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TECHNICAL REPORT TO THE CALIFORNIA COASTAL COMMISSION

C. Entranment of .Iuvenileand Adult Fish at SONGS

MARINE REVIEWCOMMITTEE. INC.

WilliamW. Murdoch,Chairman Universityof California ByronJ. Mechalas SouthernCalifornia Edison Company Rimmon C. Fav PacificBio-Marine Iibs. Inc.

Preparedby: SusanL. Swarbrick RichardF. Ambrose

PrincipalInvestigators, Fish Project: EdwardDeMartini Ralph Larson Larrv Allen

July1989 This report analyzesand presentsthe resultsof studiesof the UCSB Fish lrogram, which,weredone on behalfof the MRC over the period 1980-1988,under the direction of Dr Edward E. DeMartini. Dr. DeMartini's Final Report to the MRC "The Effects of Operationsof the San Onofre Nuclear GeneratingStation on Fish" (December1987) provided the startingpoint for the analysesinlhe present report.

TECHNICAL REPORT C. ENTRAPMENT OF JUVENILE AND ADULT FISH AT SONGS CONTRIBUTING STAFF: Todd Anderson BonnieM. Williamson I

I TABLE OF CONTENTS t Summary l.INTRODUCNON T L.1Objectives I 2. METHODS 2.1Estimates of entrapmentat SONGS...... 2.1,.L.Impingement samples ...... t 2.L.2.Diversion samples .... 2.1.3.Heat treatmentsamples 1.1.Comparison of entrapment'atUnits Z and3...... 2.3.Annual entrapment dt SONGS...... I 2.3.1.Estimbtion of annualentrapment...... 2.3.2.Estimating entrapment at Unit 1 from entrapmentat Units2 and3...... 11 I 2.4.EvaIuationof ihe efficiencyof the Fish Return System(FRS)...... 13 t3 2.4.2.Percent survivorship...... L4 t 3. RESULTS 20 20 t 20 22 25 3.2.1,.Percent diversion.. 25 I 3.2.2.Percent survivorship...... 26 3.2.3.Efficiency of the FishReturn Svstem... 29 I 3.3Estimated losses at SONGS 30 4. DISCUSSION 32 I 4.1.Entrapment and lossesat SONGS 32 1.?.Tppporal comparisonsof the magnitudeof entrapment...... 32 4.3.Fish Return System...... 34 4.3.1 Percentdiversion...... 34 I 4.3.2Survivorship..... 35 I 5. REFERENCES 39 6. TABLES 43 I 7. FIGURES 7r I t I I

APPENDICES I I APPENDIX A...... A-1 Comparisonof entrapmentat Units2 and3...... A-1 Comparisonof entrapmentat differentflow vo1umes...... A-1 t Comparisonof entrapmentat Unit 1 with Units2 and3...... A-2

APPENDIX B I Data Sourcesfor Tables B-1 I I I T I I I I I I I I t I I

I SUMMARY I SONGS withdraws cooling water from the ocean through intake pipes I situatedin 9 m of water about 1 km offshore. When all pumpsare operating,L0.8 x 106m3 of water passesthrough the three units daily. Juvenile and adult fish are I drawn into the plant with the coolingwater. I All the fish that enter Unit 1 are killed; they are either impinged on I travelling screens,pass through the screens,or remain in the screenwellsuntil they are killed by periodic heat treatmentsthat are used to control the accumulationof I biofoulers. Unlike Unit 1, the new units have a Fish Return System(FRS) designed to divert fish past the travelling screensand return them to the ocean.Thus, fish that t enter Units 2 ar;rd3 are impinged on screens,extruded through the screens,killed in I heat treatments or diverted through the FRS. In this report we have estimated entrapment of fish at SONGS and evaluated the efficiency of the Fish Return I Systemin reducingthe lossof fish at Units 2 and3.

I Annual entrapment was estimated from samples collected at the three I SONGS units during the 39-monthperiod from May 1983to August 1986. Almost sixmillion fish weighing41.1 metric tons (MT) were entrappedannually at SONGS. t Only 5Vo of the total number and 10Vo(4.2 MT) of the total biomasswere entrappedat Unit 1. More than 98Voof the 5.6 million fish entrappedat Units 2 I and 3 were small species.Two of them, northern anchovyand queenfish,accounted for 75Vo and 20Vo,of the fish entrapped,but they were small and comprisedonly I 13Voand 39Vo,of the biomass. lrss than 2Vo of.the entrappedfish were medium I and large species,but becauseof their size,they represented13%o and,31.Vo of the biomass,respectively. These t estimatesof annualentrapment are too low because I lll I I somesmall fish passedthrough the travellingscreens in all threeunits and couldnot be sampled. While the abundanceof fish may be substantiallyunderestimated by I the loss of theseindividuals. the effect on estimatesof biomassis smallerbecause the fish are small. I I At Units 2 and 3, most entrappedfish were diverted through the FRS and returnedto the ocean. About 794,000fish (7.2 MT) were impingedon travelling I screens,66,000 fish (3.0 MT) were killed in heat treatmentsand 4.7 million fish (26.6MT) were divertedthrough the FRS. In general,medium and large species I were more likely to be diverted than small ones. For most species,individuals that I were divertedwere, on average,larger than thosethat were impinged. However,for many of the abundantspecies, including white croaker,yellowfin croaker,sargo and I zebraperch, the largestindividuals were killed in heat treatments. I The efficiencyof the FRS at SONGSUnits 2 and 3 is defined as the percent of the fish entrappedin the plant that are returnedto the oceanalive. Efficiencyis I the productof the percentageof entrappedfish that are divertedto the FRS return I conduit (percent diversion)and the percent survivorshipof diverted fish. Estimates of the probability of survivingtransport through the FRS include mortality up to 4 I daysafter discharge. Mortality resulted from physiologicaldamage incurred while fish were in the FRS and was estimatedfrom experimentaldata. Estimatesfor most I speciesare unreliabledue to poor replicationand lack of controls,but we include t them becausethey are the only estimatesavailable. I Percentdiversion estimates for individualspecies ranged from 4LVoto 94Vo of the numberand from 49Voto 91Voof the biomassof fish entrappedin Units 2 and I 3. Overall, 68Voof the number and 76Voof the biomassof small specieswere I I I I diverted to the FRS. Percentdiversion of medium specieswas 68Vo for number and I 66Vof.or biomass, and diversionof largespecies was 74Vofor number and,67Vofor I biomass.

I There were too few data to estimate survivorshipof diverted fish for most species. However, we have more confidence in the estimatesfor the two most t abundantspecies, northern anchovyand queenfish,and for the small and large size classesof species.About 97Voof the northern anchovyand 68Voof the queenfish I that were divertedto the FRS survived.These two speciesaccounte d for 98Voof the I fish in the small size class. Survivorship for large specieswas almost 100Vo. Survivorshipfor medium speciescould not be estimatedaccurately; it could range I fromTTVoto 95Vo.These are estimatesof maximumsurvivorship; because they do not include mortality from FRS effects that are lethal more than 4 days (the t durationof eachexperiment) after fish were dischargedfrom the plant. I Estimatesof the efficienry of the FRS are also maximumestimates since they I dependon percentsurvival of fish dischargedfrom the FRS. Efficiencyof the FRS ranged from a low of about 25Vo for white croaker to a high of about 90Vo for I walleye surfperchand salema. Efficiency for northern anchory was relatively high; 87Voof the number and 76Voof the biomassof entrappedfish were returnedto the I ocean and survived for the four days that they were observedin the FRS study. I Efficiency for queenfish was only 48Vo for number and 53%o for biomass of entrapped fish. The FRS seemedmost efficient for large species;efficiency wz6 I 74Vo for number and,67Vo for biomass. On average,about 50Vo of fish in the medium and small (excluding anchovy) size classeswere returned and survived. I Smallspecies were sucha dominantcomponent of the fish entrappedat Units 2 and I 3 that they accountedfor almost98Vo of the fish that survivedeven though they had t t I the lowestprobability of survivingFRS transport. Smallspecies represente d 54Voof the biomasssuccessfully returned while medium and large speciescomprised 1L7o I and35%o,respectively. Overall, the FRS successfullyreturned 4.33 million fish (21.9 I MT) representing77Vo of the fish (59Voof the biomass)entrapped at Units 2 and3. I During May 1983to August L986,about272,000juvenile and adult fish (a.2 MT) were entrappedeach year at Unit 1; they all died. Approximately1..27 million I (15.0MT) of the 5.6 million juvenile and adult fish entrappedannually at Units 2 and 3 were killed. Therefore,total annuallosses at SONGSduring this period were I 1..54million fish (19.2 MT). This represents26Vo of the number and 47Voof the I biomassof fish entrappedannually at SONGSduring this period. I Annual estimatesof entrapmentwere basedon samplestaken over a period whenthere wasan unusualbroadscale reduction in the abundanceof nearshorefish I inducedby El Nino. Entrapmentat SONGSdepends on the nearshoreabundance of fish. To estimate future entrapment during periods of higher abundanceof I nearshorefish, entrapmentduring 1983-1986was comparedwith entrapmentduring I 1976-L979,before the El Nino period. If the nearshoreabundance of fish were at 1976-1979levels, then SONGSUnits L,2, and 3 togethermight entrap more than I 110 MT of fish each year (assumingSONGS operatedat 757oof the maximum pumping level). If overall efficiencyof the FRS remainedat the samelevel as 1983- I 1986(47Vo for biomass),then 52 MT of fish would be killed eachyear. I I I I vl T 1. INTRODUCTION

An electricgenerating station that useswater for coolingentrains planktonic fish eggsand larvaeand entrapsjuvenile and adult fish alongwith the water that is drawn into the plant (Sharma1978). Power plants currently operatingin the United Stateswithdraw cooling water from many sources,including lakes, rivers, estuaries I and the ocean. SanOnofre NuclearGenerating Station (SONGS), which is located on the coastof SouthernCalifornia (Figure 1), withdraws water from the ocean. I SONGS withdrawscooling water through intake pipes situatedin 9 m of I water about 1 km from shore (Figure 1). Unit 1, which has two circulating pumps, withdraws1..1 x \U m3f daywhen both pumpsare operating. Each of the new units,

Units 2 and 3, has four circulatingpumps which take in about 4.5 x 1ff m3 f dayat full flow. Thus,when SONGS is fully operational,about 10.7x 1ff m3of water /day passesthrough the plant.

Juvenile and adult fish are drawn into the plant with the cooling water. The structure of the intake systemat Unit 1, which has operatedsince 1968,is different from units 2 and 3, which began operation in May 1983 and April 1984,

respectively. These differencesaffect the magnitudeof entrapmentand the fate of the fish entrapped.

The intake pipe for each unit is coveredwith a velocity cap which various studieshave indicated reducesthe entrapmentrate of adult fish (Thomaset al. 1980,I-awler et a\.1982a,EPRI 1984). The cap coveringthe intakepipe for Unit 1 is rectangular.In contrast,circular caps were installedover intakepipes for Units 2

I I I and 3 becausea circular cap reducesthe variance and vertical components of incurrent flow, two factors believed to influence fish entrapment (Weight 1958, I Schulerand I-arson1975). I In Unit 1, most entrapped fish are impinged on travelling bar racks and I screenswhich have a 5/8-inch mesh size. However,small fish can passthrough the screens(Appendix A). Also, somefish are not immediatelyimpinged on the screens I but remain in the screenwellsuntil they are killed by periodicheat treatmentsthat are used to control the accumulationof biofoulers. After they die, they collect on I the screensand are removed. All fish collected from the screensare taken to a I landfill site. I Units 2 and 3 also have travelling bar racks and screens that collect entrappedfish, but the meshsize of thesescreens is only 3/8 inch. (The maximum I size of fish that can pass through these screensis much smaller than at Unit t I [Appendix A].) Unlike Unit L, the two new units have a fish return system(FRS) designedto reduce lossesof fish by diverting them past the travelling screensand t eventuallyreturning them to the ocean. Thus, of the fish that enter Units 2 or 3, somefish are impingedon (or passthrough) the travellingscreens, some remain in I the screenwellsand are eventuallykilled during periodic heat treatments,and the rest are divertedinto the FRS holdinsbav. I I The successfuloperation of the FRS dependson the behavioralresponses of fish to changesin water velocity and pressure. The FRS consistsof a series of I guidingvanes and louversthat direct fish into a bay of quiet water,where they are held until they are returned to the ocean(Figure 2). The louvers(travelling bar I

2 I T t I racks),which are located to one side of the incomingwater flow in front of the I travellingscreens, are vertical barsthat are about 0.5 cm wide and 6 cm deep,and are spacedabout 3 cm apart. As waterenters the screenwell,the guidingvanes help I directsome fish towardsthe collectionbay; they alsoensure that the flow acrossthe I louvers is uniform so that fish are less likely to be trapped against the louvers in areas of high velocity. Fish that contact the louvers theoretically swim along the t bars and into the collection bay. The collection bay is a large concretelined basin (about5 mlongx4 mwidex 9 mdeep) with a travellingscreen at the back. Water I flows throughthe basinbut the flow is muchslower than in the screenwellarea. I A large rectangularelevator bucket, 4 m long and 1 m deep,sits within the I basin and is used to remove the fish from the collectionbay. The bottom and lower portion of the sidesof the bucket are solid and the top 30 cm on all sidesis mesh. t When the elevatoris activated,most of the fish are trappedin the bucket as it is slowlyraised out of the water. The fish are then dumpedfrom the bucketinto the I return sluice channel as water is flushed into the channel. The front edge of the I bucket is at an angleto the bottom to facilitate the even flow of water and fish over the lip and into the sluice channel (Figure 3). The bucket is repeatedlyraised and I lowereduntil at least90%oof the fish are removedfrom the collectionbay asjudged by the diminishing number in each successivebucket load. Normally, fish are I removed from the collection bay once a day but they may be removed more frequentlyduring periodsof heavyentrapment. The return conduit dischargesthe I fish in 6 m of water about400 m offshore(Figure 1). l I I I I

1.1 Objectives I I The goalsof this report are: (1) to providea comprehensivesummary of the number and biomassof fish entrappedin all 3 SONGS units from May 1983to I August 7986,(2) to estimatethe annualmagnitude of entrapmentfor the period, (3) to evaluatethe efficiency of the Fish Return Systemin reducing the loss of fish at I Units 2 and 3, and (a) to estimatethe potential inplant loss of fish at SONGS in the future. I I This report is a summaryof the work done by DeMartini et al. (1987)for the MRC. We have reviewedtheir results and included new analyseswhen warranted. I DeMartini et al. used the data collected by contractors employed by Southern California Edison to carry out the monitoring studiesof fish entrapmentrequired by t the National Pollutant DischargeElimination System(NPDES) permits for SONGS I Units 2 and 3. The mortality of fish that were dischargedfrom the power plant through the Fish Return System was estimated from a study by researchersat I OccidentalCollege (l,ove et aL 1987). t t I I I I t I I I I 2. METHODS

I The following is a summaryof the methods used to estimateentrapment of fish at SONGSduring the first 39 months(May 1983- August 1986)of operationof I Units 2 and3 and concurrentoperation of Unit 1. In addition, the methodsused to t evaluatethe efficiencyof the Fish Return System(FRS) are summarized. A detaileddescription of methodsused to collectsamples, estimate entrapment, and I evaluatethe FRS canbe found in DeMartini et al. (1986,7987).

I 2.1,.Estimates of entrapmentat SONGS I Fish that enter Units 2 and3 may : (1) passthrough the travelling screens,(2) I be impinged on the screens,(3) be diverted to the FRS, or (4) remain in the I screenwellsuntil they are killed during a heat treatment. At Unit 1, which has no FRS, fish may passthrough the travelling screensor be impinged on them or die in I heat treatments. The abundancesof fish that were impinged, diverted, or killed in heat treatmentswere estimatedseparately. Small fish that passthrough the screens I in Units 2 and,3 could not be sampledand their abundancecannot be estimated. The abundancesof small fish that passedthrough the 5/8"-meshscreens in Unit 1 I but would havebeen collected on 3/8"-meshscreens like thosein Units 2 and3, was I estimated for queenfish,northern anchovy and white croaker, by comparing the length frequencydistributions of fish in Unit 1, and fish in Units 2 and 3 (Appendix I A). I I I I

2.1.1. Impingement samples I I Both numberand biomassof fish impingedon the travellingscreens in each of the three units were estimatedfrom samplesthat spanned24 (t_ 2) hrs of I operationduring full-flow conditions.Full-flow conditions occurred when all pumps operatedfor the entire sampleperiod. The operationalstatus of eachSONGS unit I was determined from a record of the volume of water pumped during the period I and indicated in the Marine Review Committee (MRC) SAS data baseDBFLOW. Table 1 lists the dates from May 1983 through August 1986when quantitative I impingementsamples were taken at eachunit. Sampleswere collectedon 65 days at Unit 1 and on 88 and 103days at Units 2 and3, respectively.Samples were also I taken during periodswhen some pumpswere not operating;these sampleswere usedin a separateanalysis to determinethe relationshipbetween the magnitudeof I entrapmentand the volume of water pumpedthrough a unit. I

Eachunit 6 setsof bar racksand travellingscreens arranged side by side. As I the racksand screensrotate out of the water.fish and debristhat havecollected on the racks and screensare washedinto a sluice channel and collect in large mesh I lines. All fish in a 24 hr impingement sample were collected, identified and counted. Aggregatewet weightswere determinedfor eachspecies. The standard I lengthsof individualsof each of 10 selectspecies, including queenfish,northern anchovy,white croaker,kelp bass,barred sand bass and black croaker,were usually measuredin each24 hr sample. At least 125 fish of each specieswere randomly selectedand measuredwhen present;after November 1983,up to 250 queenfish weremeasured. I I 2.1.2.Diversion samples I The numberand biomassof fish divertedto the Fish Return System(FRS) in I Units 2 and3 were sampledduring the same24 (t_2) hr periodsthat were sampled for impingementon travelling screens(Table 1). However,not all the fish that were I removed from the FRS collection bay during the 24 hr period were counted. I Instead,two subsampleswere collectedeach time the elevatorbucket was emptied, and usedto estimatethe numberof fish divertedthrough the FRS. The samplewas I taken as the fish irl the elevatorbucket were poured into the return sluiceway. Two nets,each with circular openings40 cm in diameter,were haphazardlyposition on I the lip of the bucket,and capturedthe fish that spilledover that sectionof the lip as the bucket was emptied. Since the nets covered20Vo of the 4 m length of the lip, I the sum of all fish captured in nets as successivebucket-loads were emptied, I represents20Vo of the total fish removedfrom the FRS collectionbay.

I All fish in the subsampleswere identified and countedand aggregatewet weights were determined by speciesin the same rnanner as for the impingement I samples. The number and biomassof the subsampleswere then scaledup to t estimatetotal abundanceand biomass. Standardlengths of individualsof the 10 selectspecies (listed abovein impingementsamples) were also measured.At least 125 individuals of each species(250 for queenfish) were randomly chosen for meunurement;if lessthan 125individuals were collected, they were all measured.

A few very large species,such as raysand sharks,were not subsampledwith nets as describedabove. Instead,they were counted,and lengthswere estimated visually,while they remainedin the elevatorbucket, just before it emptied. The I I numberand biomassof thesevery largefish were addedto the scaled-upestimates of the other speciesto determinetotal abundanceand biomassof divertedfish. I

2.1.3.Heat treatmentsamples T

The California Department of Fish and Game requires that all heat I treatmentsat electricalgenerating stations in SouthernCalifornia be monitored. I Therefore,all fish killed during heat treatmentsat SONGSUnits "1,,2and 3 during May 1983- August 1986were collectedfrom travellingscreens, identified, counted I and weightedin the samemanner as impingementsamples. The standardlengths of the selectspecies were alsomeasured. The dateswhen heat treatmentsoccurred at I Units 1,2 and3 are listed in Table 2; therewere 8 heat treatmentsat Unit L, 18 at Unrt2 and 13at Unit 3. I I 2.2, Comparisonof entrapmentat Units 2 and 3 I A comparisonof abundanceand biomassof fish entrappedin Units 2 and3 showedthat there were no statisticallysignificant differencesin the magnitude of I entrapment at the two new units. The top 20 speciescaught in each unit were ranked by both number and biomass. The rankings for Units 2 and 3 were l correlatedwhich suggeststhat the speciescomposition of the fish entrappedin the I two new units is similar. Details of these analysesare presentedin Appendix A. Therefore,estimates of the total numberand biomassof fish impinged,diverted and killed in heat treatmentsare summedover Units 2 and3 in all subsequentanalyses. I I 2.3.Annual entrapmentat SONGS

I 2.3.1.Estimation of annualentrapment I Estimates of entrapment measuredat the three SONGS units during fuU- I flow operationalconditions in the 39-monthperiod from May 1983to August 1986 wereused to estimatethe annualentrapment of fish (both numberand biomass)by t the power plant. Data from both impingementand heat treatment sampleswere used for Unit 1 and the combined data for impingement, diversion and heat I treatment sampleswere usedfor Units 2 and3. t The first step in estimating the annual impingement and diversion I componentsof entrapmentwas to use the quantitative24-hr entrapment samples to calculatethe mean daily entrapmentrate (i.e. the mean number and biomass

I impinged and diverted per day at full flow [all pumps operating] for each unit) for I eachof the 39 months. Therewere somemonths when no entrapmentsamples were taken for a unit, often becausethe unit was not operating at full flow during that I month. At most,two quantitativesamples were collected each week (Table 1).

I The mean daily entrapmentrate at full flow in a month was multiplied by the number of "full-flow" days in that month to estimate monthly entrapment. The I number of "fulI-flow" dayswas calculatedby summingthe volume of water pumped I during the month and dividing by the daily full-flow volume (1.7 x 106m3 for Unit 1 and 4.5 x 106m3 for Unit 2 or 3). The number of "full-flow" daysper month for Units L,2 and3 are shownin Table3. I I This method of estimating monthly entrapment assumesthat both the number and biomassof fish entrappedis positively and linearly related to the I volume of water pumpedover a rangeof 25Voto L00Vopump operationat a unit. I This assumptionwas testedby comparingthe number and biomassof fish entrapped at one new unit operatingat full flow (4 pumps)to entrapmentat the other new unit I that was concurrentlyoperating at lessthan full flow (fewer than 4 pumps). Results showthat entrapmentis a linear functionof the volumeof waterpumped (Appendix I A); for example,twice the volume pumpedentraps nrrice as many fish, on average. I Estimates of monthly entrapment for the 39 months from May 1983 to t August 1986were averagedover years for each month (i.e. Jan., Feb., etc.) to determine the mean monthly entrapment for the sample period. The annual I impingementand diversioncomponents of entrapmentwere calculatedby summing the estimatesof mean monthly entrapment. Monthly entrapmentwas first averaged I over yearsfor eachmonth and then summedover monthsto ensurethat eachmonth was representedequally in the estimatedannual total. This was necessarybecause I the summer months were overrepresentedin the 39-month sample period. I Estimates of annual entrapment are the same as those given in DeMartini et al. (1987). Variancesof the estimatedannual entrapment and a detaileddescription of T the methodsused to calculatethe variancesare alsogiven in DeMartini et al. (1987) andwill not be includedhere. I

Heat treatmentswere not performed on a regular schedule;sometimes severalmonths passedbetween treatments. Sinceheat treatmentssamples may T have containedfish that had collectedin screenwellsover more than one month, "monthly"losses for the 39-monthperiod couldnot be estimated.Annual estimates I

10 I I of heat treatment losses were calculated by summing losses over the 39-month

I sample period and taking 12f39tn"of the total. Annual heat treatment estimates t were added to the annual impingement and diversion estimatesto determine annual entrapment. I The methoddescribed above was used to calculateannual entrapment for all I speciesat Units 2 and 3 and all speciesexcept queenfish, northern anchovy,and white croaker at Unit t. The annual entrapmentrates of queenfish,northern I anchory and white croaker at Unit l were calculatedfrom entrapmentestimates at I Units 2 and3 (seedetails below). I 2.3.2.Estimatingentrapment at Unit 1 from entrapmentat units 2 and 3 I Sincesmall fish were lost from impingementsamples in all units becausethey passedthrough the travelling screens,entrapment of juvenile and small adult fish is I underestimated.The absolutemagnitude of the underestimateis larger for number than for biomass becausesmall fish do not weigh much. Entrapment of small I speciesat Units 2 and 3 is more representativeof actual entrapmentbecause more t small fish are trapped on the small-meshscreens in the new units than on the larger- meshscreens in Unit 1. Therefore,entrapment at Unit 1 for queenfish,northern T anchovyand white croaker, all abundantsmall species,was calculatedfrom annual estimatesat Units 2 and3. l The first stepin estimatingentrapment at Unit 1 from entrapmentat Units 2 I and 3 wasto determinethe ratio of entrapmentat Unit 1 to the new units. Sincethe I volumeof water drawninto Unit 1 is muchless than the volumedrawn into eitherof

I 11 I I t the new units, entrapmentshould also be lower at Unit 1. DeMartini and Larson (1980)predicted that, if meansizes were equal, each new SONGSunit would entrap t 2.5 times the amount of fish entrappedin Unit 1 because,when all pumps are operating,each new unit pumpsabout 21,/2 timesthe amountof water that Unit 1 pumps. The number of fish entrappedat the different units cannot be compared directly becauselarge numbersof small fish that are impinged on screensin Units 2 and 3 passthrough the screensin Unit 1 and are not sampled. To avoid the bias causedby the differencein screenmesh size, only large ( > 100mm SL) queenfish, which shouldbe fully retainedon the larger meshscreens in Unit 1, were usedfor the comparison.A nvo-tailedpaired t-test was used to test the hypothesisthat there was no differencebetween the number of fish entrappedin a new unit and 2.5 times the number of fish entrappedin Unit L. Details of this analysisare presentedin Appendix A.

Resultsshow that the hypothesisthat entrapmentat eitherUnit 2 or Unit 3 is 2.5 times the entrapmentat Unit 1 must be rejectedfor large queenfish. Instead, the number of fish entrappedin eachnew unit is about 7.7 times the number of fish entrappedin Unit 1 (Appendix A Table A-8) and this ratio is used in subsequent calculations.This relationshipalso seemsto be a good approximationfor the ratio of biomassentrapped at the new unitsand Unit 1 (AppendixA).

The ratio of entrapmentat a new unit to entrapmentat Unit 1 was estimated for full-flow conditions (all pumps operating) at all units. However, annual estimatesof entrapmentreflect the averagepumping conditionsover the 39-month samplingperiod. At Units 2 and 3, pumpinglevels averaged 76Vo of the full-flow level but Unit 1 operatedat only 56Voof full flow (Table 3). The differencein

t2 t I pumpingmust be taken into accountwhen entrapmentat Unit 1 is estimatedfrom I entrapmentat Units 2 and3. Therefore,annual entrapment at Unit 1 for queenfish, northernanchovy and white croakerwas estimated as: I ("XT8i,1,?!oili'3j' (numberorbiomass = * o.trt I at Unit 1) 15.4

I where 0.737is the ratio of the averagepumping level at Unit 1 to the new units I (56Vo/ 76Vo)and 15.4is 2 timesthe ratio of entrapmentat a newunit to Unit 1. t 2.4.Evaluation of the efficiencyof the Fish Return System(FRS)

I The efficiencyof the FRS at SONGSUnits 2 and,3is defined as the percent of the fish entrappedin the plant that are returnedto the oceanalive. There areat I leasttwo componentsthat mustbe consideredwhen evaluatingefficiency. The first l is percentdiversion (i.e. the fraction of all fishesentrapped that are divertedto the FRS and ultimately dischargedback into the ocean). The secondis the percent I survivorshipof fishesthat are diverted. Fish that are diverted to the FRS may die either before or shortly after dischargebecause of physiologicalstresses associated t with transport through the FRS. The overall percent efficienry of the FRS is I calculatedas percent diversion times percent survivorship. t 2.4.1 PercentDiversion Estimatesof percent diversionare basedon the annual estimatesof fish I entrapped in Units 2 and 3. Percent diversion was calculated as the number or I biomassof fish diverteddivided by the total number or biomassof fish entrapped

I 13 t I I times 100. Annual estimatesof total entrapmentwere used to calculatepercent diversion rather than concurrent 24 hr samples of impingement and diversion I becauseannual estimates include the heat treatmentcomponent of entrapmentas well as impingement and diversion. Estimatesof percent diversion differ slightly from thosecalculated by DeMartrn et a/. becausethey definedpercent diversion as I diversion divided by the sum of diversion plus impingement;they did not include heattreatment losses in the denominatorof the equation.Many largefish are found I in heat treatment samplesand to excludethem from estimatesof the total fish entrapped would result in an overestimateof percent diversion, particularly for biomass.

2.4.2.Percent Survivorship

Estimates of mortality from mechanical damage or physiological stress incurred during discharge through the FRS were based on the results of field experimentscontracted directly by Southern California Edison and conductedby researchersat OccidentalCollege. A summaryof the methodsis presentedhere; a more detailed descriptionis given in Love et al. (1987).

Fishesdischarged through the FRS were capturedin octagonal(about 3.7 m x 3.7 m) pens that were attached to the dischargepipes. Pen frames were constructedof PVC pipe andwalls were \f 4 in, knotless-meshnylon netting. Before the pen was attachedto the dischargepipe, any residentfish were flushed from the pipe. Once the net was attached,fish were dumpedfrom the FRS elevator basket into the return sluice channel and flushed down the dischargepipe into the pen. The fish usedin this experimenthad been entrappedin the plant for 24 hr or less.

T4 T I This is similar to normal operationssince fish are removedfrom the FRS collecting I bay at least oncea day. After receivingfish, experimentalpens were disconnected I from the dischargepipe, moved a shortdistance away and anchoredto the bottom. T To determine if mortality of fish in experimentalpens was the result of containingfish insidepens rather than transportthrough the FRS, control penswere t also established. Control pens were identical to experimentalpens but had detachablefyke-net wings designedto herd fish into the pen without damageor I stress. Control penswere set offshorein the vicinity of the dischargepipe 24 hrs t before the start of a control trial to capturecrepuscular and nocturnalcross-shelf migratorssuch as queenfish;therefore, some fish may havebeen in controlpens up T to 24 hrs longerthan in experimentalpens.

I Only one pen wasmonitored during eachexperimental or control trial. The I intent wasto monitor one experimentaland one control trial concurrentlybut trials were sometimesdisrupted by storms and other factors so that experimentaland t control trials often alternated over periods of several days to severalweeks. It is likely that variability in factors that vary with time (such as surge, temperature, I temporal variability in size distribution of fishes,etc.) were randomly distributed I amongexperimental and controltrials and shouldnot biasthe results. I Fisheswere held in pensand observedfor 96 hours. Fish were held for only 4 daysto minimize mortality from cageeffects. Short-termeffects resulting from the I FRS (such as physiologicalstress from scale loss or osmotic damage)will be detectedwithin 4 days,but long-termlethal effectswill not be detected. Thus,it is I likely that the resultsof this studyoverestimate percent survival. Dead fish were

I 15 I I I countedat the start of the experiment(fish that were deadwhen discharged)and daily thereafter. Although preliminary experimentsbegan in May 1983,only data I for the concurrent or alternating series of experimental and control trials I completedat SONGS during October 1983 to August 1985 are included in the survivorshipanalyses presented here. l

The number of speciesand of individualsof each speciespresent in a pen I varied among pens. Often, speciesthat were presentin experimentalpens were either absentfrom or rare in controlpens. This wasnot importantfor most species t that were not found in control pens because these species did not die in I experimentalpens. However,it was a problem for a few speciessuch as slough anchovyand topsmelt, that had relatively high mortality in experimentalpens and T no controls. I Speciescomposition and abundanceof fish in pensvaried because of random fluctuationsin the relative abundancesof speciesover time and becausethe intakes I and fyke netsdiffered in speciesselectivity. Species composition could be important I if predatoryspecies were trappedin penswith prey speciesbecause mortality could be the result of predation,not FRS or pen effects. There were high numbersof T predators (at least 15 fish, mostly yellowfin croaker) in 6 of 18 experimentalpens, and mortality in thesesix pens ranged from 22%oto 100Vofor all speciescombined. There is no direct evideirceto determineif predatorskilled the fish in thesepens becausethe appropriatedata (e.g. feeding observationsor stomachcontents of predators)were not collected. However,even if all the fish in thesepens were killed by predators,they would only representabout 8Vo of the total fish that died in all experimentalpens combined. There were manypens with high mortality and no

16 I I predators. Thus, predators may have killed some fish but it seems unlikely that t predation had an important impact on overall percent mortality. I To determine if mortality within experimentaland control pens was a T function of fish density,the observed96 hr mortality was regressedagainst the initial abundanceof fish in pens. Queenfishwere used in this testbecause they occurredin I all pens and had relatively high mortality. Mortality of queenfishwas regressed against initial abundanceof both queenfishand total fishes for experimental and I control pens separatelyand both pen typescombined. Resultsindicate that the I number of queenfishthat died in either experimentalor control pens was not relatedto fish densitiesin the pens(Table 4). I Sincethere was no apparentrelationship between mortality and fish density l in pens, the data were summed over all pens within each pen type, either experimentalor control. For eachtype of pen, total mortalirywas estimatedas the I initial number of fish minus the number alive after 4 days divided by the total I numberof fish initially presentin the pens. The numberof fish initially presentin experimentalpens included fish that were deadwhen discharged from the FRS. I Mortality in experimental pens was an estimate of FRS effects plus pen I effects,while mortality in the controlpens was an estimateof pen effectsonly. The t percent mortality causedby transport through the FRS was estimatedby subtracting control mortality from experimental mortality. Standard errors of the mean I mortality were also calculated and used to determine 95Vo confidence intervals. Detailsof the methodsused to estimatestandard errors are presentedin DeMartini I et al. (1987).

I T7 I I I Most speciesof fish entrappedat SONGS,did not occurin the survivorship e4periments,because they were not entrappedon those dayswhen experimental I trials were conducted. To include thesespecies in survivorshipestimates, species I were separatedinto size classesand the averagepercent mortality for speciesin different size classeswas estimated. This assumesthat there is a relationship I betweenaverage size of individualsof a speciesand the probability of survivingthe FRS. There are too few datato testthis assumptionfor differentspecies, although a t comparisonof percentmortality of large and small queenfishsuggest that mortality of the smallerfish is higher (Table 15). A speciesof fish was classifiedas either t small(<30 g), medium (30 - 199g), or large (> 200g) basedon the averageweight I of all individuals collected in quantitative impingement and diversion samplesat Units 2 and 3 (Table 8). Theseare the samesize-classes used to combinespecies t into largergroups for entrapmentestimates (see Section 3.L.2).

For some speciesmost of the individualsentrapped were juveniles. In the contextof this report the sizeclass of a speciesis basedon the averageweight of all t individualsimpinged or diverted,and doesnot necessarilyreflect the sizesof adults I in the population. For example,white croaker adults weight about 100 g (A. Ebeling,personal communication), but white croakeris classifiedas a small species T because most individuals entrapped were juveniles. Thus, while estimates of mortality for size classesare appropriate for the averageof individuals of species sizesentrapped at SONGS, the estimatescan not necessarilybe extrapolatedto adultsof the species.

Percentmortality for small specieswas calculatedas the weightedmean of i- mortality estimatesfor white croaker, walleye surfperch,white seaperchand r

18 I I I I queenfish. Other small specieswere not included becausethey did not have I adequate controls for pen effects. The controls were consideredparticularly I important for small species because mortality in control pens was not trivial. Northern anchovywere also excludedfrom estimatesfor small speciesbecause I mortalityin controlpens was much higher than in experimentalpens.

I The mortality estimatefor medium speciesis the weightedaverage of all species. Specieswith no controlswere includedbecause, without them, we could I not estimatemortality; the only medium speciesin control penswas blacksmithand I only one blacksmith occurred in experimentalpens. There was some mortality for medium speciesin experimentalpens and, since it is impossibleto determine l whether some deathswere causedby pen effectsrather than FRS effects,mortality t for the sizeclass may be overestimated. I The mortality estimatefor large speciesis also the weighted averagefor all large speciesin experimentalpens, even thosethat did not occur in control pens. I The lack of controlsfor some large speciesis not a problem becausevery few of t them died in the experimentalpens. I I I I

I 79 I I I 3. RESULTS I

Commonnames are usedfor speciesof fish throughoutthis report. Table is a list of commonand scientificnames for speciesthat were sampled.

3.1.Entrapment I 3.L.1.Entrapment samples t Entrapment of juvenile and adult fishesat Units 2 and 3 is estimatedas the I sum of fish that are impinged on travelling screens,killed during periodic heat treatments,or diverted to the Fish Return System(FRS). At Unit L, there is no FRS and entrapmentis estimatedas the number of fish impinged and killed in heat treatments. Most fishes are diverted to the FRS in the two new units. whereasin Unit L, most are impinged on travelling screens.

The total number and biomassof fish impingedin samplescollected from May 1983to August 1986at Units 2 and 3 are shownin Table 6; the total number and biomassof fish diverted to the FRS are listed in Table 7. Nearly 275,000fish (2.9 MT) were collected in impingement samplesand more than 7.2 million fish (10.8 MT) were collectedin diversionsamples during the 39 months. Overall, queenfishand northern anchovywere the most abundant fish in impingementand diversionsamples. Queenfish alone contributed about 307o of the number and48Vo of the biomassof fish in both typesof samples.

20 I I For more than 75Voof the speciesentrapped, individuals that were diverted I to the FRS were larger,on average,than thoseimpinged on travellingscreens. For I example,the mean weight of diverted queenfishwas 507ogreater than the mean weight of thoseimpinged (Tables 6 and 7, Figure 4). One exceptionwas northern I anchory, which was smaller, on average, in diversion samples than in either impingementor heat treatmentsamples (Tables 6 and 7, Figure 5). For northern I anchovy,the size differencemay have been due to the different methodsused to collectthe samples.Impingement and heat treatmentsamples were collectedfrom I the travelling screens. Many small anchovywere probably lost from the samples T because they were extruded through the 3/8"-mesh screens under fast-flow conditions. Therefore, the mean weight of northern anchovy in impingement I samplesis undoubtedlyoverestimated. In contrast,diversion samples were taken with smallermesh nets as the fish weredumped from the FRS elevatorbucket and it T is muchless likely that smallfish werelost from the samples. t Over the 39-monthsampling period, about 215,000 fish (9.8 MT) were killed I in heat treatmentsat Units 2 and 3 and an additional 11,000fish (1.3 MT) were killed at Unit 1 (Tables9 and 10). At Units 2 and 3, two speciesof small fish, I queenfishand northern anchovy,were most abundantin heat treatmentsamples, but the speciesof large fish, including yellowfin croaker, sargo and zebra perch, I accountedfor most of the biomass. The latter 3 speciesand spotfin croaker, another large fish, also representedabout 60Voof the biomassin heat treatment I samplesin Unit 1. I The averageweight per fish was greaterin heat treatmentsamples than in I impingementor diversionsamples for some species,particularly those that were

I 21, I I I abundant( > 100 individuals)in heat treatments(Tables 6, 7 and 9). The pattern was consistentfor two-thirds of the abundantspecies. For example,the mean I weightof white croakerin heat treatmentswas almost3 times the mean weight in diversionsamples and 5 timesthe meanin impingementsamples (Tables 6,7 and9, Figure 6). The mean weights of the 3 most abundant large species,yellowfin t croaker,sargo and zebraperch, were alsogreatest in heat treatments.Two of the exceptionswere northern anchovyand queenfish,both small species,which were I larger in impingementsamples than in heat treatments;queenfish were also larger in diversionsamples (Tables 6, 7 and 9). There is someindication that, in Unit 1, fish killed in heat treatmentsalso tended to be larger that those impinged on travelling screens(Figure 7).

3.L.2.Annual estimatesof entrapment

Annual entrapmentat Unit 1 and the new units was estimatedfor 77 species, all other speciescombined, and total fish (Table 11). The 17 specieswere chosen becauseof their abundancein samplesor importanceas commercialor sport fish species;together they representmore than 99%oof the fish entrapped at SONGS. Estimatesfor all speciesin Units 2 and 3, and all speciesexcept queenfish, northern '1-., anchovy and white croaker in Unit were calculated from quantitative impingement,diversion and heat treatment samplescollected from May 1983 throughAugust 1986.Annual entrapmentof queenfish,northern anchovy and white croakerin Unit 1 was estimatedfrom annual estimatesfor Units 2 and 3 (described in detail in Section2.3.2. and AppendixA).

22 t t Over the 39-monthperiod from May 1983to August1986, SONGS Units 1, 2 I and 3 togetherentrapped an averageof almost6 million fish (41.1 MT) per year I (Table 11). Fish entrappedat Unit 1 comprised5% of the total numberand l\Vo of the biomass(4.2 MT) and fish at Units 2 and3 comprised95Vo and 907o (36.9 MT) I of the number and biomass,respectively. Queenfish, northern anchovyand white croakerwere the most abundantspecies entrapped (Table 11). At Units 2 and 3, t queenfishrepresented 20Vo of the annual entrapmentby number and 39Voby weight. In contrast,northern anchovy accounted for 75Voof the individualsbut only I 13Voof. the biomassentrapped. White croakercomprised about 27o of both number I and biomass. I Specieswere classifiedas large,medium or small basedon the averagebody weightof fishescollected in the impingementand diversionsamples in Units 2 and3 T (Table 8). More than 90 speciesof fish wereentrapped at SONGS(Table 5). Since we cannot possiblydiscuss each species separately we usethis sizeclassification as a I convenientmethod for combiningspecies into largergroups. t Overall,most of the fish entrappedin Units 2 and,3were small species;they T represented56Vo of the biomassentrapped. Medium and large speciesaccounted for 73Vo and 3L7o of the biomassentrapped, respectively. The proportion of I entrapmentthat was small specieswas even higher if calculationswere basedon I abundance.Small species represented more than 987oof thoseentrapped; medium and large specieseach accounted for lessthan L%o. I Annual estimates of the three components of entrapment, heat treatment, I impinged and diverted at Units 2 and 3 are shown in Tables 12 and 13. Estimates t 23 I t I for numberand biomassof small,medium and largespecies were calculated by first dividing the "all other speciescombined" group into the 3 size classesand then I summingover all specieswithin sizeclasses. I About 66,000fish (3 MT), were killed in heat treatmentsin Units 2 and 3 I eachyear; this representsIVo by number and 8Voby weight of the total entrapment (Tables12 and 13). For most species,heat treatmentskilled a smallpercentage of I the fish entrapped. However,for 3 largespecies, spotfin croaker, barred sand bass andyellowfin croaker, heat treatment losses represented 47Vo,35Vo and25Vo of the I total biomassentrapped, respectively. Overall, large species represented 86Vo of the I biomassbut only 1,1.Voof the number killed in heat treatmentseach year. In contrast, small speciesaccounted for 87Vo of the number but only 1.|Vo of. the I biomass. I Fish impingedon travellingscreens comprised 14Vo (about 794,000)of the numberand20Vo (7.2 iN..{T) of the biomassof fish entrappedin Units 2 and3 (Tables I 12 and 13). In general,individuals of smallspecies were more likely to be impinged I in travelling screensthan individuals of medium or large species. Overall, small speciescomprised 62Vo of the biomassand 98%oof the number of fish impinged I annually. Medium speciesaccounted for 22Voby biomassand aboutZVoby number and largespecies represented only l6Voby biomassand lessthan lVo by number.

Most fish entrappedin the new units were diverted to the Fish Return System(FRS) and returnedto the ocean.The diversioncomponent comprised 85Vo (about4,740,000) of the numberand 72Vo (26.6 MT) of the biomassentrapped. The FRS is discussedin more detail below. I

24 I I T

I 3.2.Fish Return System

I 3.2.1.Percent diversion I Estimatesof percent diversion were based on annual estimatesof fish t entrappedin Units 2 and 3. Since annual entrapmentwas estimatedfor only 17 t species,percent diversion was also estimated for only thesespecies. Percentdiversion estimates for individualspecies ranged from 41,Voto 94%o I of the number (Table 12) and from 49Voto 91.Voof the biomass(Table 13) of fish I entrappedin Units 2 and3. At least80Vo of the entrappedbiomass was diverted for 7 of 17 species,For more than half of the species,percent diversion of biomasswas I greaterthan percentdiversion for number becauselarger individuals,on average, were diverted through the FRS (Table t3). For example,percent diversion of l queenfish,the secondmost abundantspecies, was 78Vofor biomassand TLVofor I number becausethe averageweight of diverted fish was about one-third greater than the weight of those impingedor killed in heat treatments. In contrast,for 2 I large species,yellowfin croakerand spotfincroaker, percent diversion was greater for numberthat for biomassbecause larser individualswere lost in heat trearments. I Percentdiversion estimates for the size classesare shownin Tables 12 and I L3. Overall,85Vo of the number and77Vo of the biomassof smallspecies (including I northernanchovy) were divertedto the FRS. Percentdiversion of medium species was68Vo for numberand 667ofor biomassand diversionof large specieswas 74Vo I for numberand 67Vof.or biomass. I

I 25 I t

3.2.2.Percent survivorship I I Survivorshipof fish divertedto the FRS was estimatedfrom resultsof field trials conducted off SONGS from October 1983 to August 1985. Eighteen l experimentaland nine control trials were completedduring this period. Resultsof all trials are listed in Table 14; speciesare categorizedby meanbody weight (see I Methodsfor details;size classes are shownin Table 8). A total of 28 speciesof fish I occurredin experimentalpens but only 12 of them were found in control pens. For 60Voof the species,fewer than 10 individualswere found in all experimentalpens I combined. Thesesample sizes were too low to estimatepercent mortality for the individualspecies with any confidenceand the resultswere sunmed for each size T class("other species" in Table 14). I Somespecies that wererelatively abundant in experimentalpens were rare in I controlpens. Sincecontrol trials were used to factorout the effectof containingfish insidepens, mortality of speciesthat died in experimentalpens but had no control I could be due to either transportor pen effects. Sloughanchovy were absentfrom control pens, but high mortality could be attributed to the FRS since97%o of the T individualswere alreadydead when discharged from the return pipe. t The percentsurvivorship estimates derived from this study must be viewed I with caution. First, while more than 62 speciesof fish were diverted to the FRS (Table 7), only 28 specieswere observedduring the study and only 11 of these T occurred in number high enough to estimate species-specificmortality; in experimentalpens the other specieswere grouped. In addition,the lack of adequate controlsfor pen effectsfor most speciesmeant that percentmortality was estimated I

26 I t T I with confidence for only 4 species. Finally, since trials lasted only 4 days,long-term

I prospects of mortality due to FRS effects were not assessed. As a result survival t may be overestimated. We include these estimates in this report becausethis was the only study of mortality effects of the FRS. I The three most abundantspecies entrapped at SONGS,queenfish, northern I anchovyand white croaker,were well representedin experimentaltrials and also occurredin control trials (Table 14). Mortality of queenfishin experimentalpens I was52Vo, but since20Vo of the individualsin controlpens also died, the estimated t mortality due to stressassociated with the FRS was 327a. Queenfishwere in all experimentalpens; although half of the total number occurred in only 2 pens, t another5 penshad at least L00individuals. Queenfishwere also in all the control pens. The number of queenfishin control penswas an order of magnitudelower I than the number in experimentalpens, but there were at least L5 individualsin I more than half of the control pens. Fifty-two percent of the white croaker in experimentalpens died (Table 14). White croaker occurredin 10 experimental I pens but 80Voof them were in only 2 pens. No fish died in control pens, but, becausethe samplesize was small, this may not be an adequatetest for pen effects, t and mortality due to the FRS may be somewhatoverestimated.

T Only 3Voof the northernanchovy in experimentalpens died, but 85Vodied in I the controls(Table 14). The controlestimate was based on 108fish in only one pen and the fish may havebeen killed by somerandom factor that wasunrelated to the I effectsassociated with holding fish inside a pen. Sincethe estimatefor northern anchovy is based on more than 5,500 fish in L0 experimentalpens, percent I survivorshipwas, most likely, very high for this species.

T 27 t I I Percent mortality of 4 other species,walleye surfperch,white seaperch, deepbodyanchovy and Pacific pompano,was also very low. Estimatesfor the latter I 3 specieslacked adequate controls, but this wasprobably not importantbecause few t fish died. Sloughanchovy had the highestmortality in experimentalpens; all fish died (Table 14). Although there was no control,93Vo of the fish were deadwhen I discharged. Therefore, it is clear that slough anchory do not survive transport throughthe FRS. This is not unexpectedbecause slough anchovy are small,fragile I fish that losescales easilv. t Only two medium species,salema and topsmelt,occurred in relativelyhigh T numbersin experimentalpens, and neither was found in control pens (Table 1a). None of the 122 salemadied, so the lack of controlswas not important. Mortality of I topsmelt was 30Vo, but without a control, mortality cannot be unquestionably attributed to the effects of the FRS; mortality of topsmelt causedby FRS effects I could rangefrom a only few percentup to 30Vo. t The only large speciesthat occurred in high numbers in experimentalpens I was yellowfin croaker and almost all of them survived. A total of L5 yellowfin croakeroccurred in 3 controlpens and nonedied. t

The averagepercent survivorship for all small specieswas 68Vo (Table 16). I It was estimated as the weighted averageof all small specieswith controls (queenfish,white croaker,walleye surfperch, white seabass);northern anchory were not includedbecause the controlwas not adequate.Survivorship for smallspecies is a reflection of survivorshipof queenfishbecause it was by far the most abundant small speciesin the experiment. This is consistentwith entrapmentresults; if

28 I

northern anchovy are excluded, queenfish comprised more than 85Vo of the I abundanceof small speciesentrapped. Survivorship of medium species(calculated t as the weighted averageof all medium speciesin experimentalpens) was 77Vo (Table 16). The estimatewas basedprimarily on survivorshipof topsmelt,which t comprisedmore thanT1Voof the fish in the mediumsize class; it was also the only mediumspecies that died. Therewere no topsmeltin controlpens, so mortality due t to pens effectscould not be estimated,and survivorshipmay be underestimated. Therefore,77Vo is probably an underestimateof survivorshipfor medium species; I survivorshipcould actually be as high as 95Vo. Very few fish in the large size class I died and survivorshipfor largespecies was close to 100Vo(Table 17). t It was not possibleto estimatepercent survivorship based on the biomassof fish that survive transport through the FRS becausefish were not weighed. t Therefore, the estimatesbased on number (describedabove) are also the only availableestimates for biomass.Irngth datafor two speciessuggest that largerfish t havea higherprobability of survivingthan smallerfish. Mortality in experimental I and control penswas3TVo for small (<100 mm SL) queenfishand only 27Vofor large ( > 100mm SL) queenfish(Table 15). A comparisonof the size distributions I of white croakerthat lived with thosethat died showsthat a higherproportion of the largerindividuals survived (Figure 5). Thus,estimates of percentsurvivorship based T on numberof fish probablyunderestimate percent survivorship based on biomass. t 3.2.3.Efficiency of the Fish Return System

I The efficiencyof the Fish Return System(FRS) is defined as the percentof I the fish entrappedin SONGSUnits 2 and 3 that are returned to the oceanalive. t 29 t t 't,

The efficiencyof the FRS was estimatedfor 9 speciesand three sizeclasses of fish. Specieswere includedif percentsurvivorship estimates for FRS effectswere based t on at least 1,0fish (Table 1,4)and if percent diversionhad been estimated. The T percentefficienry estimates reported here are maximumestimates because they do not includemortality from FRS effectswhich are lethal more than 4 daysafter fish t are discharged. I Efficiencyof the FRS rangedfrom a low of about25Vo f.or white croakerto a high of about 90Vo for walleye surfperch and salema (Table 16). Efficiency for t northernanchovy was relatively high: 87Vo of the numberand 76Voofthe biomassof I entrappedfish were return to the oceanand survived.Efficienry for queenfishwas lower: 48Vofor number and53Vo for biomass. The FRS was most efficient for large t species;percent efficiency wasT4Vo for numberand 6TVoforbiomass. On average, about 50Vo of fish in the medium and small (minus anchovy) size classeswere I returned and survived(Table 16). I 3.3.Estimated losses at SONGS T

A large proportion of the fish entrappedin Units 2 and3 were divertedto I the FRS. Estimatesof the overall percent efficiencyof the FRS, in conjunctionwith estimatesof lossesfrom impingementand heat treatments,can be usedto estimate I the numberand biomassof fish that werekilled eachvear at SONGS. I Overall,5.6 million fish (36.9MT) were entrappedeach year at Units 2 and I 3. Almost 860,000fish (10.2MT) were impingedor killed in heat treatments;the remaining4.7 million tish (26.7MT) werediverted to the FRS. Eight percentof the I

30 I t t I number(approximately 411,000) or about 78Voof the biomass(4.8 MT) of diverted I fish were killed during or shortly after dischargeas a result of injuries incurred in I the FRS. Therefore,the. total numberof fish killed eachyear at Units 2 and3 was ,l approximately1..27 million (15 MT). The FRS successfullyreturned 4.33 million fish (21.9 MT) representing77%o of the fish (59Voof the biomass)entrapped at T Units2and3. More than98%oof the numberof fish entrappedat Units 2 and3 were small I species;medium and large speciesaccounted for about 1.Voand 0.5Vo, respectively. I The two most abundantsmall species,northern anchovy and queenfish,accounted fot 75Vo and 20%oof the total fish entrapped,but since they were small, they l comprised only 13Voand 39Vo,respectively, of the biomass. Small, medium and largespecies comprised 56Vo, I3Vo, and 3IVo of the biomassentrapped, respectively. I Smallspecies were sucha dominantcomponent of the fish entrappedat Units 2 and I 3 that they accountedfor almost 98Voof the fish that survivedeven though they had the lowestprobability of survivingFRS transport. Smallspecies represente d 54Voof T the biomasssuccessfully returned while medium and large speciescomprised llVo t and3 5 Vo, respectively. During May 1983to August 1986,about 272,000juvenile and adult fish (4.2 I MT) were entrappedeach year at Unit 1; theyall died. Approximately t.27 million T (15 MT) of the 5.60 million juvenile and adult fish entrappedannually ar Units 2 and 3 were killed. Therefore,total annuallosses at SONGSwere 1.54million fish t (19.2 MT). This represents26Vo of" the number and 477oof the biomassof fish I entrappedannually at SONGSduring this period.

T 31 l I

4. DISCUSSION t I 4.1.Entrapment and Lossesat SONGS t During the 39-monthperiod from May 1983 to August 1986,almost six '1.,2 million fish weighing41.1 MT were entrappedannually at SONGSUnits and,3. I The estimatesof annual entrapmentare too low becausesome small fish passed I throughthe travellingscreens in all three units and could not be sampled. While the abundanceof fish may be substantiallyunderestimated by the loss of these t individuals,the effect on estimatesof biomassis smallerbecause the fish are small. I Entrapmentof small speciesat Units 2 and 3 is a better approximationof actualentrapment than estimatesfrom Unit 1 becausemore smallfish were trapped t on the small-meshscreens in the new units. Consequently,entrapment at Unit 1 for t northern anchovy,queenfish and white croaker,the 3 most abundantspecies, was estimated from entrapment at the new units. However, this method still T underestimatesentrapment at Unit 1 becausemany small fish are lost from Units 2 ,[ and 3 (for example,northern anchovy up to 90 mm can passthrough the screensin the new units) and becauseof the uncertaintyin the estimate of the ratio of entrapmentat Unit L and the newunits. I l 4.2.Temporal comparisons of the magnitudeof entrapment T Annual estimatesof entrapmentwere basedon samplestaken over a 39- month period and incorporatedshort-term (e.g. seasonal) fluctuations in the density t of fish near SONGS. However, fish densitiescan fluctuate over much longer I

32 t I I t periods(e.g. years) due to factorssuch as successiveyears of poor recruitmentor I long-termchanges in water temperature.

I To predict entrapmentin the future at SONGS,we must considerpossible I long-termchanges in local fish densities. One method is to compareentrapment during an earlier period, March L976to December 1979,with entrapmentduring t May 1983to August 1986.Units 2 and 3 were not operationaluntil 1983,but Unit 1 I was operating during both periods. During 7976-1979,the average annual 1 entrapment at Unit 1 was 445,000fish, weighing 76.7MT (DeMartini and Larson I 1980). Unit 1 pumpedat an averageflow level of 83Voduring this period. During 1983-1986,Unit 1 entrapped272,000 fish weighing4.2 MT annuallywhile operating t at 567oof maximumflow. When the 1983-1986biomass estimate is adjustedto the 1976-1979pumping level (multiply 1983-1986estimate by 0.83 / 0.56),the annual I entrapmentfor 1983-1986becomes 6.2 MT; this is only 377o of the 1976-1979 entrapmentat Unit 1. One possibleexplanation for the much lower entrapmentat t Unit t in 1983-1986is the broadscalereduction of nearshorefish during 1982-1985 I inducedby El Nino (DeMartini et al. 1987).

I Since SONGS Units 2 and 3 were not operationaluntil the early 1980's, entrapment cannot be estimateddirectly for a period of higher abundanceof I nearshorefish suchas occurredin 1976-1979.Since entrapment at SONGSdepends I to a large extent on the nearshoreabundance of fish, it is reasonableto estimate entrapmentat Units 2 and 3 during periods of greater nearshoreabundance based I on the differencein entrapmentat Unit 1 between1976-L979 and 1983-1986.If the nearshoreabundance of fish were at 1976-7979levels, then SONGSUnits L,2, and

t 3 togethermight entrapmore than 110MT of fish eachyear (41,.2MT f .37,at I I I t about 75% flow). If overall efficiencyof the FRS remainedat the samelevel as 1983-1986(47Vo for biomass),then 52 MT of fish wouldbe killed eachyear. T

4.3.Fish Return System I

4.3.1". Percent diversion t T The majority of fish entrappedat SONGSUnits 2 and3 are divertedto the FRS; averagepercent diversion for all speciesentrapped was 85Vo for numberand I 72Vofor biomass.There was, however, a greatrange in the percentdiversion among species that reflects differences in morphological characteristicsof species, t particularly those characteristicsthat influence swimming speed. As an extreme example,pipefish are srnall,pencil-like fish that swim feebly and none of more than I L00entrapped individuals were diverted. T

There was some influence of body size on successfuldiversion for the I typically "fish-like" (subcarangiformand carangiform)swimmers that comprisedthe majorityof fish entrapped.In general,for smallspecies, smaller fish were impinged I and larger ones,which were presumablystronger swimmers, were diverted. The major exceptionto this patternwas northernanchovy, but the observedlarger size t of impinged anchovymay be a samplingartifact. Northern anchoyyup to about 90 I mm in length can passthrough the screensin Units 2 and 3 and, therefore,small individualsmay. be underrepresentedin impingementestimates. I I If body sizeis the most importantfactor influencingdiversion for all species, t then percentdiversion should increase with body-sizeand diversionof largespecies I

34 I I I I shouldbe highest. This pattern doesoccur if diversionestimates are basedon the

I numbers of fish entrapped;large speciesare most successfullydiverted QaVo). I When diversionis basedon biomass,however, diversion of smallspecies is greatest. This differencereflects the importanceof heat treatment lossesfor some large I species.Heat treatmentlosses accounted for 237oof the biomassof large species entrappedcompared to only ZVofor smalland medium-bodiesspecies. On average, I larger individualsof large speciestended to remain in screenwellsand were killed during heat treatments.In particular,yellowfin croaker, which accountedfor about I 35Voof the biomassof all largespecies, were 50Volargerin heat treatmentssamples I than in diversionsamples. I 4.3.2.Survivorship I Survivorshipof fish divertedto the FRS was determinedfrom the resultsof field experiments.Estimates of percentsurvivorship for most speciesare unreliable t becauseof poor replicationand lack of controls. However,estimates for one of the most abundantspecies, queenfish, is probably closeto actual survivorshipbecause it t is based on large sample sizes and has an adequate control for pen effects. I Although they lack controls, estimatesfor northern anchovyand the large species classificationmay also be close to actual survivorshipsince few fish died in t experimentalpens.

I The estimate of survivorshipfor small speciesexcluding northern anchovy was based almost entirely on survivorshipof queenfish. This reflects the relative I importanceof queenfishin diversionsamples; without northernanchovy, queenfish I accountedfor almost 90Voof the total diversionof small species. We did not

I 35 I I I include northern anchovyin estimatesfor small speciesbecause of the problems with the control. If northern anchovyare includedin the estimateof survivorship I for smallspecies, survivorship increases from 68Voto 9tVo. I The estimateof survivorshipfor medium speciesis unreliable. There were I no controlsfor mortality due to pen effectsfor any of the abundantmedium species, so actual survivorshipcould range from 70Voto L00Vo.The uncertainty about this t estimatehas little effect on the estimateof total lossesof fish at SONGSbecause mediumspecies comprised only 1,Voof the number and 73Voof the biomassof fish I entrapped. Estimatedsurvivorship for large speciesis probably reliable because I only 4 of more than 400largefish died in the study. I Another sourceof mortality for dischargedfish that hasnot beenconsidered explicitlyis an increasein the risk of predation. When fish are dischargedfrom the I FRS they may be weakenedand disoriented. They may be more vulnerableto predatorsduring the recoveryperiod than they would be normallyso that mortality I from predationwould be higher than normal. Predatorssuch as halibut and kelp I bassoccur near the FRS exit, and they probably prey on fish as they are discharged from the pipe. However,predation by thesespecies probably occurs at a relatively I low rate. Predationby schoolsof predatoryfish is likely to be more serious. For example,on severaloccasions, Chub mackerelwere seeneating all of the anchovy I dischargedfrom a return conduit (J. Stein,formerly of OccidentalCollege, pers. I comm. to E. DeMartini), and K. HerbinsonQters. comrn.) saw heary predationbe jack mackerel and barracudaon one of six dives at the FRS dischargepipe. In I addition,the local abundanceof predatorscould be higherthan normal if they are attractedto the dischargedfish or the pipe structures. I

36 t I I I We have no data on predationrates near the dischargeconduit at SONGS I and any estimate of mortality due to predation would be highly subjective. I Furthermore,we know of no studiesof predation on fish dischargedfrom other marinefish diversionsystems. Only a few studieson the survivalof fish havebeen I publishedin the last ten years(as indicated by a computerizedDIALOG searchfor the years 1977-1989).Edwards et al. (1983) showedthat severalspecies of fish t residewithin screenwellsand studiedpredation in the intakes,but did not examine predationafter fish were discharged.Other studiesclaiming low mortality of fish I dischargedfrom fish diversionsystems (Taft and Mussalli 7978),along with studies I that have found higher fish mortalities (Lawler et al. 1982b),give no information aboutmortality from predationonce fish are dischargedfrom the system. I Although there are no relevant data available,it seems likely that the t probability of being killed by a predator shortly after dischargedepends on size; small fish are probablyat greaterrisk than large fish. Consequently,the effectsof I predationcould potentially increase estimates of the numberof fish lost at SONGS I but would have a much smallerimpact on biomass. For example,if 25Voof the northern anchovy returned by the FRS were eaten by predators, the estimated I numberof fish killed at SONGSeach year would increaseby nearlyone million fish (an increaseof 78Vo),but the additionalweight of the fish killed would be only 1.3 I MT (an increaseof only7%). I I I I JI I I I This page intentionally left blank. I I I t I I I I I I I I I I I I t I I 5.0 REFERENCES I DeMartini, E.E. and R.J. Larson. 1980. Predictedeffects of the operationsof I SONGSUnits I,2, and3 on the fish faunaof the SanOnofre region. Report I submittedto the Marine ReviewCommittee, Inc., May 1980. I DeMartini, E. E. and UCSB Staff. 1986. Preliminarystatistical comparisons of baselineand operationalsamples for otter trawl and lampara seinetasks and I estimationand comparisonsof entrapmentand mortalityof fishesat SONGS Units 1,,2,and 3: Annual report of the UCSB Fish StudyProject. Report I submittedto the Marine ReviewCommittee, fnc., June 1986. I DeMartini, E.E. and UCSB Staff. 1987. The effects of operations of the San I Onofre Nuclear GeneratingStation on fish. Final Report submittedto the Marine ReviewCommittee. Inc.. I December1987. Edwards,S.J., J. Dembeck,T.E. Peaseand M.J. Skelly. 1983. Evaluationof fish I residencywithin an angledscreen diversion system. In: Proceedingsof the I 26th Conferenceon Great Lakes Research. May L983,State Universityof New York at Oswego.pp.21. I Electric Power ResearchInstitute (EPRI). 1984. Advancedintake technologies I study. ElectricPower Research Institute Report CS-3644,September. 1984.

I I-awler, Matuslry and Skelly Engineers. 1982a. Intake technologyreview. Report t submittedto SouthernCalifornia Edison Co.. R & D Series82-RD-164.

I 39 I I-awler, Matusky and Skelly Engineers. 1982b. Evaluation of the angledscreen diversionsystem at OswegoSteam Station Unit 6. Interim report to Niagara MohawkPower Corporation, Syracuse.

Love, M.S., M. Sandhu,J. Stein, K.T. Herbinson,R.H. Moore, M. Mullin, J.S. Stephens,Jr. 1987. An analysisof fish diversionefficiency and survivorship at the San Onofre Nuclear GeneratingStation fish return system. Report submittedto the Marine ReviewCommittee, Inc., January L987.

Margraff,F.J., D.M. Chaseand K. Strawn. 1985. Intake screensfor samplingfish populations;the size-selectivityproblem. N. Am. J. Fish. Manage. 5: 210- 2t3.

Schuler,V.J. and L.E. Larson. 7975. Improvedfish protectionat intake systems. In: J. Env. Eng. Div., ASCE,Vol 101,No. EE6, Proc.Pap.L1756, December 1975.pp.897-910.

Sharma,R.K. 1978. Perspectiveson fish impingement. In: Fourth National Workshop on Entrapment and Impingement.Ecological Analysts. Chicago, IL. Jensen,L.D.ed. pp 351-356.

Taft, E.P. and Y.G. Mussalli. 1978. Fish diversionand transportationsystem for powerplant application.Fisheries 3(3): 2-5.

40 I I Thomas,G.L., R.E. Thorne, W.C. Acker, T.B. Stablesand A.S. Kolok. 1980. The I effectivenessof a velocity cap and decreasedflow in reducing fish I entrapment.University of WashingtonFisheries Research Institute. Report to SouthernCalifornia Edison. t Turnpenny,A.W.H. 1981.An analysisof meshsizes required for screeningfishes at I waterintakes. Estuaries4: 363-368.

I Weight,R.H. 1958. Oceancooling water systemsfor 800 MW power station. J. I PowerDiv. Proc.Amer. Soc.Civ. Engr. 188822. I I I I I I I I I

I 41, t I I t I I I I I This pageintentionally left blank. I t I I I I I I I t I 6.0 TABLES Table 1 page1 ofS

List of dates (X) of quantitative entrapment collections at SONGS Unit 1, 2, or 3 during the 39-mo period from May 1983through August 1986. Collections at Unit I are quantitative impingement samples and at Units 2 and 3 include both quantitative impingement and diversion samples.

UNrf 1 ur{rr2 UNrI3

25 MAY3 X O1-JUN 3 X 1OAUG3 X 24 AUG3 X 21 SEP3 X 05 Ocr 3 X I 11oCT 3 X 12 OCT 3 X L9 OCT 3 X I 30 NOV 83 X

O4JAN84 X x 05 JAN 84 X 11JAN 84 x L8 JAN 84 X 14 FEB 84 X 15 FEB 84 X 21 FEB 84 X 22FEB 84 X 29FEB84 X 06 MAR 84 X OTMAR 84 X 20 MAR 84 X X 28 MAR 84 X 17APR 84 X 18APR 84 X X I 24APR 84 X X 25 APR 84 x X 22MAY 84 X 30 MAY 84 X I 06 JUN 84 X X L2JUN 84 X 13JUN 84 X 18JUL 84 x O1AUG84 X 14AUG 84 x X 1,5AUG 84 X ?2AUG84 X X 05 SEP84 X X I 44 I I I Table 1 I page2 of5 I DATE UNrr 1 UNIT2 UNIT3 19SEP 84 X 03ocr 84 X 09Ocr 84 X X I 10 OcT 84 X X 16 OCT 84 X 17 oCT 84 x X I 24 OCf 84 X 30ocr 84 X 07 NOV 84 X 14 NOV 84 X I 20 NOV 84 X 11DEC84 x 18 DEC 84 X I 19DEC 84 X 26DE,C84 X I N DF,C84 x X 03 JAN 85 X 09 JAN 85 X X 16 JAN 85 X X I 23 JAN 85 X X 29 JAN 85 X 30 JAN 85 X X I 06 MAR 85 X X 13 MAR 85 X 20 MAR 85 X X 26 MAR 85 X I 27 MAR 85 X X OzAPR85 x X O3APR85 X X I 09APR 85 X 1OAPR85 X X 1,6APR85 X X X 17APR 85 X X X I 23APR 85 X X X 24 APR 85 X X X 25 APR 85 X X X I 07 MAY 85 X X 08 MAY 85 X X 15 MAY 85 X x I 21MAY 85 X 22 MAY 85 X 29 MAY 85 X 30 MAY 85 X I 04 JUN 85 X X X 05JUN 85 X X I I 45 t I Table 1 page3 of5 I DarB UNrf 1 UIIT2 UNrr3 I 11JUN85 X 18JUN 85 X 25 JUN 85 X X 26 JUN 85 X X X I 02JUL 85 X X 03 JUL 85 X 09 JUL 85 X I 10JUL 85 X 16JUL 85 X X X 17JUL 85 x x 23 JUL 85 X X I 24JUL85 X X 30 JUL 85 X x 31JUL 85 X X X I 06AUG 85 X 14AUG 85 X X 15AUG 85 X I 2OAUG85 X X 21AUG 85 X X 27AUG 85 X X 28 AUG 85 X X I 04 SEP85 X X X 05 SEP 85 X 10SEP 85 X I 12 SEP85 X X 17SEP 85 X X X 18SEP 85 X 24 SEP 85 X I 01 OcT 85 X 02 OcT 85 x 08 ocT 85 X I 09 ocr 85 X 15 oCT 85 X X 16 oCT 85 X 22 OCT 85 X I 29 OCT 85 X 05 NOV 85 X X 13NOV 85 X t 19NOV 85 X 24 DEC 85 X 31DEC85 X I I t 46 I I I Table 1 t page4 of5 Danr I UNrr 1 UNrr2 UNrr3 07 JAN 86 X 08 JAN 86 X 21JAN 86 X T 22JAN 86 x x 28 JAN 86 X X DJAN 86 X X I 04 FEB 86 X 05 FEB 86 X 19 FEB 86 X 20 FEB 86 X I 25 FEB 86 X 26 FEB 85 X 04 MAR 86 X I 05 MAR 86 X 11MAR 86 X 12MAR 86 X I 25MAR 86 X % MAR 86 X Ol APR 86 X 02 APR 86 x I 08 APR 86 X O9APR86 X 15 APR 86 X I 16APR 86 x 22 APR 86 X 23 APR 86 X 29APR 86 X I 30 APR 86 X 07 MAY 86 X 20 MAY 86 X I 21MAY 86 X 28 MAY 86 X 29 MAY 86 X 03 JUN 86 X I 04 JUN 86 x 10JUN 86 X X 11JUN86 X X I 17JUN 86 x 18JUN 86 X 24 JUN 86 X I 25JUN 86 X Ol JUL 86 X X X 02 JUL 86 X X 08 JUL 86 X I 15JUL 86 X t I 47 Table 1 page5 of5

UNrI 1 UNIT2 UMT3

16JUL 86 X 22TUL86 X X 23 JUL86 X X O6AUG86 X 12AUG 86 X 19AUG 86 X x 20 AUG 86 X 26AUG 86 X x X 27 AVG86 X I I Table 2

List of dates on which heat treatments occured at SONGS Units 1, 2, or 3 during May 1983 - August 1"986.

T DATE UNrr 1 UNrf2 Ui\rrr3

30 MAY 83 X I MJUN 83 X 20 AUG 83 X 01 ocT 83 X 17 OCT 83 X 05 NOV 83 X 14 NOV 83 X 21 DEC 83 X

17 MAR 84 X 05 APR 84 X I 28APR 84 X 23 MAY 84 X r.4JUL 84 X t 29 JUL8r'. X 25 AUG 84 X 15 SEP 84 X 06 ocT 84 I 20 OcT 84 X

25 JAN 85 X I 08 MAR 85 X 21MAR 85 04 MAY 85 13MAY 85 t 26 MAY 85 22 JUN 85 30 JUN 85 I 12JUL 85 X 03 AUG 85 X 10AUG 85 X 07 SEP85 X I 14 SEP85 X 03 NOV 85 X I 22DEC85 09 FEB 86 X r.6JUN 86 X 06 JUL 86 X I O2AUG86 x 24 AUG 86 x I 31AUG 86 X I t 49 Table 3 pageI of2

Number of full flow operational days per month for SONGS Units 1, 2, andl3 for the period May 1983 - August 1986. Calculations are based on total monthly flow rate daily normal-flow rate. The daily llow rate for each unit is: I Unit 1: 1.7x 106m3/dy Unit 2: 4.5x 106m3/dy Unit 3: 4.5x 106m3 /dy I

Dans, UNrr 1 UNIT2 UNrr3 UNrrs2 & 3 t

MAY 83 9.50 25.L5 9.65 34.80 JUN 83 tt.52 22.39 t4.26 %.6s I JUL 83 6.77 30.99 1_5.08 /16.08 AUG 83 15.I7 29.85 L5.49 45.35 SEP83 9.88 30.00 L8.24 8.4 I OCT 83 L3.62 31.00 29.49 60.49 NOV 83 2L.68 30.00 29.99 59.99 DEC 83 21.58 L8.25 25.99 4.24 t JAN 84 24.88 2r.00 L2.99 33.99 FEB 84 23:X 19.25 4.89 24.13 MAR 84 2L.5r 30.75 ?6.99 57.74 APR 84 11.36 30.00 29.99 59.99 MAY84 7.4r 31.00 24.49 55.49 JUN 84 0.79 2L.50 2L.49 42.99 ruL 84 0.87 17.50 21.99 39.50 AUG 84 0.00 30.49 n.24 ffi.74 SEP84 0.32 30.00 29.99 59.99 OCT 84 23.0L 20.w ?3.49 48.49 NOV 84 29.96 0.00 14.99 1"4.99 DEC 84 30.95 0.00 29.W 29.00

JAN 85 29.68 3.25 28.00 3r.25 FEB 85 1.6.51 L2.00 14.00 26.00 MAR 85 27.9',7 2r.N 30.50 51.50 APR 85 29.86 23.50 29.75 53.25 I MAY 85 ?5.00 31.00 30.92 6r.92 JUN 85 29.78 30.00 30.00 60.00 JUL 85 29.5r 31.00 31..00 62.00 I AUG 85 24.86 3r.00 31.00 62.00 SEP85 2',1.69 30.00 r7.w 47.00 OCT 85 30.67 31.00 0.00 31.00 NOV 85 23.9L 19.77 4.42 20.?I T DEC 85 15.50 29.57 15.67 45.25 I I 50 I I I Table 3 T page2 of2 UNIT 1, UNrf2 2 I UNrr3 UNrrs & 3 JAN 86 4.86 30.82 ?5.22 57.05 FEB 86 0.00 28.00 25.30 53.30 MAR 86 0.00 L8.92 22.07 40.99 I APR 86 0.00 0.34 30.00 30.v '1.20 MAY86 2.68 31.00 33.68 JUN 86 17.72 n32 30.00 57.32 I JUL 86 23.83 30.74 29.46 60.20 AUG 86 ?4.23 30.65 28.68 59.33 I TOTAIS 67792 93r.70 914;74 L846.47 Total possiblenumber of full-pumpingdays for eachunit = 1,,218

I Percentof Full Pumpingfor period May 1"983- August 1-986:

Unit 1: 677.92/1218= 56Vo I Unit 2: 93L.70/Lzr8= 76Vo Unit 3: 9L4.75/LZI8= 75Vo l unirs 2 & 3: 1846.47/2436 = 76Vo I l I I I I I I t I

Table 4 I

Results of regressions of percent queenfish mortality vs. (A) initial abundance of queenlish or (B) initial abundance of total fishes in experimental, control and I pooled (experimental + control) pens in study of survivorship of lishes discharged from the FRS at SONGS Units 2 and 3. I (A) Queenfishmortality vs. Initial abundanceof queenfish. I p2 Slope I Experimental Pens 18 0.00 0.05 0.35 Control Pens 9 0.00 0.01 0.76 I Pooled Pens 27 0.00 0.00 0.98 (experimental + control) I I (B) Queentishmortality vs. Initial abundanceof total fish.

SLoPE 112 I

ExperimentalPens 18 0.00 0.01, 0.77 T Control Pens 9 0.00 0.05 0.55

PooledPens 27 0.00 0.01 0.58 T (experimental+ control) I I I t I I 52 t I

Table 5 I page1 of2

List of speciescollected in quantitative samples at SONGS Units 1, 2 and 3 for the I period May 1983 - August 1986. I CouuoNNavp SCIENTFICNAME

barred sand bass Paralabrm nebuliftr I barred surfperch Arnplti sti chus atgenteus basketweavecusk-eel Opltidiort scrippsae bat ray Myliobatis califomica black croaker Clrcilotrenn satunxum I black perch Erttbiotoca jacksorti blacksmith Cltrontis punctipirutis blenny spp. Hypsoblennius spp. I bocaccio Sebostespaucispinis brown rockfish Sebastesauictrlottts cabezon Scorpa eniclt tltys m armoratus Pacific barracuda Sphyraena atgentea I California butterfly ray GTmtrutranwnnorata California corbina M enticinluts urtdulatus California halibut P aral i chthys califomicus I California lizardfish Syrtodrtshtcioceps California moray Gyrttrtothoraxmordax California scorpionfi sh Scotpaena guttata California sheephead Semic o s sypht ts pttl cher l California tonguefish Sytrtplutrusaticauda thresher shark Alopias wtlpittrts crevice kelpfish Gibbortsia ntontereyensis I deepbody anchovy Anchoa compressa diamond turbot Hypsopsetta guffitlata Dover sole Microstomus paciftcus fantail sole Xystreurys liolepis I finescale triggerfish Balistes polylepis garibaldi Hypsypops rubicurtdus giant kelpfish H eterosticltus rostrafits I goby spp. Gobiidae spp. grass rockfish Sebqstesrastrelliger gray smoothhound Musteh$ califumiarc I California California grunion Leuresthes tenuis halfmoon Media luna califomiensis horn shark H etero dorttus fra ncisci hornyhead turbot Pleu ron i ch thys vertic ali s I jack mackerel Traclutrus rymmeticus jacksmelt A tlrcitnpsis califomiensis kelp bass Paralabrax clathratus I kelp perch Braclryistius frenatus northern anchovy Engraulis ntordax onespot fringehead N eoclirtrts tuinota tus opaleye Girella nigricans I Pacific angel shark Squatina califonica t Pacilic bonito Sarda cliliensis T 53 I

Table 5 page2 of2 I

CoMMONNAME SCIENIFIC NAME I

Pacificpompano Peprihts simillimus Pacificelectric ray Torpedo califunica I Pacifichalibut Hippoglossus stenolepis. Pacificherring Clupea harengus pallasr chubmackerel Scontberjaponicus I Pacificsanddab Cithaicltthys sordidus Pacificsardine Sordinops sagax Pacificstaghorn sculpin Leptocotttts amrafits pile perch Rhacocltilus vacca I pipefish Syngtathus spp. plainfin midshipman Poichthys notafits queenfish Seipltus polirus I rainbowseaperch Hypsurus caryi rock wrasse H ali clrcere s senic in cfiis rockfishspp. Sebastesspp. round herring Etnuneus teres I round stingray Urolopltus hallei rubberlip seaperch Rltococltilus toxotes salema Xenistitts califumiensis ! sarcasticfringehead N eoclitttts blanchardi sargo Ani sotrenus davids otti senorita Oryjulis califomica shinerperch Cynwtogqster agregata I shovelnoseguitarfish Rhinobatos prodttctus sloughanchovy Artclna delicatissima speckledsanddab Ci th ai chthys stign a eus I specklefinmidshipman Poichthys myiaster spinybodish Ostracion diaphanum spinydogfish Squahrcacantlias spotfincroaker Roncador steantsi ' T spottedcusk-eel Chilara tayloi spottedkelpfish Gibbonsia elegans spottedsand bass Pa ra I a brax nnail atofas ci atus t spottedturbot P I euronichtltys itt eri stripedkelpfish Gibbonsia metzi thornback P Ia tyrhinoi di s trisei ata I topsmelt Atheinops ffinis treefish Sebastesseniceps walleyesurfperch Hyperyrosopon utgenteum white croaker Genyonenruslineatus I white seabass Atractoscion nobilis whiteseaperch Plnnerodonfitrcatus yellowsnake eel Op h i c lttltus zopltoc hi r t yellowfincroaker Untbina roncador yellowfingoby A ca nth ogob itrs flavinrcnu s yellowtail Seiola lalandei zebraperch Hemtosilla an.rea I I 54 I I I Table 6 pageI of2

t Number, biomass and mean weight per fish for fish IMPINGED on travelling screensin SONGS Units 2 & 3. Totals are the sum of 191 samplestaken during full- flow operations lbr the period May 1983 - August 1986. Sample dates are shown in I Table 1. Only specieswhich had > 20 fish entrapped are shown. Total fish includes all speciesin samples. Speciesare ranked by the combined weight of impinged and I diverted (Table 7). SPEcIES NUMBER BIoMASS MEANWT. I (xc) PERFrsH (c)

queenfish L27,',130 1.,384.685 11 I northern anchovy 86,08L 31.r.275 4 jacksmelt 3,095 374.094 Lzl yellowfincroaker 11 0.834 76 bat ray 26 1"00.810 3,877 I Pacificelectric ray 30 237.748 7,925 zebraperch 0 0 0 white croaker 34,995 1.56.9L3 4 t shovelnoseguitarfish 7 3.601 5L4 salema 91. 1.300 L4 Californiacorbina 83 10.555 L27 kelp bass 1.1 0.573 52 t sargo 41. 0.938 23 round stingray 47 18.,|f}9 393 Californiahalibut 65 L3,46 204 I white seabass 58 2.573 44 topsmelt 31 0.894 29 graysmoothhound 8 3.061 383 Pacificpompano 2,701, 28.727 11 I chubmackerel 88 L2.49 L4L thornback 122 4r.082 337 barredsand bass 51 14.443 ?43 I spotfincroaker 6 1.100 183 sloughanchovy 12,412 35.L25 J deepbodyanchovy 2,1,58 2r.762 1.0 walleyesurfperch 226 3.562 L6 I specklefinmidshipman L?3 28.634 224 white seaperch 683 5.?64 8 spinydogfish 29 15.504 535 I plainfin midshipman 576 21.755 38 opaleye 2 0.656 3?A pile perch 2 0.004 z I Californiascorpionfish 119 10.049 u black croaker 1 0.005 5 black perch 19 0.280 15 Pacificbarracuda 101 3.568 35 I jack mackerel 345 3.008 9 giant kelpfish 219 6.396 29 l T 55 t

Table 6 I page2 of2 I SPECIES NUMBER BIoMASS MEAN WT. (Kc) PERFrsH (c) I spotted turbot 64 5.747 80 blacksmith 2 0.100 50 halfmoon 0 0 0 I California California grunion 82 2.357 29 shiner perch 339 2.39r diamond turbot 12 3.460 288 I garibaldi 0 0 0 Pacific sardine 38 1.484 39 pipefish r39 3.815 27 spotted cusk-eel 35 2.r22 6L t rock wrasse 15 0.811 54 cabezon 5 0.545 109 fantail sole 19 0.563 30 I rockfish spp. 2 1.408 704 rubberlip seaperch 0 0 0 Pacific stagborn sculpin 1.9 0.726 38 kelp perch 10 0.t62 L6 I speckled sanddab 35 0.519 15 basketweavecusk-eel ?a 0.4r7 15 bocaccio L2 0.079 I blenny spp. 45 0.147 3 spotted kelpfish 6 0.074 L2 striped kelpfish I 0.003 J I California sheephead 0 0 0 all other speciescombined 97 13.376 I Total Fishes 273,403 2,9t4.662 I I I I I T 56 I I I Table 7 pageI of2

T Number, biomass and mean weight per tish lbr lish DMRTED to the Fish Return Systemat SONGS Units 2 & 3. Totals are the sum of 191 samplestaken during full- flow operations for the period May 1983- August 1986. Sample dates are shown in t Table 1. Only specieswhich had > 20 tish entrapped are shown. Total lish includes all speciesin samples. Speciesare ranked in the same order as Table 6. I SPECIES NUMBER BIoMAss MEANWT. (c) I (xc) PenHsH queenfish 329,792 5,245.597 L6 northern anchovy 872,874 t,r9t.997 r.4 jacksmelt 4,440 649958 146 I yellowfincroaker 2,602 639.949 246 bat ray 52 398.250 7,659 Pacificelectric ray 2l 244.850 11,660 I zebraperch 720 402.055 558 white croaker 33,996 233.376 7 '76 shovelnoseguitarfish 269.4q 3,545 salema 5,063 200.660 4 I Californiacorbina 495 123.574 250 kelp bass 505 t24.977 247 sargo 586 L24.389 2L2 I round stingray r97 82.845 42I Californiahalibut 204 82.8r2 406 white seabass 359 88.703 247 I topsmelt 951 82.316 87 graysmoothhound 6t 72.0r5 1,18l, Pacificpompano 2,1r0 210.598 19 Chub mackerel 308 54.4q 177 l thornback 46 23.960 52L barred sandbass 198 45.564 2n spotfincroaker 770 ,t8.578 2K I sloughanchovy 4,663 11.565 2 deepbodyanchovy 2,8r2 24.605 9 walleyesurfperch 3,504 41.891 L2 specklefinmidshipman 24 7.304 304 I white seaperch 1,115 25.005 22 spinydogfish 15 7.6W 507 plainfin midshipman 25 r.n2 51 I opaleye 29 19.5,10 674 pile perch 43 18.4L3 4?A Californiascorpionfish 31 4.300 r39 't7 black croaker rz.0'16 r57 l black perch 94 11.069 118 Pacificbarracuda 53 7.566 r43 jack mackerel 175 6.9?5 40 I giant kelpfish 60 3.043 51. t I 57 I I Table 7 page2 of? I SPEcrEs NUMBER BIoMASS MEANWT. (Kc) PERFTSH (c) I spottedturbot 45 2.778 62 blacksmith 81 6.697 83 halfmoon 27 6.624 245 I Californiagrunion 105 3.005 29 shinerperch 272 2.7L2 L0 diamondturbot 8 L.377 172 I garibaldi 1.1. 4.800 436 Pacificsardine TI2 2.855 )< pipefish 0 0 0 spottedcusk-eel 17 0.793 47 I rock wrasse 13 1.,100 108 cabezon J 1.559 520 't4 fantail sole 0.920 6 t rockfishspp. t) 0 0 rubberlip seaperch 14 1,.r14 80 Pacificstaghorn sculpin 1 0.100 100 t kelp perch 1"1 0.566 51 speckledsanddab 8 0.03r. 4 basketweavecusk-eel 4 0.068 L7 bocaccio 11 0.064 6 I blennyspp. 0 0 0 spottedkelpfish 1 0.0L2 t2 stripedkelpfish 0 0 0 I Californiasheephead 0 0 0 all other speciescombined 74 78.347 I Total Fishes 1,,?69,379 10,788.900 T I I I T T 58 t I

Table I I page1 of2

Average body weight and size classitication for fishes entrapped at SONGS Units 2 I & 3. Estimates and classification are based on the averageweight of frsh in all impingement and diversion samples (n = 191) at both new unit during the period May 1983 - August 1986. Fishes are classified either as small (S, < 30 g), medium t (M,30 - 199 g), or large (L, > 200 g).

AVERAGEBODY BODY SIZE I SPECIES wErcnr(c) crAssrFrcATroN

Pacificsanddab 1 S l doversole 2 S northern anchovy 2 S Pacificherring 2 S I round herring 2 S blennyspp. J S sloughanchovy J S I stripedkelpfish J S rockpoolblenny 4 S bocaccio 6 S treefish 6 S I white croaker 6 S shinerperch 8 S deepbodyanchovy 9 S I spottedkelpfish I2 S walleyesurfperch 12 S speckledsanddab 13 S Pacificpompano t4 S I queenfish T4 S basketweavecusk-eel 15 S white seaperch I7 S I jack mackerel L9 s yellowfin goby 22 S California tonguefish 23 S pipefish 27 S I Californiagrunion 29 S Pacificsardine 29 S I giant kelpfish 34 M kelp perch 35 M senorita 36 M plainfin midshipman 38 M I salema 39 M Pacificstaghorn sculpin 4l M spinybodish 43 M l fantail sole 45 M spottedcusk-eel 56 M Pacificbarracuda 72 M I spottedturbot t3 M rock wrasse 79 M t I I

Table 8 page2 of2 I

AVERACEBODY BODY SIZE I SPECIES WErcrrr(c) Cu,ssrFrcAlroN rubberlip seaperch 80 M I blacksmith 82 M hornyheadturbot 82 M topsmelt 85 M I Californiascorpionfish 96 M black perch 100 M jacksmelt 136 M black croaker 1.54 M I barredsurfperch 156 M Chubmackerel 169 M spottedsand bass 170 M I Californializardfish 188 M rainbowseaperch 200 L I sargo 200 L white seabass 2r9 L Californiacorbina 232 L specklefinmidshipman 236 L I barred sandbass 24r L diamondturbot 242 L kelp bass 243 L I halfmoon 245 L yellowfincroaker 245 L cabezon 263 L spotfincroaker 282 L I Californiahalibut 357 L thornback 38',7 L pile perch 409 L I round stingray 4L5 L garibaldi 4'36 L spinydogfish 525 L zebraperch 558 L I yellowsnake eel 620 L opaleye 651 L Pacificbonito 700 L I brown rockfrsh 704 L brown smoothhound 730 L graysmoothhound 1088 L horn shark 11,49 L I Californiabutterfly ray 1814 L finescaletriggerfish 2L50 L leopardshark 2777 L I shovelnoseguitarfish 3289 L bat ray 6398 L Pacificangel shark 8500 L I Pacificelectric ray 9M3 L t 60 I I I Table 9 pageI of2

I Number, biomass and mean weight per fish for fish impinged during HEAT TREATMENTS at SONGS Units 2 & 3 for the period May 1983 - August 1986. Dates of heat treatments are given in Table 2. only specieswhich had > 20 tish I entrapped during the period are shown. Totat tish includes all speciesin samples. Speciesare ranked in the same order as Table 6. I SPEcIES NuNaesn BIoMASS MEAN WT. I (KG) PERFTSH(c)

queenfish 79,112 698.066 9 northern anchovy I 98,325 300.678 J jacksmelt 462 6r.537 133 yellowfincroaker 8,785 3,084.650 351 bat ray J 10.140 3,380 I Pacificelectric ray 2 17.300 8,650 zebraperch 3,361 1,881.662 560 white croaker 506 10.136 20 I shovelnoseguitarfish 45 137.030 3,045 salema 3,6t5 1.59.207 44 Californiacorbina 36 8.294 ?30 kelp bass 925 187.658 203 I sargo 8,1,47 2,t39.265 263 round stingray 61 29.808 89 Californiahalibut 65 77.360 257 I white seabass 36 7.352 204 topsmelt 115 6.045 53 graysmoothhound 4.045 578 Pacificpompano 240 4.809 20 l Chub mackerel 32 4.433 r39 thornback 7 2.080 297 barred sandbass 1,395 354.448 254 I spotfin croaker 626 375.385 600 sloughanchovy 212 1.014 5 deepbodyanchovy t,746 24.701 L4 walleyesurfperch L40 5.762 4T T specklefinmidshipman 8 2.409 301 white seaperch 45 r.543 34 spinydogfish 0 0 0 I plainfin midshipman 72 3.968 55 opaleye 89 49.640 558 pile perch 29 9.020 3tL Californiascorpionfish 89 L3.244 r49 l black croaker r97 33.658 t7r black perch 76 12.339 L62 Pacificbarracuda 64 3.789 59 I jack mackerel 284 23.184 82 giant kelpfish 63 2.0r0 32 I I 6I T I Table 9 page2 of2 t SPECIES NUMBER BIoMAss MEAN WT. (Kc) PERFTSH(c) I spottedturbot ?a 0.582 2I blacksmith 135 L0.907 81" halfmoon 25 6.614 ?55 I California grunion 26 0.?58 10 shinslpslsh 98 1.041 LL diamondturbot 2 0.222 111 I garibaldi 32 14.655 458 Pacificsardine 4 0.025 6 pipelish T2 0.025 2 spottedcusk-eel J 0.L24 4L I rock wrasse 87 13.190 L52 cabezon 39 6.083 156 fantail sole 0 0 0 I rockfishspp. 23 4.596 ?n0 rubberlip seaperch 1.0 2.933 293 Pacificstaghorn sculpin 1 0.003 5 kelp perch L2 0.317 ?5 I speckledsanddab 2 0.020 10 basketweavecusk-eel E 0.038 5 bocaccio 4 0.07r 18 t blennyspp. 5,%g LL.753 2 spottedkelpfish 55 0.L23 2 stripedkelpfish t20 0.r92 ) I Californiasheephead 26 18.630 717 all other speciescombined q 22.3y I Total Fishes 2r5,r83 9.801.81.5 Total No. Taxa = 63 I I I I I T 62 I t I Table 10 pageI of2

I Number, biomass and mean weight per lish for fish impinged during HEAT TREATMENTS at SONGS Unit 1 for the period May 1983 - August 1986. Dates of heat treatments are shotn in Table 2. (Note that no heat treatments occurred at I Unit 1 during May 1983 - Dec 1984.) Speciesare ranked by total weight. I SPECIES NUMBER BIoMASS MEAN WT. l (KG) PERFISH(G) sargo 2885 423.840 1.47 yellowfincroaker t24r 170.044 r37 I spotfin croaker 22L 109.522 496 zebraperch 52r 92.080 177 jacksmelt €5 54.050 111. I queenfish r776 47.670 )1 walleyesurfperch rr93 46.470 39 black perch 271 39.630 LM I black croaker 330 38.879 11.8 kelp bass 146 37.840 259 opaleye 79 34.6n 438 salema 858 33.527 39 I barred sandbass 191 33.290 174 halfmoon 106 25.226 238 shovelnoseguitarfish 4 15.700 3925 I Californiacorbina 69 14.380 208 pile perch 50 13.265 ?55 ' garibaldi 3L 11.820 381 white seabass 75 71.037 L47 l threshershark 1 9.500 9500 Pacificangel shark 1 9.500 9500 Californiasheephead 11 9.070 825 I blacksmith 95 6.013 63 round stingray 10 5.330 s33 Californiascorpionfi sh 19 2.955 r.56 topsmelt 63 2.905 46 t white seaperch 36 2.553 71. horn shark I 2.030 2030 brown rockfish 11 1.738 158 I giant kelpfish 23 1.690 73 Pacificbarracuda 1.53r. 219 grassrockfish 4 1.310 3n rock wrasse t6 1.222 76 l cabezon 8 0.930 LL6 thornback 2 0.640 320 Chub mackerel 4 0.630 158 I specklefinmidshipman 2 0.450 225 barred surfperch 1 0.390 390 I I 63 I I Table 10 page2 of2 I SPECIES NUMBER BIOMASS MEANWT. (KG) ren Frsu(c) I deepbodyanchovy 33 0.366 1.1. spottedsand bass 4 0.350 88 Pacificpompano 5 0.224 45 I 1 rubberlip seaperch I 0.190 L90 Pacifichalibut 1 0.140 T4 a white croaker J 0.r02 34 I shinerperch 4 0.091 23 spottedturbot 4 0.084 2l jack mackerel 2 0.076 38 blennyspp. 11 0.053 5 I plainfin midshipman l" 0.041 4l northernanchovy 2 0.034 L7 Californiagrunion 1 0.016 L6 I fantail sole I 0.009 9 spottedkelpfish 2 0.006. J T Total Fishes L0,922 1,315.066 Total No. Taxa = 54 I T T I T I I I I 64 T t I Table 11

Annual (12-month) estimates of entrapment for SONGS Unit I and Units 2 & 3, Estimates are I based on heat treatment, impingement and diversion samples during the 39 month period from May 1983 'August 1986. Shorvnare estimatestbr both numbers and biomass (kg) for 17 selected species,all other speciescombined and the total of all speciescombined. a indicates that Unit 1 I estimates for queenfish,northern anchovy and white croaker were calculated from Units 2 & 3 estimates rather than from Unit I samples becauselarge numbers of these species were extruded through the large-mesh screen in Unit I and therefore were missing from Unit L samples. See (l methods for a detailed description of techniquesused to calculate the annual estimates.

I ANNIJAT.F-snnrnrp^s NUMBERS ------BroMAss (KG) I UNITl UNnS2&3 UNrrl Ulnrs2&3 queenfish 53,864a l_,125,509 681"4 L4,2:25 t northern anchovy 199,ggga 4,179,959 2W 4,799 jacksmelt 450 29,021, 55 3,9n '1,4,51,4 yellowfin croaker 425 55 3,925 I Pacific electric ray 116 136 L,23L L,3'X white croaker 5,9394 124,072 424 885 salema L,018 14,355 27 5L9 I kelp bass 67 r,577 15 377 'J.44 California corbina 1,569 2A 342 I barred sand bass 82 L,274 19 307 spotfin croaker 93 788 52 246 Pacific pompano 204 12,970 4.5 2r4 t walleye surfperch 2,219 12,471, 58 163 white seaperch 37r 5,324 4.4 75 black croaker 193 345 L7 69 topsmelt I 79 57t J.J t6 California grunion L7 498 0.2 10 I all other speciescombined 7,A52 75,760 1,663 5,432 t Total fish n2320 5,599,611 4,186 36,868 t I t I 65 I I Table 12

Annual estimates of the NUMBER of tish either killed during HEAT TREATMENTS, IMPINGED on travelling screens or DIVERTED to the Fish I Return System in SONGS Units 2 & 3. The annuat estimate of the total number of lish entrapped in Units 2 & 3 is shown in Table 11. Percent diverted = (number of lish diverted / totat number entrapped) x 100. Shown are estimates for 17 select I species,all other speciescombined and total tish. Estimates for small, medium and large size classes are also shown. Average size classification for each species is indicatedbyL = large,M = medium,S = smatl. I

PERCENT SPECIES HEATTREATMEN"T IMPINGED DTVERTED DTVERTED I queenfishs 24,342 307,225 793,941 70.5 northern anchov5F 30,254 373,374 3,775,230 90.3 I jacksmeltM 1.42 11,869 17,0L0 58.6 yellowfin croakerl 2,703 32 LL,779 8L.2 I Pacific electric raf 0.6 79.4 56 4L.2 white croakef 156 62,825 61,091 49.2 'l,,rr2 I salemaM 238 L3,005 90.6 kelp bassl 285 n L,?65 80.2 t California corbinaL 11 224 1,334 85.0 barred sand bassl 429 173 672 52.7 spotfin croake* r93 20 575 73.0 I Pacific pompanos 74 7,235 5,6L 43.6 walleye surfperchs 43 758 LL,670 93.6 I white seaperchs t4 2,018 3,292 61.8 black croakerl' 61 4 ?40 8r.2 t topsmeltM 35 17 519 90.9

California grunions d 2r5 275 55.2 al! other speciescombined 6,347 27,4r8 4L,gg5 55.4 I I Total Fish 66,2r0 793,751 4,739,650 84.6 smallspecies 57,335 778,107 4,691,,060 84.9 I mediumspecies 1,559 14,1,57 33,670 68.2 I '1,316 largespecies 1,48'7 24,920 73.9 I 66 I I

I Table 13 Annual estimates of the BIOMASS (kg) of fish either killed during HEAT TREATMENTS, IMPINGED on travelling screens or DIVERTED to the Fish I Return System in SONGS Units 2 & 3. The annual estimate of the total biomass of fish entrapped in Units 2 & 3 is shorm in Table 11. Percent diverted = (biomass of fish diverted / total biomass entrapped) x 100. Shown are estimates for 17 select species,all other speciescombined and total fish. Estimates for small, medium and t large size classes are also shovm. Average size classilication for each species is I indicatedbyL = large,M = medium,S = small. PERcENTT I SPECIES HEATTREATMENT IMPINGED DIVERTED DIvERTED queenfishs 2r5 2,9?3 11,083 77.9 I northern anchov5F 93 974 3,732 77.8 jacksmeltM 19 1,426 2,482 63.2 yellowfin croakerl 949 L 2,975 75.8 I Pacific electric rayl 5 656 675 50.5

white croakeF J 355 5n 59.5 I salemaM 49 .' 467 90.0 kelp bassl 58 2 317 84.1 I California corbinal .) 27 3r2 9L.2 barred sand bassl 109 la 150 €.9

spotfin croakerl 116 J In 51.6 I Pacific pompanos 1.5 88 124.5 58.2 walleye surfperchs 2 13 1-zE 90.8 l white seaperchs 0.5 L3 61.5 82.0 black croakerM 10 0 59 85.5 I topsmeltM 2 0.2 13.8 86.3 California grunions 0.1 4.4 5.s 55.0 I all other speciescombined 1,38L 697 3,354 6L.7

t Total Fish I smallspecies 334 4,46'7 15,815 76.7 mediumspecies t02 1,555 3,190 65.8 I largespecies 2,580 7,217 7,608 6.7 t I I I Table 14 T Results of 1983-1985field experiments to estimate percent mortality of fishes entrapped in SONGS Units 2 & 3 and subsequently discharged from the Fish Return System (fRS). Shown is the total percent mortality during the first 4 days after discharge which includes fish that were dead when discharged. nother speciesnis the sum of all species t with less than 10 fish in experimental pens. :- indicates there were no fish in the control nets. Nc indicates that there was no control for this species since there were no fish in the control nets. 5 indicates that the control data were insullicient and therefore the results of the control were disregarded. b indicates only shiner surfperch were c d I found in control pens. indicates only black croaker were lbund in control pens. indicates only 4 species were found in control pens. Numbers in ( ) are half-width of 95VoCl, Size categories are given in Table 8. Estimate of 7o mortality of small fish is the weighted mean of mortality estimates for the 4 small species with adequate controls. Estimates for medium and large lish are weightedmeans of mortality estimatesfor all speciesin the 2 size classes. I

EXPERIMENTAL PENS CONTROL PENS ---...-- 96Monrat-rrv t DUETOFRS Vo NO. OF No. oF Vo No. oF No. oF EXPERIMENTAL -- MoRTALTTY PENS FISH MORTALTY PENS FISH CONTROL I

SMALLSPECIES deepbody anchovy L3 4 175 NC t northern anchovy .' 10 5564 1 Nc9 slough anchovy 100 J 100 :: Y NC Pacific pompano 7 2 14 -: NC <) white croaker 10 155 0 J t2 s2 (8) I walleye surfperch 3 9 Q 0 5 20 3 (s) white seaperch 7 7 30 0 J 8 7 (e) queenfish s) 18 2753 20 9 185 32 (6) t 2 other species 0 5 6 0 2 5u NC

MEDIUMSPECIES salema 0 12 NC t topsmelt 30 2 NC 6 other species 0 9 ; 0 T [-A.RGESPECIES yellowfin croaker <1 0 9 other species 5 NC I

VoMortality for size classes Smallspecies= 32Vo I Medium species=?3Vo Large species= IVo I I I I I I I

I Table 15 Percent mortality of small (5i 100 mm SL) and large ( > 100 mm SL) queenfish entrapped in SONGS Units 2 I and 3 and subsequentlydischarged in the Fish Return System (FRS). Shown is the total percent mortality during the first 4 days after discharge which includes tish that were dead when discharged. Numbers in ( ) are half-width of 9SVoCI. One experimental and one control pen were not included in the analysis because t {ish were not measured. No. of fish is the total of the initial numbers of fish in pens.

I EXPERIMENIAL PENS CoTvTnoI PBNs DIFFERENCE SIZE EXPERIMENTAL-- Cless Vo No. oF No. oF % No. oF No. oF coNTRoL MORTALITY PENS Flsrr MoRTALTY PENS FISH % Monral-rrv I DUETOFRS I I I I I I I I I l I 69 I T Table 16

Percent elliciency for number and biomass of fish for the Units 2 & 3 Fish Return System t (FRS). Percent diversion estimates are from Tables 12 and 13. Diversion estimates for small, medium and large fish are weighted averages of percent diversion for small, medium and large species. Percent survivorship of transport through FRS was estimated I from survivorship experiments reported in Table 14. Percent efliciency of FRS including FRS transport survivorship is the product o[ percent diversion and percent FRS transport survivorship. I I 7oEprrcrcNcy INcLUDINGsuRvrvoRsHrp oF FRS TRANSPORT ONLY SPEcrEs/ I GRoUP 7oDtvenstoN | 7, Sunuv- | EoEFFrcrENcy tl -I ORSHIP I- IFRSI T NuMenn BroMAss lTRaNspoRrI NuMsen BroMAss northern anchovy 90 78 97 87 76 I Pacific pompano 44 58 93 41. 54 white croaker 49 60 zA 24 29 I walleye surfperch 94 9r 97 91, 88 white seaperch 62 82 93 58 76 queenlish 71. 78 68 48 53 I salema 91" 90 100 91 90 topsmelt 97 86 70 64 60 yellowfin croaker 81 76 100 81 76 I

Small-bodiedspecies 68 76 68 46 52 t (minus anchovy) Medium-bodiedspecies 68 66 77 52 51 I Large-bodiedspecies 74 67 100 74 67 I I I I I 7.0 FIGURES Figure1: Map of the Los Angeles- San Diegoregion showing the locationof the San Onofre NuclearGenerating Station (SONGS).Schematic shows location of intakepipes and dischargeconduit for the FishReturn System. s)-oootrcCrcch

0 r 2 3 { s 6 ffi lilometers

Dift uraJI 15m l2m

Disloncefrom Shorein Kilometers Figure2: Diagramof the SONGSFish Return System. t

al T > r=3= =E= E=E I E-E< r_ E.ta J l t -l -l Lr.l I = -, l*l ltl I c= CJ ct) t ara ou -, E ttt 4) - B ei) cl E E - E C' B - E .E v) c) - I 3r7 E - tu) a C' E tu) CJ lct B = - E .t - EI C9 GI E E - F - EI Ilg - rt e EI - -t tE aA > a3 I := EI - E -E != l*l rcg > e .E J G9 ;- c9 CE -, - bl -, -. l- l- rr .E E lr, .C e F- > I - .E J G,' e e - CJ f- - - c, - Iu t vit

tult E' H F U 4 rcll t- L. c5 rrrl I I al l- et .C -, =ll - G =-Jl I 19 -lYl

C( = =tll I == t-l Vl cJ rdl I CJ e GEI I !l e c) :tt I C' lr| E 2! I tll tl I E L-l/ I V r.l EI tc, CJ I e e aa bl EI < :IE - aA C' ltt EC e, UI -. -. lEl I GT Figure 3: Diagramof the etevationand sluicing channelfor SONGS FishReturn System.

76 I FISH trlETv|OVAL ELEVATOtr A]\Itrl t SLTJICII\IG CHAAIT\IEL t ,- FISHTLEUATOR DRAW j TRAIIELINGWATER W(IRI(S])RII,E fYIECHANISM SCREEI{ SUPPI)RTFRAMES At{D I GUII)ES FISHFLUSHII{G I MANIF()TD ELEIJATI(}N --- [0cALcol{TRoL t 16'-0'r c0ils0LE I FISHELEI'AT(}R BUCI(ET I SLUICIIIGtfATER flsHslurctr{G II{LETLINE I DISCHARGE ()PENSLUICING t CHANNET t FISHH()LDING FL()WDltllDlilG I CHAMBER(ONSHTO BARRIER(PART t}F Ut{EPR0FILE ) -- I INTAI(ESTRUCTURT) l \i ':i::; I .'1.' I T FISHBUCKET AT T()WESTP(}SITI()N I FISHIIILET FL(}IT I Et.(-)26'- 0" APPR0X-l 25'DttP t 77 t I I I t t I I Figure4: Histogram of the size distributions of queenfish in impingementand diversion samples in SONGSUnits 2 & 3. Datawere pooled over all 191 quantitativesamples. Fishwere dividedinto 20 mm lengthclasses. n = total numberof fish measuredin samples.

78 QUEENFISH 60.0 Units2 & 3

50.0

40.0

30.0

20.0

10.0

0.0 zt- Ld () E Ld [L 60.0

50.0

40.0

30.0

20,0

10.0

0.0 80 100 120 140

LENGTH

79 Figure5: Histogramol the size distributionsof northernanchovy in impingementand diversionsamples in SONGSUnits 2 & 3. Data were pooled over all 191 quantitative samples. Fishwere dividedinto 10 mm lengthclasses. n = total numberof fish measuredin samples. t I

T NORTHERNANCHO\^/ I 25.0 Units2 & 3 20,0 IMPINGED t n = 2769 t 15.0 T 10.0 I 5.0 0.0 t 0 10 20 30 40 50 60 70 80 90 100110120130140 z lrJ CJ I E, hJ IL l 25.0

T 20.0

I 15.0

t 10.0

T 5.0

I 0.0 t 0 10 20 30 40 50 60 70 80 90 10011012A130140 il LENGTH 81 l, Figure6: Histogramof the size distributionof white croaker in impingement,diversion and heat treatmentsamples in SONGSUnits 2 & 3. Data were pooledover all samples. Fishwere dividedinto 20 mm lengthclasses. n = total numberol fish measuredin samples.

I I I t T

82 ,I I WHITECROAKER I Unite2 & 3 I 60.0 50.0

I 40.0 I 30.0 20.o

I 10.0

0.0 I 100 12O l,t0 160 lEO 2OO

I 60.0 50.0 t 4o.0 2 lrl o 50.0 I E trJ o- 20.o

I 10.0

0.0 t 100 120 140 160 1E0 200 I 60.0 50.0

I 40.0 I 30.0 20.o

I 10.0

0.0 I E0 r00 120 140 180 160 200 I LENGTH I 83 Figure7: Histogram of size distributions of queenfish in impingementand heat treatmentsamples in SONGS Unit 1. Datawere pooled over all samples. Fish were dividedinto 20 mm lengthclasses. n = total numberof fish measuredin samples.

84 QUEENFISH Unit 1 40.0

30.0

20.0

10.0

0.0 zF ld c) E. IJ TL

40.0

30.0

20,0

10.0

0.0 80 100 120

LENGTH

85 Figure8: Histogramof size distributionsof white croaker that lived and died in pens in the survivorship field experiment. Data were pooled over all experimental trials. Fishwere divided into 20 mm length classes.n = total numberof fish measured.

86 WHITE CROAKER

80.0 Lived 70.0 n=70 60.0 s0.0 40.0 30.0 20.0 10.0 0.0 30 110 130 150 17A 190 zF lrJ o E, lrJ (L E0.0 Died 70.a n=55 60.0 50.0 40.0 30.0 20.o 10.0 0.0 30 110 130 150 170 190

LENGTH

87 This pageintentionally left blank. I

I APPENDIXA I Comparisonof entrapmentat I Units 2 and3 Sincethe designand operational features of SONGS Units 2 and 3 are the I same, the composition and number of fish they entrap should be similar. I Entrapment at Units 2 and 3 was compared using data from quantitative impingement and diversion samplescollected over 24 hours during full flow (4 I pumps)operations on the sameday at the two units. Samplescollected on 35 dates I from March 1984to SeptemberL985 (Table A-1) were includedin the analysis. The rank order of the top 20 speciescaught in each unit, by abundance,is I shownin Table A-2, and by biomassin Table A-3. The results of a Kendall's Tau I test show that the rankingsfor Units 2 and 3 were correlated for both number and biomass(Table A-4). Therefore,the speciescomposition at the two units is similar. I Actual entrapment rates, both number and biomass,of the two most abundant species, queenfish and northern anchovy, and of total fishes were also not I significantlydifferent at the two units (Table A-5). I Comparisonof Entrapmentat DifferentFlowVolumes I The method usedto estimatemonthly entrapmentof fish at all SONGSunits I assumesthat the number and biomassof fish entrapped is positively and linearly related to the volume of water pumped through a unit. This assumptionwas tested I by comparing entrapment at one new unit when it was operating at full flow (4 t pumps) and the other new unit when it was concurrentlyoperating at less than full

I A-1 I I I flow (fewer than 4 pumps). There were 17 datesthat satisfiedthis criterion (Table ,{-6). First, entrapment in the unit operating at less than full flow was adjustedto I the full flow level using the factorslisted in Table .4-6. Then a two-tailed paired t- I test was used to test the hypothesis that there was no difference between entrapmentat full flow and the adjustedentrapment. The analysiswas done for the I 4 of the most abundant species,queenfish, white croaker, walleye surfperch,and northern anchovy,as well as all fish combinedand all fish minus northern ancholy. I The resultsshow that there is no significantdifference between the entrapment,for either numbers or biomass,when it was measuredunder full-flow conditions and I concurrently under less than full-flow conditions and then adjusted (Table A-7). I Therefore, the assumption that the magnitude of entrapment is positively and linearly related to the volume of water pumpedcan be accepted. I

Comparisonof Entrapmentat Unit t with Units 2 and3 I

Comparisonsof entrapment at Unit 1 with Units 2 and 3 were based on I quantitative 24 hr full-flow (2 pumps for Unit L and 4 pumps for Units 2 and 3) I entrapmentsamples collected on the sameday at Unit 1 and at one or both of the new units. Since previous analysesshowed that the magnitude of entrapment at I Units 2 and 3 was not significantlydifferent, if sampleswere collectedat both Units 2 and 3 on the sameday as Unit L, the data from the new units were averagedand I the meanw:N comparedwith data from Unit 1. I The 5/8 inch meshof the travelling screensin Unit 1 is two-thirds larger than I the 3/8 inch mesh of screensin Units 2 and 3. As a result, somesmall fish that are impingedon screensin Units 2 and3 passthrough the screensin Unit 1 and are lost I

A-2 t I t I from samples. This introducesa bias in any comparisonof entrapment at Unit 1 I with Units 2 and 3. This bias can be eliminatedby including in the analysisonly size I classesof fish that are fully retained on the large mesh screensin Unit 1. The smallestsize fish that would be unable to passthrough screensin Unit 1 and Units 2 I and 3 was determined using Margraff et al.'s (1985) application of the "fineness ratio" formula of Turnpenny(1981, Equation L4). For each speciesof fish, the I finenessratio is a function of body shapeand is calculatedas the mean of (body length / body depth). Finenessratios were calculatedfor queenfish,white croaker, I and northern anchovy,the most abundant speciesin impingement and diversion I samplesin Units 2 and 3. The ratio was basedon measurementsfrom at least 65 individuals covering a wide range of lengthsfor each species. Ratios were 3.9 for I queenfish,3.8 for white croaker and 6.6 for northern anchovy. The much higher I ratio for northern anchow reflectsits relativelv slenderbodv. The finenessratio was used to determine the standardlength of the smallest I fish that would be retained by a screenof a specific.mesh size. This was estimated I as the minimum length of fish whose deepestbody section cannotpass through the screenand is, therefore, very conservative. Minimum lengthsfor queenfish,white I croakerand northernanchovy retained on screensat Unit L were 1.1.3mm, LL0mm, and 190 mm, respectively,and at Units 2 and 3 were 57 mm, 55 mm, and 95 mm, I respectively. I To avoid the bias causedby differencesin screenmesh size at Units 1 and I the new units, the comparisonof entrapmentat the units is basedon the number of only large queenfish( > 100 mm SL) in same-daysamples; the very conservative I estimate calculatedfrom the "finenessratio" for queenfish indicates that this size

I A-3 I I I classshould be fully retainedon screensin all units. White croaker and northern anchorywere not used becausethere were too few indMduals in the large size I classesin entrapmentsamples at Unit 1. I Frequently,the lengthsof all queenfishin a samplewere not measured. To I estimatethe number of large queenfish,the total number of queenfishin a sample was multiplied by the proportion of measuredindMduals that were > 100 mm. I Sampleswere includedin the analysisonly if the following criteria were met: (L) there were at least 35 queenfishin the sample;(2) lengthsof at least 75 individuals I were measuredin sampleswith more than 100 fish; (3) in sampleswith 100 fish or I less,the lengthsof at least 75Voof the fish were measured. There were L5 dates when samplescollected at Unit 1 and one or both of the new units satisfied the I criteria (TableA-1). t When all pumps are operating, each of the new units pumps about 2 1,/2 times the amount of water pumpedby Unit 1. Basedon this observatioq DeMartini I and Larson(1980) predicted that eachnew SONGSunit would entrap2.5 timesthe I amount of fish entrappedin Unit 1. This prediction was tested by comparingthe number of queenfishentrapped in either new unit (or the averageof the two units if I both were sampled)with 2.5 times the number of fish entrappedin Unit 1. t There was a significant differencebetween the number of fish entrappedin I Unit 1 and the new units (Table A-8). Therefore, the hypothesisthat eachnew unit entraps 2.5 times the number of fish entrapped in Unit 1 must be rejected. The I mean of the differencesof the log transformeddata for the samplepairs was usedto determinethat the number of queenfishentrapped in a new unit was about 7.7 times I

A-4 I I I I the entrapmentat Unit 1, so Units 2 and 3 combinedentrapped about 15.4times I more queenfishthan Unit 1 (Table A-8). I The comparisonbetween units was done for the number of fish entrapped t only. Methods used to estimate the number of queenfish in the large size class cannot be used to estimate the weight of queenfish in the size class because I individual fish in a sample were not weighed; only aggregatewet weights were measuredfor each species. The size distribution of large fish was used to estimate I the ratio of biomassof entrappedfish at the different units. The size distributionsof I large queenfish in samplesfrom Unit L and Units 2 and 3 were determined by pooling the lengths of all fish measuredon the 15 sampledates over each type of I unit and dividingthe pooleddata into L0mm sizeclasses. Although there may be a slightly higher proportion of individualsin the largestsize classesin Unit 1 samples, I the distributions are similar (Figure A-1). Therefore, the ratio of the number of queenfishentrapped in the new units and Unit 1 is also a good approximationfor I biomass. I It wasn't possibleto compare entrapment at Unit 1 with Units 2 and 3 for I speciesother than queenfishbecause the minimum size retained on screenscould not be determined. (Although the minimum size of fish retained on screenswas I determined for white croaker and northern anchovy,sample sizes of the length I classesthat do not pass through the screensat Unit 1 were too small to use for comparisons.)Because the minimum lengthsretained on screensfor queenfishand I white croaker are very similar (113 mm and 110mm, respectively,for Unit 1), the ratio of entrapmentat a new unit to entrapmentat Unit 1 for queenfishis probably I a good approximationfor white croakeralso. The minimum lengthof fish retained

I A-5 I on screensin Unit 1 is much larger for northernanchovy than queenfish(190 mm and 110 mm, respectively). Therefore, although the ratio of entrapment for queenfishis the best estimate available for northern anchovy,it is most likely an underestimateof the actual ratio betweenthe magnitudeof entrapment at the new units and Unit 1.

A-6 I I Table A-1 pageI of2

I List of dates(D of quantitativeentrapment collections at soNGS unit r., 2, or 3 during the 39'mo period from May 1983through August 1986. Collectionsat Unit L are quantitative impingementsamples and at units 2 and 3 include both I quantitative impingementand diversion samples. a indicates samplesthat were usedto compareentrapment at unit l with units 2 andfor 3. b indicates samples that were usedto compareentrapment under full flow operatingconditions at Units I 2 and 3. I Dare UNrf 1 UNIrr2 UNrI3 04 JAN g4a X X 20MAR 84b X x I 18APR 84b x X 24APR 84b x X 25 APR 84b X X I 06 JUN 84b X X 14AUG 84b X x 22AUG 84b X X T 05sEP 84b X x 09 ocr 84b X X r.0 ocT 84b X x 17 oCT 84b x X I 11DEC g4a x X

09 JAN 85a X X I 23 JAN 85a X X 16APR 85b X X X 1.7APR 85b X X X 23 APR 85b X X X I 24APR g5b X X X 30 AI)R g5ab X X X 07 MAY 85b X x I 08 MAY 85b X X 15 MAY 85b X X 04 JUN 85a X X X 05 JUN 85b X X I 25 JUN 85b X X 26 JUN 85ab X x x 02 JUL 854 X X t 16JUL 85b X X X 17JUL 85b x X 23 JUL 85b X X I 24 JUL 85b X X 30 JUL 85b X X 31JUL 85ab X X x 1.4AUG 85b X X I 21AUG 85b X X t I A-7 I I

Table A-1 I page2 ot2 I DATE UNrr 1 Ur.{rr2 UlrrI3

27AUG 85b X x I 28AUG 85b x X 04sEP 85b X X x 12SEP 85b X X I 17 SEP g5ab X X X 15 oCT 85a X X 05 NOV 85a X X I 01JUL 86a X X X 19AUG 86a X X 26AUG 86a X X X I I I I t I I I I I t A-8 I I I TableA-2

Ranks by abundance of speciesat SONGS Units 2 and 3. Rankings are based on the I total number of fish of each species in samples taken concurrently at the 2 units on dates in 1984 and 1985 when both units were operating at full flow (4 Pumps, see I Table A-1). Only the top 20 speciesare ranked.

NUMERICAL RANK -----.-- I SPEcrEs Ur.nr2 UNn3 t northern anchovy 1 1 queenfish ') 3 white croaker 3 2 jacksmelt 4 ?n I salema 5 5 yellowfin croaker 6 7 slough anchovy 7 4 I walleye surfperch 8 10 Pacific pompano 9 11 deepbody anchovy 10 9 I zebra perch 11 L3 white seaperch L2 8 sargo L3 L2 plainfin midshipman L4 L4 t California corbina 15 L6 kelp bass T6 15 barred sand bass T7 T9 I shiner perch 18 L7 white seabass t9 18 I topsmelt 20 6 I I I I I I I A-9 I

Table A-3 I

Ranks of biomass of speciesat SONGS Units 2 and 3. Rankings are based on the total biomass of each species in samples taken concurrently at the 2 units on dates I in 1984 and 1985 when both units were operating at full flow (4 Pumps, see Table A-l). Only the top 20 speciesare ranked. I

BIoMAss RANK ------UNTT2 Ur{rr3 I

queenfish 1 t I northern anchovy 2 4 yellowfin croaker J 3 jacksmelt 4 20 zebraperch 5 7 I Pacificelectric ray 6 9 white croaker 7 2 shovelnoseguitarfish 8 5 I salema 9 14 sargo 10 10 California corbina 11 13 kelp bass t2 11 I barred sandbass t3 18 round stingray L4 L5 spotfincroaker 15 L7 t Pacificpompano 16 T9 bat ray t7 6 white seabass 18 16 I Californiahalibut t9 \2 topsmelt 20 8 I I I I I I I A- 10 t I I I I Table A-4 Results of nonparametric correlations between species rankings at SONGS Units 2 and 3. Rankings are based on total number or biomass of each species in samples taken concurrently at the 2 units on dates in 1984 and 1985 when both units were I operating at full flow (4 pumps). Numbers anil biomass were anallzed for the top 20 species. The null hypothesis, H6, is that there is no correlation, i.e., T = 0. Thus p I < 0.05 indicates that the rankings for Units 2 and 3 are correlated.

I TESTVARIABLE KENDALL,S TAU I NUMBERS, Top 20 Species <0.001 I BIOMASS,Top 20 Species 0.38 20 0.02 I I I I t I I t I I A- 11 I I Table A-5

Results of paired t-tests comparing entrapment at SONGS Units 2 and 3. A two- tailed paired t-test was used to test the hypothesis that entrapment, measured t concunently at the 2 units on dates in 1984 and 1985when both units were operating at full flow (4 pumps, see Table A-1), was not significantly different. Data were Logro (x) transformed before the differences were calculated. Both numbers and I biomass were tested for the 2 most abundant speciesand for all speciescombined. I - T-TESTSTATISTICS TDF P I NUMBERS

queenfish -0.51 34 0.61 I northern anchovy 0.55 v 0.59 Total Fishes -0.43 v 0.67 I BIOMASS I queenfish -0.81 34 0.42 northern anchovy 0.28 34 0.78 Total Fishes -t.62 v 0.11 I I I I I I I I T A- t2 I Table A-6

Dates of 24 hr entrapment samples used to compare the magnitude of entrapment at different flow volumes in Units 2 and 3. Only dates with one unit pumping at fult flow (4 pumps) and the other unit pumping at less than fult flow were used. The factor used to scale entrapment at less than full flow up to the estimated full flow I magnitude is also shown. Results of the analyses are presented in Table A-7.

I UNrI2 UNrr3 # Putvtps FAcfoR # PUMPS FaCron

18 JUL 84 ,: 4 O1AUG84 2 2.0

I 06 MAR 85 1..33 13 MAR 85 r.33 20 MAR 85 L.33 I 27 MAR 85 2.0 O2APR85 2.0 O3APR85 2.0 1OAPR85 2.0

OTJAN86 1.33 08 JAN 86 L.33 t 26FEBft6 2.0 04 MAR 86 2.0 05 MAR 86 2.0 I 11MAR 86 ,: 03 JUN 86 I.JJ I O4JUN86 I.JJ t I I I I A-13 I

table A-7 I

Results of paired t-tests comparing the magnitude of entrapment in one new unit operating at full flow volume (4 pumps) with the magnitude of entrapment in the other new unit which was I concurrently operating at less than fult flow volume. To test the hypothesis that the magnitude of entrapment is directly proportional to flow volume, entrapment in the unit operating at less than full flow volume was adjusted to full flow level using the factor listed in Table A-6. A two-tailed paired t- I test was then used to test the hypothesis that, when adjusted, the magnitude of entrapment measured concurrently at the 2 new units was not significantly different. Data were Logro (X) transformed before the differences were calculated. Shown are the means (SE) of the differences of the transformed data (full llow - adjusted to full tlow). Both numbers and biomass were tested. I I No. oF ._--- NUMBER oF INDIVIDUAIS - BroMAss --- SPEcrEs/ PAIRED Gnoup SAMPLES MEAN SE T P MEAN SE T I queenfish 17 4.081 0.131 4.62 0J5 I white croaker l7 0.018 0.193 0.09 0.93 0513 0.2& walleye surfperch 10 0.055 0.151 0.% 0.73 l northern anchovy t6 4Ju 0.251 {.65 0.52 4.274 0.270 0.33

Total Fishes 17 4.144 0.141 -1.02 0.32 4.172 I

Total fishes minus t7 4.105 o.tu -0.85 0.41 4.W2 O.L?A 4;14 0.47 northem anchovy I I I I I I I I A" 14 t I

I TableA-8

Results of paired t-test comparing the number of fish entrapped at Unit 1 operating I at full flow, with the number of fish entrapped at a new unit (Unit 2 or 3) concurrently operating at full llow. A two-tailed paired t-test was used to test the hypothesis that entrapment at the new unit is 25 times entrapment at Unit 1. The I number of lish entrapped at Unit I was multiplied by 25 and the data were Logro (x * 1) transformed before the differences were calculated. Shown is the mean (SE) of the difference of the transformed data [Logro (new unit) - Logro (Unit 1 x 2.5)]. The mean difference was used to calculate the actual relationship betweenthe magnitude I of entrapment at Unit 1 and at Units 2 & 3. I No. oF PAIRED MEAN SE T I SAMPLES

I 15 0.4899 0.1680 2.92 0.0113 I Calculations for relationship between magnitude of entrapment at Unit 1 and at Units 2 & 3. I l,ogro (Unit 2 or 3) - hgro (Unit 1 x2.5) = 0.2$899 Unit 2 or 3 = 7.7 (Unit 1) I Unitl=Unit2+Unit3 L5.4 I I t I I I I I A- 15 Figure A-1: Histogramof the size distributionof large queenfish(2 100mm SL). Datawere pooled over 15sample dates for SONGSUnit 1 and Units2 &3. Fishwere divided into 10 mm lengthclasses. n = total numberof fish sampledin the differentunits.

A- 16 I I

I SIZE DISTRIBUTIONOFQUEENFTSH )100mm 25.0 I UNIT1 I 20.0 n: 417 I 15.0 I 10.0 l 5.0 0.0 I 105 115 125 135 14s 155 165 175 )185 zF td () I E, l4J (L

I 25.0 UNITS2 & n=531 I 20.0

I 15.0

I 10.0

I 5.0

I 0.0 105 115 125 135 145 155 165 175 )185 T LENGTH T I A- L7 This pageintentionally left blank.

A- 18 I I APPENDIX B I I Data Sources for Tables Abbreviations: DeM 87 = DeMartini, E.E. and UCSB Staff. 1987. The effectsof operationsof the San Onofre Nuclear GeneratingStation on fish. Final Report submitted to the Marine Review Committee, Inc., I December1987.

TR C = This Report - Technical Report C. Entrapment of I juvenileand adult fi^shat SONGS.

I Table 1.: List of datesof entrapmentcollections at SONGSUnits 1,2, or 3. I DaraSounce: AppendixF, Table 1 in DeM 87. Table2: List of dateson which heat treatmentsoccurred at SONGSUnits 1.. I 2, or 3. I DaraSouncB: Appendix F, Table 3 in DeM 87. Table3: Number'J.,2, of full-flow operational daysper month for SONGS Units t and3. Dare Sounce: AppendixF, Tables4, 5, and 6 in DeM 87. - combinedthe 3 tables - summed all days over the 39 month period and recalculated I percentfull pumpingfor the period.

I Table 4: Resultsof regressions-and of percentqueenfish mortality vs. abundance of queenfish total fish in pens. I DareSounce: Table 15in DeMartini et al.1986. VARIABLE SouRceVaruasle N n I R2 correlation coefficient (r) squared t P P I I I B-1 I I Table 5: List of speciescollected in samplesat SONGSUnits 1,2 and3. 'l-1, DeraSouncr: Common names of all specieslisted in Tables 12, L3, 14, AppendixG, Tables1-16 and AppendixH, Tables1-4 in DeM 87. I scientific names from Guide to the Coastal Marine Fishes of California,Miller andl*a, L972. t

Table 6: \uryber, biomassand mean weight per fish for fish IMPINGED at Units 2 & 3. I DaraSouncp: AppendixH, Table 1 in DeM 87. I VARIABLE SOURCEVARIABLE Number Total Number Impinged Weight Total Weight Impinged Mean Wt./Fish Weight/Number I

Table 7: \upber, biomassand meanweight per fish for fish DIVERTED at I Units2 &3. DanaSouncn: AppendixH, Table 1 in DeM 87. I VAruABLE SOURCEVARIABLE Number Total Number Returned Weight Total WeightReturned I Mean Wt. per Fish Weight/Number

Table8: Averagebody weight and size classificationfor fishes entrappedat I SoNdS Uniis 2 &-3. DareSounce: AppendixH, Table2 in DeM 87. I I I I I I T B-2 t I I Table 9: \urybe1r_biomassand mean weight per fish for fish impinged duringHEAT TREATMENTS at SONGSUnits 2 & 3. I DareSouncn: AppendixG, Tablds11, 13 & 15in DeM 87.

VARIABLE SOURCEVARIABLE I Number sum of Total Fish Number in Tables11. 13 & 15 Weight sum of Total Fish Weight in Table 1.1, 13 & 15 I Mean Wt. per Fish Weight/Number

I Table 10: ljur.nbe_rr_biqqq;sand mean weight per fish for fish impinged during HEAT TREATMENTS at SONGSUnit 1. I DeraSouncr: AppendixG, TableslZ & 14in DeM 87. VARIABLE SoURcEVARIABLE Number sum of Total Fish Number I in Tables12 & 1,4 Weight sum of Total Fish Weight in Tables12 & L4 t MeanWt. per Fish Weight/Number t I T I I I t I I I B-3 I I Table 1L: Annual estimatesof entrapmentat SONGS Unit 1 and Units 2 & 3. DataSouncs: For speciesand groups t

Spnqrson ANNUAL EsflNaeres FoR NUMBERAND Blouass GRoUP UNrr 1 uNms2& 3 I queenfish estimated from Table1L, northern anchow Units2 &3 - DeM 87 white croaker seeMethods. I walleyesurfperch Table11, Table LL, Pacific electric rav Dem 87 DeM 87 t white seaperch sumof: Table 11 Pacificpdmpano impinged+ diverted DeM 87 from DeM 87 I plus heattreatment from Table 10,TR C. (L2/39 X Numberor Weight) I jacksmelt sumof: sum of: yellowfin croaker impinged+ diverted impinged + diverted salema from SASprogram from SAS program I kelp bass ANI-SU187(fish ANI-SMV87 (fish barred sandbass project E disk) project E disk) California corbina plus heat treatment plus heat treatment T spotfin croaker Table 10,TR C. Table 10,TR C. black croaker (L2/39 X Number (12/39 X Number topsmelt or Weight) or Weight) gruruon I

Total Fishes calculatedas: Table Ll., Total Fishes(from DeM 87) DeM 87 I minus queenfish,northern anchow & white croaker from D-eM87 I plus estimatesfor queenfish, northern anchow & white croakershown a6ove I all other species summedover 17 summedover 17 combined specieslisted specieslisted and subtractedthe and subtractedthe I sum from Total Fishes sum from Total Fishes I I I B-4 I I I Table L2: Annual estimatesof the numberof fish either killed in heat I treatments,impinged on travellingscreens or divertedto the FRS. (A) For lT lndividual Species I (a) Heat treatment= (12/39)X Numberin Table 9 (TR C) for eachspecies (U) Ptfe$ed = KNumberfor Units 2 &3 in Table 11(TR C)) - (Heat treatment in Table 12 (TR C))l X [(PercentNumber Returned in Afpendix H, Table 1 I (DeM 87)/1001

(c) fmpi4gs6 = .(Numberfor Units 2 & 3 in Table 11 (TR C)) - (Heat treatment I in Table 12 (TR C)) - (Divertedin Table 12 (TR C))

I (B) For AII Other SpeciesCombined (a) $_ryttreatment =. (L2/39) X (sum of all speciesin Table 9 (TR C)) except I 17individual species (b) Pryg1tgd= l.Qlumberfor Units 2 &3 in Table 11 (TR C)) - (heat treatment in Table 12 (IR C))l X [proportiondiverted]; Proirortion diverted = D./(I. lD" ry!.er9D. = sum o-fTotal Number Reiurneii in AppendixH, Tabie'1 I (O9ry187), for a[species exceptthe 17 individualspecies Table 12 ('IR C); and I. = sum of Tolal Numbef Impingedin AppendixH, Table 1 (DbM 87), t for all speciesexcept the 17indiviciual-species in taUte 12 (TR C).' t (C) Total Fish Sum of the 16 individual speciesand all other speciescombined for heat I treatment,impinged and diverted. (D) Small,Medium, LargeFish Categories I 1. dMded "all other speciescombined: into sizeclasses (see method below) 2. qqsignedeach of 17 individual speciesto appropriate size class(Table 8 TR I c) I 3. summedover size classes I I I I B-5 t I Methodfor dividingnall other species combined" into sizeclasses: (a) for impingedand diverted t i) in Appendi"_ryn,Table1 (DeM 87),eliminated the 17individual species in Table 1? (TR_C.)und then placeil all remaining speciesin size c'lasses basedon Table 8 (TR C) t ii) summedTotal Number Impinged (Appendix H, Table 1.,DeM 87) for each size classand calculated-the'pitiportioncomprised by each'size class(large = 0.034,medium = 0.074,srirall = 0.892). I iii) ymmed Total NumberReturned (Appendix H, Table L,DeM 87) (note: this is diverted)for eachsize class airb calculaiedproportion coririrised' I by eachsize class (large = 0.220,medium = 0.068,smdtt = 0.712) iv) to calculate the number impinged or diverted in each size class, the proportions for each classcalculated in (ii) and (iii) were multiplied be I the numberfor "all other speciescombinedt'for impinged or diveited I (b) for heattreatment

i) qs.signedspecies in Table 9 (TR C) to sizeclasses (based on Table 8, TR C) I

ii) summednumber in Table 9 (TR C) folg:aqh size class[excluding the 17 specieslisted individually in Table 12(TR C)l I iii) calculatedthe propoftion of the total in each size class(large = 0.582, medium = 0.033,small = 0.385) I iv) to calculatethe number killed in heat treatmentsin each size class,the numberof fish killed in heat treatmentsfor "all other speciescombined" wasmultiplied by the proportionsfor eachsize class in (iii) T

(E) Percentdiverted = Diverted/ (Heat treatment * impinged + diverted) X 100, for all categories I T I I I I B-6 I I

I Table L3: Annual estimatesof the biomassof fish eitherkilled in heat treatments,impinged on travellingscreens or divertedto the FRS. t Methodsfor calculatingbiomasswere the sameas for calculatingnumbers in Table 12 (above). I Proportionu;gd..fo.r dividing the "all other speciescombined" category into size classes(see (a) ii, (a) iii, an-db (iii) in Table 12method above) t ------PRopoRToNoF BroMAsslN Eacg SrzBCress I SIZE CI-A,SS HE{TTREI\TMENT JMpINcED DIvERTED small 0.014 0.131 0.02() medium 0.016 0.179 0.050 I large 0.970 0.690 0.910 t Table 14: Mortality of fish dischargedfrom FRS. DaraSouncn: Appendix H, Table 1 in DeM 87. Vomortalitv for sizeclasses: small = weightedaverage of white croaker,queenfish, white I seaperch,shiner surf perch(species without Controlsand northern anchovywere excluded) medium= weightedaverase of all 8 medium.species I large = weightEdaverage 5f att tO largespecres

I Table 15: mortalityof smalland large queenfish discharged from FilS:*

I DaraSouncn: AppendixH, Table 4 in DeM 87. I Table 16: Percentefficiency for numberand biomass of fish for FRS. DaraSounce: %odiversion number from Table 12 (TR C) t Vodiversion biomass from Table 13 (TR C) 7osurvivorship FRS transDortfrom Table 14 (TR C). (% survivorship= 1,- Vorirortality due to FRS) J Voefhciency number = (7o diveriion number)'X (7o survivorship FRS) Voefficiency biomass = (7o diversionbiomass) X (Vosurvivorship I FRS) t I T B-7 AppendixTables

Table A-1 P{.r of_quantitativeentrapment samples, Appendix F, TablesL & 2,DeM 87

Table A-2, SASprogram KDTCCU23.SASon Fish Project Disk E A-3, A-4

Table A-5 SASprogram U23TTEST.SASon Fish Project Disk E Table ,A-6 Datesof 24 hr entrapmentsamples used to comparethe magnitude of entrapmentat differentflow volumesin Units 2 & 3 Appendix F, Table 8, DeM 87 Table A-7 SASprogram FLOWTSTI.SAS on Fish Project Disk E Table A-8 SASprogram TTPRUNT2.SAS on Fish Project Disk E

B-8