in the Appendixes. Estimated cir-culating water flow is presented in Appendix A. Design specifications of the sampling gear are provided in Appendix B. Length-frequency data in Appendix C are provided for the five major taxa analyzed.

1-4

2.

SUMMARY

2.1 ENTRAINMENT SURVIVAL STUDY Entrainment survival sampling was conducted at the Indian Point Genera-ting Station from 30 April to 10 July 1980. Sampling focused on entrainable life stages of striped bass (Morone saxatilis), white perch (M. americana), herrings (Clupeidae), and anchovies (Engraulidae). In addition, juvenile Atlantic tomcod (Microgadus tomcod), were also col-lected in sufficient numbers for analysis.

Raft-mounted collection flumes were positioned at the Unit 3 intake (Sta-tion 13) and at the first discharge port (Station DP). The flume systems were designed to reduce sampling stress by eliminating passage of the organisms through sampling puups. At the intake station, water was drawn into the flume by pumping water from behind the diversion screens. At the discharge station, the difference in water level between the dis-charge canal and the river was used to deliver the sample. Although the basic design of the flumes was similar to the systems used in 1979, modi-fications were made to eliminate differences in collection stress between the flumes. These modifications included (1) installation of baffles and slotted standpipes at the primary water outlets to uniformly distribute water flow through the diversion screens and (2) use of pump drainage systems at both flumes so that drain rates could be controlled.

Except for intermittent shutdowns, Units 2 and 3 operated consistently throughout the sampling season. Cooling water flow was somewhat lower than in previous years as only five circulating pumps per unit were generally operated. The lower flow resulted in higher than normal dis-charge temperatures and provided the opportunity to collect statistically meaningful numbers of organisms at temperatures in excess of 33 C.

Striped bass were the most abundant ichthyoplankton taxon collected in the 1980 entrainment survival study at the Indian Point Generating Sta-tion, followed by anchovies, white perch, Atlantic tomcod, and herrings (Section 4.3.1). Unusually low precipitation in winter and. spring 1980 resulted in higher than normal salinities during the sampling season, which may have caused the higher abundance of juvenile tomcod and lower abundance of herring compared to previous years. Post yolk-sac larvae were again the most frequent life stage collected, although striped bass eggs and yolk-sac larvae and juvenile Atlantic tomcod were also collected in numbers sufficient for survival analysis.

Initial survival proportions at the intake station were the highest yet achieved for ill taxa'(Section 4.3.2). Survival ranged from 0.323 for anchovy post yolk-sac larvae to 1.000 for juvenile Atlantic tomcod.

White perch:post yolk-sac survival was 0.929 while striped bass survival ranged from 0.816 for eggs to 0.953 and 0.951 for yolk-sac and post yolk-sac larvae, respectively. These extremely high survival proportions suggest that the gear modifications made before the 1980 season were extremely successful in reducing sampling stress.

2-1

Initial survival at the discharge station also compared favorably with previous data, particularly when examined over the established tempera-ture ranges (Section 4.3.2). Survival in 1980 was the highest yet observed for eight of ten life stage-temperature groups studied. Notably high survival proportions were: 0.877 for Atlantic tomcod juveniles collected at temperatures <26 C, 0.469 for striped bass eggs (.all tem-peratures combined), 0.550-for striped bass post yolk-sac larvae (>33 C),

and 0.898 and 0.496 for white perch post yolk-sac larvae collected at temperatures <29 C and >33 C, respectively. The extremely high survival proportions achieved for discharge temperatures <32 C indicate that sur-vival of entrained organisms can be quite high ff thermal stress is not severe.

The extended survival in 1980 was higher than in previous years (Section 4.3.3). Survival at the two sampling stations was generally similar, so latent effects of entrainment were not detectable for striped bass, white perch, herrings, and anchovy. Survival of organisms sampled at intake and discharge stations was significantly different (a = 0.05) only for juvenile tomcod The significant difference for these larger organisms (generally >25 mm TL) may be due to increased physical stress during pump or condenser passage.

Entrainment survival estimates for the 1980 study were extremely valuable in examining the effects of thermal stress (Section 4.3.4). Survival estimates for organisms entrained at temperatures below where thermal stress should occur, <32 C, ranged from 12 percent for anchovy post yolk-sac larve to 91 percent for white perch post yolk-sac larvae.

Entrainment survival at temperatures below 33 C for striped bass varied from 58 percent for eggs to 65 percent for yolk-sac larvae and 80 percent for post yolk-sac larvae. Entrainment survival of juvenile Atlantic tomcod below thermal stress conditions (<_26 C) was 88 percent based on initial survial proportions, or 66 percent based on 24-hour survival since latent effects were observed. At high discharge temperatures,

>33 C, entrainment survival was 58 percent for striped bass and 53 per-cent for white perch post yolk-sac larvae. These survival values are higher than would be expected from laboratory thermal tolerance studies.

Entrainment survival of white perch and striped bass increased with size of the larvae (Section 4.3.5). Survival estimates at low discharge tem-peratures approached 100 percent when larval length exceeded 12 mm for both species. The survival of smaller larvae was extremely variable, but generally less than 60 percent. Above discharge temperatures of 33 C, survival also increased with length, but reached a naximum near 60 per-cent.

The success at reducing sampling stress in 1980 was important in dismis-sing potential biases in entrainment survival (S ) estimates (Section 4.4.1). Greater sampling stress at Station 13 wIuld cause an overesti-mate of entrainment survival and greater sampling stress at Station DP would cause an underestimate of entrainment survival. Previous Se estimates were subject to station differences in sampling stress, which could introduce a bias. For example, in 1979 sampling bias was clearly more stressful at the intake station, which prevented adjustment for sampling stress of data collected at the discharge station. In 1980, 2-2

however, sampling stress at the intake station was reduced to such a low level that overestimating entrainment survival was not possible. The entrainment survival 'values in 1980 are likely to be conservative and underestimate the actual survival, if any bias exists.

2.2 SAMPLING FLUME CALIBRATION STUDY Sampling flume calibration experiments to assess sampling stress on entrainable life stages of striped bass were conducted in conjunction with the entrainment survival study. Calibration experiments used hatchery-reared eggs and larvae to estimate the probability of surviving sampling at each station.

Statistically significant gear effects were found for eggs in both flumes and for yolk-sac and post yolk-sac larvae at the discharge flume. Large sample sizes (generally >300 organisms) allowed extremely powerful statistical tests which detected small, but significant, gear effects for eggs at Stations 13 and DP, and yolk-sac larvae and post yolk-sac larvae at Station DP. Gear effect ratios indicate a maximum underestimate (bias) of about 16 percent for the entrainment survival of yolk-sac lar-vae. The potential bias for striped bass eggs and post yolk-sac larvae entrainment survival was small, only a 4 percent overestimate and a 2 percent underestimate, respectively. As in 1979, the potential sampling bias was greatest for small larvae. For larvae <10 mm, gear effects were detectable at Station DP. Sampling stress was undetectable for larvae of any size at Station 13.

2-3

3. SITE DESCRIPTION 3.1 THE HUDSON RIVER The Hudson River, located in southeastern New York state, is a 496-km long river and tidal estuary, originating at Lake Tear of the Clouds and terminating at New York City. The non-tidal portion of the river extends 246 km from *ts origin to the Green Island Dan at Troy and drains an area of 11,000 km . The tidal estuary extenos 250 km from Troy to New York City and drains an additional 14,000 kmn (Figure 3-1).

Near the Indian Point Generating Station, located 69 km north of the Battery at Buchanan, New York, the Hudson River is approximately 1,500 m wide and has a cross-sectional area of 15,000 in. River depths range fram 3 to 12 m within 60 m of the plant.

Water movement in this section of the river is primarily tidal. Mean tidal flows are approx mately 4,000 m3 /sec and mean monthly freshwater flows range from 160 mrn/sec in August to 900 m3 /sec in April (Con Edison 1977a, p. 2-1). Seasonal trends in salinity vary with freshwater flow.

Dgring March, April, and May when freshwater flow generally exceeds 500 m /sec, the salt front (defined as 0.1 ppt salinity) usually remains downriver from the Indian Point Generating Station. During periods of low freshwater flow, generally from July through October (Con Edison 1977a, Table 2-2), salinity may fluctuate rapidly as the salt front moves upriver into the vicinity of Indian Point. Mean ambient river tempera-tures in the Indian Point area range fran 0.7 to 25.0 C throughout the year (Con Edison 1977a, Table 2-3).

3.2 THE INDIAN POINT GENERATING STATION The Indian Point Generating Station consists of three nuclear-fueled electric generating units. Unit 1 is owned by Con Edison and has not operated for cammercial production since October 1974, although its circulating water and service water pumps are operated occasionally.

Unit 2, owned and operated by Con Edison, has been in operation since 28 September 1973 and has a net rated capacity of 873 MWe. Unit 3 is owned and operated by the Power Authority of the State of New York and has been in operation since 30 August 1976. It has a net rated capacity of 965 MWe. All three units use Hudson River water for once-through cool i ng.

Each unit has a separate shoreline intake structure for withdrawal of water from the Hudson River (Figure 3-2). The intake structure for Unit 1 has four rectangular ports extending 8 m below mean low water. The intake structures for Units 2 and 3 each have six intake ports, also extending 8 m below mean low water.: Units 1 and 2 are equipped with fixed screens at the entrance to the intake bays and vertical traveling screens behind the fixed screens. The Unit 3 intake only has vertical traveling screens at the entrance to the intake bays. All screens are 9.5-mm bar mesh, with the exception of an experimental fine mesh (2.5 mm) traveling screen located at the Unit 1 intake.

3-1

Figure 3-1. Location of the Indian Point Generating Station relative to other generating stations on the Hudson River Estuary (Scale - 1:1,267200).

Unit 3 UnIt 2 Condensers Condensers 3 2 3 2.1 N

Condenser I) P mliNn 73InSO8lIE ake 1on Intake

,-." *,,,-,,-,,-, _..Intake bay numbers Wharf IIUDSON RIVER Upstream Station circulating water system showi .nglocation of Figure 3-2Z Diagram of the Indian Point Generating sampling stations (from Con Edison 1977b).

Circulating water pumps with rated capacities of 530 m3 /min are used to pump Hudson River water through the condenser cooling system of each unit. Unii 1 has two circulating water pumps capable of pumping a total of 1,060 m /min, ind two service water pumps with a combined rated capacity of 144 m /min. Units 2 and 3 each have six circulating water pumps, one for each intake bay (Figure 3-2). The circulating water systems for Units 2 and 3 are designed to operate at either 100 or 60 percent of maximum flow. When the ambient water temperature is above 4.4 C (spring through fall), the cooling water flow for each unit is approximately 3,200 m3 /min. During the winter, 40 percent of the cooling water is returned to the circulating pumps without passing through the condensers, thus reducing the water withdrawal to 1,900 m-3/min. Service water for Units 2 and 3 is drawn through a separate intake forebay at the center of each intake §tructure; the maximum total service water flow for Units 2 and 3 is 114 mn/min.

The cooling water and service water from all three units flow into a common discharge canal. The combined discharge is returned to the Hudson River via a discharge structure (Figure 3-3) located at the shoreline downstream of Unit 3. The discharge structure is a steel-walled reser-voir with 12 submerged ports. The center of each port is 3.7 m below the river surface at mean low water.

Calculated transit times of cooling water traveling from intake to river outfall when Units 2 and 3 are operating at full pumping capacity is 9.7 minutes for Unit 2 and 5.6 minutes for Unit 3 (Table 3-1). Passage from the intake to the condensers is about 1.5 minutes and calculated time through the condensers is 0.14 minutes for both units. Thus, much of the total transit time through the cooling-water systems occurs in the dis-charge canal. Because the discharge canal receives cooling water from all three units, transit times through the canal depend on the total circulating water flow through all units.

The temperature rise (delta-T) encountered by organisms passing through the condenser cooling systems of the Indian Point Generating Station depends on the cooling water flow and level of power generation (Tables 3-2 and 3-3). At Unit 2, with six pumps operating at full flow and the unit at 100 percent generating capacity, the calculated condenser tem-perature rise ranges from 8.8 to 8.9 C, depending on river temperature.

At Unit 3, the calculated condenser temperature rise ranges from 9.5 to 9.7 C for 100 percent capacity generation with six pumps operating at full flow. -The higher calculated delta-T at Unit 3 is due to the higher rated generation capacity.

Both units were operating during the 1980 sampling season (late April through mid-July), except from 4 to 11 June, when Unit 2 was offline, and isolated days for Units 2 and 3 (Section 4.2.1). Cooling water flow was generally maintained during the unit outages. Only service water pumps were operating at Unit 1. Summaries of the total calculated water flow (service and cooling water) for each unit during the 1980 sampling season are presented in Appendix A.

3-4

/

7?I I-,

C, Z

0~

I%3 CD CDC CD

-CD 0

TABLE 3-1 AVERAGE CALCULATED TRANSIT TIMES FOR COOLING WATER DURING FULL FLOW OPERATION OF INDIAN POINT GENERATING STATION--UNITS 1, 2, AND 3 OPERATING INDIVIDUALLY AND SIMULTANEOUSLY Individual Operation (time in minutes)(a)

Unit 1 Unit 2 Unit 3 Intake to Common 33.23 12.85 8.77 Discharge Ports Simultaneous Operation of Units 2 and 3 (b)

(Unit 1 not operating)

Unit 2 Intake to Common Discharge Ports (time in minutes)

Circulating Pumps Circulating Pumps Operating at Unit 2 Operating at Unit 3 3 4 5 6 3 17.7 14.4 12.3 10.8 4 16.8 13.7 11.7 10.3 5 16.2 13.2 11.3 10.0 6 15.6 12.8 11.0 9.7 Unit 3 Intake to Common Discharge Ports (time in minutes)

Circulating Pumps Circulating Pumps Operating at Unit 2 Operating at Unit 3 3 4 5 6 3 9.6 8.3 7.4 6.7 4 8.7 7.6 6.8 6.3 5 8.0 7.1 6.4 5.9 6 7.5 6.7 6.1 5.6 (a) Source: NYU 1978, Table 1-1.

(b) Source: Personal Communication; Consolidated Edison Company of New York, Inc., 10 January 1980.

Note: Calculated transit times are based on pumps operating at 100 per-cent flow (312 cfs); calculated transit time through condenser:

0.14 minutes.

TABLE 3-2 PREDICTED TEMPERATURE RISE (C) OF CONDENSER COOLING WATER AT UNIT 2. INDIAN POINT GENERATING STATION Pumps Operated With Pumps Operated With PI ant River No Recirculation 40% Recirculation Capacity (MWe) Temperature (C) 6 Pumps 5 Pumps 4 Pumps 3 Pumps 6 Pumps 5 Pumps 4 Pumps 3 Pumps 906 (100% load) 4.4 -- -- -- 14.6 17.6 22.6

• 10.0 8.8 10.4 13.1 17.9 14.7 17.7 22.7

• 15.6 Sa 1"n r, 1il 1 0 l 1 1 .....

21.1 8.9 10.6 13.2 26.7 8.9 10.7 13.5 766 (75% l oad) 4.4 12.6 15.2 19.1 24.4 10.0 7.5 9.1 11.4 15.3 12.7 15.3 19.2 24.4 15.6 7.6 9.1 11.5 15.4 21.1 7.6 9.2 11.6 15.7 26.7 7.7 9.2 11.7 510 (50% load) 4.4 10.8 8.8 10.7 13.4 17.2 10.0 5.2 6.4 8.1 8.9 10.8 13.5 17.2 10.8 15.6 5.3 6.4 8.1 21.1 5.3 6.5 8.2 11.0 26.7 5.4 6.6 8.2 11.2

• Turbine backpressure higher than 3.5-in. Hg.

Dash (--) indicates operating mode not appropriate at these temperatures.

Source: Con Edison 1977a.

TABLE 3-3 PREDICTED TEMPERATURE RISE (C) OF CONDENSER COOLING WATER AT UNIT 3, INDIAN POINT GENERATING STATION Pumps Operated With Pumps Operated With P1 ant River No Recirculation 40% Recirculation Capacity (MWe) Temperature (C) 6 Pumps 5 Pumps 4 Pumps 3 Pumps 6 Pumps 5 Pumps 4 Pumps 3 Pumps 1,000 (100% load) 4.4 -- 16.0 19.3 24.7 10.0 9.5 11.5 14.3 19.6 16.2 19.4 24.8 15.6 9.6 11.6 14.4 19.8 21.1 9.6 11.6 14.5 26.7 9.7 11.7 14.8 766 (75% load) 4.4 12.6 15.2 19.1 25.6 10.0 7.5 9.1 11.4 15.3 12.7 15.3 19.2 25.6 15.6 7.6 9.1 11.5 15.4 21.1 7.6 9.2 11.6 15.7 26.7 7.7 9.2 11.7 510 (50% load) 4.4 10.8 8.8 10.7 13.4 18.3 10.0 5.2 6.4 8.1 10.8 8.9 10.8 13.5 18.3 15.6 5.3 6.4 8.1 21.1 5.3 6.5 8.2 11.0 26.7 5.4 6.6 8.2 11.2

• Turbine backpressure higher than 3.5-in. Hg.

Dash (--) indicates operating mode not appropriate at these temperatures.

Source: Con Edison 1977a.

4. ENTRAINMENT SURVIVAL STUDIES

4.1 INTRODUCTION

The 1980 entrainment survival study was designed to determine the survi-val of ichthyoplankton passing through the condenser cooling systems of the Indian Point Generating Station. This study represents a continua-tion of studies conducted by.Ecological Analysts in 1977, 1978, and 1979 'A *

(EA 1978a, 1979a, and 1981). The 1980 study focused on the entrainment survival of striped bass (Morone saxatilis), white perch (M. americana),

herrings (Clupeidae), and anchovies (Engraulidae) which use the Hudson River estuary as a spawning and nursery area during spring and summer months. Unusually large collections of juvenile Atlantic tomcod (Micro-gadus tomcod) also allowed for an analysis of entrainment survival for this winter spawning taxon.

Although pump/larval table collection systems were used for the 1977 and 1978 survival studies and the late winter Atlantic tomcod study in 1979, a new gear design was implemented during the 1979 spring-summer sampling effort to further reduce sampling stress on more sensitive taxa and life stages. These new collection systems, the pumpless (discharge) and rear-draw (intake) plankton sampling flumes, strained organisms from the water without first passing them through a pump. Flotation of the samplers permitted closer access to the point of sample withdrawal and facilitated sampling at the ports of the discharge canal.

In 1980, additional modifications were incorporated in the flume sampling systems to eliminate the differences in sampling stress between flumes observed in 1979 (EA 1981). These modifications included altering water flow patterns across the diversion screens and standardizing the drain rates. The success of these modifications in controlling sampling stress was apparent in the 1980 data. Potential bias from sampling-related mortality has been practically eliminated and entrainment survival esti-mates were thus superior to any of the previous estimates. The increased quality of the data allowed a reexamination of previous ideas concerning the effect of entrainment at the Indian Point Generating Station on aquatic organisms.

4.2 METHODS AND MATERIALS 4.2.1 Sampling Procedures 4.2.1.1 Sampling Schedule and Station Locations Entrainment survival sampling for striped bass, white perch, herrings, and anchovies was conducted from 30 April through 10 July 1980, coinci-dent with the primary spawning and nursery seasons of these taxa.

Samples were collected on four consecutive nights each week (a total of 44 sampling days) between 1600 and 0200 hours0.00231 days <br />0.0556 hours <br />3.306878e-4 weeks <br />7.61e-5 months <br />. Throughout the entrain-ment survival study, sampling was conducted at discharge port number one (Station DP) using a pumpless plankton sampling flume and at the Unit 3 intake (Station 13) (Figure 3-2) using a rear-draw plankton sampling 4-1

flume. During the sampling period, Units 2 and 3 operated almost con-tinuously and Unit 1 did not operate (Table 4-1).

4.2.1.2 Gear Description The pumpless and rear-draw plankton sampling flumes used in 1980 were mounted on rafts and both systems collected organisms without first passing them through pumps. This design reduced sampling stresses on sensitive ichthyoplankton by eliminating mechanical and pressure effects associated with pump collection. Internal aspects of both flumes (e.g.,

length and width, orientation of the water inlet, flow expansion panels, diversion screens, ambient water injection systems, and collection box) were designed in the same manner (Figure 4-1) to minimize potential differential gear effects on organism survival.-

The pumpless flume at Station DP used the pressure created by the differ-ence in water level between the discharge canal and the river to deliver sample water. The flume was positioned along the outside of the dis-charge canal bulkhead adjacent to the northernmost discharge port (Figure 4-2). The sampler was secured to a raft so that the flume was maintained at the river surface. Water and organisms exiting the discharge port entered a 15-cm diameter curved steel pipe (Figure 4-2). The sample water then passed through a flexible hose to the inlet of the flume.

The water velocity at the discharge port (about 3 m/sec) was sufficient to deliver sample water to the collection flume. The temperature of the sample was reduced gradually in the discharge flume by an ambient water injection system that supplied a fine stream of ambient temperature river water along the sides of the flow expansion panels, diversion screens, and collection box. Temperatures in the collection box were typically 2 to 3 C below the temperature of water entering during sampling. Water flow through the sampler was primarily by gravity since the water level in the flume was above the river surface. The flow of water across the diversion screens was diffused by baffle plates mounted behind the screens and slotted standpipes at the primary outlets from the flume.

Flexible hoses attached to the primary outlets were raised or lowered to adjust water flow through the system and to alter the water depth within the sampler. Organisms and detritus filtered by the two vertical 505-um mesh screens were diverted into the collection box. Jiltered sample water was pumped at a constant rate (generally 0.15 m/min) from the collection system through the secondary outlet beneath the collection box. The volume of water sampled, which varied with the difference in water levels between the river and the discharge canal, was measured with a Signet inline flowmeter attached to the fl4me inlet. Sample volume averagid 16.9 m3 (standard deviation = 3.2 mi3 ) and ranged from 8.6 to 25.8 m per sample over the sampling season.

The rear-draw plankton sampling flume (Figure 4-3) was mounted on a raft in front of the Unit 3 intake structure. The design of the flume and collection box components of this sampler was consistent with the pumpless plankton sampling flume, and sample delivery was also achieved without passing the organisms through pumps. However, because the water velocity at this station (approximately 0.3 m/sec) was insufficient to supply an adequate sample flow, a water level difference was created wit hin the flume by submerging the bottom of the flume below the river 4-2

TABLE 4-1 CIRCULATING PUMP OPERATION AND ELECTRICAL OUTPUT BY UNIT DURING ENTRAINMENT SURVIVAL SAMPLING AT THE INDIAN POINT GENERATING STATION. 1980 Unit 2 (a) Unit 3 (a)

Circulating Average Daily Circulating Average Daily Sampling Pumps Kilowatt 3 Pumps Kilowatt Date Operating Generation (xlO ) Operating Generation (xlO )

30 .APR 852 4 603 1 MAY 845 4 606 5 MAY 852 4 607 6 MAY 851 5 645 7 MAY a50 5 790 8 MAY* 845 5 789

.12 MAY 839 5 880 13 MAY 845 5 882 14 MAY 847 5 880 15 MAY 848 5 879 19 MAY 627 3 311(b) 20 MAY 839 5 435 21 MAY 0001-1952 hours) 5 21 MAY 1952-2400 hours) 835 4 882 22 MAY 839 4 878 27 MAY 836 4 855 28 MAY 842 4 853 29 MAY (0001-2145 hours) 4 29 MAY (2145-2400 hours) 836 5 854 30 MAY 588(b) 837 5 2 JUN (0001-1900 hours) 5 2 JUN (1900-2400 hours) 820 5 809 3 JUN 500(b) 5 574 4 JUN 0 5 822 (a) Only Units 2 and 3 generated electricity and had circulating pumps operating during entrainment survival sampling.

(b) Electricity was not being generated during entra inment survival sampling on this day.

(c) Electricity was not being generated during the f irst two samples collected on this day.

(d) Electricity was not being generated during the I ast four samples collected on this day.

TABLE 4-1 (CONT.)

Unit 2 (a) Unit 3(a)

Ci rcul ating Average Daily Circulating Average Daily Sampl i ng Pumps Kilowatt Pumps Kilowatt 3 Date Operating Generation (xlO_) Operating Generation (x1O) 5 JUN 3 0 5 874 9 JUN 0 0 5 880 10 JUN 0 0 5 880 11 JUN 5 0 3 3 39 (b) 12 JUN 5 82 5 73(c) 16 JUN 5 841 5 877 17 JUN 5 839 5 877 18 JUN 5 839 5 879 19 JUN 5 838 5 878 23 JUN 5 837 5 875 24 JUN 5 833 5 871 25 JUN 5 834 5 870 26 JUN 5 832 5 866 30 JUN 5 830 5 683(d) 1 JUL 5 834 5 682 2 JUL 5 4 8 6 (b) 5 5344c) 3 JUL 5 479 5 449 7 JUL (0001-1815 hours) 5 .5 7 JUL (1815-2400 hours) 6 830 5 860 8 JUL 6 834 5 862 9 JUL 6 838 5 857 10 JUL 6 835 5 854

-I, 0

3?

CD-x CD a) 5.

V a)

CD

- .0 B

5. 0~

CD a)

CD CD

~

CD 00

It system used Figure 4-Z. Basic configuration of the pumpless plankton sampling flume at the discharge port (Station DP) during the entrainment survival study, Indian Point Generating Station, 1980.

IA "C

1. 11-1 Figure 4-3. Rear-draw plankton sampling flume system used at the Unit 3 intake (Station 13) during the entrainment survival study, Indian Point Generating Station, 1980.

surface and using a 10-cm (4-in.) Homelite pump to punp water from behind the diversion screens. The flow of water across the diversion screens was diffused with baffle plates and slotted standpipes similar to those in the pumpless sampling flume. Water was pumped from the collection box at the same rate as at the discharge sampler (0.15 m3 /min). A separate pump supplied filtered river water to the ambient water injection system.

Sample water entered the collection flume through a 15-cm diameter flex-ible hose attached to the flume inlet. The mouth of the hose, which faced into the Unit 3 intake flow, was suspended at a 3.4-m depth to match the depth of withdrawal at the discharge station. Volume sampled was measured with an inline Sparling "Masterflo" flowmeter attached to the H melite pump. Sample volume averaged 15.5 mJ (standard deviation =

2.0 m ) and ranged from 11.0 to 21.0 m3 . Drain time ranged from 15 to 37 minutes per sample. (Specific information relative to sampling gear and associated sampling conditions at each station are presented in Appendix B, Table B-i).

4.2.1.3 Collection Procedures Each sample collected with the pumpless or rear-draw plankton sampling flumes was taken by allowing water to flow through the gear for 15 min-utes. Prior to sampling, the ambient water injection systems were activated to fill the collection flumes with filtered water, and the Homelite pump was started at the rear-draw sampler (Station 13).

Sampling was initiated simultaneously at the intake and discharge sta-tions by removing the plugs from the flume inlets. The pumping rate at the intake station was adjusted to conform to the flow (+/-100 t/min) at the discharge station. Similar water depth within the samplers was maintained by adjusting the flexible hoses attached to the primary out-lets of the pumpless flume, adjusting the pumping rate at the rear-draw flume, or adjusting the depth of submersion of the rear-draw flume.

At the end of the sampling interval, plugs were placed in the flume inlets and the Homelite pump was turned off at the rear-draw flume.

The ambient water injection systems remained on until the samplers were nearly drained to rinse the surfaces of the flow expansion panels, diversion screens, and collection boxes. Rinsing of the interior of the samplers was supplemented with a gentle flow of filtered ambient river water frqm a 19-mm diameter garden hose. Because the depths within the samplers were similar during sampling and the secondary outlet pumps removed water at the same rate, the time to drain each sampler was also similar. Once the samples were concentrated in the collection boxes, the pumps were stopped. Organisms and detritus were then drained into detachable transportation containers through 3-cm diameter tubing at the bottom of the collection boxes. The samples were transferred to the onsite laboratory for sorting. Between samples, flumes and collection boxes were thoroughly rinsed with a high pressure spray wash to prevent contamination of subsequent samples from detritus or organisms adhering to the surface of the sampler.

4-8

4.2.1.4 Water Quality Measurements Water temperature, conductivity, dissolved oxygen, and pH were measured each night. Water temperature was recorded at both stations during each sample collection. Conductivity, dissolved oxygen, and pH were measured within the flume at Station 13 during the first, middle, and last collec-tions on each sampling night. Water quality data collected at the intake station during the entrainment survival study is presented in Table 4-2.

4.2.2 Sample Processing 4.2.2.1 Sorting Procedures Live and dead ichthyoplankton were sorted from the transportation con-tainers immediately after sample collection and processed as indicated in Figure 4-4. Ichthyoplankton were classified as live, stunned, or dead according to the following criteria:

Live: Fish - swimming vigorously, no apparent orientation difficulty.

Eggs - translucent, chorion complete, not cloudy in any internal portion.

Stunned: Fish only - swimming abnormally, struggling, swimming on side or upside down; or nonmotile except when gently probed.

Dead: Fish - no vital signs, no body or opercular movement, no response to gentle probing.

Eggs - opaque, chorion ruptured or cloudy in any internal portion.

Dead eggs and larvae were removed from the sample and preserved in 5 per-cent buffered formalin. Live and stunned larvae were carefully trans-ferred with a spoon from the sorting trays to 1-liter jars of filtered ambient river water. A maximum of five specimens were placed in each holding jar. Young larvae were separated from the older larvae and juve-niles to reduce the possibility of cannibalism. The holding jars were aerated and maintained in an ambient temperature water bath for 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> after collection. Live eggs were carefully transferred from the sorting trays to egg holding cups, Holding cups were constructed of 10-cm diameter PVC pipe, 10 cm high, with a fine mesh screen bottom to permit ambient water circulation. Residual detritus and invertebrates from all the samples were preserved in 10 percent buffered formalin. Preserved specimens were transported to Ecological Analysts' Central Laboratory in Middletown, New York, for identification and classification according to taxon and life stage. The total length of each specimen was determined to the nearest millimeter.

4-9

TABLE 4-2 AVERAGE TEMPERATURE, DISSOLVED OXYGEN, pH, AND CONDUCTIVITY RECORDED AT STATION I3 DURING THE ENTRAINMENT SURVIVAL STUDY, INDIAN POINT GENERATING STATION, 30 APRIL -

10 JULY 1980 Temp. DO Cond.

Date (umho) pH 30 APR(a) 12.0 6.0 2,980 7.8 30 APR 11.3 9.5 1,819 7.7 1 MAY 12.0 10.4 774 7.7 5 MAY 13.2 10.0 536 7.6 6 MAY 13.6 9.8 248 7.6 7 MAY 13.8 9.6 184 7.3 8 MAY 13.8 9.3 150 7.5 12 MAY 15.1 13 MAY 15.7 8.4 136 14 MAY 15.6 8.9 136 7.9 15 MAY 15.5 7.7 161 7.4 19 MAY 16.5 7.2 232 7.4 20 MAY 16.9 7.7 249 7.4 21 MAY 17.1 7.9 181 7.4 22 MAY 17.6 7.9 1,116 7.4 27 MAY 18.5 7.4 6,592 7.4 28 MAY 18.7 7.5 6,028 7.4 29 MAY 19.0 6.2 6,926 7.4 30 MAY 18.3 6.1 6,897 7.3 2 JUN 19.2 6.1 6,332 7.4 3 JUN 19.7 6.2 5,930 7.3 4 JUN 19.6 8.1 6,375 7.1 5 JUN 20.3 7.8 5,056 7.0 9 JUN 20.0 8.1 5,391 7.4 10 JUN 19.9 7.9 3,863 7.3 11 JUN 19.7 7.6 3,335 7.3 12 JUN 19.9 7.6 2,995 7.2 16 JUN 21.5 7.6 2,873 7.4 17 JUN 21.7 7.8 2,686 7.5 18 JUN '22.3 7.6 3,155 7.4 19 JUN 22.7 7.8 3,360 7.5 23 JUN 23.2 7.6 4,688 7.5 24 JUN 23.0 8.1 4,517 7.6 25 JUN 23.5 7.9 4,605 7.6 26 JUN 23.3 7.7 5,147 7.5 30 JUN 23.4 6.9 4,890 7.4 1 JUL 23.6 6.8 4,923 7.4 2 JUL 23.6 6.8 4,925 7.4 3 JUL 23.8 6.7 5,211 7.1 7 JUL 25.1 6.6 5,480 7.1 8 JUL 24.7 6.2 4,457 7.2 9 JUL 25.0 6.5 4,057 7.2 10 JUL 24.9 6.5 3,956 7.2 Note: (a) indicates sample collection from the previous night; Dash (--) indicates data were not available.

Central Laboratory Processing Field Processing I

I.

I Latent Ellects Checks

3. 6, 12, 24,.48, and 72 hr I .

I II Figure 4-4. Work-flow chart for ichthyoplankton survival determinations.

4.2.2.2 Extended Survival Observation Procedures The survival of live and stunned ichthyoplankton was monitored for 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> after collection (Figure 4-4). Interim survival assessments (latent effects checks). were made 3, 6, 12, 24, 48, and 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> after collection. At each check, dead organisms were removed from the holding containers and preserved in vials containing 5 percent buffered forma-lin. All organisms remaining alive at the 96-hour check were enumerated and preserved. Live eggs collected during survival sampling were monitored for 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> after collection to determine hatching success.

Dead eggs were removed at each observation period. Larvae that had hatched were removed and preserved for later identification.

4.2.2.3 Quality Assurance and Control Quality assurance and control procedures were used throughout the sampling effort to ensure the accuracy of the data. Quality control procedures established at the onsite laboratory consisted of: (1) sorting efficiency checks immediately after the initial sort and, when eggs were present, an additional check to determine whether all eggs had been removed; (2) a color-coded labeling system for holding containers and vials; and (3) records of the number of live and dead fish, or hatched eggs, observed at each extended survival observation.

In addition, periodic inspections of the field sampling program were conducted by Ecological Analysts' Documentation Control Office to ensure adherence to standard operating procedures. Quality control procedures established at the Central Laboratory included re-sorting of randomly selected preserved samples to document the sorting efficiency at the onsite laboratory, and the application of statistical quality control procedures for an average outgoing quality limit (AOQL) of 0.10 for a continuous sampling plan (Duncan 1974) to ensure the precision of ichthyoplankton identification.

4.2.3 Analytical Procedures 4.2.3.1 Survival Proportions 4.2.3.1.1 Egg Survival The proportion of eggs that survived was determined on the basis of hatching success within 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> after collection:

PI or P =-No. of eggs which hatched within 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> So = Total no. of eggs collected where PI = proportion surviving at the intake station PD proportion surviving at the discharge station 4-12

This method accounts for initial and latent effects. To determine if differences in survival proportions between stations and among sampling weeks were statistically significant (a = 0.05), a multi-way contingency analysis was used (Sokal and Rohlf 1969).

4.2.3.1.2 Initial Survival of Larvae and Juveniles Initial survival proportions of larval and juvenile life stages collected at intake and discharge stations were calculated as the ratio of fish found alive and stunned immediately following collection to the total number of fish collected:

No. of live and stunned fish PI or PD = Total no. of fish collected where PI = proportion surviving at the intake station PD.= proportion surviving at the discharge station Stunned fish were grouped with live fish in the analysis to avoid poten-tial bias associated with the subjective stunned category. Differences in survival proportions between intake (control) and discharge stations were determined with the X: test (Sokal and Rohlf 1969).

Data were grouped for statistical comparisons according to sampling station and species. Ichthyoplankton collected at the intake station were pooled by life stage and species for all collections. Discharge station survival proportions were calculated for specific discharge temperature categories. Temperature categories for Atlantic tomcod were:

<26 C and >27 C. Temperature categories for striped bass, white perch, herrings (clupeids), and anchovies (engraulids) were: <29 C, 30-32 C, and >33 C. In 1980, as in 1977-1979, discharge temperatures were measured to the nearest degree C. Thus, these categories correspond exactly with those reported previously as <29.9 C, 30.0-32.9 C, and >33 C (EA 1978a, 1979a, 1981).

4.2.3.1.3 Extended Survival of Larvae and Juveniles Extended survival of larval and juvenile life stages collected at intake and discharge stations was compared to determine if mortality caused by entrainment was manifested beyond the initial survival observation.

For these comparisons survival at each extended survival observation was calculated as a proportion of the initial number of live and stunned fish (i.e., normalized survival), as follows:

SorNo. of fish live or stunned at time i PI or Di Total no. of fish initially alive or stunned 4-13

where PI = normalized survival proportion at time i for fish collected at i the intake PD = normalized survival proportion at time i for fish collected at the discharge Gehan's nonparametric test (Gross and Clark 1975) was used to determine if differences between the intake and discharge normalized extended sur-vival proportions were significant for a particular species and life stage.

4.2.3.2 Entrainment Survival Estimates The calculation of an entrainment survival estimate differed depending on life stage. Entrainment survival estimates for eggs were determined by the ratio of proportions which hatched within 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> for intake'and discharge samples. Larval and juvenile entrainment survival estimates were based on the ratio of initial survival proportions of the intake and discharge stations. Entrainment survival estimates were calculated according to the following assumptions: (1) survival at the intake sta-tion is the conditional probability of surviving sampling, (2) survival at the discharge station is the product of the conditional probabilities of surviving entrainment and sampling, (3) there is no interaction between the two stresses, and (4) each life stage consists of a homogen-eous population in which all organisms have the same probability of surviving to the next life stage.

Entrainment survival was estimated by:

PI Se :PTIx 1O0%

where S = entrainment survival PeD survival proportion at the discharge station PI = survival proportion at the intake station 4.3 RESULTS AND DISCUSSION The 1980 entrainment survival study (30 April - 1.0 July) examined the survival of early life stages of striped bass, white perch, herrings (Clupeidae), anchovies (Engraulidae), and Atlantic tomcod entrained through the Indian Point plant. During the study, Unit 2 and Unit 3 had brief outages. Unit 2 was offline from 3 to 12 June and both units did not operate for short periods during the sampling season (Table 4-1).

Unit 1 did not generate power or operate any circulating pumps during the study. Throughout the study, sampling was conducted at the outflow of discharge port number one (Station DP) using a pumpless plankton sampling 4-14

flume, and at the Unit 3 intake (Station 13) using a rear-draw plankton sampling flume. These floating collection systems were specifically designed to minimize sampling stress on sensitive taxa and life stages.

Survival of ichthyoplankton collected in entrainment samples during the study period was analyzed according to sampling station and discharge temperature. The three discharge temperature categories for which survi-val was determined were: <29 C, 30-32 C, and >33 C. These temperature categories were selected o"i the basis of laboratory and field thermal tolerance studies (EA 1978b and 1978c) and are consistent with tempera-ture categories examined in entrainment survival studies at the Indian Point plant from 1977 to 1978. In addition, survival was analyzed by discharge temperature categories typical of May and June at the Indian Point plant (_<32 C).

Discharge temperatures for May, June, and July in the 1980 entrainment survival study were higher than normal (Figure 4-5) due to above average ambient temperatures and delta-T's. Average discharge temperatures exceeded 30 C in June and 33 C during July. Throughout the sampling season the plant operated generally with fewer than normal circulating pumps, which reduced the volume of cooling water which passed through the cooling system (Table 4-1). A reduction in one circulating water pump can increase the delta-T from I to 5 C depending on the generating load (Tables 3-2 and 3-3). The lower number of circulating pumps in operation during the 1980 sampling season and the relatively lower volume of cool-ing water passing through the plant may have contributed to the high delta-T's and maximum discharge temperatures.

4.3.1 Collection of Ichthyoplankton for Survival Determination The most abundant ichthyoplankton taxon collected at the Indian Point plant during the 1980 entrainment survival study was striped bass (Morone saxatilis) followed in order of decreasing abundance by anchovies (Engraulidae), white perch (Morone americana), and Atlantic tomcod (Microgadus tomcod) (Table 4-3T. These four taxa comprised 96 percent of the ichthyoplankton collected. For the first time since EA began entrainment survival studies at the Indian Point plant (1977), the her-ring family (Clupeidae) was not among the four major taxa collected.

Early season samples were dominated by Atlantic tomcod juveniles (Figure 4-6), which were more abundant in 1980 than in any previous sampling year. A review of conductivity measurements recorded in conjunction with entrainment survival sampling at the Indian Point plant over the 4-year period of 1977 through 1980 showed a distinct relationship between con-ductivity and the occurrence of juvenile Atlantic tomcod during May and early June. During 1978 and 1979 conductivities recorded during sampling were uniformly low (0400 umhos) during May and did not begin to increase until 'the second week of June, reflecting an upstream movement of the salt front. The occurrence of juvenile tomcod in entrainment survival samples was low during both years; only 15 juveniles were collected in 1978 and 10 i-n 1979. In contrast, conductivity levels were relatively high during spring and early summer of 1977 (EA 1978a) and 1980 (Table 4-2), and juvenile tomcod were collected with greater frequency in entrainment survival samples. A total of 62 young-of-the-year Atlantic 4-15

Unit 2 Online 1-- ---

II i I I Unit 3 Online a. J

• m i i

w i

w A

g I

g II I V

• I 1-1-4-I SI I I A

-- - Unit Offline 0 Mean discharge temperature during sampling at Station DP T Range of discharge temperatures 40 during sampling at Station DP Average CL E

20 0 1

5 15 20 25 30 5 10 15 20 25 30 10 APR MAY JUN JUL (a) Source for average daily discharge temperatures was Con Edison 1980.

Figure 4-5. Discharge temperatures at the Indian Point Generating Station during 1980 entrainment sampling season.

TABLE 4-3 TOTAL NUMBER OF EACH ICHTHYOPLANKTON TAXON AND LIFE STAGE COLLECTED FOR SURVIVAL DETERMINATIONS DURING THE ENTRAINMENT SURVIVAL STUDY. INDIAN POINT GENERATING STATION, 30 APRIL - 10 JULY 1980 Taxon Yolk-Sac Post Yolk- Percent of Common Name Scientific Name Eggs Larvae Sac Larvae Juveni I es Total Striped bos5 Morone saxatilis 419 126 349 9 38.3 Anchoviesta) Engraulidae (b) 8 840 0 36.0 White perch Morone americana 0 1 288 3 12.4 Atlantic tomcod Microgadus tomcod 0 0 2 210 9.0 Rainbow smelt Osmerus mordax 0 4 27 5 1.5 Herrings Clupeidae 0 3 26 3 1.4 Si lversides Menidia spp. 0 0 11 0 0.5 American eel Anguilla rostrata 0 0 0 8 0.3 Tessellated darter Etheostoma olmstedi 0 3 4 0 0.3 Yellow perch Perca flavescens 0 5 0 0.2 Winter flounder Pseudopleuronectes americanus 0 0 0 1 0.0 (a) Bay anchovy (Anchoa mitchilli) is the only engraulid occurring to any appreciable extent in the Hudson River estuary..

(b) Survival determinations were not made for anchovy eggs.

Unit 2 Online Unit 3 Online 0.-

C CL 3 E

Eggs, Yolk-Sac Larvae, and Post Yolk-Sac Larvae None Collected I *"

' .. .I. .. I. . I tjl.. . i " 1 .... ... .... I!"-" ?

1l"" 1 " "1 "

70-7 Juveniles L) 60 50 z 40 30 20, 10 APR MAY JUN JUL (a) Source for average daily intake and discharge temperatures was Con Edison 1980.

Figure 4-6. Temporal distribution and thermal exposure of Atlantic tomcod collected at the discharge port station (DP) during the spring-summer entrainment survival study, Indian Point Generating Station, 30 April - 10 July 1980.

tomcod were collected in 1977. In 1980 samples, 209 Atlantic tomcod juveniles and two post yolk-sac larvae were collected. The largest catches were recorded from 5 to 15 May when conductivity levels were low (Figure 4-6). These data suggest that juvenile tomcod were distributed in the proximity of the salt front, and were most subject to entrainment when the salt front moved past the Indian Point plant.

Similar patterns in abundance of striped bass during the sampling season have occurred since 1977. As in previous years, striped bass were first seen in samples as eggs in early May. Peak egg catches occurred between 12 and 21 May (Figure 4-7) when average temperature ranged from 15.1 to 17.1 C (Table 4-2). Yolk-sac larvae were caught from 13 May through 17 June, but never in large numbers. Post yolk-sac larvae were present from 29 May through 9 July, but peak occurrence was from 16 to 19 June.

Juveniles were encountered infrequently from mid-June through the end of the sampling season.

White perch were the next major taxon to appear in entrainment collec-tions (Figure 4-8). Post yolk-sac larvae occurred initally on 27 May but did not become abundant until after mid-June. As in previous years, egg, yolk-sac larvae, and juvenile white perch were seen only infrequently, if at all (Table 4-3).

Anchovies were the second most abundant taxa over the sampling season, but were not collected in large numbers until 23 June (Figure 4-9). Post yolk-sac larvae were the most frequently collected life stage. Eggs were not enumerated and yolk-sac larvae were collected on only one date.. As in previous years, anchovy post yolk-sac larvae occurred during the high salinity periods of late June and early July when water temperatures are also relatively high.

The number of herring collected at the Indian Point plant during 1980 was the lowest of any year since 1977. The low occurrence of herring during the sampling season (Figure 4-10) may be due to their preference for fresh water for spawning and only slightly brackish waters for nursery areas (McFadden 1978, TI 1980). The sampling season in 1980 was preceded by a mild winter and dry conditions in the early spring. With the move-ment of the salt front further upstream than normal during the 1980 sampling season, herring were probably distributed further upstream during the months of April and May and not subject to entrainment at Indian Point.

Consistent with previous entrainment survival studies at the Indian Point plant (EA 1978a, 1979a, 1981), post yolk-sac larvae were collected in larger numbers than other life stages (Table 4-3). Eggs, yolk-sac larvae, and post yolk-sac larvae of striped bass were collected in suffi-cient numbers for entrainment survival determination. Survival analysis for other'taxa was restricted to post yolk-sac larvae, except for Atlantic tomcod juveniles. Entrainment survival was not determined for anchovy eggs because their small size and refractive index make live eggs difficult to detect in water. Weekly length frequency distributions for the major ichthyoplankton taxa collected are presented in Appendix Tables C-i through C-4.

4-19

Unit 2 Online Unit 3 Online II W*

iI II I 6,000 CL 4,000-

,L 0.

4,000 E 0 I- 2,000 50- Eggs 40 30 1

20

-10 Yolk-Sac Larvae 10 qIj -

E z

= 40-Post Yolk-Sac. Larvae 30 20 101 Juveniles 101 Hill,~~~~~~~

HH HI ~ HHII 1111r~~ HHHH H~~fl Il~ ~~~~ ri 30 l3 ll0 5 llJ . 10 l J 15 20 25 25 31 .

31 5 5 1 10 15 15 20 20 251 25 30 5 5 10 1010 APR MAY JUN JUL (a) Source for average daily intake and discharge temperatures was Con Edison 1980.

Figure 4-7. Temporal distribution and thermal exposure of striped bass collected at the discharge port station (DP) during the spring-summer entrainment survival study, Indian Point Generating Station, 30 April - 10 July 1980.

Unit 2 Online Unit -q10nlina I I ii 1... I 6,000

,0.

4,000

• 0.

S 2,000 Eggs

_ __Egs_ None Collected

PI I II' IIlI IIIIIIIII i IlI I1 tII1I~ I I I I II II II II 10 1 Yolk-Sac Larvae 40 Post Yolk-Sac Larvae 30 E.

20 z 10 I'III Juveniles 10

krr1

. .. I . . . I ' I. ..I ' "I.... I .. I ... I "II I'1 "VII "l"l'",111q 30 5 10 15 20 25 31 5 10 15 20 25 30 5 10 APR MAY JUN JUL (a) Source for average daily intake and discharge temperatures was Con Edison 1980.

Figure 4-8. Temporal distribution and thermal exposure of white perch collected at the discharge port station (DPI during the spring-summer entrainment survival study, Indian Point Generating Station, 30 April - 10 July 1980.

Unit 2 Online 6,000

• 4,000 (a

a.

S I- 2,000 Eggs

_ _ _ _ None Analyzed for Survival Yolk-Sac Larvae 10 I"1l it" I t"S "t"IIIl$lI" II 11 . .... II111 100!

Post Yolk-Sac Larvae 90 80 70 C.,

E, 60

.0 50 40 30 20 10.

Juveniles

., ~~None Analyzed for Survival ' .,*

. .. .I. ... i l i !,l

. . . I . . . I. . . I . . . I . . . I. . . . I . . . . I , , l1...

30 5 10 15 20 25 31 .5 10 15 20 25 30 5 10 APR MAY JUN JUL (a) Source for average daily intake and discharge temperatures was Con Edison 1980.

Figure 4-9. Temporal distribution and thermal exposure of anchovies (Engraulidae) collected at the discharge port station (DP) during the spring-summer entrainment survival study, Indian Point Generating Station, 30 April - 1,0 July 1980.

Unit 2 Online 6,000 S.

4,000 CL Cu 3

0:

Eggs None Collected Yolk-Sac Larvae 10 C-5 Post Yolk-Sac Larvae E 10,1 Juveniles

............. i i ii*i iiii None Collected

. ........... i , ]iiii.. ..... I..............

>1 30 5 10 15 20 25 31 5 10 15 20 25 30 5 10 APR MAY JUN JUL (a) Source for average daily intake and discharge temperatures was Con Edison 1980.

Figure 4-10. Temporal distribution and thermal exposure of herrings (Clupeidae) collected at the discharge port station (DP) during the spring-summer entrainment survival study, Indian Point Generating Station, 30 April - 10 July 1980.

Average daily discharge temperatures at the Indian Point plant during the entrainment survival study ranged from 20 to 36 C (Figure 4-5). The majority of ichthyoplankton were collected at discharge temperatures ranging from 21 to 35 C. Based on laboratory thermal tolerance studies, thermal effects of entrainment were expected to be negligible for most ichthyoplankton collected at discharge temperatures less than 30 C (EA 1978b). The percentages of organisms collected at Station DP when dis-charge temperatures equaled or exceeded 30 C were 79 percent for striped bass larvae and 72 percent for white perch larvae. When temperatures at Station DP exceeded 32 C, the percentages of organisms collected were 66 percent for striped bass larvae, 67 percent for white perch larvae, and over 97 percent for anchovy larvae. Only one Atlantic tomcod was collected at Station DP at discharge temperatures above 30 C.

4.3.2 Survival Proportions 4.3.2.1 Survival of Striped Bass Eggs The hatching proportion of striped bass eggs collected at the discharge (Station DP) was 0.469, while the control (Station 13) hatching success was 0.816 (Table 4-4). Intake temperatures associated with the collec-tion of striped bass eggs ranged from 11.8 to 18.4 C and discharge temperatures varied from 23 to 31 C. These discharge temperatures were below those expected to cause significant thermal mortality as determined by thermal laboratory studies. The temperature of the 30-minute TL50 for striped bass eggs 11-49 hours old ranged from 31.5 to 35.2 C (EA 1978b).

Factors influencing the survival of striped bass eggs in 1980 were assessed by using a three-way contingency analysis (Sokal and Rohlf 1969). The three variables examined were survival (Su), station (St),

and sampling week (W) (Table 4-5). Because over 96 percent of all eggs were collected during the weeks of 12 May and 19 May, only data from these two sampling weeks were considered for the analysis. This analysis demonstrated that there was a significant difference (a = 0.05) in survi-val between the intake station and the discharge station (St x Su) which indicates that entrainment did have an effect on striped bass survival.

The fraction of eggs collected at each station was also significantly different between the two weeks (St x W). Fewer eggs were collected at Station DP during the second week than during the first week (53 vs. 93, respectively) thereby giving the survival at the discharge station less weight during the second week. Pooled survival proportions indicated no significant difference in survival by week. However, nonsignificance may be due to sample sizes. The test for interaction among the variables (St x Su x W) was also significant, which indicated that entrainment survival estimates would differ for the two weeks. The significant interaction could be the result of increasing discharge temperatures even though the discharge temperatures were below those expected to cause thermal mortal-ity. Discharge temperatures ranged from 26 to 28 C during the week of 12 May and from 28 to 31 C during the week of 19 May. However, when the survival at the control station (Station 13) is considered, it is evident that there was an almost identical drop in survival for striped bass eggs that had not experienced entrainment (Figure 4-11). This strongly sug-gests that the difference in egg survival over the two week period was caused by factors other than discharge temperatures. Variablity in 4-24

TABLE 4-4 SURVIVAL PROPORTIONS BASED ON HATCHING SUCCESS FOR STRIPED BASS EGGS COLLECTED DURING ENTRAINMENT SURVIVAL SAMPLING, INDIAN POINT GENERATING STATION. 1980 Temperature Number Proportion(a)

Station Range (C) Collected Surviving 13 272 0.816 DP 23-31(b) 147 0.469 (a) Based on the proportion that hatched within 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> following collection.

(b) Entire range of temperatures at which striped bass eggs were collected.

TABLE 4-5 RESULTS OF THREE-WAY CONTINGENCY ANALYSIS FOR INDEPENDENCE AMONG STATIONS (St), SURVIVAL (Su), AND SAMPLING WEEKS (W)

FOR STRIPED BASS EGGS COLLECTED AT THE INTAKE AND DISCHARGE STATIONS DURING ENTRAINMENT SURVIVAL SAMPLING AT THE INDIAN POINT GENERATING STATION, 12-26 MAY 1980 Degree of Hypothesis Tested Freedom G(a) 1 (b)

St x Su indpendence 5 5 .9 3 2 St x W independence 1 7. 3 4 2 (b)

Su x W independence 1 2.546 St x W x Su interaction 1 6.414(b) 72.234(b)

St x W x Su independence 4 (a) Test statistic; critical value is equal toX2 value with appropriate degrees of freedom and a level.

(b) Significant at a = 0.05.

.90 0 Hatching success at control station (13)

(N = 129)

Z Hatching success at experimental station (DP)

(N = 130)

.70 a, 60 Cu 0 6 0

CL

.2 05 00 (N = 93)

(N = 53) 12 MAY 19 MAY Sampling Week(a)

(a) Includes sampling weeks in which ten or more striped bass eggs were collected at either station.

Figure 4-11. Striped bass egg survival by sampling week at the Indian Point Generating Station, 1980.

striped bass egg survival may be the result of egg size, salinity, and the age of the egg (Albrecht 1964; Bayless 1972; Lal et al. 1977). Lauer et al. (1974) found that striped bass eggs 4-18 hours old were more sen-sitive to thermal stress than eggs that were approximately 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> old.

Ecological Analysts, Inc. (1978b) also found that younger eggs had lower 30-minut~e TL5Os than older eggs. A large numiber of striped bass eggs normally die 12 to 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> after spawning as a result of nonfertiliza-tion (Bayless 1972). Any, or all, of these factors could contribute to the weekly differences observed in hatching success.

4.3.2.2 Initial Survival at the Intake Station The initial survival proportions for five major taxa and life stages at the Indian Point Unit 3 intake (Station 13) during 1980 far exceed values obtained at the intake stations during the previous years of 1977-1979 (Table 4-6). Survival proportions for sample sizes of ten or more ranged from 0.323 for anchovy post yolk-sac larvae to 1.000 for juvenile Atlantic tomcod.

The survival proportion for juvenile Atlantic tomcod in 1980 is the first value reported for this life stage at the Indian Point Generating Station. During past study years, late post yolk-sac larvae and juvenile Atlantic tomcod were generally collected infrequently during the entrain-ment sampling season and their entrainment survival was not estimated.

Survival proportions calculated from previous data are 0.500 or lower (Table 4-6).

The uniformly high intake survival for all life stages of striped bass in 1980 illustrates substantial improvement in survival at the intake station(s) when ccompared to previous years. The proportion of eggs that hatched was nearly twice that obtained in 1979, the only other year in which successful hatching occurred after collection. Yolk-sac larvae and post yolk-sac larvae survival was very high, 0.953 and 0.951, respec-tively, which indicates that negligible sampling mortality occurred for these life stages.

White perch post yolk-sac larvae historically have survived collection at intake stations to a lesser extent than striped bass post yolk-sac larvae. This suggests that white perch larvae may be more susceptible to sampling effects than striped bass larvae. However, in 1980 intake sur-vival of white perch post yolk-sac larvae, 0.929, was similar to that of striped bass post yolk-sac larvae.

The high initial survival of the few herring post yolk-sac larvae col-lected (0.889) suggests that collection stress was also low for this species. The highest previous intake survival proportion for herring post yolk-sac larvae was 0.290'in 1977. Such low survival made past entrainment survival estimates for herring questionable.

Anchovies were the only species collected at the intake station that demonstrated a relatively poor ability to survive sampling. Initial survival has improved over the past 3 years (Table 4-6), but this species appears more sensitive to stresses of sampling than the four other taxa examined.

4-28

TABLE4-6 INITIAL SURVIVAL PROPORTIONS FOR ICHTHYOPLANKTON COLLECTED AT THE INTAKES OF THE INDIAN POINT GENERATING STATION, 1977-1980 19 7 7 (b) 19 78 (b) 1979(c) 19 8 0 (d)

Life(a) Proportion Proportion Proportion Proportion Taxa Stage Surviving N Surviving N Surviving N Surviving N Atlantic Late PYSL 0.130 46 0.500 8 0 1.000 25 tomcod and JUV Striped Eggs(e) 0 0.000 62 0.444 124 0.816 272 bass YSL 0.719 32 0.302 63 0.515 66 0.953 85 PYSL 0.610 806 0.447 423 0.500 64 0.951 142 White PYSL 0.563 158 0.344

• perch 180 0.149 195 0.929 113 Herrings YSL 0.290 0 0.152 0 0.000 5 0.000 1 PYSL 100 809 0.232 259 0.889 9 JUV 0.333 3 0.286 14 1.000 1 1.000 2 Anchovies PYSL 0.109 1,254 0.020 500 0.101 457 0.323 260 (a) Only life stages collected during the 1980 study are included for comparison.

(b) Based on pooled data collected at intake Stations 12 and 13 using pump/larval table collection systems.

(c) Based on data collected at intake Station 13 using rear-draw plankton sampling flume with gravity drain-age system.

(d) Based on data collected at intake Station 13 using rear-draw plankton sampling flume with pump drainage system and modifications to evenly distribute water flow across flume diversion screens.

(e) Hatching success data is presented for striped bass eggs.

Note: N = number collected; YSL = yolk-sac larvae; PYSL = post yolk-sac larvae; JUV = juveniles.

The high intake survival proportions obtained at the Indian Point Generating Station in 1980 indicate the success of continued modifica-tions of gear and refinements in minimizing sampling stress on entrainable ichthyoplankton. Survival proportions for Atlantic tomcod, striped bass, white perch, and herring indicate that most ichthyoplankton of these species were alive when entering the sampling gear.

4.3.2.3 Initial Survival at the Discharge Station Survival of juvenile Atlantic tomcod at the discharge station appears to be temperature related. Survival was uniformly high at discharge tem-peratures from 20 to 26 C, ranging from 0.846 to 1.000 (Table 4-7).

However, at discharge temperatures of 27 and 28 C, initial survival was 0.500, and at 34 C the single specimen collected was dead. The consis-tently high survival proportions at discharge temperatures <26 C suggests that thermal stress does not affect entrainment survival at these tem-peratures. However, the reduced survival at temperatures above 26 C is supported by laboratory thermal studies which indicate that the ultimate upper incipient lethal temperature for juvenile Atlantic tomcod during summer ambient water temperature conditions was approximately 27 C (EA 1978b). The ultimate upper incipient lethal temperature is the tempera-ture at which a rapid increase in mortality rate would begin to occur for a species that has fully extended its ability to acclimate to higher temperatures. This parameter is an estimate of the temperature below which no reduction in survival occurs, regardless of exposure time or acclimation temperature (Con Edison 1978).

Initial survival proportions for Atlantic tomcod juveniles at the dis-charge station are also the estimate of entrainment survival because the intake (control) survival was 100 percent (Table 4-7). The entrainment survival estimates for Atlantic tomcod juveniles were 87.7 percent at discharge temperatures <26 C and 48.0 percent at discharge temperatures

>27 C.

The discharge survival proportions obtained in 1980 for Atlantic tomcod are quite similar to the initial survival of the few juveniles collected during 1979. For 1979, discharge survival proportions were 0.833 at temperatures <26 C and 0.500 at temperatures >27 C (Table 4-8). The sampling device used in 1979 was essentially the same as that used in 1980 and, because gear effects were not evident at the discharge station in 1979 (EA 1981), survival should be similar between the two years. Low survival of Atlantic tomcod late post yolk-sac larvae and juveniles during 1977 and 1978 was probably due to damage caused by the pump/larval table collection system. Ebey and Beauchamp (1977) indicated that the probability of a fish being killed by a propeller blade during pump passage is directly proportional to fish length. Although most species of ichthyoplankton collected during entrainment survival sampling are less than 20 mm long, Atlantic tomcod collected during late spring and early summer over the past 4 years ranged from 14 to 62 mm with the majority of specimens between 25 and 40 mm long. The likelihood of Atlantic tomcod incurring damage from pumps is greater than for most ichthyoplankton commonly collected at the Indian Point Generating Station during this time period.

4-30

TABLE 4-7 INITIAL DISCHARGE STATION SURVIVAL (DP Station) AND ENTRAINMENT SURVIVAL ESTIMATES FOR ATLANTIC TOMCOD JUVENILES, AS A FUNCTION OF DISCHARGE WATER TEMPERATURE, INDIAN POINT GENERATING STATION, 1980 Discharge Proportion Temperature (C) N Surviving Se(,)(a) 20 1 1.000 21 22 3 1.000 23 29 0.862 87.7 24 26 0.846 25 72 0.861 26 31 0.935 Thermal Effects

.Expected (b) 27 22 0.500 28 2 0.500 29 30 31 48.0 32 33 34 1 0.000 (a) Because the initial survival proportion at the intake station was 1.000, Se(%) = proportion surviving at the discharge x 100.

(b) Mortalities due to thermal stress are expected at water temperatures greater than 26 C for Atlantic tomcod juveniles, according to laboratory thermal tolerance data (EA 1978b).

N = number collected.

TABLE 4-8 INITIAL SURVIVAL PROPORTIONS FOR ICHTHYOPLANKTON AS A FUNCTION OF DISCHARGE WATER TEMPERATURE, INDIAN POINT GENERATING STATION. 1977-1980 1977 (b) 1 978 (c) 1 9 79 (d) 1980 (e)

Li fe(a) Temperature Proportion Proportion Proportion Proportion Taxa Stage Range (C) Surviving N Surviving N Surviving N Surviving N Atlantic Late PYSL <26 0 0.083 12 0.833 6 0.877 162 tomcod and JUV -I27 0.000 16 0.000 1 0.500 4 0.480 25 Striped Egg(f) Al 1 0 0.000 113 0.327 55 0.469 147 bass YSL <29 0.400 30 0.158 19 0.586 29 0.667 21 30-32 0.333 6 0.030 67 0.750 12 0.562 16

>33 4 0 0.000 11 0 0.500 PYSL (29 0.491 428 0.091 22 0.630 27 0.742 31 30-32 0.440 75 0.282 503 0.701 87 0.812 16

>33 0.467 15 0.038 26 0 0.550 160 JUV (29 1.000 1 0 0 1.000 2 30-32 1.000 2 0.625 8 0 0

>33 0.000 3 0.500 2 0 0.429 7 (a) Only life stages collected during the 1980 study are included for comparison.

(b) Based on pooled data collected at discharge Stations D3 and DP using pump/larval table collection systems.

(c) Based on pooled data collected at discharge Stations D1, D3, and DP using pump/larval table collection systems.

(d) Based on data collected at discharge Station DP (discharge port outfall) using pumpless plankton sampling flume with gravity drainage system.

(e) Based on data collected at discharge Station DP (discharge port outfall) using pumpless plankton sampling flume with pump drainage system and modifications to evenly distribute water flow across the flume diversion screens.

(f) Hatching success data are presented for striped bass eggs.

Note: N = number collected; YSL = yolk-sac larvae; PYSL = post yolk-sac larvae; JUV = juveniles.

.TABLE 4-8 (CONT.)

19 77 (b) 19 79 (d) (e) 1 9 78 (c) 19 8 0 Li fe( a) Temperature Proportion Proportion Proportion Proportion Taxa Stage Range (C) Surviving N Surviving N Surviving N Surviving N White YSL <29 0 0.000 I 0.000 1 0 perch 30-32 0.000 2 0.000 1 0.000 9 0

>33 0 0.000 1 0 0.000 1 0.320 PYSL <29 36732 0.359 39 0.000 22 50 0.898 49 13 r)3 0.318 22 0.245 163 0.289 97 0.556 9

>33 0.333 6 0.000 11 0 0.496 117 JUV <29 0 0 1.000 2 1.000 1 30-32 1.000 2 1.000 3 0 0

>33 1.000 3 0 0 1.000 2 Herrings YSL <29 0 0 0 0.000 1 30-32 0 0 0 0

>33 0 0 0 0 PYSL <29 0.149 47 0.035 142 0.305 151 0.615 13 360C32 0.000 13 0.023 398 0.222 36 0.500 4

>33 0.000 5 0.018 57 0 0 Anchovies YSL <29 0 0 0 0 30-32 0 0 0 0

>33 0.000 3 0.000 2 0 0.000 8 PYSL <29 0 0.000 4 0.070 172 0.040 24 30-32 0.039 233 0.000 25 0.028 107 0

>33 0.028 471 0.000 382 0.063 206 0.016 556

When high salinity conditions bring entrainable-sized tomcod juveniles into the vicinity of the Indian Point plant, the majority are likely to be entrained at discharge temperatures <26 C (Table 4-8), and entrainment survival should approach 90 percent. Growth of juvenile tomcod through-out the spring reduces their susceptibility to entrainment during high discharge temperature conditions (>27 C).

Initial survival proportions for striped bass larvae collected at Station DP in 1980 were, with one exception, the highest values yet achieved (Table 4-8). Survival of yolk-sac larvae ranged from 0.667 at tempera-tures <29 C to 0.500 at temperatures >33 C. Post yolk-sac larval survi4al was highest at 30 to 32 C (07812) and lowest at >33 C (0.550).

The survival proportions for larvae collected at high temperatures are particularly important since they were based on far greater sample sizes (164 larvae) than in any previous year (EA 1978a, 1979a, and 1981).

The increase in survival proportions in 1980 was even more striking for white perch than for striped bass. Survival proportions for post yolk-sac larvae ranged from 0.898 at <29 C to 0.496 at temperatures >33 C (Table 4-8). At the high temperature range, survival was above-all previous survival values at any temperature category. The substantial improvement in survival demonstrates the value of minimizing sampling stress in entrainment survival programs.

Initial survival proportions of herring post yolk-sac larvae increased in 1980 from estimates obtained in previous years for the same temperature categories (Table 4-8). As indicated in Section 4.3.1, the number of herrings collected in 1980 was considerably less than in earlier studies and this low sample size may reduce precision of the survival propor-tions. However, improved survival of other taxa in 1980 suggests that the improvement in survival proportions for herrings is probably real.

Anchovies were the only taxa collected in 1980 that did not show a dramatic improvement in the initial proportion surviving at Station DP (Table 4-8). At discharge temperatures <29 C the proportion of post yolk-sac larvae surviving in 1980 was 0.040 compared to 0.070 in 1979.

Most anchovies were collected at temperatures >33 C. At those higher discharge temperatures, the initial survival p*oportion of post yolk-sac larvae at the discharge station was 0.016. In 1977 and 1979, when slightly higher survival proportions were obtained, most of the larvae were collected at temperatures of 33 and 34 C. In 1980 only 17 percent of the anchovy post yolk-sac larvae were collected at these relatively lower temperatures (Table 4-9). Most of the anchovies collected in the temperature range >33 C were collected at temperatures >35 C, and there-fore experienced greater thermal stress than those collected previously.

4.3.3 Extended Survival Proportions Normalized extended survival proportions were compared for organisms col-lected at the intake (Station 13) and discharge (Station DP) to determine whether latent effects caused by entrainment were present. To increase the sample size for initial statistical testing, data were pooled across 4-34

TABLE 4-9 INITIAL SURVIVAL FOR ANCHOVY POST YOLK-SAC LARVAE COLLECTED AT DISCHARGE TEMPERATURES >33 C AT THE INDIAN POINT GENERATING'STATION, 1977-1980 19 77 (a) (b) 19 79 (c) 198 0 (d)

Discharge 19 7 8 Proportion Ne Temperature Proportion (e) Proportion (e) Proportion (e)

(C) Surviving __e) Surviving ___e _ Surviving N(e)

Surviving Ne) 33 .0.036 165 (35.0%) 0.000 25 (6.5%) 0.214 14 (6.8%) 0.000 28 (5.0%)

34 0.022 275 (58.4%) 0.000 37 (9.7%) 0.041 98 (47.6%) 0.045 66 (11.9%)

35 0.000 31 (6.6%) 0.000 279 (73.0%) 0.119 42 (20.4%) 0.014 362 (65.1%)

36 -- __ (0.0%) 0.000 41 (10.7%) 0.000 52 (25.2%) o.010 100 (18.0%)

Total 0.028 471 0.000 382 0.063 206 0.016 556 tb)

(a) c)

Based on pooled data collected at discharge Stations 03 and DP using pimp/larval table collection systems.

Based on pooled data collected at discharge Stations DI and DP using pump/larval table collection systems.

Based on data collected at discharge Station DP (discharge port outfall) using pumpless plankton sampling flume with gravity drainage system.

(d) Based on data collected at discharge Station DP (discharge port'outfall) using pumpless plankton sampling flume with pump drainage system and modifications to evenly distribute water flow across the flume diversion screens.

(e) Numbers in parentheses represent the percentage of the total number of post yolk-sac larvae collected at discharge temperatures >33 C that were collected at each of the designated temperatures.

Note: N = number collected.

all collection temperatures for each station. Gehan's nonparametric test (Gross and Clark 1975) was used to examine the null hypothesis that the survival distributions are the same at both stations.

Extended survival through the 96-hour observation period was higher than in previous years. Normalized survival proportions at 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> for striped bass were about 60 percent for yolk-sac larvae and greater than 70 percent for post yolk-sac larvae (Table 4-10). Survival proportions for white perch post yolk-sac larvae were similar to those for striped bass. Survival of Atlantic tomcod juveniles was also high, 80 percent at Station 13 and 56 percent at Station DP. Herrings and anchovies also exhibited high extended survival compared to previous years, although values for these taxa were lower than for the striped bass, white perch, and tomcod. Herring 96-hour survival was 0.375 at Station 13 and 0.600 at Station DP. However, these proportions were based on very small samples. For anchovies, post yolk-sac larvae survival was 0.048 at Station 13 and 0.0 at Station DP.

Only Atlantic tomcod exhibited significantly different (a = 0.05) survi-val patterns between intake and discharge stations (Table 4-10). When juvenile tomcod collected at Station DP were separated into two groups based on collection temperature, both groups exhibited poorer survival than fish collected at Station 13 (Figure 4-12). Juveniles collected at

<26 C sustained 28 percent mortality through 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Survival after 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> was relatively stable. At temperatures >27 C survival declined rapidly to 58 percent after 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and by the end of the 96-hour observation period survival was only 20 perent. However, survival pro-portions for this group were based on only 12 fish initially alive.

The similarity of survival distributions between organisms collected at intake and discharge stations for most taxa indicates that latent effects of entrainment are minimal and that entrainment survival can be estimated adequately from initial survival proportions. The only exception appears to be Atlantic tomcod juveniles; extended survival was significantly lower at the discharge station than for control (Station 13) fish. This could be due to the larger size of juvenile tomcod (from 14 to 60 mm) compared to larvae of other taxa (5 to 15 mm), which may subject them to more physical damage during passage through the power plant. These physical stresses may not be severe enough to cause immediate death, but may instead cause mortality within 24 to 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.

4.3.4 Entrainment Survival Estimates 4.3.4.1 Atlantic Tomcod Juveniles Entrainment survival estimates for Atlantic tomcod juveniles, based on initial survival proportions, require no adjustment for sampling mortal-ity since all tomcod captured at Station 13 were initially alive.

Entrainment survival thus was 87.7 percent at discharge temperatures <26 C and 48.0 percent at temperatures >27 C (Table 4-11). However, as demonstrated in Section 4.3.3, signTficant differences in extended survi-val existed between fish captured at intake and discharge stations.

Therefore, survival proportions at some other time interval may be preferrable for calculating entrainment survival rates. If survival 4-36

TABLE 4-10 NORMALIZED EXTENDED SURVIVAL PROPORTIONS FOR ICHTHYOPLANKTON COLLECTED DURING ENTRAINMENT SURVIVAL SAMPLING, INDIAN POINT GENERATING STATION, 1980 Survival Proportions Initial Time After Collection (Hours) z(a)

Taxa Life Stage Station No. Alive 3 6 12 24 48 72 96 Striped YSL 13 81 1.000 0.963 0.926 0.815 0.728 0.679 0.580 -0.42 bass DP 25 0.960 0.880 0.800 0.720 0.680 0.600 0.600 PYSL 13 135 0.978 0.941 0.941 0.911 0.911 0.837 0.748 -0.62 DP 124 0.944 0.911 0.879 0.879 0.863 0.839 0.718 White PYSL 13 105 0.981 0.943 0.914 0.886 0.857 0.771 0.619 1.37 perch DP 107 0.953 0.944 0.888 0.879 0.869 0.804 0.729 Herrings PYSL 13 8 0.625 0.625 0.625 0.500 0.500 0.375 0.375 .1.10 DP 10 1.000 1.000 0.700 0.600 0.600 0.600 0.600 Anchovies PYSL 13 84 0.417 0.202 0.095 0.071 0.060 0.060 0.048 -1.70 DP 10 0.100 0.100 0.100 0.100 0.100 0.000 --

Atlantic Late PYSL(b) 13 25 1.000 1.000 0.960 0.960 0.960 0.920 0.800 tomcod and JUV DP 154 0.968 0.896 0.812 0.714 0.662 0.604 0.558 (a) Test statistic for differences in survival distributions based on Gehan's nonparametric test (Gross and Clark 1975).

(b) Two late post yolk-sac Atlantic tomcod larvae were included in the normalized extended survival at Station 13.

(c) Indicates significance at a=0.05 under the null hypothesis that the survival distributions are similar.

Critical value of Z is IZI > 1.96.

Note: YSL = yolk-sac larvae; PYSL = post yolk-sac larvae; JUV = juveniles.

0.8' 13 0.7' 0.6' DP (20-26 C)

.2 0~

CL 0.6' U) 0.4 DP (>27 C) 3 6 12 24 96 Time after Collection (hours)

Figure 4-12. Extended survival of Atlantic tomcod juveniles collected at Station 13 and at Station DP at discharge temperatures <26 C and >27 C. Indian Point Generating Station, 1980.

TABLE 4-11 ENTRAINMENT SURVIVAL ESTIMATES (Se) FOR DOMINANT ICHTHYOPLANKTON COLLECTED AT THE INDIAN POINT GENERATING STATION. 1980 Discharge X2 (d)

Taxa(a) Life Stage Nd ( b) Se(%)(C) P Temperature Range (C)

Atlantic tomcod Late PYSL <26 162 87.7 (66.2) (e? 3.456 >o.05o(f) and JUV -27

-24_31 (g) 25 48.0 (29.2) e 17.568 <0.001 Striped bass Eggs 147 57.5 54.076 <0.001 YSL <29 21 70.0 14.839 30-32 16 59.0 21.151 <0.001 PYSL <29 31 78.0 14.005 <0.001 30-32 16 85.4 4.633 <0. 050

>33 160 57.8 62.536 <0.001

>0.050(f)

White perch PYSL <29 49 96.7 0.452 T33 117 53.4 69.2(g) 52. 319 >0.050(f)

Herrings PYSL <29 13 2.006 <0.005 Anchovies PYSL -?29 24 12.4 8.297

33 556 5.0 165.227 <0.001 (a) Includes all taxa and life stages for which sample sizes were >10 for at least one discharge temperature category.

b* Number collected at the discharge station (Station DP) at the indicated temperature range.

Se' Iwere calculated for temperature categories for which sample sizes were >10, at the intake (over all temperatures) and discharge stations, except where indicated.

(d) The null hypothesis (H.) tested by X2 is that discharge survival is equal to survival of organisms at the intake (a =0.05).

(e) Numbers in parentheses represent S (%) based on proportions surviving 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from collection.

This alternative Se (%) is presented because of a significant difference between intake and discharge extended-survival proportions for Atlantic tomcod.

(f) Indicates acceptance of Ho, which is that the survival of organisms collected at the discharge was not significantly lower than that of those collected at the intake (a = 0.05). The critical X2 value is 3.84.

(g) Only nine herring post yolk-sac larvae were collected at the intake station, but because of the importance of this taxa, the Se is presented.

Note: YSL = yolk-sac larvae; PYSL = post yolk-sac larvae; JUV = juveniles.

proportions through 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after collection are used as the basis for S, estimates, entrainment survival for Atlantic tomcod would be 66.2 p rcent at temperatures <26 C and 29.2 percent at >27 C.

4.3.4.2 Striped Bass Entrainment survival for striped bass eggs collected during the 1980 study was 57.5 percent (Table 4-11). The gear effects ratio for artifi-cially spawned striped bass eggs was 0.959 from collection system calibration data (Section 5) indicating that the intake sampling gear' appears to be slightly more stressful than the discharge gear for eggs.

The small deviation from unity indicates that bias due to differences in sampling stress was minimal and no adjustment to the entrainment survival estimate was made.

Intake (control) survival of striped bass larvae was uniformly high in 1980 (Table 4-6), so the Se estimates closely reflect discharge survival (Table 4-8). Entrainment survival for yolk-sac larvae was lower than for post yolk-sac larvae for two temperature categories in which comparisons were possible (Table 4-11) confirming results obtained by Lauer et al.

(1974) which indicated that younger striped bass larvae were more suscep-tible than older larvae to stresses encountered during entrainment. The majority of striped bass post yolk-sac larvae were collected at discharge temperatures >33 C. Since the mean TL50 (based on 30-minute exposures) for striped b'ass larvae was 33 C (EA 1978b) the survival of larvae col-lected in this temperature range, 57.8 percent, is at least as high as that which would be expected if larvae had been exposed only to thermal stress. This fact, along with the high S estimates for the lower tem-perature ranges, suggests that entrainment mortality of post yolk-sac larvae is caused primarily by thermal stress and that synergistic effect's between mechanical and thermal stress, if they occur at all, are small.

4.3.4.3 White Perch Discharge temperatures had an even greater effect on entrainment survival for white perch post yolk-sac larvae than for striped bass. At discharge temperatures for which no thermal effects would be expected, <29 C (EA 1978b), the S estimate was 96.7 percent (Table 4-11). in fact, the reduction in qurvival at the discharge station was not statistically significant at a = 0.05. However, entrainment survival for white perch post yolk-sac larvae collected at discharge temperatures >33 C was 53.4 percent, similar to the value obtained for the congeneric striped bass at the same temperatures. The extreme difference in Se estimates between the two disc harge temperature ranges again suggests that mechanical stress during entrainment has only a small effect on white perch and striped bass larvae.

4.3.4.4 Herrings Entrainment survival for herring post yolk-sac larvae was high (69.2 percent) at temperatures (29 C. However, herrings appear slightly more susceptible to mechanical stress than the white perch and striped bass because thermal stress should not occur at temperatures (29 C. The sur-vival of herring at the discharge station was not significantly lower 4-40

(a = 0.05) than that at the intake station (Table 4-11), although small sample size may have prevented the detection of an actual difference in survival.

4.3.4.5 Anchovies Anchovies survive the entrainment experience less frequently than any of the other major taxa studied. The relatively low Se estimates for this species, regardless of temperature, suggest that thermal effects were not the major contributor to their low entrainment survival. Anchovies are highly vulnerable to mechanical stress, as indicated by the low survival at Station 13 (Table 4-6). This extreme sensitivity to physical stress makes it difficult to precisely estimate entrainment survival for this species, although it must certainly be low when compared to the other taxa.

4.3.4.6 Comparison of*1980 Entrainment Survival Data With 1977.

1978, and 1979 Results Plant operational mode was atypical during the 1980 entrainment survival sampling season. In contrast to previous years, maximum, or nearly maxi-mum, cooling water flow was not maintained for the Indian Point Generating Station during May, June, and July of 1980 when striped bass, white perch, herrings, and anchovies were entrained. At least two circu-lating pumps, one pump each for Units 2 and 3, were not operating during most of the 1980 entrainment sampling season (Table 4-1). In addition, the discharge flow was not supplemented by the Unit 1 circulating water pumps as it was in the past. The reduced cooling flow increased magni-tude of delta-Ts which allowed discharge temperatures to rise above 33 C during the period of peak occurrence for larvae of important species (Figure 4-5). Discharge temperatures recorded during the entrainment season in 1980 were generally higher than during all previous study years (1977-1979).,

Discharge temperatures at the Indian Point plant do not normally exceed 33 C during periods of high ichthyoplankton abundance, with the exception of anchovy larvae. This is confirmed by the maximum discharge tempera-ture profile for the Indian Point plant (Figure 4-5), determined by adding the calculated maximum delta-T to the seasonal plot of maximum ambient temperatures (Con Edison 1978). The maximum discharge tempera-ture profile indicates that temperatures above 33 C should occur only in mid-summer (mid-July to mid-August) after the primary period of abundance of entrainable fish life stages. I!chthyoplankton of striped bass, white perch, and most other species would usually be exposed to discharge temperatures below 33 C during early summer if maximum cooling water flow is maintained.

The uniqueness of the 1980 data is highlighted by the fact that the majority of striped bass and white perch post yolk-sac larvae (77 and 67 percent, respectively) were collected at discharge temperatures of >33 C.

In previous years the percentage of post yolk-sac larvae collected at temperatures >33 C has ranged from 0 to 5 percent for striped bass and from 0 to 9 percent for white perch (Table 4-12). Atlantic tomcod late post yolk-sac larvae and juveniles, striped bass eggs and yolk-sac 4-41

TABLE 4-12 TOTAL NUMBER OF IMPORTANT ICHTHYOPLANKTON SPECIES COLLECTED AT DISCHARGE STATIONS OF THE INDIAN POINT GENERATING STATION DURING SPRING-SUMMER ENTRAINMENT SURVIVAL SAMPLING, 1977-1980 Discharqe Temp. Cateqory Life(a) <33 C >33 C Taxa Stage Year N  % N Total Atl antic Late PYSL 1977 15 93.8 1 6.2 16 tomcod and JUV 1978 13 100.0 0 0.0 13 1979 10 100.0 0 0.0 10 1980 186 99.5 1 0.5 187 Stri ped EGG 1977 0 0 0 bass 1978 113 100.0 0 0.0 113 1979 55 100.0 0 0.0 55 1980 147 100.0 0 0.0 147 YSL 1977 36 100.0 0 0.0 36 1978 86 88.7 11 11.3 97 1979 41 100.0 0 0.0 41 1980 37 90.2 4 9.8 41 PYSL 1977 503 97.1 15 2.9 518 1978 525 95.3 26 4.7 551 1979 114 100.0 0 0.0 114 1980 47 22.7 160 77.3 207 PYSL 61 91.0 6 9.0 67 White 1977 perch 1978 185 94.0 11 5.6 196 1979 147 100.0 0 0.0 147 1980 58 33.1 117 66.9 175 Herrings PYSL 1977 60 92.3 5 7.7 65 1978 540 90.5 57 9.5 597 1979 187 100.0 0 0.0 187 1980 17 100.0 0 0.0 17 Anchovies PYSL 1977 233 33.1 471 66.9 704 1978 29 7.1 382 92.9 411 1979 279 57.5 206 42.5 485 1980 24 4.1 556 95.9 580 (a) Includes all life stages for which Se's were calculated in 1980.

Note: N = number collected.

Survival sampling during each year was conducted over the follow-ing sampling periods:

1977: 1 June to 18 July 1978: 1 May to 12 July 1979: 30 April to 14 August 1980: 30 April to 10 July

larvae, and herring larvae occur predominantly before discharge tempera-tures exceed 33 C, even during an atypical year such as 1980. Anchovy larvae are the only major taxa frequently collected at discharge temperatures >33 C and a greater percentage, 96 percent, were collected at this high temperature range in 1980 than in any previous year.

The occurrence of discharge temperatures >33 C during primary abundance periods for entrainable life stages of spring and summer spawning species has important consequences for entrainment survival. Based on laboratory thermal effects studies for larval Hudson River fishes, temperatures >33 are within the critical range at which thermally induced mortality would be expected (EA 1978b). Mean TL50s (temperature lethal to 50 percent of the test organisms) determined for important taxa were 32.4-33.3 C for alewife, 33.5 C for blueback herring, 33.1 C for American shad, 33.4 C for bay anchovy, and 33.0 C for striped bass. Upper incipient lethal temperatures, the temperatures at which increased mortality occurs regardless of acclimation temperature, were 33.5 C for striped bass post yolk-sac larvae and 33.8 C for early juvenile white perch. Thus, for most species of interest in the Hudson River, temperatures typically found during their period of abundance in entrainment samples should not represent extreme thermal hazards. However, if temperatures are allowed to exceed 33 C, substantial mortality due to thermal stress would be expected.

To aid in comparing 1980 results to previous years, discharge temperature categories were combined to produce S estimates representative of typi-cal conditions (<_32 C) and atypical c~nditions (>33 C). The 1980 entrainment survival values for temperatures <32 C exceeded previous estimates obtained for all species commonly found in the vicinity of the Indian Point Generating Station, ,except for striped bass eggs and anchovy post yolk-sac larvae (Table 4-13). Survival for striped bass eggs at the intake and discharge stations was higher in 1980 than in 1979, but the relative improvement in survival at the intake station was greater than at the discharge, resulting in the lower S estimate. Survival of striped bass eggs is variable and may be r~lated to such factors as the age (EA 1978a) and size of the egg (Albrecht 1964). The lower Se for anchovy post yolk-sac larvae in 1980 compared to 1977 appears to be due to the lower survival at the intake in 1977, when compared to 1980 (Table 4-6), rather than a difference in survival at the discharge station (Table 4-8).

Entrainment survival estimates in 1980 at discharge temperatures >33 C exceeded the only previous value for white perch post yolk-sac larvae, but were below values obtained previously for striped bass and anchovy post yolk-sac larvae. The higher value for striped bass post yolk-sac larvae in 1977, however, was based on a much smaller sample, 15 versus 160, than in 1980. The majority of anchovies collected during 1977 and 1979 were collected at discharge temperatures of 33-34 C, while the majority of anchovies were collected at discharge temperatures of 35-36 C in 1980 (Table 4-9). The 1980 S estimates represent the most reliable values obtained to date for the high temperature range. The high intake 4-43

TABLE 4-13 ENTRAINMENT SURVIVAL ESTIMATES (Se) FOR ICHTHYOPLANKTON OCCURRING AT AND ABOVE TYPICAL SUMMER DISCHARGE EXPOSURE CONDITIONS, INDIAN POINT GENERATING STATION. 1977-1980 Survival Se%) at Typical(a) May-July Survival (Se%) at High(a)

Discharge Temp. Conditions (<32 C) Discharge Temp. Conditions (>33 C3 Taxa (b) Life Stage 1977 (c) 19 78 (d) 1979 (e) 1980if}

19 7 7 (c) 19 7 8 (d) 19 7 9 (e) 1 9af) 80 Atlantic Late PYSL 0.0 -- 70.0 82.8 tomcod and JUV Striped Egg -- 0.0 73.6 57.5 bass YSL 54.1 19.2 63.4 65.3 0.0 PYSL 79.2 61.3 68.4 80.5 76.6 8.5 -- 57.8 White PYSL 61. 62.8 29.9 91.0 -- 0.0 -- 53.4 perch Herrings PYSL 40.3 17.1 28.9 66 . 1 (9) -- 11.8 Anchovies PYSL 35.8 0.0 5.4 12.4 25.7 0.0 6.3 5.0 (a) S 's were calculated for temperature categories for which sample sizes were >10, except where indi-cited.

(b) Includes all taxa and life stages for which Se's were calculated in 1980.

(c) Entrainment survival estimates (S ) based on pooled data collected at Stations 12, 13. D3, and DP using pump/larval table collection systpcss.

(d) Entrainment survival estimates (S ) based on pooled data collected at Stations 12, 13, DI, D3, and DP using pump/larval table collection systems.

(e) Due to the higher gear effect determined for the rear-draw (intake) plankton sampling flume.than for the pumpless (discharge) plankton sampling flume in 1979, the survival percentages for larvae collected during this year are based on the initial survival proportions at Station DP (discharge port outfall) multiplied by 100. That Is, these survival values are unadjusted for intake (control mortality).

(f) Entrainment survival estimates (S ) baled on samples collected at Station 13 using the rear-draw plank-ton sampling flume, and at Statiofl DP (discharge port outfall) using the pumpless plankton sampling flume. In contrast to 1979, both flume samplers were equipped with pump, as opposed to gravity drain-age systems, as well as modifications to evenly distribute water flow across the flume diversion screens.

(g) Only nine herring post yolk-sac larvae were collected at the intake station in 1980, but because of the importance of this taxa, the Se Is presented.

Note: YSL = yolk-sac larvae; PYSL = post yolk-sac larvae, JUV = juveniles.

Dash (--) indicates insufficient sample size for Se calculations.

station survival, which reduces the likelihood of any bias in the S estimate (see Section 4.4), and the large sample sizes, particularly for striped bass and white perch post yolk-sac larvae, allow a great deal of confidence in these estimates.

4.3.5 Entrainment Survival as a Function of Size As larval fish grow, their natural mortality rate generally declines (Farris 1960, Dahlberg 1979). This decline occurs partly because larger larvae are available as prey for fewer predators. Large larvae can also ingest larger zooplankton as food, deriving more energy per plankter and increasing possible food items. Avoidance capabilities increase with size, further reducing vulnerability to predation. Physiological changes also occur which increase their ability to withstand extremes of tempera-ture, salinity, dissolved oxygen, or physical stress (Lauer et al. 1974).

The change in population size with changing length has been modeled mathematically by Hackney and Webb (1978):

dN ZN dL. GL where dN = change in population size dL = change in length Z = instantaneous mortality rate G = instantaneous growth rate N = population size L = length The rate of change of the population size, dN/N, with changing length is an inverse function of length:

dN/= Z This model and similar length-related models of mortality have been used to describe early life stage population dynamics for crappie, Pomoxis sp.

(.Hackney and Webb 1978); Pacific sardine, Sardinops caerulea (Farris 1960); Atlantic mackerel, Scomber scombrus (Sette 1943); winter flounder, Pseudopleuronectes americanus (Pearcy 1962); and striped bass, Morone saxatilis (TI 1980).

The relationship between size and mortality rate indicates that as a fish grows the probability that it will live to reproduce increases rapidly.

Loss of small larvae at power plants therefore results in a smaller reduction in the population than losing the same number of larger larvae or juveniles. However, Se estimates (Section 4.3.4) are calculated under 4-45

the assumption that each life stage consists of a homogeneous population in which all organisms have the same fixed probability of surviving to the next life stage. Violation of this assumption can lead to over-estimates or underestimates of'entrainment survival, depending on the size distribution of the entrained larvae.

The errors caused by violating the assumption of a homogeneous population can be eliminated by calculating entrainment mortality as a function of size. The relationship between entrainment survival and size was esti-mated by separating all larvae collected and measured into 2-mm size intervals. The initial survival proportions within each interval were calculated for Station 13 and for Station DP at discharge temperatures

<32 C and >33 C. Only striped bass and white perch had sufficient numbers coTlected and/or initial survival high enough to permit analysis.

Length specific S estimates were calculated according to standard analytical procedures (Section 4.2). Curves were fitted to the Se esti-mates by inspection.

Initial survival proportions at the intake station increased rapidly with increasing size for both striped bass and white perch (Figures 4-13 and 4-14). Both species' initial survival was 1.0 for the 6-7 mm size inter-val. Striped bass survival dropped slightly between 10 and 13 mm, but white perch survival remained at 1.0 for all larger size groups.

Survival at the discharge station generally increased with increasing size, although larvae collected at temperatures >33 C exhibited rela-tively lower survival for a given size than larvae collected at <32 C (Figures 4-13 and 4-14). Large striped bass larvae (-10 mm) had lower survival than smaller larvae for striped bass and white perch larvae at the higher temperature range.

Estimates of entrainment survival for each length interval generally increased with size and were very similar for striped bass and white perch (Figure 4-15). Striped bass S estimates ranged from 47 percent to 111 percent at the low temperature rAnge, <32 C. White perch estimated entrainment survival at <32 C ranged from 67 percent to 119 percent. At discharge temperatures of <32 C most larvae larger than 10 mm survive entrainment. This size corresponds to that at which sampling mortality became undetectable in 1979 (EA 1980a) and 1980 (Chapter 5). At the high temperature range, >33 C, entrainment survival did not consistently increase with increasing size (Figure 4-15). This may be due to the tendency for larger larvae to occur later in the season when discharge temperatures are higher. The rate of survival declines rapidly at expo-sure temperatures above 33 C (EA 1978a) and the survival of any larvae would be very sensitive to the actual discharge temperature encountered.

These analyses of 1980 entrainment survival at the Indian Point Generating Station demonstrate that entrainment survival varies with size for striped bass and white perch larvae. For both species very high survival is expected for larvae larger than 10 mm, if discharge tempera-tures are maintained below 33 C. At higher discharge temperatures, the 4-46

1.00-

.90" DP (<32 C)

.80"

.70" 0.

.60 a-CL

(>33 C)

Z 0-i

.50-4-F

.40 -

.30 -

20 I1 I I-I 1 1 4.5 6.5 8.5 10.5 12.5 14.5 16.5 18.5 Midpoint of Length Interval Figure 4-13. Initial survival as a function of size for striped bass larvae at the Indian Point Generating Station, 1980.

1.007 DP (<32 C)

.90 -

.80 -

.70- DP (>33 C) 0 0

a-

0. .60 -

cn 0(U

.50-C*

.40-

.30-

.20-

.10-I I II I I 1 1 1 I 4.5 6.5 8.5 10.5 12.5 14.5 16.5 18.5 Midpoint of Length Interval Figure 4-14. Initial survival as a function of size for white perch larvae at the Indian Point Generating Station, 1980.

Se Estimates (16) 120- o Striped bass at <32 C 0

• White perch at <32 C Striped, bass at >33 C (27)

White perch at >33,C 0 Total number of fish in Se estimate 110, (59) 100 - - - - - -4, at temperature < 32 C (39).

90- 0 0 (22) (10)

(84) 0 (631 4) 80- (41)

U1 70-C:

(83) (131) Se at temperature > 33 C E 60-I(54 (15)

C wi 5o0- (19), (87)

(56) 40-30-fig I I 1 I g 1

.I 6.5 8.55 10.5 12.5 14.5 16.5 18.5 4.5 Midpoint of Length Interval Note: Se curves fitted by inspection Figure 4-15. Estimates of initial entrainment survival as a function of size for white perch and striped bass larvae at the Indian Point Generating Station, 1980.

actual temperature and size of larvae must be considered to predict entrainment survival. Analysis of entrainment survival by length and estimates of size-related natural mortality can provide increased accu-racy in predicting conditional entrainment mortality rates.

4.4 IMPLICATIONS OF THE 1980 ENTRAINMENT SURVIVAL RESULTS ON POTENTIAL BIASES TO ENTRAINMENT SURVIVAL ESTIMATES The high intake survival obtained through application of gear refinements at the Indian Point plant in 1980 (Table 4-6) indicates that most larvae, with the possible exception of anchovies, were alive when they entered the sampling gear. This provides new insight on factors which may affect positive or negative biases in entrainment survival estimates (Boreman and Goodyear 1980). The degree to which sampling stress was minimized in 1980 and the resultant high intake (control) survival observed for nearly all species and life stages examined is a strong indication of the con-servative nature of the survival estimates presented in Tables 4-7, 4-11, and 4-13. High intake survival proportions would cause either a true estimate or an underestimate of entrainment survival. Greater select-ivity of the intake sampling gear for dead organisms, which could cause an overestimation of entrainment survival, clearly did not occur.

High intake survival could reflect either the actual proportions of live and dead organisms at the intake station, i.e., a true predominance of live organisms or gear selectivity for live organisms. This latter situ-ation could be caused by either of the following factors: dead organisms are so fragile that most are destroyed during sampling, or dead organisms are stratified in the water column at the intake and rarely occur at the depth of sample withdrawal.(3.4 m below the surface). If dead organisms are being damaged beyond recognition by the pumpl ess p1lankton sampl ing flume at the intake station, then it is reasonable to expect that the greater physical stresses associated with entrainment would also destroy dead organisms when they enter the cooling water system and preclude their identification and enumeration in discharge samples. This would nul 'lify any bias in survival between the two sampling stations. Alterna-tively, if dead organisms are stratified and do not generally occur at the depth of sample withdrawal, then underestimation of entrainment survival should occur because the proportion surviving at the intake station would be inflated. Dead organisms which are stratified at the intake station would be expected to be more evenly distributed within the discharge water due to the mixing of water within the canal system, and be more susceptible to collection in the discharge sampling gear.

A remaining assumption which could affect bias in the entrainment survi-val estimates is that a significant number of organisms which enter the cooling system alive are damaged beyond recognition during the entrain-ment process, thus preventing their identification and enumeration in discharge samples. This would cause an overestimate of entrainment survival. Physical stresses to entrained organisms may result from a number of factors, including stresses associated with pump passage (cavi-tation, turbulence, contact with impeller blades), mechanical abrasion in the pipes, abrupt pressure changes, and shear forces. Based on the results of tests conducted in simulated power plant condensers, various investigators have concluded that typical power plant condensers cause 4-50

minimal mechanical damage (<5 percent mortality) to larvae of most species (Coutant and Kedl 1975; Marcy et al. 1978; O'Connor and Poje 1979). Circulating water pumps were suggested as the most likely source of physical damage to entrained organisms. However, recent power plant simulator studies conducted at the Oak Ridge National Laboratories (ORNL) refute this supposition (Cada et al. 1980). The ORNL power plant simula-tor was designed to reproduce the internal hydraulics of an open-cycle condenser cooling water system. In addition to imposing thermal, pressure, and fluid-induced shear stresses typical of power plant conden-sers, it included a pump selected for its similarity to circulating water pumps used at power plants. The results discounted previous speculation that substantial mutilation or destruction of live organisms occurs in the circulating water pumps. Therefore, it is unlikely that an overesti-mate of entrainment survival would occur due to physical damage from entrai nment.

The uniformly high intake survival for Atlantic tomcod juveniles, striped bass eggs, and striped bass, white perch, and herring larvae obtained at the Indian Point Generating Station in 1980, and the recent power plant simulation studies (Cada et al. 1980), give credibility to the current entrainment survival estimates. The 1980 entrainment survival data, therefore, provide valid estimates of entrainment survival which are conservative because they are likely to underestimate true entrainment survival.

4-51

5. ENTRAINMENT SAMPLING GEAR CALIBRATION STUDY

5.1 INTRODUCTION

Survival estimates for ichthyoplankton entrained through the cooling water system of the Indian Point Generating Station are calculated from the proportions of organisms that survive collection at the intake (con-trol) and discharge (experimental).sampling stations (Section 4.2.3.2).

A critical assumption is that mortality due to sampling stress is identi-cal for the intake and discharge collection systems. This study was designed to examine that assumption by estimating survival of organisms collected in the rear-draw plankton sampling flume used at the Unit 3 intake (Station 13) and the pumpless plankton sampling flume used at the discharge port (Station DP) during the 1980 entrainment survival study.

Hatchery-reared striped bass were used in these experiments to allow greater control of factors which might affect susceptibility to sampling stress (e.g., organism age and size).

Contrary to expectations, larval survival at the Indian Point Generating Station in 1979 was often greater at the discharge station than at the intake station. In such cases, estimates of entrainment survival that corrected for intake control survival were not possible. This difference in gear effects was confirmed for hatchery-reared yolk-sac and early post yolk-sac striped bass larvae used in the flume calibration study con-ducted during the 1979 sampling season at Indian Point (EA 1981). To eliminate the difference in sampling stress, changes were made in the design and operation of the sampling:flumes used in the 1980 sampling season. The sampling flumes were modified to distribute water flow evenly across the surface of the vertical diversion screens and to stan-dardize flume drain rates. Flow diffusion panels (baffles) and slotted outlet standpipes were installed behind the vertical screens to eliminate areas of localized high velocity flow that could cause organisms to become impinged on the diversion screens. Identical pump drainage systems were installed to permit control and standardization of the drain rates.

5.2 METHODS 5.2.1 Field and Laboratory Procedures Collection system calibration tests used striped bass eggs and larvae obtained from the Con Edison hatchery facility at Verplanck, New York.

After arrival from the hatchery, eggs were supplied with air and larvae were supplied with a slow flow of oxygen. Larvae were acclimated with ambient Hudson River water for a minimum of two hours; eggs were not acclimated. Experiments were conducted by releasing approximately 100 striped bass eggs or larvae into each sampling flume and collecting them at the end of a 15-minute sampling period. Four tests were conducted at each flume with eggs, yolk-sac larvae, early post yolk-sac larvae, and late post yolk-sac larvae.

Gear operating procedures during the collection system calibration tests were the same as those for entrainment survival sampling (Section 4.2.1),

5-1

except that organisms were introduced just above the inlets of the sampling flumes. Introduction of eggs and larvae in the first five tests was simultaneous with the start of sampling. For all tests after 27 May, larvae were introduced 30 seconds before each test to avoid the concen-tration of organisms in the turbulent water at the sample inlet. After retrieving the test organisms from the flume, the number of recovered live and dead striped bass was determined to assess initial survival.

All stripedbass ichthyoplankton recovered alive were maintained at the onsite laboratory for up to 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> to assess extended survival. The proportion of striped bass eggs surviving to hatch (up to 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> after collection) was used as the basis for egg survival.

Controls were conducted with each experimental release to assess the effects of handling and increased water temperatures in the discharge canal on the eggs and larvae. At the beginning of each calibration test, approximately 100 eggs or larvae were placed in transportation containers filled with ambient water from the intake flume (13 handling control),

ambient water from the discharge flume (DP handling control), and dis-charge water at the discharge flume (DP thermal control). Control organisms remained in these containers during the 15-minute test period and the period of flume drainage., They were then transported with the experimental fish to the onsite laboratory at the end of the calibration test. Approximately 100 eggs or larvae were placed directly in appro-priate holding containers filled with ambient water (hatchery control) to assess the general health of each batch of hatchery-reared ichthyoplank-ton, the effects of transportation from the hatchery to the Indian Point site, and the effects of minimal handling. Survival of control organisms was determined immediately after testing and was monitored for up to 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> in the same manner as experimental organisms.

5.2.2 Analytical Procedures Analyses were designed to detect differences in initial and extended sur-vival proportions for hatchery-reared striped bass collected in the rear-draw and pumpless plankton sampling flumes. This information was used to estimate the magnitude of gear-induced mortality for the two sampling gear.

5.2.2.1 Survival Proportions The survival of striped bass eggs released into the sampling flumes was determined by the proportion of eggs that hatched within 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br />. This procedure is consistent with that used for wild eggs (Section 4.2.3.1).

Hatching success is calculated as follows:

Pl or PD Number of eggs that hatched within 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> So = Total number of eggs recovered where, P = proportion surviving at the intake (Station 13)

P0 = proportion surviving at the discharge (Station DP) 5-2

An egg is considered viable only if it survives to hatch. Within the 96-hour observation period, all the eggs-collected should either hatch or die.

For yolk-sac and post yolk-sac larvae, the initial proportion of organ-isnms surviving collection in the sampling gear was determined as:

No. of alive and stunned fish observed immediately after collection PI or PD= Total number of fish recovered Extended survival data were examined to determine if mortality occurred beyond the initial survival observation and to detect differences between the experimental and control test data. Survival was normalized by cal-culating survival proportions for each extended survival observation on the basis of the initial number of live and stunned fish. Gehan's non-parametric test (Gross and Clark 1975) was used to detect differences in the survival distributions for the entire extended survival observation period.

5.2.2.2 Determination of Gear Effects To isolate gear effects at each station, the mortality caused by handling and thermal effects was factored out of the egg hatching success and larval initial survival-proportions according to the following equations.

Initial survival proportions at each of the stations can be considered estimates of the product of the probabilities of surviving the stresses encountered by the organisms at each'station, if it is assumed that there is no interaction, or synergism, between the stresses. Thus, PI = (P[h] P[gi]) (1) and P = (P[h] . Pi . Plgd]) (2) where P[h] = probability of surviving handling stress P[t] = probability of surviving thermal stress P[gi] = probability of surviving gear induced stress at the intake flume P[gd] = probability of surviving gear induced stress at the discharge flume Additionally, P[h] and P[h] . P[t] can be estimated-directly from the handling and thermal controls at the intake and discharge stations.

Ph = PEEl] (3).

5-3

and Ph

• Pt = (P[h] : P[t]) (4) where Ph = proportion of organisms that survive handling Ph

• Pt = proportion of organisms that survive handling and thermal stress Equations (1)-(4) can be combined algebraically to produce estimates of P[t], P[g.], and P gd] and to test whether the stresses were statisti-cally sig ificant.

Ph _'Pt (P[h] . P[t] A (5)

Ph P[h]

P1 (P[h] : P[gi]) (6)

Ph P[h] P P~gil(6)

SPD _ (P[h] . Pit] . P~gd]) Pl-dL (

Ph

• Pt (P[h] . Pit])

Thermal and gear effects, once isolated as in Equations,(5), (6), and (7), were tested for significance using a chi-square (xx) test (Sokal and Rohlf 1969). The ratio of gear effects served as an indicator of the similarity or difference of sampling stresses between the rear-draw (intake) and pumpless (discharge) flume systems. If sampling stresses for the two gear are approximately equal for a given life stage, the ratio P[g ]/P[g,] will approach unity. However, if sampling stress is greater ij the gear-draw flume (Station 13), the ratio will be less than 1; conversely, if sampling stress is greater in the pumpless flume (Station DP), the ratio will be greater than 1.

5.3 RESULTS 5.3.1 Initial Survival The flume calibration tests for striped bass eggs indicated generally good hatching success from both sampling gear and their controls. The first test using striped bass eggs had relatively lower hatching success, which varied from 0.743 for the intake station handling control to 0.523 for the eggs collected at Station DP (Table 5-1). Handling stress may have contributed to this low hatching success. Hatching success for both handling controls was relatively low, which suggests that handling stress may have affected the survival of the experimental and thermal control organisms. It is also possible that the hatchery eggs were not in good condition, since the hatching success was 0.535 for striped bass eggs in the hatchery control that were subjected to only minimal handling. Age 5-4

TABLE 5-1 HATCHING SUCCESS AND INITIAL SURVIVAL PROPORTIONS FOR HATCHERY-REARED STRIPED BASS EGGS AND LARVAE FROM THE FLUME CALIBRATION STUDY AT THE INDIAN POINT GENERATING STATION, 1980 Age(a) Temp. Number of PPhInitial Survival h't Proportions PI pD Life Stage Date (days) Station (C) Organisms PH Ph Ph.t PI D Egg(b) 12 MAY 1 H 16.0 99 0.535 13-HC 15.0 70 0.743 DP-HC 15.0 73 0.575 DP-TC 28.0 69 0.594 13 15.0 86 0.593 DP 28.0 65 0.523 (a) Age of eggs is from day of spawning; age of larvae is from day of hatching.

(b) Hatchingsuccess at 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> after collection is presented for eggs.

Note: H denotes "hatchery control;" HC denotes "handling control;" TC denotes "thermal control."

Survival propo rtions for eggs -No. of eggs that hatched within 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> Total no. of eggs recovered Survival proportions for larvae =

No. of alive + stunned larvae observed immediately after collection or testing Total no. of larvae recovered P = proportion of organisms surviving from the hatchery h= proportion of organisms surviving handling stress Pt.= proportion of organisms surviving thenmal stress associated with sampling P[gi] = probability of surviving stress of the sampling gear at Station 13 PEgd I= probability of surviving stress of the sampling gear at Station DP

TABLE 5-1 (CONT.)

Initial Survival Proportions Age(a) Temp. Number of PH Ph Ph" Pt P 1 P 0 Life Stage Date (days) Stati on Organisms Egg (cont.) 13 MAY 2 H 16.0 97 0.990 13-HC 15.0 102 0.980 DP-HC 16.0 92 0.989 DP-TC 27.0 107 0.981 13 15.2 84 0.845 DP 27.0 93 0.957 19 MAY 3 H 17.0 79 0.987 13-HC 17.0 110 1.000 DP-HC 15.0 60 1.000 DP-TC 25.0 150 0.993 13 16.8 95 0.979 OP 24.0 81 0.938 22 MAY I H 17.0 66 0.985 13-HC 19.0 109 0.991 DP-HC 18.0 105 0.990 DP-TC 31.0 77 0.961 13 19.0 107 0.981 DP 31.0 63 1.000 Yolk-sac 27 MAY 4 H 18.0 95 1.000 Iarvae 13-HC 19.0 97 0.887 DP-HC 20.0 97 0.918 DP-TC 31.0 92 0.880 13 18.9 92 0.978 DP 31.0 79 0.101

TABLE 5-1 (CONT.)

Initial Survival Proportions Age(a) Temp. Number of Life Stage Date (days) Station P_H Ph PhPt P I PD (C) Organisms Yolk-sac 28 MAY 4 H 18.0 94 1.000 I arvae 13-HC 19.0 95 0.674 (cont.) DP-HC 19.0 104 0.644 DP-TC 32.0 95 0.884 13 17.8 104 0.798 DP 32.0 89 0.607 2 JUN 7 H 21.0 97 1.000 13-HC 20.0 100 0.980 DP-HC 20.0 97 1.000 DP-TC 31.0 67 0.985 13 19.4 93 1.000 DP 31.0 89 0.944 5 JUN 10 H 21.0 101 1.000 13-HC 21.0 100 1.000 DP-HC 21.0 100 1.000 DP-TC 28.0 97 0.990 13 20.8 100 0.990 DP 28.0 100 1.000 Post yolk- 9 JUN 23 H 20.0 100 1.000 sac larvae 13-HC 22.0 100 0.990 DP-HC 22.0 102 1.000 DP-TC 31.0 95 1.000 13 20.4 94 1.000 DP 31.0 98 1.000

TABLE 5-1 (CONT.)

Initial Survival Proportions Age (a) Temp. Number of PH Ph Ph'Pt PI PD Life Stage Date (days) Station _() Organisms Post yolk- 10 JUN 24 H 18.0 100 1.000 sac larvae 13-HC 20.0 101 1.000 (cont.) DP-HC 20.0 97 1.000 DP-TC 30.0 100 1.000 13 20.4 100 0.990 DP 30.0 99 0.929 16 JUN 30 H 20.0 1.000 13-HC 21.0 102 0.980 DP-HC 21.0 100 1.000 DP-TC 32.0 98 0.990 13 21.6 100 0.990 DP 33.0 99 0.990 17 JUN 31 H 21.0 100 1.000 I3-HC 22.0 99 0.970 DP-HC 22.0 99 1.000 DP-TC 32.0 98 1.000 13 22.0 98 0.980 DP 33.0 98 0.980 23 JUN 37 H 22.0 100 1.000 13-HC 24.0 100 1.000 DP-HC 24.0 100 1.000 DP-TC 34.0 100 1.000 13 24.2 99 1.000 DP 34.0 100 0.950

TABLE 5-1 (CONT.)

Initial Survival Proportions Age(a) Temp. Number of P_H Ph Ph'Pt PI PD Life Stage Date (days) Stati on (C) Organisms Post yolk- 24 JUN 38 H 23.0 100 1.000 sac larvae 13-HC 24.0 100 1.000 (cont.) DP-HC 24.0 100 1.000 DP-TC 34.0 100 0.970 13 23.6 100 1.000 DP 34.0 99 0.919 30 JUN 44 H 24.0 100 1.000 13-HC 24.0 99 0.990 DP-HC 24.0 100 1.000 DP-TC 28.0 99 1.000 13 23.8 101 0.990 DP 30.0 100 1.000 1 JUL 45 H 24.0 100 1.000 13-HC 24.0 100 1.000 DP-HC 24.0 100 0.990 DP-TC 35.0 99 0.960 13 24.3 98 1.000 OP 36.0 99 0.949

of the eggs did not seem to be a major factor in the lower hatching suc-cess. Similarly aged eggs used as hatchery controls in the fourth test exhibited good hatching success (0.985). However, eggs are known to be very sensitive to stress within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of spawning (Lauer et al. 1974).

The hatching success of eggs tested at Station DP ranged from 0.938 to 1.000, and for eggs sampled at Station 13 the range of hatching success was 0.845-0.981, excluding 12 May. Hatching success when pooled over all four tests was 0.860 for eggs collected at Station 13 and 0.868 at Sta-tion OP (Table 5-2). Pooled hatching success showed statistically significant gear effects at the intake and discharge stations. Differ-ences in survival between the discharge handling and thermal controls were not statistically significant, indicating that temperature alone did not reduce survival at Station DP. The gear-effect ratio for striped bass eggs was 0.959, indicating that gear stress was slightly greater at the intake than the discharge station.

Four flume calibration tests were completed using hatchery-reared striped bass yolk-sac larvae. Two circumstances affected the recovery and survi-val of the fish collected in the pumpless plankton sampling flume at Station OP. A break in the seal between the vertical screens and the flume bottom was discovered and corrected on 2 June after the flume cali-bration test; the break may have affected the recovery of test organisms.

The next test, on 5 June 1980, recovered 100 yolk-sac larvae as opposed to 79-89 yolk-sac larvae previously collected at Station DP (Table 5-1).

Use of only one primary water outlet to moderate the flume water depth at Station OP on 27 May also may have affected the results. During sample collection the use of only one outlet would have increased the probabi-lity of contact of larvae with the vertical screen associated with the open outlet because of the greater water flow through that screen.

Increased contact with the vertical screens may have been the cause of the very low survival of yolk-sac larvae (0.101) obtained from Station OP on 27 May 1980 (Table 5-1). The problem was corrected immediately and subsequent survival of striped bass yolk-sac larvae at Station OP increased markedly to 0.607 or greater.

The survival proportions of striped bass yolk-sac larvae generally improved with age and length for the tests on 28 May, 2 June, and 5 dune.

The survival for 4-day old larvae was 0.798 at Station 13 and increased for 10-day old larvae-to 0.990 (Table 5-1). At Station DP, survival improved from 0.607 to 1.000 for 4- and 10-day old larvae, respectively.

The pooled survival proportions for the yolk-sac larvae were 0.926 at Station 13 and 0.856 at Station OP (Table 5-2). 'These survival values for yolk-sac larvae at both experimental stations are very high compared to results from the 1979 sampling season (EA 1981). However, the ratio of gear effects indicates that for striped bass yolk-sac larvae the gear at the discharge had a greater effect on survival than the gear at Sta-tion 13 (Table 5-2). The effect of the gear at Station OP and the effect of temperature (as measured by the thermal control) on survival were statistically significant (a = 0.05). The significant difference in survival between the discharge handling control and thermal control was contrary to expectations; survival was greater for the thermal control larvae than for the handling control larvae. The cause of the signifi-cant gear effects was expected to be a reduction in survival associated 5-10

TABLE 5-2 POOLED INITIAL SURVIVAL PROPORTIONS AND ESTIMATES OF SAMPLING GEAR EFFECTS FOR HATCHERY-REARED STRIPED BASS EGGS AND LARVAE FROM THE FLUME CALIBRATION STUDY AT INDIAN POINT GENERATING STATION, 1980 Initial Estimated Probabilities Gear Effect Survival Proportions Of Survival Ratio Age(a) Temp. Number of PhP P P 2 Ptg1 ]/P[g3 Organisms h ht 1 0 P t Pg 11 Pgd X (b)

Life Stage (days) Station (C)

Eggs(c) 1-3 I3-NC 15-19 391 0.946 DP-HC 15-18 330 0.900 DP-TC 25-31 403 0.916 1.018 0.534 13 15-19 372 0.909 16.32* 0.959 0.860 DP 24-31 302 0.868 0.948 4.248*

Yolk-sac 4-10 13-HC 19-21 295 0.888 Iarvae(d) DP-IIC 19-21 301 0.877 DP-TC 28-32 259 0,950 1.083 9.056*

13 17.8-20.8 297 0.926 1.043 2.508 DP 28-32 278 0.856 0.901 13.231* 1.158 Al I post 23-45 13-HC 20-24 801 0.991 yolk-sac DP-HC 20-24 798 0.999 larvae DP-TC 28-35 789 0.982 0.983 11.524*

13 20.4-24.3 790 0.995 1.004 0.783 1.021 DP 30-36 792 0.965 0.983 4.740*

(a) Age of eggs is from day of spawning; age of larvae is from day of hatchingw (b) Null hypotheses tested for each life stage are P(t] = 1, P[gi] - 1, and P~gd] = 1. X2 values were obtained by comparing the proportions in columns denoted by Ph and Ph'Pt, Ph and P1 . and Ph'Pt and P0 for the appropriate stations for the three null hypotheses. Rejection of a null hypothesis at a = 0.05 is signified by *, and at a - 0.01 by *

(c) Hatching success data is presented for striped bass eggs.

d Data from 28 May, 2 June, and 5 June are pooled for this analysis.

e) Due to the low number of deaths, probabilities of rejecting a true null hypothesis were also computed with Fisher's exact test (Sokal and Rohlf 1969) for these groups. The exact probabilities associated with these tests were 0.1196 for early post yolk-sac larvae and 0.00003 for late post yolk-sac larvae.

Note: HC denotes "handling control;" TC denotes "thermal control."

No. of eggs that hatched within 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> Survival proportions for eggs = Total no. of eggs recovered Survival proportions for larvae = No. of alive + stunned larvae observed immediately Total no. of larvae recoveredafter collection or testing P, = proportion of organisms surviving handling stress Pt = proportion of organisms survival thermal stress associated with sampling P[g 1 J = probability of surviving stress of the sampling gear at Station 13 P d] = probability of surviving stress of the sanpling gear at Station DP.

TABLE 5-2 (CONT.)

Initial Estimated Probabilities Gear Effect Survival Proportions of Survival Ratio Age(a) Number of P h Ph11,Pt PI PD Pit] Pg19] P[gd] X2(b) P[gi]/P[9]

Temp. Organisms Life StaLe da-3) Station 20-C) 402 0.985 Early post 23-3 1 13-NC 20-22 DP-HC 20-22 398 1.000 yolk-sac 391 larvae DP-TC 30-32 0.990 0.990 4.092%en 0.937 13 20.4-22.0 392 0.992 1.007 0.985 2.572 1.022 31-33 394 DP 0.975 24 399 0.997 Late post 37-45 13-HC 400 0.998 yolk-sac DP-NC 24 7.512-.(e)

DP-TC 28-35 398 0.975 0.977 0.000 larvae 23. 6-24.3 398 1.000 1.021 13 0.997 0.979 2.369 DP 30-36 398 0.955

with increased temperatures, but in this case, temperature appears to have had an opposite effect.

The initial survival proportions for all of the flume calibration tests using striped bass post yolk-sac larvae were consistently high. For the eight sampling dates the survival of striped bass post yolk-sac larvae at Station 13 varied from 0.980 to 1.000 (Table 5-1). For larvae collected at Station DP survival was also high, ranging from 0.919 to 1.000. The pooled survival data for all post yolk-sac larvae from 23 to 45 days old indicated that, in spite of the very high survival at both stations, a gear effect is present at Station DP (significant at a = 0.05). However, the effect was so small (P[g I = 0.983) that when the fish were separated by age into groups of early ý23-31 days old) and late (37-45 days old) post/yolk-sac larvae, the gear effect was not statistically significant (Table 5-2). The gear-effect ratios for the two age groups were similar, 1.022 (early) and 1.021 (late), which indicated slightly greater effects of the puipless plankton sampling flume at Station DP. The thermal effect was also statistically significant (a = 0.05) for all post yolk-sac larvae combined and late post yolk-sac larvae, which indicated that discharge water temperatures as high as 35 C were responsible for mor-tality above that due to handling alone (Table 5-2), but temperatures up to 32 C did not significantly affect survival.

These gear effects for post yolk-sac larvae may be real, as determined by statistical tests, but they are quite small and possibly negligible for survival proportions based on smaller sample sizes (e.g., entrainment survival samples). Since the gear effect ratio is only slightly greater than unity (1.02), and entrainment survival samples are too small to dis-tinguish survival differences of 2 percent, the bias to entrainment survival estimates (Section 4.3.4) is negligible.

Survival of hatchery-reared striped bass larvae varied with length at Station DP, but not at Station 13 (Figure 5-1). Regardless of length, the survival of fish in the intake station handling control, intake station experimental group, and the thermal control at Station DP was above 90 percent, except for 6-mm larvae (Table 5-3). The estimated probability of surviving the sampling stress at Station 13 (P[gi]) was 0.998, or greater, as a result of the very high survival of the intake control and experimental larvae (Table 5-3). The high survival of fish in the thermal (DP) control group indicated that temperature and handling stresses combined were not directly size-selective for striped bass lar-vae. For those larvae collected in the pumpless plankton sampling flume at Station UlP, however, length had a noticeable effect on survival--as length increased, survival increased (Figure 5-1). For larvae less than 10 mm, the high gear-effect ratios indicate the greater effect of the sampling flume at Station DP than at Station 13. The effects of both sampling flumes on larvae longer than 10 mm appear to be very small (Table 5-3 and Figure 5-1).

The probability of surviving sampling stress for the smaller larvae (5-7 mm) at Station DP decreased as the discharge temperature increased (Table 5-4). The temperature and handling stresses to which the thermal control organisms were subjected had only a slight effect on survival (Table 5-3). Interaction or synergism of sampling, thermal, and handling 5-13

2 1.8 1INTAKE DISCHARGE 6-"*GEAR EFFECTS Ri C3w WLUL U- 1.4 w

E-0 rwo 0 1.2 o......

u-I* w1 I_ C>"A" Lw C:% -o S ** S e,6, 0.6 0.4 I 2 4 6 8 10 12 14 16 Ja8 12 TOTAL LENGTH(MM)

Figure 5-1. Intake and discharge station gear effects on the survival of hatchery-reared striped bass larvae as.a function of length (mm) at the Indian Point Generating Station, 1980.

TABLE 5-3 INITIAL SURVIVAL AND ESTIMATED GEAR EFFECTS BY LENGTH CATEGORIES FOR HATCHERY-REARED STRIPED BASS LARVAE FROM THE FLUME CALIBRATION STUDY AT THE INDIAN POINT GENERATING STATION. 1 9 8 0 (a)

Rear-Draw Plankton Sampling Flume Pumpless Plankton Sampling Flum*e Intake Station 13 Discharqe Station DP Gear-Effect Total Length Control Experimental Control Experimental Ratio n Ph'P~gi] PLgi] n Ph'Pt P gd] rrl/d (mm) n Ph n Ph* Pt"P- d 4.0 16 1.000 7 1.000 1.000 0 0 5.0 22 0.909 32 0.938 1.032 34, 0.941 18 0.722 0.767 1.346 6.0 87 0.724 101 0.842 1.163 107 0.897 98 0.796 0.887 1.311 7.0 26 0.962 19 1.000 1.040 14 1.000 26 0.885 0.885 1.175 8.0 9 1.000 0 4 1.000 0 9.0 30 0.967 11 1.000 1.034 29 1.000 18 0.833 0.833 1.241 10.0 100 1.000 62 1.000 1.000 105 0.990 77 0.935 0.944 1.059 11.0 167 0.982 169 0.982 1.000 139 0.971 182 0.962 0.991 1.009 12.0 155 0.994 130 0.992 0.998 139 0.993 127 0.929 0.936 1.066 13.0 61 1.000 74 1.000 1.000 89 0.978 80 0.975 0.997 1.003 14.0 33 1.000 43 1.000 1.000 37 0.973 40 0.975 1.002 0.998 15.0 6 1.000 24 1.000 1.000 11 1.000 13 1.000 1.000 1.000 16.0 1 1.000 6 1.000 1.000 3 1.000 1 1.000 1.000 1.000 17.0 1 1.000 3 1.000 1.000 0 0 18.0 .0 1 1.000 0 0 (a) Data from 27 May 1980 are excluded.

Note: n = number of organisms Ph = proportion of organisms surviving handling stress Pt= proportion of organisms surviving thermal stress associated with sampling at Station DP P[gi] = probability of surviving stress of the sampling gear at Station 13 P[gd] = probability of surviving stress of the sampling gear at Station DP.

TABLE 5-4 INITIAL SURVIVAL AND GEAR EFFECTS BY LENGTH FOR STRIPED BASS LARVAE AT THE INDIAN POINT GENERATING STATION, 1980 Gear-Effect Temp. at Survival Gear Effects Ratio Length Station DP P[gi ]/P[gd]

(am) Date Station n Ps P[gi] P[gd]

(c) 5 28 MAY HC- 13 21 0.905 1.582 13 31 0.936 1.034 DP-TC 29 0.966 DP 32.0 17 0.632 0.654 6 28 MAY HC-13 60 0.617 1.448 13 63 0.698 1.131 DP-TC 75 0.867 DP 32.0 62 0.677 0.781 2 JUN HC-13 17 0.941 1.063 13 29 1.000 1.063 DP-TC 28 1.000 DP 31.0 23 1.000 1.000 5 JUN HC-13 10 1.000 13 9 1.000 1.000 0.933 DP-TC 14 0.933 DP 28.0 13 1.000 1.072 Note: n = number of organisms Ps = proportion surviving P[gi] = probability of organisms surviving the sampling gear stress at Station 13 P[gd] = probability of organisms surviving the sampling gear stress at Station DP HC = handling control TC = thermal control

TABLE 5-4 (CONT.)

Gear-Effect Temp. at Survival Gear Effects Ratio Length Station DP (mm) Date Station (C) n Ps P1gi] P[gd]

P[gi]/P 1 gd]

7 2 JUN HC-13 11 0.909 1.467 13 3 1.000 1.100 DP-TC 10 1.000 DP 31.0 9 0.750 0.750 5 JUN HC-13 15 1.000 1.000 13 3 1.000 1.000 DP-TC 14 1.000 DP 28.0 14 1.000 1.000

stresses may contribute to the discharge gear effects on survival of 5-7 mm larvae. These lengths correspond to the yolk-sac developmental stage, which is recognized as a more sensitive stage than older and larger larvae (Lauer et al. 1974 and EA 1978b). Possible synergism was also noticed for wild yolk-sac larvae (Section 4.4). The changes in the gear-effect ratio with discharge temperature are magnified in some cases because the intake station handling control survival was below that of the intake station experimental fish. However, the direct relation of discharge temperature to gear stress on survival still exists.

5.3.2 Extended Survival The extended survival of yolk-sac larvae was very high at Stations 13 and DP.. Normalized survival remained above 75 percent for both stations throughout the 96-hour observation period (Table 5-5). The survival distributions for yolk-sac larvae were not significantly different (a = 0.05) for the two stations.

Survival of early post yolk-sac larvae collected at Station DP was slightlty greater than at Station 13 for most of the extended survival observation period; however, these differences were not significant at a = 0.05 (Table 5-5). Normalized survival of early post yolk-sac larvae remained near, or was greater than, 80 percent through the 72-hour observation, but decreased to 0.550 for Station 13 and 0.589 for Station DP by 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br />. This sudden decline in survival after 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> at both stations may be the result of starvation as the remaining energy reserves are depleted and no food is available. Feeding has been demonstrated to be critical to the survival of striped bass larvae at this stage of development (Lewis and Heidinger 1981; Bonn et al. 1976).

The survival of late post yolk-sac larvae at the intake station was slightly greater than at the discharge station at most of the extended survival observations (Table 5-5). These differences were not signifi-cant at a = 0.05. Despite normalized survival greater than 95 percent at both stations through 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, late post yolk-sac larvae survival declined to less than 10 percent by 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> (Table 5-5). Since food requirements are greater for late, post yolk-sac larvae than for early post yolk-sac larvae, the effects of starvation may occur earlier and cause the rapid decline in survival, especially at 72 and 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br />.

5.4 DISCUSSION The flume calibration study has shown that differences in survival between the intake and discharge station sampl ing gear are minimal.

A gear-effect ratio of 1.0 would indicate that gear stresses are identi-cal. In 1980 these ratios were all within 4 percent of 1.0 except for yolk-sac larvae. Of the life stages studied, striped bass post yolk-sac larvae were least affected by gear stress. The sampling gear at Station 13 was'slightly more stressful for striped bass eggs than gear at Station DP. In contrast, the gear-related stress on yolk-sac larvae was greater at Station DP.

Alterations in the design and operation of the sampling flumes to reduce stress on organisms were successful as shown by the reduction in gear 5-18

TABLE 5-5 NORMALIZED EXTENDED SURVIVAL FOR HATCHERY-REARED STRIPED BASS YOLK-SAC AND POST YOLK-SAC LARVAE TESTED DURING THE COLLECTION SYSTEM CALIBRATION STUDY. INDIAN POINT GENERATING STATION. 1980 Survival Proportions Initial Time After Collection (Hours)

Life Stage Station No. Live *3 6 12 24 48 .72 96 Yolk-sac 13 275 0.938 0.891 0.851 0.818 0.793 0.767 0.764 -0.50 1arvae DP 238 0.895 0.832 0.815 0.794 0.790 0.782 0.756 Early post 13 389 0.995 0.995 0.990 0.959 0.884 0.779 0.550 -1.18 yolk-sac larvae DP 384 1.000 1.000 0.990 0.969 0.922 0.797 0.589 Late post 13 397 *0.995 0.995 0.992 0.967 0.763 0.398 0.081 -1.67 yolk-sac larvae DP 380 0.995 0.984 0.979 0.953 0.758 0.326 0.055 (a) Test statistic for differences in survival distributions based on Gehan's nonparametric test (Gross and Clark 1975). Critical value for Z is IZI > 1.96. m = 0.05 under the null hypothesis that the survival distributions are similar.

effects and improvements in gear-effect ratios from 1979 to 1980.

Hatching success for eggs was high for both years, but the gear effects (sampling mortality) were further reduced in 1980. In 1980 the rear-draw sampling flume at Station 13 had a greater adverse effect on hatching success (P[g 1/P gd1 = 0.959), while in 1979 the gear at Station DP was more stressful. Initial survival of striped bass yolk-sac larvae improved substantially in 1980 and the stresses from both sampling flumes were reduced. The gear-effect ratio improved from 0.438 in 1979 to 1.158 in 1980. A small effect on survival of yolk-sac larvae still occurs due to sampling-associated stress at Station DP. Striped bass post yolk-sac larvae had very high initial survival in 1979 and 1980, and the differ-ences between gear effects decreased in 1980 for the groups of all post yolk-sac larvae and early post yolk-sac larvae, so that the gear-effect ratio for the life stage improved from 0.929 to 1.021.

Extended survival observations revealed no significant effects of sampling gear on the survival of yolk-sac and early post yolk-sac striped bass larvae. However, late post yolk-sac larvae had poorer extended sur-vival than either yolk-sac or early post yolk-sac larvae. The greater food requirements of older larvae may have caused starvation, since larvae were not fed throughout the observation period, which resulted in mortality in the last 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />. Similar results have been observed at other generating stations on the Hudson River (EA 1979d).

Analysis of larval survival and gear effects by length revealed that, for larvae less than 10 mm, survival at Station DP and the associated gear effectwas related to length. This relation between length and survival was not found for larvae greater than 10 mm or for fish in control and Station 13 groups. Data for larvae from 5 to 7 mm suggested that the lower survival at Station DP may be due to an interaction between han-dling, thermal, and sampling stresses. Interaction between factors has been previously suggested from power plant simulation studies (Cada et al. 1980; Schubel et al. 1979), and was also noted for wild yolk-sac larvae in 1980 field studies (Section 4.4).

Sampling biases need to be minimized to accurately estimate entrainment survival. The bias of gear effects was statistically significant, but small,Ifor striped bass eggs at Station 13, yolk-sac larvae at Station DP, and post yolk-sac larvae at Station DP. These gear effects, measured using large sample sizes, were so small that the biases may not be detectable for the smaller sample sizes obtained with standard entrain-ment survival sampling efforts. The gear-effect ratios greater than unity for striped bass larvae indicate that for this life stage any bias caused by the sampling gear would make corresponding entrainment survival estimates conservative when determined by sampling wild larvae (Section 4.4.1).

5-20

REFERENCES Albrecht, A.B. 1964. Some observations on factors associated with survival of striped bass eggs and larvae. Calif. Fish and Game 50(2):100-113.

Bayless, J.D. 1972. Artificial Propagation and Hybridization of Striped Bass, Morone saxatilis (Walbaum). S.C. Wild. Mar. Resour. Dept.

135 pp.

Beck, A*D. and the Committee on Entrainment. 1978. Cumulative effects--

A field assessment, in Power Plant Entrainment--A BiologicalIAssessment

.(J.R. Schubel and B.- Marcy, Jr., eds.), pp. 189-210. Academic, New York.

Bonn, E.W. (Chairman) and the Striped Bass Committee of the Southern Division of American Fisheries Society. 1976. Guidelines for Striped Bass Culture. AFS, South. Div. 103 pp.

Boreman, J. and C.P. Goodyear. 1980. Biases in the estimation of entrainment mortality, in Issues Associated with Impact Assessment, Proc. of the Fifth National Workshop on Entrainment and Impingement (L.D. Jensen, ed.), pp. 79-89. EA Communications, Sparks, Md.

Cada, G.F., J.S. Suffern, K.D. Kumar, and J.A. Solomen. 1980. Investi-gations of entrainment mortality among larval and juvenile fishes using a power plant simulator, in Issues Associated with Impact Assessment, Proc. of the Fifth NationaT Workshop on Entrainment and Impingement (L.D. Jensen, ed.), pp. 111-122. EA Communications, Sparks, Md.

Consolidated Edison Company of New York, Inc. 1977a. Indian Point Unit No..2, Indian Point Unit No. 3. Near-Field Effects of Once-Through Cooling System Operation on Hudson River Biota. Consolidated Edison Company of New York, Inc., Power Authority of the State of New York.

July.

Consolidated Edison Company of New York, Inc. 1977b. Routine Monthly Thermal Monitoring Report. October 1976.

Consolidated Edison Company of New York, Inc. 1978. Indian Point Gener-ating Station, a 316(a) Demonstration. 86 pp.

Consolidated Edison Company of New York, Inc. 1980. Monthly Section 401 Certification Data, April-July 1980. Prepared for the Commissioner, New York State Department of Environmental Conservation. Buchanan, New York.

Coutant, C.C. and R.J. Kedl. 1975. Survival of Larval Striped Bass Exposed to Fluid-Induced and Thermal Stresses in a Simulated Condenser Tube. Report No. ORNL-TM-4695. Oak Ridge National Laboratory, Oak Ridge, Tenn.

Dahlberg, M.D. 1979. A review of survival rates of fish eggs and larvae in relation to impact assessments. Mar. Fish. Rev. 41(3):1-12.

Duncan,. A.J. 1974. Quality Control and Industrial Statistics, 4th Edition. Richard D. Irwin, Inc., Homewood, Ill.

Ebey, S.F. and J.J. Beauchamp. 1977. Larval fish, power plants, and Buffon's needle problem. Am. Math. Monthly 84(7):534-541.

Ecological Analysts, Inc. 1978a. Indian Point Generating Station Entrainment Survival and Related Studies. 1977 Annual Report.

Prepared for Consolidated Edison Company of New York, Inc. EA, Middletown, N.Y.

Ecological Analysts, Inc. 1978b. Hudson River Thermal Effects Studies for Representative Species--Final Report. Prepared for Central Hudson Gas and Electric Corp., Consolidated Edison Company of New York, Inc.,

and Orange and Rockland Utilities, Inc. EA, Middletown, N.Y.

Ecological Analysts, Inc. 1978c. Field Studies of the Effects of Thermal Discharges from Roseton and Danskammer Point Generating Sta-tions on Hudson River Fishes. Prepared for Central Hudson Gas and Electric Corp. EA, Middletown, N.Y.

Ecological Analysts, Inc. 1979a. Indian Point Generating Station Entrainment Survival and Related Studies. 1978 Annual Report. Pre-pared for Consolidated Edison Company of New York, Inc. and Power Authority of the State of New York. EA, Middletown, N.Y.

Ecological Analysts, Inc. 1979b. Ichthyoplankton Entrainment Survival and Abundance Sampling Study Research and Development of Gear and Methods. Prepared for Empire State Electric Energy Research Corpora-tion.ý EA, Middletown, N.Y.

Ecological Analysts, Inc. 1979c. Evaluation of the Effectiveness of a Continuously Operating Fine Meshed Traveling Screen for Reducing Ichthyoplankton Entrainment at the Indian Point Generating Station.

Prepared for Central Hudson Gas and Electric Corporation, Consolidated Edison Company of New York, Inc., Orange and Rockland Utilities, Inc.,

and Power Authority of the State of New York. EA, Middletown, N.Y.

Ecological Analysts, Inc. 1979d. 1978 Annual Report of the Bowline Point Generating Station Entrainment Abundance and Related Studies.

Prepared for Orange and Rockland Utilities, Inc. EA, Middletown, N.Y.

Ecological Analysts, Inc. 1980. Indian Point Generating Station Entrainment and Near Field River Studies. 1978 Annual Report.

Prepared for Consolidated Edison Company of New York, Inc. and Power Authority of the State of New York. EA, Middletown, N.Y.

Ecological Analysts, Inc. 1981. Indian Point Generating Station Entrainment Survival and Related Studies. 1979 Annual Report.

Prepared for Consolidated Edison Company of New York, Inc. and Power Authority of the State of New York. EA, Middletown, N.Y.

Farris, D.A. 1960. The effect of three different types of growth curves on estimates of larval fish survival. Int. Council Explor. Sea Journal Conseil. 25(3):294-306.

Gross, A.J. and V.A. Clark. 1975. Survival Distribution: Reliability Applications in the Biomedical Sciences. John Wiley, New York.

331 pp.

Hackney, P.A. and J.C. Webb. 1978. A method for determining growth and mortality rates of ichthyoplankton, in Fourth National Workshop on Entrainment and Impingement (L.D. Jensen, ed.), pp. 115-124. EA Com-munications, Melville, New York. Available from Ecological Analysts, Inc., Sparks, Md.

Jinks, S., T. Cannon, 0. Latimer, L. Claflin, and G. Lauer. 1978.

An approach for the analysis of striped bass entrainment survival at Hudson River power plants, in Fourth National Workshop on Entrainment and Impingement (L.D. Jensen, ed.), pp. 343-350. EA Communications, Melville, New York. Available from Ecological Analysts, Inc.,

Sparks, Md.

Lal, K., R. Lasker, and A. Kuljis. 1977. Acclimation and rearing of striped bass larvae in sea water. Calif. Fish and Game 63(4):210-218.

Lauer, G.J., W.T. Waller, D.W. Bath, W. Meeks, R. Heffner, T. Ginn, L. Zubarik, P. Bibko, and P.C. Storm. 1974. Entrainment studies on Hudson River organisms, in Proceedings of the Second Entrainment and Intake Screening Workshop-(L.D. Jensen, ed.), pp. 37-82. Johns Hopkins University Cooling Water Research Project Rep. No. 15. Baltimore, Maryland.

Lewis, W.M. and R.C. Heidinger. 1981. Tank Culture of Striped Bass Production Manual. IDC F-26-R. Illinois Striped Bass Project.

McFadden, J.T., Texas Instruments Incorporated, and Lawler, Matusky and Skelly Engineers. 1978. Influence of the Proposed Cornwall Pumped Storage Project and Steam Electric Generating Plants on the Hudson River Estuary with Emphasis on Striped Bass and Other Fish Populations (Revised). Prepared for Consolidated Edison Company of New York, Inc.

Marcy, B.C., Jr., A.D. Beck, and R.E. Ulanowicz. 1978. Effects and impacts of physical stress, in Power Plant Entrainment--A Biological Assessment (J. R. Schubel and B. C. Marcy, Jr., eds.), pp. 135-138.

Academic. New York.

New York University Medical Center (NYU). 1973. Effects of Entrainment by the Indian Point Plant on Hudson River Biota. Progress Report for 1971 and 1972. Prepared for Consolidated Edison Company of New York, Inc. by NYU Medical Center, Institute of Environmental Medicine, Laboratory for Environmental Studies.

New York University Medical Center. 1976. Mortality of Striped Bass Eggs 'and Larvae in Nets. Prepared for Consolidated Edison Company of New York, Inc. by NYU Medical Center, Institute of Environmental Medi-cine, Laboratory for Environmental Studies.

New York University Medical Center. 1978. The Effects of Entrainment by the Indian Point Power Plant on Biota in the Hudson River Estuary.

Progress Report for 1976. Prepared by NYU Medical Center, Institute of Environmental Medicine, Laboratory for Environmental Studies.

New York University Medical Center. 1979. Power Plant Entrainment Simu-lation Utilizing a Condenser Tube Simulator; Results of Experimental Exposure of Striped Bass Early Life History Stages, Gammarus spp. and Neomysis americana to Variations in Temperature, Flow Rate and Biocide Concentrations. Prepared for NYSERDA.

O'Connor, J.M. and G.V. Poje. 1979. Power Plant Entrainment Simulation Utilizing a Condenser Tube Simulator. NUREG/CR-0894. U. S. Nuclear Reguliatory Commission, Washington.

O'Connor, J.M. and S.A. Schaffer. 1977. The effects of sampling gear on the survival of striped bass ichthyoplankton. Chesapeake Sci. 18(3):

312-315.

Pearcy, W.G. 1962. Ecology of an estuarine population of winter flounder, Pseudopleuronectes americanus (Walbaum). Bull. Bingham Oceanogr. Collect. 18:1-78.

SchubelI, J.R., H.H. Carter, and J.M. O'Connor. 1979. Effects of Increasing AT on Power Plant Entrainment Mortality at Indian Point, New York. Special Report 19. Marine Sciences Research Center, State University of New York, Stony Brook.

Schubel, J.R. and B.C. Marcy, Jr. (eds.) 1978. Power Plant Entrain-ment--A Biological Assessment. Academic Press, New York. 271 pp.

Sette, O.E. 1943. Biology of the Atlantic mackerel (Scomber scombrus) of North America. Part I: Early life history, including the growth, drift, and mortality of the egg and larval population. Fish. Bull.

50:149-237.

Sokal, R.R. and F.J. Rohlf. 1969. Biometry--The Principles and Practice of Statistics in Biological Research. W. H. Freeman and Company, San Francisco.

Texas Instruments, Incorporated. 1980. 1978 Year Class Report for the Multiplant Impact Study of the Hudson River Estuary. Prepared for Consolidated Edison Company of New York, Inc. by TI, Dallas.

APPENDIX A ESTIMATED CIRCULATING WATER FLOW AT UNITS 1, 2, AND 3

TABLE A-1 ESTIMATED CIRCULATING WATER FLOW (including service water)

AT UNIT 1, INDIAN POINT GENERATING STATION, DURING ENTRAINMENT SURVIVAL STUDIES,APRIL-JULY 1980 (million m /day)

Month DAY APR MAY JUN JUL

1. 0.101 0.104 0.104 0.104 2 0.104 0.104 0.104 0.104 3 0.104 0.104 0.104 0.104 4 0.104 0.104 0.104 0.104 5 0.104 0.104 0.104 0.104 6 0.104 0.104 0.104 0.104 7 0.104 0.104 0.104 0.104 8 0.104 0.104 0.104 0.104 9 0.104 0.104 0.104 0.104 10 0.104 0.104 0.104 0.104 11 0.104 0.104 0.104 0.104 12 0.104 0.104 0.104 0.104 13 0.104 0.104 0.104 0.104 14 0.104 0.104 0.104 0.104

.15 0.104 0.104 0.104 0.432 16 0.104 0.104 0.104 0.142 17 0.104 0.104 0.104 0.104 18 0.104 0.104 0.104 0.104 19 0.104 0.104 0.104 0.104 20 0.104 0.104 0.104 0.104 21 0.104 0.104 0.104 0.104 22 0.104 0.104 0.104 0.104 23 0.104 0.104 0.104 0.104 24 0.104 0.104 0.104 0.104 25 0.104 0.104 0.104 0.104 26 0.104 0.104 0.104 0.104 27 0.100 0.104 0.104 0.104 28 0.104 0.104 0.104 0.104 29 0.104 0.104 0.104 0.104 30 0.104 0.104 0.104 0.104 31 --- 0.104 --- 0.294 Source: Con Edison 1980.

TABLE A-2 ESTIMATED CIRCULATING WATER FLOW (including service water) AT UNIT 2, INDIAN POINT GENERATING STATION, DURING ENTRAINMENT SURVIVAL STUDIES APRIL-JULY 1980 (million I m I 3/day)'

1 1 Month DAY APR MAY JUN JUL 1 2.845 3.924 3.924 3.924 2 2.828 3.772 3.672 3.924 3 2.829 3.459 2.463 3.924 4 2.669 4.512 2.848 3.924 5 2.732 4.687 2.398 3.927 6 2.856 4.687 2.398 3.952 7 2.856 4.687 1.917 4.137 2.706 4.230 0.124 4.715 2.669 3.925 0.136 4.731 10 2.597 3.924 0.111 4.715 11 3.627 3.924 1.142 4.715 1? 4.086 3.734 3.937 4.333 13 4.077 3.840 3.936 4.715 14 4.039 4.153 3.952 4.509 15 4.687 4.283 3.952 3.746 16 4.687 3.924 3.934 4.516 17 4.184 3.924 3.924 4.715 18 4.550 3.924 3.924 4.715 19 4.245 3.924 3.924 4.715 20 3.924 3.924 3.924 4.722 21 3.176 3.924 3.924 4.742 22 2.421 3.924 3.924 4.742 23 3.421 3.924 3.924 4.742 24, 3.611 3.912 3.924 4.742 25 3.665 3.897 3.924 4.742 26 3.924 3.897 3.924 4.742 27 3.767 3.923 3.924 4.742 28 3.924 3.924 3.924 4.742 29 3.924 3.924 3.924 4.742 30 3.925 3.924 3.924 4.742 31 3.924 4.742 Source: Con Edison 1980.

TABLE A-3 ESTIMATED CIRCULATING WATER FLOW (including service water) AT UNIT 3, INDIAN POINT GENERATING STATION, DURING ENTRAINMtENT SURVIVAL STUDIES APRIL-JULY 1980 (million m3 /day)

Month

.DAY APR MAY JUN JUL 1 2.462 3.188 3.829 3.952 2 2.439 3.188 3.952 3.952 3 2.375 3.188 3.944 3.952 4 2.007 3.188 3.952 3.9 52 5 1.862 3.196 3.952 3.9 52 6 1.367 3.570 3.952 3.952 7 0.804 3.9 52 3.952 3.952 8 0.636 3.952 3.952 3.952 9 0.621 3.952 3.952 3.952 10 0.356 3.952 3.952 3.952 11 0.652 3.952 3.433 3.952 12 0.928 3.950 2.929 3.9 52 13 0.904 3.947 3.952 3.952 14 1.393 3.952 3.952 3.9 52 15 1.663 3.952 3.9 52 16 1.659 3.952 3.952 1.868 17 1.662 3.188 3.952 1.567 18 1.662 3.303 3.952 0.927 19 1.861 3.311 3.952 0.927 20 2.425 3.311 3.952 0.927 21 2.425 3.822 3.9§52 0.927 22 2.425 3.532 3.952 0.927 23 2.425 3.509 3.952 0.927 24 2.082 3.9 52 3.9 52 0.9 27 25 1.701 3.196 3.952 0.927 26 2.425 3.188 3.952 0.927 27 2.344 3.188 3.9 52 0.927 28 2.525 3.188 3.952 0.927 29 3.188 3.257 3.952 2.247 30 3.188 3.669 3.952 2.849 31 3.417 3.807 Source: CIon Edison 1980.

APPENDIX B GEAR SPECIFICATIONS AND SAMPLING CONDITIONS

TABLE B-i SAMPLING GEAR SPECIFICATIONS AND ASSOCIATED SAMPLING CONDITIONS FOR THE SPRING-SUMMER (striped bass, white perch, herring, and anchovy) ENTRAINMENT SURVIVAL STUDY, INDIAN POINT GENERATING STATION, 30 APRIL - 10 JULY 1980 Station 13 DP Collection device Floating, rear-draw Floating, pumpless plankton sampling plankton sampling flume flume Depth of removal(a) 3.6 m (12.0 ft) 3.6 m (12.0 ft)

Collection device 15.2 cm (6 in.) 15.2 cm (6 in.)

intake diameter Elevation of collec- 0.6 m (2 ft) 0.0 m (0.0 ft) tion device with floating floating respect tQ water surface(b-Length of tubing from 10.4 m (34 ft) 10.4 m (34 ft) point of removal to collection device Flow rate 600-1,450 £/min 687-1,720 i/min (159-383 gpm) (182-454 gpm)

Duration of sample 15 min 15-16 min 3 3 Volume sampled per 11.0-21.0 m 8.6-25.8 m collection (2,906-5,548 gal) (2,272-6,816 gal)

Orientation of tubing Horizontally, facing Horizontally, facing relative to water the current the current flow Drain time 15-37 min 15-47 min Sample water depth 25.4-73.7 cm 22.9-53.3 cm in collection device (10-29 in.) (9-21 in.)

(a) Depth of removal refers to the measurements from sample depth to the water surface at mean low water.

(b) Elevation of collection device refers to the level of the bottom of the collection device (flume) relative-to the water surface.

APPENDIX C LENGTH-FREQUENCY DISTRIBUTION DATA

TABLE C-1 LENGTH FREQUENCY DISTRIBUTION BY SAMPLING WEEK FOR ATLANTIC TOMCOD COLLECTED AT STATIONS 13 AND DP FOR ENTRAINMENT SAMPLING, INDIAN POINT GENERATING STATION, 1980 Mean Standard Length Intervals (mm)

No. of Length Deviation 00.0- 20.0- 25.0- 30.0- 35.0- 40.0- 45.0- 50.0- Range (m(a)

Week of Fish (or) (0) 19..9 24.9 29.9 34.9 39.9 44.9 49.9 54.9 55.0+ min Med max Station 13 30 APR 80 11 28.5 3.5 0 1 6 3 1 0 0 00 0' 23.0 28.0 35.0 1 0 1 3 5 0 0 0 14.0 34.5 39.0 12 MAY 80 10 32.7 7.0 0 0 0 0 0 0.0 0.0 0.0 19 MAY 80 0 0.0 0,0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 27 MAY 80 0 0.0 0.0 0 0 0 0 0 0 0. 0 0 0.0 0.0 0.0 2JUN 80 0 0.0 0.0 0 0 0 0 0 0.0 0.0 0.0 9 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 16 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 23 JUN 80 0 0.0 0.0 0 0 0 0 0 0.0 0.0 0.0 30 JUN 80 0 0.0 0.0 0 0 0- 0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 7 JUL 80 0 0.0 0.0 Station DP 30 APR 80 6 26.2 3.6 0 3 1 2 0 0 0 00 0 21.0 26.5 30.0 12 MAY 80 50 31.7 3.6 0 3 7 29 10 1 0 0 23.0 32.0 40.0 19 MAY 80 0 0.0 0.0 .0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 0 0 0 0 2 5 3 1 43.0 47.0 62.0 27 MAY 80 11 48.6 5.3 0 0 0 46.0 46.0 2 JUN 80 1 46.0 0.0 0 0 0 0 0 0 1 46.0 9 JUN 80 1 52.0 0.0 0 0 0 0 0 0 0 1 0 52.0 52.0 52.0 16 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 23 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 30 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 7 JUL 80 0 0.0 0.0 0 0 0 0 0 o 0 0 0 0.0 0.0 0.0 (a) Min = shortest length, led = median length, Max = greatest length.

TABLE C-2 LENGTH FREQUENCY DISTRIBUTION BY SAMPLING WEEK FOR STRIPED BASS COLLECTED AT STATIONS 13 AND DP FOR ENTRAINMENT SAMPLING. INDIAN POINT GENERATING STATION, 1980 Mean Standard Length Intervals (mm)

No. of Length Deviation 0.0- 4.0- 6.0- 8.0- 10.0- 12.0- 14.0- 16.0- Range nn)(a)

Week of Fish (m) (mm) 3.9 5.9 7.9 9.9 11.9 13.9 15.9 17.9 18.0+ n Red Max Station 13 30 APR 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 12 MAY 80 9 5.2 0.9 0 4 5 0 0 0 0 0 0 4.0 6.0 6.0 19 MAY80 20 6.0 0.7 0 5 15 0 0 0 0 0 0 5.0 6.0 7.0 27 MAY 80 32 7.3 0.9 0 1 17 14 0 0 0 0 0 5.0 7.0 9.0 2 JUN 80 15 7.7 1.8 0 0 10 2 2 I 0 0 0 6.0 7.0 12.0 9 JUN 80 71 8.8 1.8 0 0 19 26 20 6 0 0 0 6.0 9.0 13.0 16 JUN 80 60 10.1 .1.9 0 0 3 19 27 8 2 1 0 6.0 10.0 16.0 23 JUN 80 3 11.7 0.5 0 0 0 0 1 2 0 0 11.0 12.0 12.0 30 JUN 80 5 12.0 2.9 0 0 1 0 0 3 0 0I 0 7.0 12.0 16.0 7 JUL 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 Station DP - 0 30 APR 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 12 MAY80 7 4.7 0.9 0 5 2 0 0 0 0 0 0 4.0 4.0 6.0 19 MAY 80 6 ý.7 0.1 0 2 4 0 0 0 0 0 0 5.0 6.0 6.0 27 MAY80 18 7.1 1.0 0 1 11 6 0 0 0 00 0 5.0 7.0 9.0 2 JUN 80 15 8.3 1.3 0 0 4 9 2 0 0 0 0 6.0 8.0 11.0 9 JUN 80 27 9.9 2.0 0 0 4 8 9 6 0 0 7.0 10.0 13.0 16 JUN 80 144 10.7 1.8 0 0 4 21 78 31 9 1 1 6.0 10.5 18.0 23 JUN 80 6 11.5 3.1 0 0 1 0 2 2 0 8 0 6.0 12.0 16.0 30 JUN 80 20 15.7 5.4 0 0 0 1 2 4 3 2 8.0 15.5 31.0 0

7 JUL 80 4 23.5 11.1 0 0 0 0 1 0 1 2 11.0 23.5 36.0 (a) Mmin= shortest length, Med = median length, Max = greatest length.

TABLE C-3 LENGTH FREQUENCY DISTRIBUTION BY SAMPLING WEEK FOR WHITE PERCH COLLECTED AT STATIONS 13 AND DP FOR ENTRAINMENT SAMPLING, INDIAN POINT GENERATING STATION. 1980 mean Standard Length Intervals (nn) (a)

No. of Length Deviation O.0- 4.0- 6.0- 8.0- 10.0- 12.0- 14.0- 15 Ranae )_

Week of Fish ( ( rm) 3.9 5.9 7.9 9.9 11.9 13.9 15.9 17.9 18.0+ min Red max Station 13 30 APR 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 12 MAY 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 19 MAY 80 0 0.0 0.0 0 0 0 0" 0 0 0 0 0 0.0 0.0 0.0 27 MAY 80 3. 6.0 0.8 0 1 2 0 0 0 0 0 0 5.0 6.0 7.0 2 JUN 80 4 8.5 2.2 0 1 0 2 1 0 0 0 0 5.0 9.0 11.0 15 9.7 1.9 0 1 0 4 8 2 0 0 0 4.0 10.0 12.0 9 JUN 80 1 16 JUN 80 46 10.1 1.7 0 1 13 24 7 0 0 0 4.0 10.0 13.0 23 JUN 80 14 6.6 2.4 0 6 3 3 2 0 0 0 0. 4.0 6.0 11.0 30 JUN 80 20 10.5 2.7 0 1 2 4 5 5 3 0 0 5.0 11.0 14.0 7 JUL 80 9 9.9 2.8 0 1 0 3 2 3 0 0 0 4.0 11.0 13.0 Station DP 30 APR 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 12 MAY 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 19 MAY80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 27 MAY 80 .3 5.0 0.0 0 3 0 0 0 0 0 0 0 5.0 5.0 5.0 2 JUN 80 2 9.0 1.0 0 0 0 1 1 0 0 0 0 8.0 9.0 10.0 9 JUN 80 17 8.8 2.4 0 2 3 4 6 2 0 0 0 4.0 9.0 12.0 16 JUN 80 84 10.7 1.8 0 2 2 10 41 29 0 0 0 4.0 11.0 13.0 23 JUN 80 15 5.9 2.2 0 8 4 1 2 0 0 0 0 4.0 5.0 11.0 30 JUN 80 44 12.3 1.9 0 0 0 4 10 17 12 1 0 8.0 13.0 16.0 7 JUL 80 10 11.4 1.9 0 0 0 2 2 4 2 0 0 8.0 12.0 14.0 (a) Mn = shortest length, Ned = median length,.Max = greatest length.

TABLE C-4 LENGTH FREQUENCY DISTRIBUTION BY SAMPLING WEEK FOR HERRING COLLECTED AT STATIONS 13 AND DP FOR ENTRAINMENT SAMPLING. INDIAN POINT GENERATING STATION, 1980 Mean Standard Length Intervals (nmn)

No. of Length Deviation 0.0- 4.0- 6.0- 8.0- 10.0- 12.0- 14.0- 16.0- (rm)

Week of Fish (mm) (nun) 3.9 5.9 7.9 9.9 11.9 13.9 15.9 17.9 18.0+

• fn FedM ax Station 13 30 APR 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 12 MAY 80 1 1.0 0.0 0 0 I 0 0 0 0 0 0 7.0 7.0 7.0 19 MAY 80 3 7.3 2.6 0 1 0 1 0 0 0 0 5.0 6.0 11.0 27 MAY 80 2 6.5 0.5 0 0 2 0 0 0 0 0 0 6.0 6.5 7.0 2 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 9 JUN 80 2 9.0 0.0 0 0 0 2 0 0 0 0 0 9.0 9.0 9.0 16 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 23 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 30 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 7 JUL 80 2 63.0 1.0 0 0 0 0 0 0 0 0 2 62.0 63.0 64.0 Station DP 0 30 APR 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0.

12 MAY 80 5 6.4 0.5 0 0 5 0 0 0 0 0 0 6.0 6.0 7.0 19 MAY 80 2 7.5 0.5 0 0 1 0 0 0 0 0 7.0 7.5 8.0 27 MAY 80 2 8.0 1.0 0 0 10 0 0 0 0 0 7.0 8.0 9.0 2 JUN 80 4 11.0 0.7 0 0 0 0 3 1 0 0 0 10.0 11.0 12.0 9 JUN 80 1 17.0 0.0 0 0 0 0 0 0 0 1 0 17.0 17.0 17.0 16 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0

'1 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 3d JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 7 JUL 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 (a) Min = shortest length, Mied w median length, Max = greatest length.

TABLE C-5 LENGTH FREQUENCY DISTRIBUTION BY SAMPLING WEEK FOR ANCHOVIES COLLECTED AT STATIONS 13 AND DP FOR ENTRAINMENT SAMPLING, INDIAN POINT GENERATING STATION, 1980 Mean Standard Length Intervals (mm)....

No. of Length Deviation 0.0- 4.0- 6.0- 8.0- 10.0- 120- 14.0- 16.0- Range (mm)a)

Week of Fish ) (mm) 3.9 5.9 7.9 9.9 11.9 13.9 15.9 17.9 18.0+ Med max Station 13 30 APR 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 12 MAY 80 0 0.0 0 0 0.0 0.0 0.0 19 MAY 80 0 0.0 0.0 0 0 0 0 0 0 0 0.0 0 0 0 0 0 0 0 0 '0 0.0 0.0 0.0 27 MAY 80 0 0.0 0 0.0 0.0 0.0 0.0 0 0 0 0 0 0 0 0 2 JUN 80 0 0.0 0 0 0.0 0.0 0.0 9 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0.0 0 0 0 0 1 0 0 0 0 11.0 11.0 11.0 16 JUN 80 1 11.0 4 2 4.0 11.0 20.0 23 JUN 80 112 10.4 4.0 0 15 26 5 13 19 28 30 JUN 80 66 7.1 2.5 0 17 27 18 2 0 0 1 1 4.0 7.0 19.0 7 JUL 80 44 10.0 3.2 0 0 9 18 6 2 5 4 0 6.0 9.0 17.0 Station DP 30 APR 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 12 MAY80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 19 MAY 80 0 0.0 0.0 0 0 0 0. 0 0 0 0 0 0.0 0.0 0.0 27 MAY80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 2 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 9 JUN 80 0 0.0 0.0 0 0 0 0 0 0 0 0 0 0.0 0.0 0.0 16 JUN 80 4 11.8 3.0 0 0 0 1 1 1 0 1 0 8.0 11.5 16.0 23 JUN 80 226 9.7 5.3 16 70 16 9 14 32 31 22 16 3.0 10.5 22.0 30 JUN 80 72 6.4 2.0 0 26 32 12 1 0 0 0 1 4.0 6.0 18.0 7 JUL 80 109 10.5 5.1 0 12 24 31 7 4 7 9 15 4.0 9.0 28.0 (a) Min = shortest length, Med = median length, Max = greatest length.