ML17229B109

1998 Annual Environ Operating Rept for St Lucie Unit 2.

ML17229B109
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Issue date:	12/31/1998
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FLORIDAPOWER4LIGHTCOMPAZ'WST.LUCIEUIGT2Al.'VKJAL ElVVIRONME<NTAL OPERATING REPORT1998~gNGagFLORIDAPOWER8rLIGHTCOMPANYJUNOBEACH,FLORIDAQUANTUMRESOURCES, INC.PALMBEACHGARDENS,FLORIDAi9905040ii9.990428>PDRADOCK050003898PDRJ ENVIRONMENTAL OPERATING REPORTTABLEOFCONTENTSPARTI1.0Executive Summary1.1Introduction 1.2TurtleNestingSurvey1.3IntakeCanalMonitoring

2.0 Introduction

lv2.1Background 2.2AreaDescription 2.3PlantDescription 3.0Turtle3.1Introduction 3.2Materials andMethods3.2.1NestingSurvey3.2.2IntakeCanalMonitoring 3.3ResultsandDiscussion 3.3.1NestingSurvey3.3.1.11998Loggerhead NestingSummary3.3.1.2SpatialDistribution ofLoggerhead TurtleNests63.3.1.3Long-Term TrendsinLoggerhead TurtleNesting73.3,1.4SeasonalPatternsofLoggerhead TurtleNesting7,3.3.1.5Predation onLoggerhead TurtleNests3.3.1.61998GreenandLeatherback NestingSurvey83.3.1.7TrendsinGreenandLeatherback TurtleNesting9 3.3.2IntakeCanalMonitoring 3.3.2.11998CanalCaptureSummary10103.3.2.2RelativeAbundance andTemporalDistribution 103.3.2.3SizeClassDistributions 3.3.2.4SexRatios3.3.2.5CaptureEfficiencies 3.3.2.6BarrierNetMaintenance 3.3.2.7RelativeCondition 3.3.2.8Mortalities 3.3.2.9Recapture Incidents 3.3.3Summary4.0Literature Cited5.0Figures6.0Tables1212131414171932PARTII1.0Introduction

2.0 SeaTurtleMonitoring

andAssociated Activities

3.0 TaproggeCondenser

TubeCleaningSystemOperation 4.0OtherRoutineReports5.0TableandFigures3636363738

1.0 EXECUTIVE

SUlV84ARY

1.1INTRODUCTION

TheSt.LuciePlantisanelectricgenerating stationonHutchinson IslandinSt.LucieCounty,Florida.Theplantconsistsoftwonuclear-fueled 850netMWeunits;Unit1wasplacedon-lineinMarch1976andUnit2inApril1983.Thisdocumenthasbeenpreparedtosatisfytherequirements contained inAppendixB,Environmental Protection Plan(EPP),toSt.LucieUnit2FacilityOperating LicenseNo.NPF-16.Thisreportprimarily discusses environmental protection activities relatedtoseaturtlesasrequiredbySubsection 4.2oftheEPP.Otherroutineannualreporting requirements areaddressed inVolume2.1.2TURTLENESTINGSURVEYSincemonitoring beganin1971,therehavebeenconsiderable year-to-year fluctuations inseaturtlenestingactivityonHutchinson Island.However,datacollected through1998haveshownnolong-term reductions innestingontheisland.Relatively highnestingduringrecentyearsmayactuallyreflectanincreaseinthenumberofnestingfemalesinthestudyarea.Onasmallerscale,powerplantoperation hashadnosignificant effectonnestingneartheplant.Lownestingactivityin1975andagainin1981-1983 inthevicinityoftheplantwasattributed tonighttime construction activities associated withinstallation ofplantintakeanddischarge structures.

Nestingreturnedtonormalorabovenormallevelsfollowing bothperiodsofconstruction.

During1991,daytimeconstruction activities associated withvelocitycaprepairshadnoapparenteffectonnesting.Formalrequirements toconductnestingsurveysexpiredin1986,butthisprogramhasbeencontinued through1998withagreement fromfederalandstateagencies.

In1998,thecontinuation ofthenestingsurveyprogramwasmandatedaspartofthebiological opinionandincidental takestatement issuedbytheNationalMarineFisheries Service.1.3INTAKECANALMONITORING Sinceplantoperation beganin1976,6086seaturtles(including recaptures) representing fivedifferent specieshavebeenremovedfromtheintakecanal.Themajorityoftheturtlescaptured(59percent)wereloggerheads.

Differences inthenumbersofturtlesfoundduringdifferent monthsandyears,including dramaticincreases ingreenturtlecapturesinrecentyears,havebeenattributed primarily tonaturalvariation intheoccurrences ofturtlesinthevicinityoftheplant,ratherthantooperational influences oftheplantitself.Themajorityofturtlesremovedfromtheintakecanal(about97percent)werecapturedaliveandreleasedbackintotheocean.Ongoingevaluations andimprovements tothecanalcaptureprogramhavesubstantially reducedmortalities ofentrapped seaturtlesduringrecentyears.Turtlesconfinedbetweenthebarriernetandintakeheadwalls typically resideinthecanalforarelatively shortperiodpriortocapture,andmostareingoodtoexcellent condition whencaught.Animproveddesignbarriernetcompleted inJanuary1996isexpectedtofurtherreducetheresidence timesandpotential formortalities toseaturtlesintheintakecanalsystem.

2.0INTRODUCTION

2.1BACKGROUND Tliisdocumenthasbeenpreparedtosatisfytherequirements contained inAppendixB,Environmental Protection Plan,toSt.LucieUnit2FacilityOperating LicenseNPF-16.St.LucieUnits1and2usetheAtlanticOceanasasourceofwaterforonce-through condenser cooling.Since1971,thepotential environmental effectsresulting fromtheintakeanddischarge ofthiswaterhavebeenthesubjectofFPLsponsored bioticstudiesatthesite.Jurisdiction forseaturtlestudiesiswiththeNRC,whichisconsidered tobetheleadfederalagencyrelativetoconsultation undertheEndangered SpeciesAct.Previousresultsdealingwithseaturtlestudiesarecontained infourteenannualenvironmental operating reportscoveringtheperiodfrom1983through1997.Tliisreportdescribes the1998environmental protection activities relatedtoseaturtles,asrequiredbySubsection 4.2oftheSt.LucieUnit2Environmental Protection Plan.2.2AREADESCRIPTION TheSt.LuciePlantislocatedona457-hectare siteonHutchinson IslandonFlorida's EastCoast(Figures1and2).Theplantisapproximately midwaybetweentheFt.PierceandSt.LucieInlets.ItisboundedontheEastSidebytheAtlanticOceanandontheWestSidebytheIndianRiverLagoon.Hutchinson Islandisabarrierislandthatextends36kmbetweeninletsandattainsitsmaximumwidthof2kmattheplantsite.Elevations approach5matopdunesbordering thebeachanddecreasetosealevelinthemangroveswampsthatarecommononmuchofthewesternside.TheAtlanticshoreline ofHutchinson Islandiscomposedofsandandshellhashwithintermittent rockypromontories protruding throughthebeachfacealongthesouthernendoftheisland.Submerged coquinoid rockformations parallelmuchoftheislandofftheoceanbeaches.Theoceanbottomimmediately offshorefromtheplantsiteconsistsprimarily ofsandandshellsediments, TheFloridaCurrent,whichflowsparalleltothecontinental shelfmargin,beginstodivergefromthecoastline atWestPalmBeach.AtHutchinson Island,thecurrentisapproximately 33kmoffshore.

Oceanicwaterassociated withthewesternboundaryofthecurrentperiodically meandersovertheinnershelf,especially duringsummermonths.2.3PLANTDESCRIPIION TheSt.LuciePlantconsistsoftwo850netMWenuclear-fueled electricgenerating unitsthatusenearshoreoceanwatersfortheplant'sonce-through condenser coolingwatersystem.Waterfortheplantentersthroughthreesubmerged intakestructures locatedabout365moffshore(Figure2).Eachoftheintakestructures isequippedwithavelocitycaptominimizefishentrainment.

Fromtheintakestructures, thewaterpassesthroughsubmerged pipes(two3.7mandone4.9mindiameter) underthebeachanddunesthatleadtoa1,500meterlongintakecanal,whichtransports watertotheplant.Afterpassingthroughtheplant,theheatedwaterisdischarged intoa670meterlongcanalthatleadstotwoburieddischarge pipelines.

Thesepassunderneath thedunesandbeachandalongtheoceanfloortothesubmerged discharges, thefirstofwhichisapproximately 365moffshoreand730mnorthoftheintake.

3.1INTRODUCTION

Hutchinson Island,Florida,isanimportant rookeryfortheloggerhead turtle,Carettacaretta,andalsosupportssomenestingofthegreenturtle,Chelonia~mdas,andtheleatherhack I,D~hl'.Sdfdlpllhpi.'Ihfd&

government hasclassified theloggerhead turtleasathreatened species.Thefederalgovernment endangered specieslistsincludetheleatherback turtleandtheFloridanestingpopulation ofthegreenturtle.IthasbeenanFPLgoalthattheSt.LuciePlantwouldnotadversely affecttheHutchinson Islandrookery.Becauseofthisconcern,FPLhassponsored monitoring ofmarineturtlenestingactivity, ontheislandsince1971.Daytimesurveystoquantifynesting,aswellasnighttime turtletaggingprograms, wereconducted inoddnumberedyearsfrom1971through1979.Duringdaytimenestingsurveys,nine1.25km-longsurveyareasweremonitored fivedaysperweek(Figure3).TheSt.LuciePlantbeganoperation in1976;therefore, thefirstthreesurveyyears(1971,1973,and1975)werepre-operational.

Thoughthepowerplantwasnotoperating during1975,St.LuciePlantUnit1oceanintakeanddischarge structures wereinstalled duringthatyear.Installation ofthesestructures includednighttime construction activities conducted offshorefromandperpendicular tothebeach.Construction hadbeencompleted andtheplantwasinfulloperation duringthe1977and1979surveys.Amodifieddaytimenestingsurveywasconducted in1980duringthepreliminary construction oftheoceandischarge structure forSt.LucieUnit2.Duringthisstudy,fourofthepreviously established 1.25km-longsurveyareasweremonitored.

Additionally, eggsfromturtlenestspotentially endangered byconstruction activities wererelocated.

Everyyearfrom1981through1998,36one-km-long surveyareascomprising theentireislandweremonitored sevendaysaweekduringthenestingseason(Figure3).Beginning in1994,thesouthernhalfoftheislandhasbeensurveyedbyEcological Associates ofJensenBeach,Florida,andtheirdataisincludedinthisreport.TheSt.LucieUnit2discharge structure wasinstalled duringthe1981nestingseason.Offshoreandbeachconstruction oftheUnit2intakestructure proceeded throughout the1982nestingseasonandwascompleted neartheendthe1983nestingseason.Construction activities associated withinstallation ofbothstructures weresimilartothoseconducted whenUnit1intakeanddischarge structures wereinstalled.

Eggsfromturtlenestspotentially threatened byconstruction activities wererelocated.

During1991,anothermajoroffshoreconstruction projectwasundertaken toreplacedamagedvelocitycapsonthethreeintakestructures.

Alargeelevatedplatform, fromwhichrepairactivities wereconducted, waserectedaroundthethreestructures.

Construction occurredthroughout thenestingseason.However,incontrasttopreviousoffshoreprojects, workwasrestricted almostentirelytodaylighthours,nighttime lightingoftheworkareawasminimal,andnoequipment ormaterials wereusedonthebeach.Aseaturtleprotection planimplemented insupportoftheprojectincludedcagingofnestsalonga1,500metersectionofbeachwestoftheplatformandreleaseofhatchlings tounaffected areastothenorthandsouth.Thisplanwas intendedtomitigateanynegativeeffectspotentially resulting fromrequiredsafetyandnavigational lightingonandneartheplatform.

Requirement 4.2.1oftheSt.LucieUnit2AppendixBEnvironmental Protection Planwascompletewithsubmission ofthe1986nestingsurveydata(ABI,1987).Thenestingsurveywascontinued voluntarily through1998withagreement fromfederalandstateagencies.

Resultsarepresented inthisreportanddiscussed inrelationtopreviousfindings.

Inadditiontomonitoring seaturtlenestingactivities andrelocating nestsawayfromplantconstruction areas,removalofturtlesfromtheintakecanalhasbeenanintegralpartoftheSt.LuciePlantenvironmental monitoring program.Turtlesenteringtheoceanintakestructures areentrained withcoolingwaterandrapidlytransported throughtheintakepipesintoanenclosedcanalsystemwheretheymustbemanuallycapturedandreturnedtotheocean.Sincetheplantbecameoperational in1976,turtlesentrapped intheintakecanalhavebeensystematically

captured, measured, weighed,tagged,andreleased.

Previouspublications andtechnical reportshavepresented findingsofthenestingsurveys,nestrelocation activities andcanalcaptureprogram(ABI,1994)(Quantum, 1995,1996,1997,1998).Resultsofstudiestoassesstheeffectsofthermaldischarges onhatchling swimmingspeedhavealsobeenreported(ABI,1978).InJuly1994,responsibility forseaturtleresearchandconservation activities wastransferred fromEcological Associates, Inc.(formerly AppliedBiology,Inc.)toQuantumResources, Inc.Methodologies employedinboththenestingsurveysandcanalcaptureoperations remainedessentially unchanged sothatdatacollected in1994throughthepresentaredirectlycomparable topreviousyear'sdata.Thepurposeofthisreportisto:1)present1998seaturtlenestingsurveydataandsummarize observedspatialandtemporalnestingpatternssince1971,2)documentandsummarize predation onturtlenestssince1971,and3)present1998canalcapturedataandsummarize comparable datacollected since1976.3.2MATERIALS ANDMETHODS3.2.l~tl'Methodologies usedduringpreviousturtlenestingsurveysonHutchinson Islandweredescribed inearlierreports(ABI1994).Methodsusedduringthe1998surveyweredesignedtoallowcomparisons withthesepreviousstudies.In1998,onlyaicasA-SweresurveyedbyQuantumResources biologists (Figure3).DatasuppliedbyEcological Associates, Inc.areusedtoprovidewholeislandnestingtotalsinFigures6,8,and9.FromMarch24,1998throughApril14,1998,severalpreliminary nestsurveyswereconducted alongHutchinson IslandinareasA-S.NonestingwasrecordedinareasA-Spriortothebeginning offormalnestingsurveysonApril15,1998.FromApril15,1998throughSeptember 8,1998,nestsurveyswereconducted onadailybasis.ThelastnestrecordedinareaA-SwasonSeptember 7,1998.Biologists usedsmalloff-roadmotorcycles tosurveytheislandeachmorning.Newnests,non-nesting emergences (fa'Isecrawls),andnestsdestroyed by predators wererecordedforeachofthe1-km-long surveyareasA-S(Figure3).The1.25-km-longsurveyareasthatwereestablished inearlierstudiesalsoweremonitored socomparisons couldbemadewithpreviousstudies.Datacollected frombeachnestingsurveyswerereportedtotheFloridaDepartment ofEnvironmental Protection (FDEP)aspartoftheFDEPIndexNestingBeachSurvey.Inacooperative effort,datafromstrandedturtlesfoundduringbeachsurveyswereroutinely providedtotheFloridaDepartment ofEnvironmental Protection andtheNationalMarineFisheries Service(NMFS)throughtheSeaTurtleStranding andSalvageNetwork.3.2.2IntakeCanalMonitorin Mostturtlesentrapped intheSt.LuciePlantintakecanalwereremovedbymeansoflarge-meshtanglenetsfishedneartheintakecanalheadwalls attheextremeeasternendoftheintakecanal(Figure2).Netsusedduring1998werefrom30to40minlength,3to4mdeepandcomposedof40cmstretchmeshmultifilament nylon.Largefloatswereattachedtothesurface,andunweighted linesusedalongthebottom.Turtlesentangled inthenetsgenerally remainedatthewater'ssurfaceuntilremoved.Sinceitsinception in1976,thecanalcaptureprogramhasbeenundercontinual reviewandrefinement inanattempttominimizebothentrapment timeandinjuries/mortalities toentrapped seaturtles.PriortoApril1990,turtlenetswereusuallydeployedonMondaymorningandretrieved onFridayafternoon.

Duringperiodsofdeployment, thenetswereinspected forcapturesatleasttwiceeachday(mornings andafternoons).

Additionally, St.LuciePlantpersonnel checkedthenetsperiodically, andbiologists werenotifiedimmediately whenacapturewasobserved.

Seaturtlespecialists, thatretrievecapturedturtlesfromtheplantintakecanalsystem,wereoncall24hoursaday.Beginning April1990,afterconsultation withNMFS,netdeployment wasscaledbacktodaylighthoursonly.Concurrently, surveillance oftheintakecanalwasincreased andbiologists remainedonsiteforthedurationofeachday'snettingactivities.

Thismeasuredecreased responsetimeforremovalofentangled turtlesfromnetsandprovidedanopportunity toimprovedailyassessments ofturtlelevelswithinthecanal.Recordsofdailycanalobservations werecomparedwithcapturedatatoassesscaptureefficiencies.

In1978,abarriernetattheA1ABridgewasconstructed toconfineturtlestotheeasternmost sectionoftheintakecanal,wherecapturetechniques havebeenmosteffective.

Thisnetisconstructed oflargediameterpolypropylene ropeandhasameshsizeof20.3cmx20.3cm.Acableandseriesoflargefloatsareusedtokeepthetopofthenetabovethewater'ssurface,andthebottomisanchoredbyaseriesofconcreteblocks.Thenetisinclinedataslopeof1:1,withthebottompositioned upstreamofthesurfacecable.Thisreducesbowinginthecenterandminimizes theriskofaweakorinjuredturtlebeingpinnedunderwater bystrongcurrents.

Inthepast,theintegrity ofthebarriernetwasoccasionally compromised, andturtleswereabletomovewestofA1A.Theseturtleswerefurtherconstrained downstream byanunderwater intrusion detection system(UIDS)consisting, inpart,ofalargebarrierpositioned perpendicular tothenorth-south armofthecanal(Figure2).TheUIDSsecuritybarrierhasameshsizeof22.9cmx22.9cm.Priortocompletion oftheUIDSinDecember1986,turtlesunconfined bythe A1AbarriernetwereusuallyremovedfromthecanalattheintakewellsofUnits1and2(Figure2).Theretheywereretrieved bymeansoflargemechanical rakesorspecially designednets.Following construction oftheUIDSbarrier,allbutthesmallestindividuals wereunabletoreachtheintakewells.Improvements madetotheA1Abarriernetduring1990haveeffectively confinedallturtleslargerthan32.5-cmcarapacelength(28.7-cmcarapacewidth)totheeasternendofthecanal.Inresponsetothelargenumbersofsmallturtlesencountered intheintakecanalinrecentyears,animproveddesign,smallmeshbarriernetwaserectedeastoftheA1Abarriernet,Construction was,complete inJanuary1996.Thisimprovedbarriernetisdesignedtoconfineallturtleswithacarapacewidthgreaterthan18cmtotheextremeeasternportionoftheintakecanal.Formaldailyinspections oftheintakecanalweremadetodetermine thenumbers,locations, andspeciesofturtlespresent.Surfaceobservations wereaugmented withperiodicunderwater inspections, particularly inandaroundthebarriernets.Inadditiontotheuseoftanglenets,dipnetsandhandcapturesusingsnorkelandSCUBAwerealsoemployed.

Longhandleddipnets,employedfromsmallboats,thecanalbanksandheadwallstructures weremoderately effective incapturing turtleswithcarapacelengthsofabout30cmorless.Diverswereemployedtohandcaptureturtleswheneverunderwater visibility permits,andthistechnique hasprovenhighlyeffective inthecaptureofturtlesofallsizes,particularly lessactiveindividuals oftenfoundpartially buriedinthesedimentinthevicinityofthebarriernets.Handcaptureeffortshavehadasignificant impactinreducingentrapment timesforturtlesintheintakecanal.Regardless ofcapturemethod,allturtlesremovedfromthecanalwereidentified tospecies,measured, weighed,taggedandexaminedforoverallcondition (wounds,abnormalities, parasites, etc.).Beginning inJuly1994,allturtlescapturedhavebeenphotographed dorsallyandventrally priortorelease,andthephotographs retainedforfuturereference.

Healthyturtleswerereleasedintotheoceanthesamedayofcapture.Sickorinjuredturtlesweretreatedandoccasionally heldforobservation priortorelease.Whentreatment waswarranted, turtlesweretransported toanapprovedrehabilitation facility.

Resuscitation techniques wereusedifaturtlewasfoundthatappearedtohavediedrecently.

Beginning in1982,necropsies wereconducted ondeadturtlesfoundinfreshcondition.

FloridaPower&LightCompanyandQuantumResources, Inc.continued toassistotherseaturtleresearchers in1998.Sincetheprogrambegan,data,specimens and/orassistance havebeengiventotheFloridaDepartment ofEnvironmental Protection, NationalMarineFisheries Service,USFishandWildlifeService,USArmyCorpsofEngineers, Smithsonian Institution, SouthCarolinaWildlifeandMarineResources

Division, CenterforSeaTurtleResearch(University ofFlorida),

FloridaAtlanticUniversity, University ofCentralFlorida,TexasAEcMUniversity, University ofRhodeIsland,University ofSouthCarolina, University ofIllinois, University ofGeorgia,VirginiaInstitute ofMarineScience,WesternAtlanticTurtleSymposium, SouthAtlanticFisheryManagement Council,FloridaMarineFisheries Commission, HarborandBranchOceanographic Institution andtheNationalResearchCouncil.

3.3RESULTSANDDISCUSSION 3.3.1N~iS3.3.1.11998LoerheadNestinSummaIn1998,7962loggerhead turtlenestswererecordedinthe36one-kilometer segmentscomprising Hutchinson Island.Thisfigureisinaccordance withageneralincreaseinloggerhead turtlenestingonHutchinson Islandsincesurveysbeganin1971,althoughsignificant yeartoyearfluctuations areevident.loggerhead nestsandemergences forsurveyareasA-Sispresented inFigure4.3.3.1.2SatialDistribution ofLoerheadTurtleNestsFrom1981through1998,36one-km-long segmentscomprising theisland'scoastline havebeensurveyed.

Thedistribution ofnestsamongthese36surveyareashasshownanincreaseinnestingfromnorthtosouthalongthenorthernhalfoftheisland(ABI,1987,1994).Alongthesouthernhalfoftheislandtherehasbeeneithernogradientoragradientofdecreasing nestingfromnorthtosouth.Thoughbeachdynamicsmaysometimes affecttheselection ofnestingsitesbyloggerhead turtles,relationships betweenspatialnestingpatternsandspecificenvironmental conditions areoftendifficult toestablish becauseoftheinterrelationship ofthefactorsinvolved.

Notallventuresontothebeachbyafemaleturtleculminate insuccessful nests.These"falsecrawls"(non-nesting emergences) mayoccurformanyreasonsandarecommonlyencountered atotherrookeries.

DavisandWhiting(1977)suggested thatrelatively highpercentages offalsecrawlsmightreflectdisturbances orunsatisfactory nestingbeachcharacteristics.

Therefore, certainfactorsmayaffectaturtle'spreference toemergeonabeach,whileotherfactorsmayaffectaturtle'stendencytonestafterithasemerged.Anindex,whichrelatesthenumberofneststothenumberoffalsecrawlsinanarea,isusefulinestimating thepost-emergence suitability ofabeachfornesting.Inthepresentstudythisindexistermed"nestingsuccess"andisdefinedasthepercentage oftotalemergences thatresultinnests.loggerhead nestingsuccessforareasA-Sin1998ispresented inFigure5.Historically, thepatternofloggerhead emergences ontheislandhasgenerally paralleled thedistribution ofnests(ABI,1987,1994).Incontrast, nestingsuccessbyloggerheads alongtheislandhastypically lackedgradients (ABI,1987,1994).Thus,therelatively highnumbersofloggerhead nestsobservedincertainareasareusuallyaresultofmoreturtlescomingashoreinthoseareasratherthanofmorepreferable nestingconditions beingencountered bytheturtlesaftertheyemerged.Avarietyofenvironmental factors(i.e.,offshorebottomcontours, distribution ofreefs,typeandextentofdunevegetation, andhumanactivityonthebeachatnight)mayeffectloggerhead turtleemergence patternsandseveralhavebeenreportedtoaffectemergence patternsonHutchinson Island(ABI,1988,1989).Undoubtedly, acombination offactorsaccountsfortheoveralldistribution ofemergences andtherefore theoverallnestingpatternontheisland.NestingsurveysonHutchinson Islandwereinitiated inresponsetoconcernsthattheoperation oftheSt.LuciePlantmightnegatively impactthelocalseaturtlerookery.Previousr

analysis, usinglog-likelihood testsofindependence (G-test;SokalandRohlf,1981)demonstrated thattheconstruction oftheplant'soffshoreintakeanddischarge structures significantly reducednestingattheplantsiteduringconstruction years-1975,1981,1982,1983(ABI,1987).However,nestingattheplantconsistently returnedtolevelssimilartoorgreaterthanthoseatacontrolsiteinyearsfollowing construction.

During1991whenoffshoreconstruction wasrestricted almostentirelytodaylighthours,nestsweremoreabundantattheplantsitethanatthecontrolsite.Datacollected through1998haveshownthatpowerplantoperation exclusive ofnighttime intake/discharge construction hashadnoapparenteffectonnesting.3.3.1.3Lon-TermTrendsinLoerheadTurtleNestinVariousmethodswereusedduringsurveyspriorto1981toestimatethetotalnumberofloggerhead nestsonHutchinson Islandbasedonthenumberofnestsfoundinthenine1.25lan-longsurveyareas(ABI,1980a).Eachofthesemethodswassubsequently foundtoconsistently overestimate islandtotals(ABI,1987).Sincewhole-island surveysbeganin1981,ithasbeenpossibletodetermine theactualproportion oftotalnestsdeposited inthenineareas.Thishasallowedextrapolation fromtheninesurveyareastotheentireislandforyearspriorto1981.From1981through1993thetotalnumberofnestsinthenineareasvariedfrom32.5to35.6percentofthetotalnumberofnestsontheisland.Thisisslightlyhigherthanthe31.3percent,whichwouldbeexpected, basedstrictlyontheproportion oflinearcoastline comprised bythenineareas.Usingthethirteen-year meanof33.81percent,estimates ofthetotalnumberofnestsonHutchinson Islandcanbecalculated bymultiplying thenumberofnestsinthenineareasby2.958.Thistechnique, whenappliedtotheninesurveyareasduringthethirteenyearsinwhichtheentireislandwassurveyed, producedwhole-island estimates within5.3percentoftheactualnumberofnestscounted.Becausetheproportion ofnestsrecordedintheninesurveyareasremainedrelatively constantoverthelastthirteenyears,thisextrapolation procedure providesafairlyaccurateestimateoftotalloggerhead nestingforyearspriorto1981,andisusedtogeneratedatapointsfor1971through1979inFigure6.Itisclearthatloggerhead-nesting activityonHutchinson Islandfluctuates considerably fromyeartoyear(Figure6).Annualvariations innestdensities alsoarecommonatotherrookeries, andmayresultfromnon-annual reproductive behavior.

Despitehighvariability, datacollected through1998suggestanoverallincreaseinnestingonHutchinson Islandsincesurveysbeganin1971.Totalnestingactivitywasgreatestduring1995when8184loggerhead nestswererecorded.

Norelationships betweentotalnestingactivityandpowerplantoperation orintake/discharge construction wereindicated byyear-to-year variations intotalnestingonHutchinson Island.3.3.1.4SeasonalPatternsofLoerheadTurtleNestinTheloggerhead turtlenestingseasonusuallybeginsbetweenmid-April andearlyMay,attainsamaximumduringJuneorJuly,andendsbymid-September (ABI,1987).Nestingactivityduring1998followedthissamepattern.Co'olwaterintrusions frequently occuroverthecontinental shelfofsoutheast Florida duringthesummer(Smith,1982).Theseintrusions mayhavebeenresponsible forthetemporary declinesinloggerhead turtlenestingactivitypreviously observedonHutchinson Island(ABI,1994).Thoughnaturalfluctuations intemperature havebeenshowntoaffecttemporalnestingpatternsonHutchinson Island,therehasbeennoindication thatpowerplantoperation hasaffectedthesetemporalpatterns(ABI,1988).3.3.1.5Predation onLoerheadTurtleNestsSincenestsurveysbeganin1971,raccoonpredation hasbeenamajorcauseofturtlenestdestruction onHutchinson Island.Researchers atotherlocations havereportedraccoonpredation levelsashighas70tonearly100percent(Hopkinsetal.,1979).Raccoonpredation ofloggerhead turtlenestsonHutchinson Islandhasnotapproached thislevelduringanystudyyear,thoughlevelsforindividual 1.25km-longareashavebeenashighas80percent.Overallpredation ratesforsurveyyears1971through1977werebetween21and44percent,withahighof44percentrecordedin1973.Apronounced decreaseinraccoonpredation occurredafter1977andoverallpredation ratesforthenineareashavenotexceeded10percentsince1979,Adeclineinpredation ratesonHutchinson Islandmaybeattributable totrappingprograms, construction activities, habitatloss,anddisease.During1998,raccoonpredation levelswereextremely low,withonlyoneloggerhead nestinareasA-Sdepredated byraccoons(Figure7).Inpreviousyears(ABI,1994),predation ofturtlenestswasprimarily restricted tothemoreundeveloped portionsoftheisland.Ghostcrabshavebeenreportedbynumerousresearchers asimportant predators ofseaturtlenests(Hopkinsetal,1979;Stancyk,1982).ThoughturtlenestsonHutchinson Islandprobablyhavebeendepredated byghostcrabssincenestingsurveysbeganin1971,quantification ofghostcrabpredation didnotbeginuntil1983.Overallpredation ratesbyghostcrabshavevariedfrom0.1to2.1percentfrom1983-1998.During1998,threeloggerhead nestinareasA-Sweredepredated byghostcrabs(Figure7).Nestsdestroyed byacombination ofraccoonandghostcrabpredation havebeenincludedasraccoonpredations inpreviousdiscussions.

Whenthesecombination predations areincludedascrabpredations, theoverallpredation ratesbyghostcrabsrangefrom0.1to4.7percent.During1998,nosuchcombination predations wererecorded.

3.3.1.61998GreenandLeatherback NestinSummaIn1998,258greenturtleand77leatherback turtlenestswererecordedinthe36one-kmsegmentscomprising Hutchinson Island.Thegreenturtletotalrepresents anewrecordforHutchinson Islandgreenturtlenestingandasubstantial increasefromlastyear'stotals,1998wasalsoarecordyearforleatherback turtlenestingonHutchinson Island(Figures8and9).Althoughstrongyeartoyearfluctuations arecommon,thegeneraltrendsince1971mayreflectanincreaseinthenumbersofnestingfemalesintheHutchinson Islandarea.

3.3.1.7TrendsinGreenandLeatherback TurtleNestinGreenandleatherback turtlesnestonHutchinson Island,butinfewernumbersthanloggerhead turtles.Priorto1981,bothsurvey(nine1.25km-longsections) andinter-survey areasweremonitored forthepresenceofgreenandleatherback nests.Thirty-one kilometers ofbeachfromArea1southtotheSt.LucieInletwereincludedinthateffort.Duringwhole-island surveysfrom1981through1993,only2.6percent(7)oftheleatherback nests(n=266)andonly1.4percent(12)ofthegreenturtlenests(n=831)wererecordedonthefivekilometers ofbeachnorthofArea1.Therefore, previouscountsofgreenandleatherback nestswithinthe31kilometers surveyedprobablywerenotappreciably different fromtotaldensities fortheentireisland.Basedonthisassumption, greenandleatherback nestdensities maybecomparedamongallsurveyyears,except1980,whenlessthan15kilometers ofbeachweresurveyed.

Sincesurveysbeganin1971,thenumberofnestsobservedontheislandrangedfrom5to258forgreenturtlesandfrom1to77forleatherbacks (Figures8and9).Temporalnestingpatternsforthesespeciesdifferfromthepatternforloggerhead turtles.Greenturtlestypically nestonHutchinson Islandfrommid-JunethroughthefirstorsecondweekofSeptember.

Leatherback turtlesusuallybeginnestinginMarchorAprilandcontinuetonestthroughearlytomid-July.

Considerable fluctuations ingreenturtlenestingontheislandhaveoccurredamongsurveyyears(Figure8).Thisisnotunusualsincetherearedrasticyear-to-year fluctuations inthenumbersofgreenturtlesnestingatotherbreedinggrounds(Carretal.,1982).Despitethesefluctuations, datacollected through1998suggestanoverallincreaseinnestingsince1971andmayreflectanincreaseinthenumberofnestingfemalesintheHutchinson Islandarea.During1998,greenturtlesnestedmostfrequently alongthesouthernhalfoftheisland.Thisisconsistent withresultsofprevioussurveys.Leatherback turtlenestdensities haveremainedlowonHutchinson Island,however,increased nestingduringrecentyears(Figure9)mayreflectanoverallincreaseinthenumberofnestingfemalesintheHutchinson Islandarea.

3.3.2INTAKECANALMONITORING Entrainment ofseaturtlesattheSt.LuciePlanthasbeenattributed tothepresumedphysicalattractiveness oftheoffshorestructures housingtheintakepipesratherthantoplantoperating characteristics (ABI,1980band1986).Thevelocitycaps,whicharesupported abovetheopeningstoeachintakepipe,eliminate verticalwaterentrainment andsubstantially reducecurrentvelocities nearthestructures byspreading horizontal drawoverawiderarea.Evenwhenbothunitsareoperating atfullcapacity, turtlesmustactivelyswimintothemouthofoneofthepipesbeforetheyencounter currentvelocities sufficiently strongtoeffectentrainment.

Consequently, aturtle'sentrapment relatesprimarily totheprobability thatitwilldetectandsubsequently enteroneoftheintakestructures.

3.3.2.11998CanalCatureSummaIn1998,666seaturtleswerecapturedintheintakecanaloftheSt.LuciePlant.Capturesincluded393loggerheads, 268greenturtles,1leatherback, 2hawksbill, and2Kemp'sridleyturtles(Table1).3.3.2.2RelativeAbundance andTemoralDistribution Sinceintakecanalmonitoring beganinMay1976,3578loggerhead (including 222recaptures),

2432green(including 478recaptures),

21leatherback, 33Kemp'sridleys,and21hawksbill capturehavetakenplaceattheSt.LuciePlant.Annualcatchesforallspeciescombinedrangedfromalowof33in1976(partialyearofplantoperation andmonitoring) to933in1995.Exceptfor1993through1997,whenthegreenturtlewasthemostabundantspeciesinthecanal,loggerheads have'dominated annualcaptures.

Since1977,thefirstfullyearofplantoperation, thenumberofloggerheads capturedeachyearrangedfrom62in1981to393in1998(Figure10).Numbershaveexhibited considerable year-to-year fluctuations withnopersistent trendsevident,althoughrecentyear'sdataaresuggestive ofapossibleincreasing trend.Thenumberofgreenturtlescapturedeachyearsince1977haverangedfrom3in1979toarecordhighof673in1995(Figure10).Increasing numbersofcapturesoverrecentyearsmayreflectanincreaseinthenumberofturtlesinhabiting thenearshore coastalareaneartheplantormaysimplyrepresent statistical variation.

Greenturtlecapturesweredownsharplyin1997,butshowedamodestreboundin1998.Additional yearsofcapturedatawillberequiredbeforeanylong-term trendscanbeestablished.

During1998,themonthlycatchofloggerheads rangedfrom10(November) to60(March),withamonthlymeanof32.7(Table2).Overtheentiiehistoryofthecaptureprogram,monthlycatcheshaverangedfrom0to87,withthegreatestnumberofcapturesoccurring duringJuly1996.During1998,themonthlycatchofgreenturtlesrangedfrom7(July)to58(February),

withamonthlymeanof23.3(Table3).TheMarch1996catchof147greenturtlesisthelargestnumberofcapturesforthisspeciesforanymonthonrecord.Seasonalabundance patternsof10 greenturtleshavetypically beenmuchmorepronounced thanforloggerheads, withover50percentofallcapturesoccurring betweenJanuaryandMarch.In1995through1998,however,nosuchseasonalpatternwasevident,withcapturesdistributed moreorlessevenlythroughout theyear.Catchesofleatherbacks, hawksbills, andKemp'sridleyshavebeeninfrequent andscattered throughout theyears.Eachspecieshasshownratherpronounced seasonaloccurrences; over60percentofallleatherbacks werecapturedinMarchandApril,over60percentofthehawksbills werecapturedbetweenJulyandSeptember, andalmost90percentoftheKemp'sridleyswerecaughtbetweenDecemberandApril.3.3.2.3Size-Class Distributions Thesize-class distribution forloggerheads removedfromtheintakecanalin1998ispresented inFigure11.Thesizeclassdistribution forgreenturtlesremovedfromtheintakecanalin1998arepresented inFigure12.ABI(1994)presentssize-class dataforturtlesremovedfromtheintakecanalfrom1976-1993.

Theleatherback capturedin1998wasanadult,withastraight-linecarapacelength(SLCL)ofover121cm(Hirth,1980).Bothhawksbills capturedin1998wereadults(SLCL>63cm)(Witzell, 1983).BothKemp'sridleyscapturedin1998werejuveniles SLCL(60cm)

(Hirth,1980).3.3.2.4SexRatiosOfthe390loggerheads capturedin1998forwhichstraightlinecarapacelengthsareavailable, 276werejuveniles withastraightlinecarapacelength(SLCL)lessthanorequalto70cm,81wereadults(SLCL>85cm)and33weretransitional (SLCL71-85cm)(Hirth,1980).Thelattergroupprobablyincludesbothmatureandimmatureindividuals.

Ofthe81individuals classified asadultsforwhomsexwasrecorded, 76werefemalesandfiveweremales,withfemalespredominating byaratioof15:1.Ofthe267greenturtlescapturedin1998forwhichstraightlinecarapacelengthsareavailable, 263werejuveniles orsub-adults (SLCL(83cm)(Whitherington andEhrhart,1989).Ofthe4adultgreenturtlescapturedin1998,2weremalesand2werefemales.ABI(1994)discusses sexratiodataforpreviousyears.3.3.2.5CatureEfficiencies Nettingmethodologies havebeenundercontinual reviewandrefinement asnetmaterials, configurations, andplacement bevariedinanefforttominimizeseaturtleentrapment times.Additionally, alternative capturetechniques havebeenevaluated, andpotential deterrent systemstestedinthelaboratory.

Currentcaptureprocedures haveproventoprovideasafe,efficient, andcost-effective programforremovingentrapped turtlesfromtheintakecanal.Formaldailyinspections oftheintakecanalareconducted everydaythatcapturenetsaredeployed, andthenumber,locationandrelativesizeofentrapped turtlesarerecordedonfieldobservation forms.Betterutilization ofcurrentsandeddies,adjustments totethering lines,multi-11 netdeployments andincreased effortstohandcaptureturtleshavecontributed toreducedentrapment timesduringrecentyears.Entrapment timesmaybeextendedforturtlesswimmingpasttheAlAbarriernet(ABI,1987).BecausecaptureeffortswestoftheA1Abridgeweregenerally lesseffective thanthoseneartheintakeheadwalls, mostturtlesbreaching thebarriernetwerenotcaughtuntiltheyenteredtheintakewellsofUnits1and2.Becauseoftheirrelatively smallsizes,virtually alltheturtlesreachingtheintakewellsaregreenturtles.During1998,5ofthe268greenturtlecaptures(1.8percent)occurredattheintakewells.Thesubstantial decreaseinthepercentage ofcapturesattheplantintakewellscomparedtothe1995figureof14.5percentisattributed totheeffectiveness ofthenewsmallmeshbarriernetinstalled eastofAIAinJanuary1996.During1998,99.1percentofallturtlesentrapped inthecanalwerecapturedeastoftheA1ABridge,547bytanglenetsand119byhandordipnetcapture.Theeffective confinement ofturtleseastofA1Ahasbeenamajorcontributor tothehighcaptureefficiency achievedduringrecentyears.Theinstallation ofanimprovedbarriernetcompleted inJanuary1996hasfurtherincreased captureefficiency bymoreeffectively confining turtlesofallsizestoasmallerareaeasttotheA1Abarriernet.3.3.2.6BarrierNetMaintenance Barriernetmaintenance iscriticalinreducingtheopportunity formortalities intheplantintakewellareaandinreducingresidence timesforturtlesintheintakecanalsystem.Dailyinspections areperformed fromasmallboattoremovefloatingdebrisandtorepairholesnearoratthewatersurface.Whenunderwater visibility conditions permit,aweeklyunderwater inspection isconducted.

Aformalinspection isconducted monthly,including holerepair,debrisremoval,andairliftdredgingofaccumulated siltifneeded.Maintenance conducted in1998includedtherepairofanyholesinthemeshdiscovered duringthedaily,weeklyandmonthlyinspections andextensive debrisremovalandairliftdredgingofaccumulated sedimentconducted inNovember.

InSeptember, October,andNovember1998,largeinfluxesofjeHyfishintotheintakecanalrequiredtheprimarybarriernettobeloweredperiodically, sometimes fordaysatatime,topreventthenetfromfailingundertheweightofaccumulated jellyfish.

Theloweringmechanism functioned asdesignedandnodamagewassustained.

3.3.2.7RelativeCondition TurtlescapturedaliveintheintakecanaloftheSt.LuciePlantwereassignedarelativecondition basedonweight,activity, parasiteinfestation, barnaclecoverage, wounds,injuriesandanyotherabnormalities whichmighthaveaffectedoverallvitality.

During1998,95.2%percent(373)ofallloggerheads foundinthecanalwerealiveandingoodcondition.

Only4.8percent(19)loggerhead capturesinvolvedindividuals infairorpoorcondition, andonewasdead.Ofthe268greenturtlesremovedfromtheintakecanalduring1998,254(94.8percent)wereingood'condition, 14(5.2percent)wereinfairorpoorcondition, andnoneweredead.The2hawksbills, 2Kemp'sridleys,andtheleatherback capturedin1998wereallingoodcondition.

12 Relativecondition ratingscanbeinfluenced byanumberoffactors,somerelatedandothersunrelated toentrainment and/orentrapment intheintakecanal.Aratingofgoodindicates thatturtleshavenotbeennegatively impactedbytheirentrapment inthecanal,atleastasevidenced byphysicalappearance.

Althoughratingsoffairorpoorimplyreducedvitality, theextenttowhichentrainment andentrapment isresponsible isoftenindeterminable.

Insomeinstances, conditions responsible forlowerratings,suchasboatcollision orfisheries gearentanglement injuriesobviously weresustained priortoentrainment.

During1998,71ofthe666turtlescaptured(10.7percent)hadnotableinjuriessuchasmissingappendages, brokenormissingpiecesofcarapace, ordeeplacerations.

Manyofthesewereold,well-healed wounds,anddidnotrequireveterinary attention.

Ofthe665liveremovalsduring1998,652werereleasedintotheoceanthedayofcapture.Nineturtles(allloggerheads) inobviousillhealthorsuffering seriousinjuriesweretransported toSeaWorldofFloridaortheMarinelife CenterofJunoBeachfortreatment andrehabilitation.

Twohadseriouscarapacedamage,presumably fromaboatcollision, onehadingestedmonofilament fishingline,andsixwereweak,lethargic, andemaciated whencaptured.

Fifteengreenturtleswithfibropapilloma tumorswereremovedfromthecanalin1998.Threeturtleswithextensive tumorsweretransferred totheFloridaDEPfortransportation toarehabilitation facility.

Twelveturtleswithminortumorsweretaggedandreleased.

Onegreenturtlewasheldovernight forinstallation ofasatellite-tracking transmitter andwaslaterreleased.

3.3.2.8Mortalities Seaturtlemortalities havebeencloselymonitored throughout thelifeofthecanalcaptureprograminanattempttoassignprobablecausesandtakeappropriate remedialactiontominimizefutureoccurrences.

Previousanalysesofcapturedataidentified drowninginnets(A1Abarriernet,UIDSbarrier,and.tangle nets),drowningintheintakepipesduringperiodsofreducedintakeflow,injuriessustained fromdredgingoperations, andinjuriessustained fromthemechanical rakesusedintheintakewellsasprobablemortality factors(ABI,1987)(FPL,1995).Althoughdifficult toquantify, theentrapment andsubsequent demiseofinjuredorsickturtleshasprobablyaccounted foraportionofobservedmortalities.

Overtheentiremonitoring programhistory,135(3.8percent)ofthe3578loggerheads and52(2.1percent)ofthe2432greenturtlesentrapped inthecanalwerefounddead.Mortalities spannedtherangeofsizeclassesforloggerheads (SLCL=47.5-103cm),whileallgreenturtlemortalities involvedjuveniles lessthan42cminlength.ThefourKemp'sridleymortalities documented attheplantduring1987and1988weretheonlydeathsforthisspeciestodate;nodeadleatherback orhawksbill turtleshavebeenrecovered attheSt.LuciePlant.Modifications tocaptureprocedures, improvements tobarriernets,andvirtualelimination oflowflowconditions withinthecanalhaveresultedinasubstantial reduction inseaturtlemortalities overthelifeofthecanalcaptureprogram.Mortality rate,expressed asthepercentage oftotalcapturesinvolving deadanimals,declinedfrom7.8percentduringtheperiod1976-1984 to2.1percentsince1984,and1.0%since1990(Table1).13 In1998,oneturtle(aloggerhead) wasremoveddeadfromtheintakecanal,foranoverallmortality rateof0.15percent.

TheturtlewasfoundfloatingupagainsttheA1Abarriernetduringaperiodwhentheprimarybarriernetwasloweredduetoajellyfish influx.Theturtlewasmoderately decomposed, andnocauseofdeathcouldbedetermined.

Inresponsetothe1995mortalities andthedramaticincreaseinintakecanalcapturesin1995,consultation wasinitiated withFPL,NRC,andtheNMFSunderSection7oftheEndangered SpeciesAct.Asaresultofthatconsultation, FPLhasdesignedandconstructed animproved, smallermeshbarriernetlocatedbetweentheA1Abarriernetandtheintakecanalheadwalls (Figure2).Construction ofthenetwascompleted inJanuary1996.ThisbarriernetpreventsturtlesfromreachingtheintakewellsorUIDSbarrierandincreases captureefficiency byconfining turtlestoasmallerareaoftheintakecanal.3.3.2.9RecatureIncidents SincetheSt.LuciePlantcaptureprogrambegan,mostturtlesremovedfromtheintakecanalhavebeentaggedandreleasedintotheoceanatvariouslocations alongHutchinson Island.Consequently, individual turtlescanbeidentified aslongastheyretaintheirtags.OverthehistoryoftheprogramattheSt.LuciePlant,700recaptures (222loggerheads and478greenturtles)haveoccurred, andanumberofturtleshavebeenrecaptured morethanonce,Therecapture rateforgreenturtlesin1998was37percentandtherecapture rateforloggerheads wasonly5.3percent.Thelargenumberofgreenturtlerecaptures probablyreflectsthesaturation oflocalgreenturtlepopulations withturtlestaggedattheSt.LuciePlantandpossiblyindicates adifference insitefidelitybetweengreenturtlesandloggerheads.

Severalotherturtleswithtagscarshavealsobeenrecovered indicating thattheactualnumberofrecaptures maybehigher.3.3.3SUMMARYAgradientofincreasing loggerhead turtlenestdensities fromnorthtosouthalongthenorthernhalfofHutchinson Islandhasbeenshownduringmostsurveyyears.Thisgradientmayresultfromvariations inbeachtopography, offshoredepthcontours, distribution ofnearshore reefs,onshoreartificial

lighting, andhumanactivityonthebeachatnight.Lownestingactivityinthevicinityofthepowerplantduring1975andfrom1981through1983wasattributed tonighttime construction activities associated withinstallation ofpowerplantintakeanddischarge structures.

Nestingreturnedtonormalorabovenormallevelsfollowing bothperiodsofconstruction.

During1991,daytimeconstruction activities associated withvelocitycaprepairshadnoapparenteffectonnesting.Statistical analysesindicatethatpowerplantoperation, exclusive ofnighttime construction, hashadnosignificant effectonnestdensities neartheplant.In1998,7962loggerhead turtlenestswererecordedonHutchinson Island.Therehavebeenconsiderable year-to-year fluctuations inloggerhead nestingactivityonHutchinson Islandfrom1971through1998.Fluctuations arecommonatotherrookeries andmayresultfromnon-annual reproductive behavior.

Despitethesefluctuations, loggerhead-nesting activityhasremainedhighduringrecentyearsandmayreflectanoverallincreaseinthenumberofnestingfemalesintheHutchinson Islandarea.Norelationship betweentotalnestingontheislandandpowerplantoperation orintake/discharge construction wasindicated.

14

~,

TemporalnestingpatternsoftheHutchinson Islandpopulation maybeinfluenced bynatural,largescalefluctuations inwatertemperature, suchasthoseproducedbythecoolwaterintrusions thatfrequently occuroverthecontinental shelfofsoutheast Floridaduringthenestingseason.However,localized fluctuations inwatertemperature associated withpowerplantoperation havehadnoapparenteffectonnesting.Sincenestingsurveysbeganin1971,raccoonpredation hasbeenoneofthemajorcausesofturtlenestdestruction onHutchinson Island.From1971through1977,overallpredation ratesintheninesurveyareaswerebetween21and44percent.However,apronounced decreaseinraccoonpredation occurredafter1977,andoverallpredation ratesintheninesurveyareashavenotexceededtenpercentsince1979.Decreased predation byraccoonsprobablyreflectsadeclineintheraccoonpopulation.

Moreyearsofsurveydatawillberequiredtodetermine iftheextremely lowlevelofraccoonpredation in1996through1998isanisolatedoccurrence orpartofacontinuing trend.Ghostcrabpredation ontheturtlenestsmaybemoresignificant thanpreviously documented butremainsrelatively minorcomparedtoraccoonpredation.

During1998,258greenturtleand77leatherback turtlenestswererecordedonHutchinson Island,arecordhighforbothspecies.Nestingactivitybythesetwospecieshasexhibited considerable annualfluctuations, ashasbeenrecordedatotherrookeries, buthasremainedrelatively highduringrecentyears.Thismayreflectanoverallincreaseinthenumberofnestinggreenandleatherback turtlesintheHutchinson Islandarea.During1998,393loggerheads, 268greenturtles,2hawksbills, 2Kemp'sridleys,andoneleatherback wereremovedfromtheSt.LuciePlantintakecanal.Sincemonitoring beganinMay1976,3578loggerhead, 2432green,21leatherback, 21hawksbill and33Kemp'sridleyturtleshavebeencapturedandtagged.Overthelifeofthemonitoring program,annualcatchesforloggerhead turtleshaverangedfrom33in1976(partialyearofplantoperation andmonitoring) toahighof393in1998.Yearlycatchesofgreenturtleshaverangedfrom0in1976to673in1995.Differences inthenumberofturtlesentrapped duringdifferent yearsandmonthsareattributed primarily tonaturalvariation intheoccurrence ofturtlesinthevicinityoftheoffshoreintakestructures, ratherthantoplantoperation characteristics.

Size-class distributions ofloggerhead turtlesremovedeachyearfromthecanalhaveconsistently beendominated byjuveniles between50and70cminstraight-line carapacelength.Over75percentofallgreenturtlesentrapped inthecanalwerejuveniles 40cmorlessinlength.Forbothspecies,thelargestnumberofcapturesforallyearscombinedoccurredduringwinter,but,withtheexception of1995,andtolesserextent1996,theseseasonalpeaksweremuchmorepronounced forgreenturtles.Thesexratioofloggerheads caughtinthecanalcontinued tobebiasedtowardsfemales.During1998,about95percentofallloggerheads andgreenturtlesremovedfromthecanalwerecategorized byphysicalappearance asbeingingoodcondition.

About10percentoftheturtlesremovedfromtheintakecanalduring1998hadsubstantial

injuries, andthevastmajorityofthosewerewellhealedandapparently sustained priortoentrapment.

Onceinthecanal,turtlesconfinedeastofA1Ahadverybriefresidency times.Thus115 therelativecondition ofmostturtleswasnotaffectedbytheirentrapment.

During1998,onlyonemortality wasaxordedintheintakecanal.Programmodifications, including continual surveillance oftanglenetsduringperiodsofdeployment, improvements totheintegrity ofthebarriernetsystem,andgreaterefforttohandcaptureturtleshavecontributed toasubstantial declineinseaturtlemortalities duringrecentyears.Thedesignandconstruction ofanimprovedbarriernetcompleted inJanuary1996wasexpectedtoreducemortalities andentrapment timesforturtlesintheintakecanal.Datasincethenindicatethatthenewbarriernetconfiguration hasbeenhighlyeffective inexcluding turtlesfromtheplantintakewells,buthasnotbeenaseffective inreducingtheoverallmortality rateasanticipated, althoughthe1998mortality rateof0.15%,thelowestmortality rateintheprogram's history,wasanoutstanding achievement andahopefulsignforthefuture.16

4.0 LITERATURE

CITED~~~~~ABI(AppliedBiology,Inc.),1978.Ecological Monitoring AtTheFloridaPower&LightCompanySt.LuciePlant,AnnualReport1977.VolumesIandII.AB-101.PreparedbyAppliedBiology,Inc.forFloridaPower&LightCompany,Miami.1980a.FloridaPower&LightCompany,St.LuciePlantAnnualNon-Radiological Environmental Monitoring Report1979.VolumesIIandIII,Bioticmonitoring.

AB-244.PreparedbyAppliedBiology,Inc.forFloridaPower&LightCompany,Miami.1980b.TurtleEntrainment Deterrent Study.AB-290.PreparedbyAppliedBiology,Inc.ForFloridaPower&I.ightCompany,Miami.1986.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1985.AB-563~PreparedbyAppliedBiology,Inc.forFloridaPower&LightCompany,JunoBeach.1987.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1986.AB-579.PreparedbyAppliedBiologyInc.forFloridaPower&LightCompany,JunoBeach.1988.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1987.AB-595.PreparedbyAppliedBiologyInc.forFloridaPower&LightCompany,JunoBeach.1989.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1988.AB-596.PreparedbyAppliedBiology,Inc.forFloridaPower&LightCompany,JunoBeach.1994.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Monitoring Report.AB-631.PreparedbyAppliedBiology,Inc.,forFloridaPower&LightCompany,JunoBeach.Carr,A.,A.Meyan,J.Mortimer, K.BjorndalandT.Carr,1982.SurveysofSeaTurtlePopulations andHabitatsintheWesternAtlantic.

NOAATechnical Memorandum NMFS-SEFC-91:1-82.

Davis,G.E.,andM.C.Whiting,1977.Loggerhead SeaTurtleNestinginEverglades NationalPark,Florida,U.S.A.Herpetologica 33:18-28.

Assessment oftheImpactsoftheSt.LucieNuclearGenerating PlantonSeaTurtleSpeciesFoundintheInshoreWatersofFlorida.FloridaPower&LightCompany,JunoBeach,FL.FPL,1995.Hirth,H.F.,1980.SomeAspectsoftheNestingBehaviorandReproductive BiologyofSeaTurtles.AmericanZoologist 20:507-523.

17 Hopkins,S.R.,T.M.Murphy,Jr.,K.B.StansellandP.M.Wilkinson, 1979.BioticandAbioticFactorsAffecting NestMortality intheAtlanticLoggerhead Turtle.Proceeding AnnualConference ofSoutheastern FishAndWildlifeAgencies32:213-223.

QuantumResources Inc.,1995.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1994.PreparedbyQuantumResources Inc.forFloridaPower&LightCompany,JunoBeach,FL.1996.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1995.PreparedbyQuantumResources Inc.forFloridaPower&LightCompany,JunoBeach,FL.1997.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1996.PreparedbyQuantumResources Inc.forFloridaPower&LightCompany,JunoBeach,FL.1998.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1997.PreparedbyQuantumResources Inc.forFloridaPower&LightCompany,JunoBeach,FL.Smith,N.P.,1982.Upwelling inAtlanticShelfWatersofSouthFlorida.FloridaScientist 45(2):125-138.Sokal,R.R.andF.J.Rohlf,1981.Biometry.

ThePrinciples andPracticeofStatistics inBiological

Research, S.H.FreemanandCompany,SanFrancisco.

859pp.Stancyk,S.E.,1982.Non-Human Predators ofSeaTurtleandTheirControl.Pages139-152inBjorndal, K.A.,ed.BiologyandConservation ofSeaTurtles.Smithsonian Institution Press.Washington, DCWitherington, B.E,andL.M,Ehrhart,1989.StatusandReproductive Characteristics OfGreenTurtles(Chelonia

~mdasNestinginFlorida.Pages351-352inOgren,L.,F.Berry,K.Bjorndal, H.Kumpf,R.Mast,G.Medina,H.ReichartandR.Witham,editors.Proceeding oftheSecondWesternAtlanticTurtleSymposium.

Mayaguez, PuertoRico,12-16October1987.NOAATechnical Memorandum NMFS-SEFC-226.

WIIIWN.1983.839IIEIIHMDE*HEEET\~EIIimbricata (Linnaeus, 1766).FAOFisheries

Synopsis, 137:1-78.18 FLORIDAGULFOFMEXICO-N-OKEECHOSEE STLUCIEPLANT~o>r~Figure1.LocationofSt.LuciePlant20 HUTCHINSON ISLANDINDIANRIVERvr~CGIQMUOCREEK,WTAIIS~~WELLSOISCHAACiE PIPESlAOSBAISIIEAo'llj5I~0~IIA(CHEAOWALLSATLANTICOCEANNAIA5'~SIIBABBIOIBAWCEBNH0MAKESIBVCTUIIES INDIANRIVERFigure2.St.I.uciePlantCoolingWaterIntakeandDischarge System21

~+oFT.PIERCEINLETA8DFQGHQSTATEHWYA1AK)OClNFPLST.LUCIEPLANTaQTUSTLucIEwQXYzgCCDDEgaGGHHpLIMITOFCURRENTSURVEYST.LUCIEINLETDRAWINGNOTTOSCALEf04llWSM2$

F)~)Figure3.Designation andLocationofNine1.25-KmSegmentsandThirty-Six 1-KmSegmentsSurveyedforSeaTurtleNesting,Hutchinson Island,1971-1998.

22 1000%900%80.0%7PP%60.0%500%0540.0%300%200%100%0.0%ABCDEFGHIJKLMN0PQRSPowerPlantFigure4.NumberofLoggerhead TurtlesNestsandEmergences forAreasAThroughS,Hutchinson Island,AprilThroughSeptember 1998.23 12000nestsClemergences 1000V8000600R4002000ABCDEFGHIJKLAREAMN0PowerPlantQRSFigure5.Loggerhead TurtleNestingSuccess(Percentage ofEmergences Resulting inNests)forAreasAThroughS,Hutchinson Island,AprilThroughSeptember 1998.24

• Il/~

9000800070006000z5000040003000z2000100071727374757677787980818283848586878889909192939495969798Figure6.NumberofLoggerhead TurtleNests,Hutchinson Island1971Through1998.Valuesfor1971Through1979AreEstimates (SeeText);Valuesfor1981Through1998ArePromWholeIslandSurveys.25 8CRABSONLY8RACCOONSONLY4rn10NoPFABCDEFGHIJKLMN2PQRSAREAPowerPlantIFigure7.Percentage ofLoggerhead TurtleNestsPredatedbyRaccoonsand/orGhostCrabsinAreasAThroughS,Hutchinson Island,AprilThroughSeptember 1998.26 300250~F200z150100z5071727374757677787980818283848586878889909192939495969798Figure8.Number.ofGreenSeaTurtleNests,Hutchinson Island,1971Through1998.Valuesfor1971Through1979AreEstimates (SeeText).Valuesfor1981Through1998ArefromWholeIslandSurveys.27 908070l"60z500g4030z201071727374757677787980818283848586878889909192939495969798Figure9.NumberofLeatherback TurtleNests,Hutchinson Island,1971Through1998.Valuesfor1971Through1979AreEstimates (SeeText).Valuesfor1981Through1998ArefromWholeIslandSurveys.28 800700~LOGGERHEAD

~GREEN600g5000>4003002001007677787980818283848586878889909192939495969798Figure10.Numberof-Loggerhead andGreenTurtlesRemovedEachYearfromtheIntakeCanal,St.LuciePlant,1976Through1998.29 908070605040302010(4141-4546-5051-5556-6061-6566-7071-7576-8081-8586-9091-9596-100101-105106-110)110SIRAIGHI'TANDARD CARAPACELENGTH(cm)Figure11.SizeDistribution (SSCL)ofLoggerhead Turtles(N=391)RemovedfromtheIntakeCanal,St.LuciePlant,1998.30 706050g40030201088~~~8888808888IIIIIIIIIIIIII8840R88g8STRAIGHTSTANDARDCARAPACELENGTH(cm)Figure12.SizeDistribution (SSCL)ofGreenTurtles(N=267)RemovedfromtheIntakeCanal,St.LuciePlant,1998.31 GreenSpeciesLeatherback'-

Hamksbill Kemp'sRidleyTotal1976197719781979198019811982198319841985198619871988198919901991199219931994199519961997199833(4)80(5)138(19)172(13)116(5)62(5)101(16)119(4)148(3)157(4)195(27)175(11)134(6)111(4)112(1)107(1)123(2)147164254(1)349(3)188393(1)5(2)6(1)3(1)10(3)32(2)823(4)69(2)1422(1)3542(2)17(1)20(2)1261(2)179(1)193(4)673(15)549(4)191(5)26816(2)5(2)233(4)86(7)148(20)175(14)126(8)97(7)110(16)142(8)220(5)172(4)220(28)218(13)181(10)133(5)132(3)121(1)187(4)337(1)361(4)933(16)906(7)382(5)666(1)Total357S(135)AnnualMean*162.62432(52)110.51.0211.034(4)1.55420(191)275.1*Excludes1976artialearoflantoration.Table1.TotalNumberofCapturesand(NumberofDead)TurtlesRemovedfromtheIntakeCanal33

'".Number':,'of.':;."-,.-';.-'--.'---;-:-;-".:-'.'---:--';-:

-";-';-:--."::Percent:of.

-."",;-:,';,

"",-.';-.~:-'=-:-'-"'.,:,.;"'.~'>'."..".>;-.::

'-'-Sta'ndard'<',":.-':--'"

'-.-."--'-"--':.'-;-

Mont1i:-'.::Catuxes'-"'-',;.,".':.<','":,'"".All[Ca'iir'es'-',.-Minimuiii'=;;::Ahmimimi'=:.-.'."'-'Mea'n.'

'Deviation'.-.--"..'=::--.-;="':

'.':.';:".:.'-'1998';";

JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptember OctoberNovemberDecember42133535436430436440532419419312516211.9%9.4%10.0%10.3%S.6%10.3%11.4%9.1%5.5%5.4%3.5%4.6%65100,302100139346047404287431927151319.115.216.116.513.816.518.414.78.88.85.77.410.28.414.712.710.411.120.112.25.2633.94.1362860472926574317271013TotalMeanStd.Deviation 354508713.44.639332.816.3*Firstfullyearofplantoperation.

Anadditional 33loggerheads werecapturedduring1976.Table2.TotalNumberofLoggerhead TurtlesRemovedEachMonthfromIntakeCanal,St.LuciePlant,1977-1998.34 Month.'umber=of-:

.=,.Percent.of.'.:-,',-.-.-Standard;-'.Catures,-'-.'All-Catures-:Minimum "Maxim'um:

MeanDeviation

--1998JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptember OctoberNovemberDecember28428937021018013712515114819815019011.7%11.9%15.2%8.6%7.4%5.6%5.1%6.2%6.1%8.1%6.2%7.8%000000000000596414764915261647754426812.913.116.89.58.26.25.76.96.79.06.88.615.518.335.617.320.212.614.115.217.815.410.815.82558302035167231025109TotalMeanStd.Deviation 24321479.23.426822.314.4~Firstfullearoflantoration.Table3.TotalNumberofGreenTurtlesRemovedEachMonthfromtheIntakeCanal,St.LuciePlant,1977-1998.

ANNUALENVIRONMENTAL OPERATING REPORTPARTII

1.0INTRODUCTION

TheSt.LucieUnit2Environmental Protection Plan(EPP)requiresthesubmittal ofanannualreportforvariousactivities attheplantsiteincluding thereporting onseaturtlemonitoring programsandothermattersrelatedtoFederalandStateenvironmental permitsandcertifications.

2.0 SEATURTLEMONITORING

ANDASSOCIATED ACTIVITIES Surveillance andmaintenance ofthelightscreentomiiuinize seaturtledisorientation aszcquiredbySection4.2.4oftheEPPisongoing.Thevegetation lightscreenlocatedonthebeachdunebetweenthepowerplantandtheoceanisroutinely surveyedtodetermine itsoverallvitality.

Thevegetation lineissurveyedforanygapsoccurring frommortality, whichwouldresultinunacceptable lightlevelsonthebeach.Trees,vegetation, orshadeclothsarereplacedasnecessary tomaintaintheoverallintegrity ofthelightscreen.Plantparkinglotlightingisalsodesignedandmaintained tominimizelightlevelsonthebeach.3.0TAPROGGECONDENSER TUBECLEANINGSYSTEMOPERATION ATaproggecondenser tubecleaningsystem(CTCS)becameoperational onSt.LucieUnit2inJanuary1996andonUnit1inJuly1996.Thissystemutilizesspongeballs,approximately 24mmindiameter, tocleanthecondenser tubesthroughwhichseawaterflowstocoolsteamafteritspassthroughtheplant'sturbines.

Thissystemimprovesplantperformance whilereducingtheneedforchemicaltreatments suchandbiocidesorchlorinetocontrolbiofouling.

Normally, theSt.LucieCTCSutilizesabout1800spongeballs,whicharecontinually recirculated througheachoffour"waterboxes"oneachunit.Thesespongeballsareretainedinthesystembyaballstrainerlocatedontheoutletofeachwaterbox.Theballstrainers (meshsize5mm)areopenedroutinely todischarge debris,whichcandecreasefiowandobstructspongeballmovement.throughthesystem.Thespongeballsarecollected priortoopening,orbackflushing, theballstrainers.

Atthattime,thespongeballsareexaminedandreplacediftheyareworntothepointthattheycannolongereffectively cleanthecondenser tubes.Spongeballinventories andestimates ofspongeballlosstotheenvironment havebeenperformed sincesystemstart-uponbothunits.Numberofballstrainerbackflusheshasalsobeentracked.Inaddition, dailybeachsurveyshavebeenperformed onplantproperty(approximately 2.5miles)tonoteanyspongeballsthatmayhaveappearedasaresultoflossfromtheplant.Thissurveyareahasbeenextendedduringtheturtle-nesting seasontoalmost12miles.Theresultsoftheprogramfor1998arepresented inTable1.LargerspongeballlossesoccurredonUnit2fortheyear.Theselossesareprobablyrelatedtothefactthat1998represents theendoffuelcycleforthatunit.Estimated spongeballlossfrombothunitswas20.2ballsperdayfor1998.Fiftyspongeballswerefoundwholeintheenvironment neartheplant.Thisisanincrease36 overpreviousyears,butthenumberindicates thatfewballsactuallyreachtheenvironment whole.Figure1indicates thatestimated spongeballlossgenerally increased throughthemonthofAprilof1998,Averagedailyballlossin1998increased fromthe1996and1997totals(Figure2).Itisbelievedthatmuchofthelossesarecausedbyincreased growthinsidethewaterboxes.

Newcoatingsonthesesurfacesarebeingusedtotrytoeleviatethisproblem.ThesecoatingwereappliedtoUnit2inDecember1998.Ifthecoatingproveseffective itwillbeappliedtoUnit1inSeptember 1999.4.0OTHERROUTINEREPORTSThefollowing itemsforwhichreporting isrequiredarelistedbysectionnumberfromtheplant'sEnvironmental Protection Plan:5.4.1(a)EPPNONCOMPLIANCES ANDCORRECTIVE ACTIONSTAKENNononcompliance's underEPPSection5.4.1(a)weredetermined tohaveoccurredduring1998.5.4.1(b)CHANGESINSTATIONDESIGNOROPERATION TESTSANDEXPERIMENTS INACCORDANCE WITHEPPSUBSECTION 3.15.4.1(c)FPLletterL-98-180transmitted therequestformodification ofWastewater PermitApplication toFDEP.Themodification includestheuseofbiocideintheplantclosedcoolingwatersystemsandtheuseofdimethylamine andcarbohydrazide intheplantsteamgenerator blowdown.

Thisletterwastransmitted June26,1998.NONROUHNB REPORTSSUBMITI'ED TOTHENRCFORTHEYEAR1998INACCORDANCE WITHEPPSUBSECTION 5.4.22.Reportconcerning themortality LeastTernsattheplantNuclearTrainingCenterJuly6,1998andJuly17,1998.Deathsoccurredinthebuilding's drainagesystemduringheavyrainfall.

EventswerereportedtoNRCbyFPLletterL-98-196onJuly23,1998.Reportconcerning anincreaseofjellyfish andsubsequent effectofplantoperation onSeptember 9,1998;reportedtotheNRCbyFPLletterL-98-250onOctober1,1998.37 TABLE11998ST.LUCIEPLANTCONDENSER TUBECLEANINGSYSTEMSUlVBZARY

'MONTH'.;,-.STRAINER.BACKQLUSEES;,.';.;ESTIMATED'.;BALL'"XOSS

~',A:..j.':'."UNIT;:2'-.;+

',;,'BALLS'FOUND

.',;.,ONTHE.BEACH;"-',:.":"';:,

JanuaryFebruaryMarch10222226+26":'~2541698627613AprilMayJune0"252924241242+22QQQ852580JulyAugustSeptember October2925312327202313066114129586483228November24623229December2576759Total1972341853551050Duetopoorspongeballrecovery, strainers werenotback-flushed.

Unitwasdown-powered,waterboxes takenoutofserviceformanualremovalofgrowthandballs.Unit1systemshutdownduringrefueling, 1/1to1/19/98.Unit2systemshutdownduringrefueling, 11/6to12/12/98.

Netgainininventory.

38 504540Q35~~3025g20gis10JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDECMONTHFigure1.Estimated AverageDailySpongeBanLossbyMonthfromSt.LuciePlant(BothUnits)for1998.39 2520015g10199619971998Figure2.AverageDailySpongeBallLossfromtheSt.LuciePlant(BothUnits)SinceSystemStart-Up(January1996)40 FLOKfBAPOWERdkLIGHTCOMPANYST.LUCIEUNIT2AINMJALElVVIR()bMIKNYAL OPERATING.

REPORT1998FLORlDAPOWER&LIGHT.COMPANYJUNOBEACH,FLORIDAQUANTIUMRESOURCES, INC.PALMBEACHGARDENS,FLORIDA

F<2AZRONMENTAL OPERATING REPORTTABLEOFCONTENTSPARTI1.0Executive Summary1.1Introduction 1.2TurtleNestingSurvey1.3IntakeCanalMonitoring

2.0 Introduction

iv2.1Background 2.2AreaDescription 2.3PlantDescription 3.0Turtle3.1Introduction 3.2Materials andMethods3.2.1NestingSurvey3.2.2IntakeCanalMonitoring 3.3ResultsandDiscussion 3.3.1NestingSurvey3.3.1.11998Loggerhead NestingSummary3.3.1.2SpatialDistribution ofLoggerhead TurtleNests63.3.1.3Long-Term TrendsinLoggerhead TurtleNesting73.3.1.4SeasonalPatternsofLoggerhead TurtleNesting73.3.1.5Predation onLoggerhead TurtleNests3.3.1.61998GreenandLeatherback NestingSurvey3.3.1.7TrendsinGreenandLeatherback TurtleNesting9 3.3.2IntakeCanalMonitoring 3.3.2.11998CanalCaptureSummary10103.3.2.2RelativeAbundance andTemporalDistribution 103.3.2.3SizeClassDistributions 3.3.2.4SexRatios3.3.2.5CaptureEfficiencies 3.3.2.6BarrierNetMaintenance 3.3.2.7RelativeCondition 3.3.2.8Mortalities 3.3.2.9Recapture Incidents 3.3.3Summary4.0Literature Cited12121314175.0Figures6.0Tables1932PARTII1.0Introduction

2.0 SeaTurtleMonitoring

andAssociated Activities

3.0 TaproggeCondenser

TubeCleaningSystemOperation 4.0OtherRoutineReports5.0TableandFigures3636363738

1.0 EXECUTIVE

SUMMARY

1.1INTRODUCTION

TheSt.LuciePlantisanelectricgenerating stationonHutchinson IslandinSt.LucieCounty,Florida.Theplantconsistsoftwonuclear-fueled 850netMWeunits;Unit1wasplacedon-lineinMarch1976andUnit2inApril1983.Thisdocumenthasbeenpreparedtosatisfytherequirements contained inAppendixB,Environmental Protection Plan(EPP),toSt.LucieUnit2FacilityOperating LicenseNo.NPF-16.Thisreportprimarily discusses environmental protection activities relatedtoseaturtlesasrequiredbySubsection 4.2oftheEPP.Otherroutineannualreporting requirements areaddressed inVolume2.1.2TURTLENESTINGSURVEYSincemonitoring beganin1971,therehavebeenconsiderable year-to-year fluctuations inseaturtlenestingactivityonHutchinson Island.However,datacollected through1998haveshownnolong-term reductions innestingontheisland.Relatively highnestingduringrecentyearsmayactuallyreflectanincreaseinthenumberofnestingfemalesinthestudyarea.Onasmallerscale,powerplantoperation hashadnosignificant effectonnestingneartheplant.Lownestingactivityin1975andagainin1981-1983 inthevicinityoftheplantwasattributed tonighttime construction activities associated withinstallation ofplantintakeanddischarge structures.

Nestingreturnedtonormalorabovenormallevelsfollowing bothperiodsof~~~~~~~~~~~construction.

During1991,daytimeconstruction activities associated withvelocitycaprepairshadnoapparenteffectonnesting.Formalrequirements toconductnestingsurveysexpiredin1986,butthisprogramhasbeencontinued through1998withagreement fromfederalandstateagencies.

In1998,thecontinuation ofthenestingsurveyprogramwasmandatedaspartofthebiological opinionandincidental takestatement issuedbytheNationalMarineFisheries Service.1.3INTAKECANALMONITORING Sinceplantoperation beganin1976,6086seaturtles(including recaptures) representing fivedifferent specieshavebeenremovedfromtheintakecanal.Themajorityoftheturtlescaptured(59percent)wereloggerheads.

Differences inthenumbersofturtlesfoundduringdifferent monthsandyears,including dramaticincreases ingreenturtlecapturesinrecentyears,havebeenattributed primarily tonaturalvariation intheoccurrences ofturtlesinthevicinityoftheplant,ratherthantooperational influences oftheplantitself.Themajorityofturtlesremovedfromtheintakecanal(about97percent)werecapturedaliveandreleasedbackintotheocean.Ongoingevaluations andimprovements tothecanalcaptureprogramhavesubstantially reducedmortalities ofentrapped seaturtlesduringrecentyears.Turtlesconfinedbetweenthebarriernetandintakeheadwalls typically resideinthecanalforarelatively shortperiodpriortocapture,andmostareingoodtoexcellent condition whencaught.Animproveddesignbarriernetcompleted inJanuary1996isexpectedtofurtherreducetheresidence timesandpotential formortalities toseaturtlesintheintakecanalsystem.

2.0INTRODUCTION

2.1BACKGROUND Thisdocumenthasbeenpreparedtosatisfytherequirements contained inAppendixB,Environmental Protection Plan,toSt.LucieUnit2FacilityOperating LicenseNPF-16.St.LucieUnits1and2usetheAtlanticOceanasasourceofwaterforonce-through condenser cooling.Since1971,thepotential environmental effectsresulting fromtheintakeanddischarge ofthiswaterhavebeenthesubjectofFPLsponsored bioticstudiesatthesite.Jurisdiction forseaturtlestudiesiswiththeNRC,whichisconsidered tobetheleadfederalagencyrelativetoconsultation undertheEndangered SpeciesAct.Previousresultsdealingwithseaturtlestudiesarecontained infourteenannualenvironmental operating reportscoveringtheperiodfrom1983through1997.Thisreportdescribes the1998environmental protection activities relatedtoseaturtles,asrequiredbySubsection 4.2oftheSt.LucieUnit2Environmental Protection Plan.2.2AI&ADESCRIPTION TheSt,LuciePlantislocatedona457-hectare siteonHutchinson IslandonFlorida's EastCoast(Figures1and2).Theplantisapproximately midwaybetweentheFt.PierceandSt.LucieInlets.ItisboundedontheEastSidebytheAtlanticOceanandontheWestSidebytheIndianRiverLagoon.Hutchinson Islandisabarrierislandthatextends36kmbetweeninletsandattainsitsmaximumwidthof2kmattheplantsite.Elevations approach5matopdunesbordering thebeachanddecreasetosealevelinthemangroveswampsthatarecommononmuchofthewesternside.TheAtlanticshoreline ofHutchinson Islandiscomposedofsandandshellhashwithintermittent rockypromontories protruding throughthebeachfacealongthesouthernendoftheisland.Submerged coquinoid rockformations parallelmuchoftheislandofftheoceanbeaches.Theoceanbottomimmediately offshorefromtheplantsiteconsistsprimarily ofsandandshellsediments.

TheFloridaCurrent,whichflowsparalleltothecontinental shelfmargin,beginstodivergefromthecoastline atWestPalmBeach.AtHutchinson Island,thecurrentisapproximately 33kmoffshore.

Oceanicwaterassociated withthewesternboundaryofthecurrentperiodicaHy meandersovertheinnershelf,especially.

duringsummermonths.2.3PLANTDESCRIPIION TheSt.LuciePlantconsistsoftwo850netMWenuclear-fueled electricgenerating unitsthatusenearshoreoceanwatersfortheplant'sonce-through condenser coolingwatersystem.Waterfortheplantentersthroughthicesubmerged intakestructures locatedabout365moffshore(Figure2).Eachoftheintakestructures isequippedwithavelocitycaptominimizefishentraiiiment.

Fromtheintakestructures, thewaterpassesthroughsubmerged pipes(two3.7mandone4.9mindiameter) underthebeachanddunesthatleadtoa1,500meterlongintakecanal,whichtransports watertotheplant.Afterpassingthroughtheplant,theheatedwaterisdischarged intoa670meterlongcanalthatleadstotwoburieddischarge pipelines.

Thesepassunderneath thedunesandbeachandalongtheoceanfloortothesubmerged discharges, thefirstofwhichisapproximately 365moffshoreand730mnorthoftheintake.

3.1INTRODUCTION

Hutchinson Island,Florida,isanimportant rookeryfortheloggerhead turtle,Caxettacaretta,andalsosupportssomenestingofthegreenturtle,Chelonia~mdas,andtheleatherhack I,~D*h*l'.SdfH*MpHitwi.ThfdIgovernment hasclassified theloggerhead turtleasathreatened species.Thefederalgovernment endangered specieslistsincludetheleatherback turtleandtheFloridanestingpopulation ofthegreenturtle.IthasbeenanFPLgoalthattheSt.LuciePlantwouldnotadversely affecttheHutchinson Islandrookery.Becauseofthisconcern,FPLhassponsored monitoring ofmarineturtlenestingactivityontheislandsince1971.Daytimesurveystoquantifynesting,aswellasnighttime turtletaggingprograms, wereconducted inoddnumberedyearsfrom1971through1979.Duringdaytimenestingsurveys,nine1.25km-longsurveyareasweremonitored fivedaysperweek(Figure3).TheSt.LuciePlantbeganoperation in1976;therefore, thefirstttueesurveyyears(1971,1973,and1975)werepre-operational.

Thoughthepowerplantwasnotoperating during1975,St.LuciePlantUnit1oceanintakeanddischarge structures wereinstalled duringthatyear.Installation ofthesestructures includednighttime construction activities conducted offshorefromandperpendicular tothebeach.Construction hadbeencompleted andtheplantwasinfulloperation duringthe1977and1979surveys.Amodifieddaytimenestingsurveywasconducted in1980duringthepreliminary construction oftheoceandischarge structure forSt.LucieUnit2.Duringthisstudy,fourofthepreviously established 1.25km-longsurveyareasweremonitored.

Additionally, eggsfromturtlenestspotentially endangered byconstruction activities wererelocated.

Everyyearfrom1981through1998,36one-km-long surveyareascomprising theentireislandweremonitored sevendaysaweekduringthenestingseason(Figure3).Beginning in1994,thesouthernhalfoftheislandhasbeensurveyedbyEcological Associates ofJensenBeach,Florida,andtheirdataisincludedinthisreport;TheSt.LucieUnit2discharge structure wasinstalled duringthe1981nestingseason.Offshoreandbeachconstruction oftheUnit2intakestructure proceeded throughout the1982nestingseasonandwascompleted neartheendthe1983'esting season.Construction activities associated withinstallation ofbothstructures weresimilartothoseconducted whenUnit1intakeanddischarge structures wereinstalled.

Eggsfxomturtlenestspotentially threatened byconstruction activities wererelocated.

During1991,anothermajoroffshoreconstruction projectwasundertaken toreplacedamagedvelocitycapsonthethreeintakestructures.

Alargeelevatedplatform, fromwhichrepairactivities wereconducted, waserectedaroundthethreestructures.

Construction occurredthroughout thenestingseason.However,incontrasttopreviousoffshoreprojects, workwasrestricted almostentirelytodaylighthours,nighttime lightingoftheworkareawasminimal,andnoequipment ormaterials wereusedonthebeach.Aseaturtleprotection planimplemented insupportoftheprojectincludedcagingofnestsalonga1,500metersectionofbeachwestoftheplatformandreleaseofhatchlings tounaffected areastothenorthandsouth.Thisplanwas intendedtomitigateanynegativeeffectspotentially resulting fromreIuiredsafetyandnavigational

~~~~~~~~~~~~~~~~lightingonandneartheplatform.

Requirement 4.2.1oftheSt.LucieUnit2AppendixBEnvironmental Protection Planwascompletewithsubmission ofthe1986nestingsurveydata(ABI,1987).Thenestingsurveywascontinued voluntarily through1998withagreement fromfederalandstateagencies.

Resultsarepresented inthisreportanddiscussed inrelationtopreviousfindings.

Inadditiontomonitoring seaturtlenestingactivities andrelocating nestsawayfromplantconstruction areas,removalofturtlesfromtheintakecanalhasbeenanintegralpartoftheSt.LuciePlantenvironmental monitoring program.Turtlesenteringtheoceanintakestructures areentrained withcoolingwaterandrapidlytransported throughtheintakepipesintoanenclosedcanalsystemwheretheymustbemanuallycapturedandreturnedtotheocean.Sincetheplantbecameoperational in1976,turtlesentrapped intheintakecanalhavebeensystematically

captured, measured, weighed,tagged,andreleased.

Previouspublications andtechnical reportshavepresented findingsofthenestingsurveys,nestrelocation activities andcanalcaptureprogram(ABI,1994)(Quantum, 1995,1996,1997,1998).Resultsofstudiestoassesstheeffectsofthermaldischarges onhatchling swimniing speedhavealsobeenreported(ABI,1978).InJuly1994,responsibility forseaturtleresearchandconservation activities wastransferred fromEcological Associates, Inc.(formerly AppliedBiology,Inc.)toQuantumResources, Inc.Methodologies employedinboththenestingsurveys~~~~~~andcanalcaptureoperations remainedessentially unchanged sothatdatacollected in1994throughthepresentaredirectlycomparable topreviousyear'sdata.Thepurposeofthisreportisto:1)present1998seaturtlenestingsurveydataandsummarize observedspatialandtemporalnestingpatternssince1971,2)documentandsummarize predation onturtlenestssince1971,and3)present1998canalcapturedataandsummarize comparable datacollected since1976.3.2MATEIUALS ANDMETHODS3.2.1~N'31Methodologies usedduringpreviousturtlenestingsurveysonHutchinson Islandweredescribed inearlierreports(ABI1994).Methodsusedduringthe1998surveyweredesignedtoallowcomparisons withthesepreviousstudies.In1998,onlyareasA-SweresurveyedbyQuantumResources biologists (Figure3).DatasuppliedbyEcological Associates, Inc.areusedtoprovidewholeislandnestingtotalsinFigures6,8,and9.FromMarch24,1998throughApril14,1998,severalpreliminary nestsurveyswereconducted alongHutchinson IslandinareasA-S.NonestingwasrecordedinareasA-Spriortothebeginning offormalnestingsurveysonApril15,1998.FromApril15,1998throughSeptember 8,1998,nestsurveyswereconducted onadailybasis.Thelastnestrecordedinarea~~~~A-SwasonSeptember 7,1998.Biologists usedsmalloff-roadmotorcycles tosurveytheislandeachmorning.Newnests,non-nesting emergences (falsecrawls),andnestsdestroyed by predators wererecordedforeachofthe1-km-long surveyareasA-S(Figure3).The1.25-km-longsurveyareasthatwereestablished inearlierstudiesalsoweremonitored socomparisons couldbemadewithpreviousstudies.Datacollected frombeachnestingsurveyswerereportedtotheFloridaDepartment ofEnvironmental Protection (FDEP)aspartoftheFDEPIndexNestingBeachSurvey.Inacooperative effort,datafromstrandedturtlesfoundduringbeachsurveyswereroutinely providedtotheFloridaDepartment ofEnvironmental Protection andtheNationalMarineFisheries ServicePG&S)throughtheSeaTurtleStranding andSalvageNetwork:3.2.2IntakeCanalMonitorin Mostturtlesentrapped intheSt.LuciePlantintakecanalwereremovedbymeansoflarge-meshtanglenetsfishedneartheintakecanalheadwalls attheextremeeasternendoftheintakecanal(Figure2).Netsusedduring1998werefrom30to40minlength,3to4mdeepandcomposedof40cmsketchmeshmultifilament nylon.Largefloatswereattachedtothesurface,andunweighted linesusedalongthebottom.Turtlesentangled inthenetsgenerally remainedatthewater'ssurfaceuntilremoved.Sinceitsinception in1976,thecanalcaptureprogramhasbeenundercontinual reviewandrefinement inanattempttominimizebothentrapment timeandinjuries/mortalities toentrapped seaturtles.PriortoApril1990,turtlenetswereusuallydeployedonMondaymorningandretrieved onFridayafternoon.

Duringperiodsofdeployment, thenetswereinspected forcapturesatleasttwiceeachday(mornings andafternoons).

Additionally, St.LuciePlantpersonnel checkedthenetsperiodically, andbiologists werenotifiedimmediately whenacapturewasobserved.

Seaturtle'specialists, thatretrievecapturedturtlesfromtheplantintakecanalsystem,wereoncall24hoursaday.Beginning April1990,afterconsultation withNMFS,netdeployment wasscaledbacktodaylighthoursonly.Concurrently, surveillance oftheintakecanalwasincreased andbiologists remainedonsiteforthedurationofeachday'snettingactivities.

Thismeasuredecreased responsetimeforremovalofentangled turtlesfromnetsandprovidedanopportunity toimprovedailyassessments ofturtlelevelswithinthecanal.Recordsofdailycanalobservations werecomparedwithcapturedatatoassesscaptureefficiencies.

In1978,abarriernetattheA1ABridgewasconstructed toconfineturtlestotheeasternmost sectionoftheintakecanal,wherecapturetechniques havebeenmosteffective.

Thisnetisconstructed oflargediameterpolypropylene ropeandhasameshsizeof20.3cmx20.3cm.Acableandseriesoflargefloatsareusedtokeepthetopofthenetabovethewater'ssurface,andthebottomisanchoredbyaseriesofconcreteblocks.Thenetisinclinedataslopeof1:1,withthebottompositioned upstreamofthesurfacecable.Thisreducesbowinginthecenterandminimizes theriskofaweakorinjuredturtlebeingpinnedunderwater bystrongcurrents.

Inthepast,theintegrity ofthebarriernetwasoccasionally compromised, andturtleswereabletomovewestofA1A.Theseturtleswerefurtherconstrained downstream byanunderwater intrusion detection system(UIDS)consisting, inpart,ofalargebarrierpositioned perpendicular tothenorth-south armofthecanal(Figure2).TheUIDSsecuritybarrierhasameshsizeof22.9cmx22.9cm.Priortocompletion oftheUIDSinDecember1986,turtlesunconfined bythe A1AbarriernetwereusuallyxemovedfromthecanalattheintakewellsofUnits1and2(Figure2).Theretheywereretrieved bymeansoflargemechanical rakesorspecially designednets.Following construction oftheUIDSbarrier,allbutthesmallestindividuals wereunabletoreachtheintakewells.Improvements madetotheA1Abarriernetduring1990haveeffectively confinedallturtleslargerthan-32.5-cm carapacelength(28.7-cmcarapacewidth)totheeasternendofthecanal.Inresponsetothelargenumbersofsmallturtlesencountered intheintakecanalinrecentyears,animproveddesign,smallmeshbarriernetwaserectedeastoftheA1Abarriernet.Construction wascompleteinJanuary1996.Thisimprovedbarriernetisdesignedtoconfineallturtleswithacarapacewidthgreaterthan18cmtotheextremeeasternportionoftheintakecanal.Formaldailyinspections oftheintakecanalweremadetodetermine thenumbers,locations, andspeciesofturtlespresent.Surfaceobservations wereaugmented withperiodicunderwater inspections, particularly inandaroundthebarriernets.Inadditiontotheuseoftanglenets,dipnetsandhandcapturesusingsnorkelandSCUBAwerealsoemployed.

Longhandleddipnets,employedfromsmallboats,thecanalbanksandheadwallstructures weremoderately effective incapturing turtleswithcarapacelengthsofabout30cmorless.Diverswereemployedtohandcaptureturtleswheneverunderwater visibility permits,andthistechnique hasprovenhighlyeffective inthecaptureofturtlesofallsizes,particularly lessactiveindividuals oftenfoundpartially buriedinthesedimentinthevicinityofthebarriernets.Handcaptureeffortshavehadasignificant impactinreducingentrapment timesforturtlesintheintakecanal.Regardless ofcapturemethod,allturtlesxemovedfromthecanalwereidentified tospecies,measured, weighed,taggedandexaminedforoverallcondition (wounds,abnormalities, parasites, etc.).Beginning inJuly1994,allturtlescapturedhavebeenphotographed dorsallyandventxally priortoxelease,andthephotographs retainedforfuturereference.

Healthyturtleswerereleasedintotheoceanthesamedayofcapture.Sickorinjuredturtlesweretreatedandoccasionally heldforobservation priortorelease.Whentreatment waswarranted, turtlesweretransported toanapprovedrehabilitation facility.

Resuscitation techniques wereusedifaturtlewasfoundthatappearedtohavediedrecently.

Beginning in1982,necropsies wereconducted ondeadturtlesfoundinfreshcondition.

'loridaPower&LightCompanyandQuantumResources, Inc.continued toassistotherseaturtleresearchers in1998.Sincetheprogrambegan,data,specimens and/orassistance havebeengiventotheFloridaDepartment ofEnvironmental Protection, NationalMarineFisheries Service,USFishandWildlifeService,USArmyCorpsofEngineers, Smithsonian Institution, SouthCarolinaWildlifeandMarineResources

Division, CenterforSeaTurtleResearch(University ofFlorida),

FloridaAtlanticUniversity, University ofCentralFlorida,TexasA&MUniversity, University ofRhodeIsland,University ofSouthCarolina, University ofIllinois, University ofGeorgia,VirginiaInstitute ofMarineScience,WesternAtlanticTurtleSymposium, SouthAtlanticFisheryManagement Council,FloridaMarineFisheries Commission, HarborandBranchOceanographic Institution andtheNationalResearchCouncil.

3.3RESULTSANDDISCUSSION 3.3.1N~33.3.1..11998LoerheadNestinSummIn1998,7962loggerhead turtlenestswererecordedinthe36one-kilometer segmentscomprising Hutchinson Island.Thisfigureisinaccordance withageneralincreaseinloggerhead turtlenestingonHutchinson Islandsincesurveysbeganin1971,althoughsignificant yeartoyearfluctuations areevident.loggerhead nestsandemergences forsurveyareasA-Sispresented inFigure4.3.3.1.2SatialDistribution ofLoerheadTurtleNestsFrom1981through1998,36one-km-long segmentscomprising theisland'scoastline havebeensurveyed.

Thedistribution ofnestsamongthese36surveyareashasshownanincreaseinnestingfromnorthtosouthalongthenorthernhalfoftheisland(ABI,1987,1994).Alongthesouthernhalfoftheislandtherehasbeeneithernogradientoragradientofdecreasing nestingfromnorthtosouth.Thoughbeachdynamicsmaysometimes affecttheselection ofnestingsitesbyloggerhead turtles,relationships betweenspatialnestingpatternsandspecificenvironmental conditions areoftendifficult toestablish becauseoftheinterxelationship ofthefactorsinvolved.

Notallventuresontothebeachbyafemaleturtleculminate insuccessful nests.These"falsecrawls"(non-nesting emergences) mayoccurformanyreasonsandarecommonlyencountered atotherrookeries.

DavisandWhiting(1977)suggested thatrelatively highpercentages offalsecrawlsmightreflectdisturbances orunsatisfactory nestingbeachcharacteristics.

Thexefore, certainfactorsmayaffectaturtle'spreference toemergeonabeach,whileotherfactorsmayaffectaturtle'stendencytonestafterithasemerged.Anindex,whichrelatesthenumberofneststothenumberoffalsecrawlsinanarea,isusefulinestimating thepost-emergence suitability of'abeachfornesting.Inthepresentstudythisindexistermed"nestingsuccess"andisdefinedasthepercentage oftotalemergences thatresultinnests.loggerhead nestingsuccessforareasA-Sin1998ispresented inFigure5.Historically, thepatternofloggerhead emergences ontheislandhasgenerally paralleled thedistribution ofnests(ABI,1987,1994).Incontrast, nestingsuccessbyloggerheads alongtheislandhastypically lackedgradients (ABI,1987,1994).Thus,therelatively highnumbersofloggerhead nestsobservedincertainareasareusuallyaresultofmoreturtlescomingashoreinthoseareasratherthanofmorepreferable nestingconditions beingencountered bythetuxtlesaftertheyemerged.Avarietyofenvironmental factors(i.e.,offshorebottomcontours, distribution ofreefs,typeandextentofdunevegetation, andhumanactivityonthebeachatnight)mayeffectloggerhead turtleemergence patternsandseveralhavebeenreportedtoaffectemergence patternsonHutchinson Island(ABI,1988,1989).Undoubtedly, acombination offactorsaccountsfortheoveralldistribution ofemergences andtherefore theoverallnestingpatternontheisland.NestingsurveysonHutchinson Islandwereinitiated inresponsetoconcernsthattheoperation oftheSt.LuciePlantmightnegatively impactthelocalseaturtlexookery.Previous

analysis, usinglog-likelihood testsofindependence (G-test;SokalandRohlf,1981)demonstrated thattheconstruction oftheplant'soffshoreintakeanddischarge structures significantly reducednesting-attheplantsiteduringconstruction years-1975,1981,1982,1983(ABI,1987).However,nestingattheplantconsistently returnedtolevelssimilartoor,greaterthanthoseatacontrolsiteinyearsfollowing construction.

During1991whenoffshoreconstruction wasrestricted almostentirelytodaylighthours,nests'were moreabundantattheplantsitethanatthecontrolsite.Datacollected through1998haveshownthatpowerplantoperation exclusive ofnighttime intake/discharge construction hashadnoapparenteffectonnesting.3.3.1.3Lon-TermTrendsinLoerheadTurtleNestinVariousmethodswereusedduringsurveyspriorto1981toestimatethetotalnumberofloggerhead nestsonHutchinson Islandbasedonthenumberofnestsfoundinthenine1.25km-longsurveyareas(ABI,1980a).Eachofthesemethodswassubsequently foundtoconsistently overestimate islandtotals(ABI,1987).Sincewhole-island surveysbeganin1981,ithasbeenpossibletodetermine theactualproportion oftotalnestsdeposited inthenineareas.ThishasaHowedextrapolation fromtheninesurveyareastotheentireislandforyearspriorto1981.From1981through1993thetotalnumberofnestsinthenineareasvariedfrom32.5to35.6percentofthetotalnumberofnestsontheisland.Thisisslightlyhigherthanthe31.3percent,whichwouldbeexpected, basedstrictlyontheproportion oflinearcoastline comprised bythenineareas.Usingthethirteen-year meanof33.81percent,estimates ofthetotalnumberofnestsonHutchinson Islandcanbecalculated bymultiplying thenumberofnestsinthenineareasby2.958.Thistechnique, whenappliedtotheninesurveyareasduringthethirteenyearsinwhichtheentireislandwassurveyed, producedwhole-island estimates within5.3percentoftheactualnumberofnestscounted.Becausetheproportion ofnestsrecordedintheninesurveyareasremainedrelatively constantoverthelastthirteenyears,thisextrapolation procedure providesafairlyaccurateestimateoftotalloggerhead nestingforyearspriorto1981,andisusedtogeneratedatapointsfor1971through1979inFigure6.Itisclearthatloggerhead-nesting activityonHutchinson Islandfluctuates considerably fromyeartoyear(Figure6).Annualvariations innestdensities alsoarecommonatotherrookeries, andmayresultfromnon-annual reproductive behavior.

Despitehighvariability, datacollected thxough1998suggestanoverallincreaseinnestingonHutchinson Islandsincesurveysbeganin1971.Totalnestingactivitywasgreatestduring1995when8184loggerhead nestswererecorded.

Norelationships betweentotalnestingactivityandpowerplantoperation orintake/discharge construction wereindicated byyear-to-year variations intotalnestingonHutchinson Island.3.3.1.4SeasonalPatternsofLoerheadTurtleNestinTheloggerhead turtlenestingseasonusuallybeginsbetweenmid-April andearlyMay,attainsamaximumduringJuneorJuly,andendsbymid-September (ABI,1987).Nestingactivityduring1998followedthissamepattern.Coolwaterintrusions frequently occuroverthecontinental shelfofsoutheast Florida duringthesummer(Smith,1982).Theseintrusions mayhavebeenresponsible forthetemporary declinesinloggerhead turtlenestingactivitypreviously observedonHutchinson Island(ABI,1994).Thoughnaturalfluctuations intemperature havebeenshowntoaffecttemporalnestingpatternsonHutchinson Island,therehasbeennoindication thatpowerplantoperation hasaffectedthesetemporalpatterns(ABI,1988).3.3.1.5Predation onLoerheadTurtleNestsSincenestsurveysbeganin1971,raccoonpredation hasbeenamajorcauseofturtlenestdestruction onHutchinson Island.Researchers atotherlocations havereportedraccoonpredation levelsashighas70tonearly100percent(Hopkinsetal.,1979).Raccoonpredation ofloggerhead turtlenestsonHutchinson Islandhasnotapproached thislevelduringanystudyyear,thoughlevelsforindividual 1.25km-longareashavebeenashighas80percent.Overallpredation ratesforsurveyyears1971through1977werebetween21and44percent,withahighof44percentrecordedin1973.Apronounced decreaseinraccoonpredation occurredafter1977andoverallpredation ratesforthenineareashavenotexceeded10percentsince1979.Adeclineinpredation ratesonHutchinson Islandmaybeattributable totrappingprograms, construction activities, habitatloss,anddisease.During1998,raccoonpredation levelswereextremely low,withonlyoneloggerhead nestinareasA-Sdepredated byraccoons(Figure7).Inpreviousyears(ABI,1994),predation ofturtlenestswasprimarily restricted tothemoreundeveloped portionsoftheisland.Ghostcrabshavebeenreportedbynumerousresearchers asimportant predators ofseaturtlenests(Hopkinsetal,1979;Stancyk,1982).ThoughturtlenestsonHutchinson Islandprobablyhavebeendepredated byghostcrabssincenestingsurveysbeganin1971,quantification ofghostcrabpredation didnotbeginuntil1983.Overallpredation ratesbyghostcrabshavevariedfrom0.1to2.1percentfrom1983-1998.During1998,threeloggerhead nestinareasA-Sweredepxedated byghostcrabs(Figure7).Nestsdestroyed byacombination ofraccoonandghostcrabpredation havebeenincludedasraccoonpredations inpreviousdiscussions.

Whenthesecombination predations areincludedascrabpredations, theoverallpredation ratesbyghostcrabsrangefrom0.1to4.7percent.During1998,nosuchcombination predations wererecorded.

3.3.1.61998GreenandLeatherback NestinSummIn1998,258greenturtleand77leatherback turtlenestswererecordedinthe36one-kmsegmentscomprising Hutchinson Island.Thegreenturtletotalrepresents anewrecordforHutchinson Islandgreenturtlenestingandasubstantial increasefromlastyear'stotals.1998wasalsoarecordyearforleatherback turtlenestingonHutchinson Island(Figures8and9).Althoughstrongyeartoyearfluctuations arecommon,thegeneraltrendsince1971mayreflectanincreaseinthenumbersofnestingfemalesintheHutchinson Islandarea.

3.3.1.7TrendsinGreenandLeatherback TurtleNestin~~~~~~Greenandleatherback turtlesnestonHutchinson Island,butinfewernumbersthanloggerhead turtles.Priorto1981,bothsurvey(nine1.25km-longsections) andinter-survey areasweremonitored forthepresenceofgreenandleatherback nests.Thirty-one kilometers ofbeachfromArea1southtotheSt.LucieInletwereincludedinthateffort.Duringwhole-island surveysfrom1981through1993,only2.6percent(7)oftheleatherback nests(n=266)andonly1.4percent(12)ofthegreenturtlenests(n=831)wererecordedonthefivekilometers ofbeachnorthofArea1.Therefore, previouscountsofgreenandleatherback nestswithinthe31kilometers surveyedprobablywerenotappreciably different fromtotaldensities fortheentireisland.Basedonthisassumption, greenandleatherback nestdensities maybecomparedamongallsurveyyears,except1980,whenlessthan15kilometers ofbeachweresurveyed.

Sincesurveysbeganin1971,thenumberofnestsobservedontheislandrangedfrom5to258forgreenturtlesandfrom1to77forleatherbacks (Figures8and9).Temporalnestingpatternsforthesespeciesdifferfromthepatternforloggerhead turtles.Greenturtlestypically nestonHutchinson Islandfrommid-JunethroughthefirstorsecondweekofSeptember.

Leatherback turtlesusuallybeginnestinginMarchorAprilandcontinuetonestthroughearlytomid-July.

Considerable fluctuations ingreenturtlenestingontheislandhaveoccurredamongsurveyyears(Figure8).Thisisnotunusualsincetherearedrasticyear-to-year fluctuations inthenumbersofgreenturtlesnestingatotherbreedinggrounds(Carretal.,1982).Despitethesefluctuations, datacollected through1998suggestanoverallincreaseinnestingsince1971andmay~~~reflectanincreaseinthenumberofnestingfemalesintheHutchinson Islandarea.During1998,greenturtlesnestedmostfrequently alongthesouthernhalfoftheisland.Thisisconsistent withresultsofprevioussurveys.Leatherback turtlenestdensities haveremainedlowonHutchinson Island,however,increased nestingduringrecentyears(Figure9)mayreflectanoverallincreaseinthenumberofnestingfemalesintheHutchinson Islandarea.

3.3.2INTAKECANALMONITORING

~~~~~~Entrainment ofseaturtlesattheSt.LuciePlanthasbeenattributed tothepresumedphysicalattractiveness oftheoffshorestructures housingtheintakepipesratherthantoplantoperating characteristics (ABI,1980band1986).Thevelocitycaps,whichaxesupported abovetheopeningstoeachintakepipe,eliminate verticalwaterentraimnent andsubstantially reducecurrentvelocities nearthestructures byspreading horizontal drawoverawiderarea.Evenwhenbothunitsareoperating atfullcapacity, turtlesmustactivelyswimintothemouthofoneofthepipesbeforetheyencounter currentvelocities sufficiently strongtoeffectentraimnent.

Consequently, aturtle'sentrapment relatesprimarily totheprobability thatitwilldetectandsubsequently enteroneoftheintakestructures.

3.3.2.11998CanalCatureSummIn1998,666seaturtleswerecapturedintheintakecanaloftheSt.LuciePlant.Capturesincluded393loggerheads, 268greenturtles,1leatherback, 2hawksbill, and2Kemp'sridleyturtles(Table1).3.3.2.2RelativeAbundance andTemoralDistribution Sinceintakecanalmonitoring beganinMay1976,3578loggerhead (including 222recaptures),

2432green(including 478recaptuxes),

21leatherback, 33Kemp'sridleys,and21hawksbill capturehavetakenplaceattheSt.LuciePlant.Annualcatchesforallspeciescombinedrangedfromalowof33in1976(paxtialyearofplantoperation andmonitoring) to933in1995.Exceptfor1993thxough1997,whenthegreenturtlewasthemostabundantspeciesinthecanal,loggerheads havedominated annualcaptures.

Since1977,thefirstfullyearofplantoperation, thenumberofloggerheads capturedeachyearrangedfrom62in1981to393in1998(Figure10).Numbershaveexhibited considerable year-to-year fluctuations withnopersistent trendsevident,althoughrecentyear'sdataaresuggestive ofapossibleincreasing trend.Thenumberofgreenturtlescapturedeachyearsince1977haverangedfrom3in1979toarecordhighof673in1995(Figure10).Increasing numbersofcapturesoverrecentyearsmayreflectanincreaseinthenumberofturtlesinhabiting thenearshore coastalareaneartheplantormaysimplyrepresent statistical variation.

Greenturtlecapturesweredownsharplyin1997,butshowedamodestreboundin1998.Additional yearsofcapturedatawillberequiredbeforeanylong-term trendscanbeestablished.

During1998,themonthlycatchofloggerheads rangedfrom10(November) to60(March),withamonthlymeanof32.7(Table2).Overtheentirehistoryofthecaptureprogram,monthlycatcheshaverangedfrom0to87,withthegreatestnumberofcapturesoccurring duringJuly1996.During1998,themonthlycatchofgreenturtlesrangedfrom7(July)to58(February),

withamonthlymeanof23.3(Table3).TheMarch1996catchof147greenturtlesisthelargestnumberofcapturesforthisspeciesforanymonthonrecord.Seasonalabundance patternsof10 greenturtleshavetypically beenmuchmorepronounced thanforloggerheads, withover50percentofallcapturesoccurring betweenJanuaryandMarch.In1995through1998,however,nosuchseasonalpatternwasevident,withcapturesdistributed moreorlessevenlythroughout theyear.Catchesofleatherbacks, hawksbills, andKemp'sridleyshavebeeninfrequent andscattered throughout theyears.Eachspecieshasshownratherpronounced seasonaloccurrences; over60percentofaHleatherbacks werecapturedinMarchandApril,over60percentofthehawksbills werecapturedbetweenJulyandSeptember, andalmost90percentoftheKemp'sridleyswerecaughtbetweenDecemberandApril.3.3.2.3Size-Class Distributions Thesize-class distribution forloggerheads removedfromtheintakecanalin1998ispresented inFigure11.Thesizeclassdistribution forgreenturtlesremovedfromtheintakecanalin1998aiepresented inFigure12.ABI(1994)presentssize-class dataforturtlesremovedfromtheintakecanalfrom1976-1993.

Theleatherback capturedin1998wasanadult,withastraight-linecarapacelength(SLCL)ofover121cm(Hirth,1980).Bothhawksbills capturedin1998wereadults(SLCL)63cm)(Witzell, 1983).BothKemp'sridleyscapturedin1998werejuveniles SLCL(60cm)

(Hirth,1980).3.3.2.4SexRatiosOfthe390loggerheads capturedin1998forwhichstraightlinecarapacelengthsareavailable, 276werejuveniles withastraightlinecarapacelength(SLCL)lessthanorequalto70cm,81wereadults(SLCL)85cm)and33weretransitional (SLCL71-85cm)(Hirth,1980).'helattergroupprobablyincludesbothmatureandimmatureindividuals.

Ofthe81individuals classified asadultsforwhomsexwasrecorded, 76werefemalesandfiveweremales,withfemalespredominating byaratioof15:1.Ofthe267greenturtlescapturedin1998forwhichstraightlinecarapacelengthsareavailable, 263werejuveniles orsub-adults (SLCL(83cm)(Whitherington andEhrhart,1989).Ofthe4adultgreenturtlescapturedin1998,2weremalesand2werefemales.ABI(1994)discusses sexratiodataforpreviousyears.3.3.2.5CatureEfficiencies Nettingmethodologies havebeenundercontinual reviewandrefinement asnetmaterials, configurations, andplacement bevariedinanefforttomiiiiinize seaturtleentrapment times.Additionally, alternative capturetechniques havebeenevaluated, andpotential deterrent systemstestedinthelaboratory.

Currentcaptureprocedures haveproventoprovideasafe,efficient, andcost-effective programforremovingentrapped turtlesfromtheintakecanal.Formaldailyinspections oftheintakecanalareconducted everydaythatcapturenetsaredeployed, andthenumber,locationandrelativesizeofentrapped turtlesarerecordedonfieldobservation forms.Betterutilization ofcurrentsandeddies,adjustments totethering lines,multi-11 netdeployments andincreased effortstohandcaptureturtleshavecontributed toreducedentrapment timesduringrecentyears.Entrapment timesmaybeextendedforturtlesswimmingpasttheA1Abarriernet(ABI;1987).BecausecaptureeffortswestoftheAIAbridgeweregenerally lesseffective thanthoseneartheintakeheadwalls, mostturtlesbreaching thebarriernetwerenotcaughtuntiltheyenteredtheintakewells.ofUnits1and2..Becauseoftheirrelatively smallsizes,virtually alltheturtlesreachingtheintakewellsaregreenturtles.During1998,5ofthe268greenturtlecaptures(1.8percent)occurredattheintakewells.Thesubstantial decreaseinthepercentage ofcapturesattheplantintakewellscomparedtothe1995figureof14.5percentisattributed totheeffectiveness ofthenewsmallmeshbarriernetinstalled eastofAIAinJanuary1996.During1998,99.1percentofallturtlesentrapped inthecanalwerecapturedeastoftheA1ABridge,547bytanglenetsand119byhandordipnetcapture.Theeffective confinement ofturtleseastofA1Ahasbeenamajorcontributor tothehighcaptureefficiency achievedduringrecentyears.Theinstallation ofanimprovedbarriernetcompleted inJanuary1996hasfurtherincreased captureefficiency bymoreeffectively confining turtlesofallsizestoasmallerareaeasttotheA1Abarriernet.3.3.2.6BarrierNetMaintenance Barriernetmaintenance iscriticalinreducingtheopportunity formortalities intheplantintakewellareaandinreducingresidence timesforturtlesintheintakecanalsystem.Dailyinspections areperformed fromasmallboattoremovefloatingdebrisandtorepairholesnearoratthewatersurface.Whenunderwater visibility conditions permit,aweeklyunderwater inspection isconducted.

Aformalinspection isconducted monthly,including holerepair,debrisremoval,andairlift'dredging ofaccumulated siltifneeded.Maintenance conducted in1998includedtherepairofanyholesinthemeshdiscovered duringthedaily,weeklyandmonthlyinspections andextensive debrisremovalandairliftdredgingofaccumulated sedimentconducted inNovember.

InSeptember, October,andNovember1998,largeinfluxesofjellyfish intotheintakecanalrequiredtheprimarybarriernettobeloweredperiodically, sometimes fordaysatatime,topreventthenetfromfailingundertheweightofaccumulated jellyfish.

Theloweringmechanism functioned asdesignedandnodamagewassustained.

3.3.2.7RelativeCondition TurtlescapturedaliveintheintakecanaloftheSt.LuciePlantwereassignedarelativecondition basedonweight,activity, parasiteinfestation, barnaclecoverage, wounds,injuriesandanyotherabnormalities whichmighthaveaffectedoverallvitality.

During1998,95.2%percent(373)ofallloggerheads foundinthecanalwerealiveandingoodcondition.

Only4.8percent(19)loggerhead capturesinvolvedindividuals infairorpoorcondition, andonewasdead.Ofthe268greenturtlesremovedfromtheintakecanalduring1998,254(94.8percent)wereingoodcondition, 14(5.2percent)wereinfairorpoorcondition, andnoneweredead.The2hawksbills, 2Kemp'sridleys,andtheleatherback capturedin1998wereallingoodcondition.

12 Relativecondition ratingscanbeinfluenced byanumberoffactors,somerelatedandothersunrelated toentrainment and/orentrapment intheintakecanal.Aratingofgoodindicates thatturtleshavenotbeennegatively impactedbytheirentrapment inthecanal,atleastasevidenced byphysicalappearance.

Althoughratingsoffairorpoorimplyreducedvitality, theextenttowhichentrainment andentrapment isresponsible isoftenindeterminable.

Insomeinstances, conditions responsible forlowerratings,suchasboatcollision orfisheries gearentanglement injuriesobviously weresustained priortoentrainment.

During1998,71ofthe666turtlescaptured(10.7percent)hadnotableinjuriessuchasmissingappendages, brokenormissingpiecesofcarapace, ordeeplacerations.

Manyofthesewereold,.well-healed wounds,anddidnotrequireveterinary attention.

Ofthe665liveremovalsduring1998,652werereleasedintotheoceanthedayofcapture.Nineturtles(allloggerheads) inobviousillhealthorsuffering seriousinjuriesweretransported toSeaWorldofFloridaortheMarinelife CenterofJunoBeachfortreatment andrehabilitation.

Twohadseriouscarapacedamage,presumably fromaboatcollision, onehadingestedmonofilament fishingline,andsixwereweak,lethargic, andemaciated whencaptured.

Fifteengreenturtleswithfibropapilloma tumorswereremovedfromthecanalin1998.Threeturtleswithextensive tumorsweretransferred totheFloridaDEPfortransportation toarehabilitation facility.

Twelveturtleswithminortumorsweretaggedandreleased.

Onegreenturtlewasheldovernight forinstallation ofasatellite-tracking transmitter andwaslaterreleased.

3.3.2.8Mortalities Seaturtlemortalities havebeencloselymonitored throughout thelifeofthecanalcaptureprogmminanattempttoassignprobablecausesandtakeappropriate remedialactiontominimizefutureoccurrences.

PreviousanalysesofcapturedataidentiTied drowninginnets(A1Abarriernet,UIDSbarrier,andtanglenets),drowningintheintakepipesduringperiodsofreducedintakeflow,injuriessustained fromdredgingoperations, andinjuriessustained fromthemechanical rakesusedintheintakewellsasprobablemortality factors(ABI,1987)(FPL,1995).Althoughdifficult toquantify, theentrapment andsubsequent demiseofinjuredorsickturtleshasprobablyaccounted foraportionofobservedmortalities.

Overtheentiremonitoring programhistory,135(3.8percent)ofthe3578loggerheads and52(2.1percent)ofthe2432greenturtlesentrapped inthecanalwerefounddead.Mortalities spannedtherangeofsizeclassesfor.loggerheads (SLCL=47.5-103cm),whileallgreenturtlemortalities involvedjuveniles lessthan42cminlength.ThefourKemp'sridleymortalities documented attheplantduring1987and1988weretheonlydeathsforthisspeciestodate;nodeadleatherback orhawksbill turtleshavebeenrecovered attheSt.LuciePlant.Modifications tocaptureprocedures, improvements tobarriernets,andvirtualelimination oflowflowconditions withinthecanalhaveresultedinasubstantial reduction inseaturtlemortalities overthelifeofthecanalcaptureprogram.Mortality rate,expressed asthepercentage oftotalcapturesinvolving deadanimals,declinedfrom7.8percentduringtheperiod1976-1984 to2.1percentsince1984,and1.0%since1990(Table1).13 In1998,oneturtle(aloggerhead) wasremoveddeadfromtheintakecanal,foranoverallmortality rateof0.15percent.

Theturtlewasfoundfloatingupagainstthe'A1Abarriernetduringaperiodwhentheprimarybarriernetwasloweredduetoajellyfish influx.Theturtlewasmoderately decomposed, andnocauseofdeathcouldbedetermined.

Inresponsetothe1995mortalities andthedramaticincreaseinintakecanalcapturesin1995,consultation wasinitiated withFPL,NRC,andtheNMFSunderSection7oftheEndangered SpeciesAct.Asaresultofthatconsultation, FPLhasdesignedandconstructed animproved, smallermeshbarriernetlocatedbetweentheA1Abarriernetandtheintakecanalheadwalls (Figure2).Construction ofthenetwascompleted inJanuary1996.ThisbarriernetpreventsturtlesfromreachingtheintakewellsorUIDSbarrierandincreases captureefficiency byconfining turtlestoasmallerareaoftheintakecanal.3.3.2.9RecatuxeIncidents SincetheSt.LuciePlantcaptureprogrambegan,mostturtlesremovedfromtheintakecanalhavebeentaggedandreleasedintotheoceanatvariouslocations alongHutchinson Island.Consequently, individual turtlescanbeidentified aslongastheyretaintheirtags.OverthehistoryoftheprogramattheSt.LuciePlant,700recaptures (222loggerheads and478greentuxtles)haveoccurred, andanumberofturtleshavebeenrecaptured morethanonce.Therecapture rateforgreenturtlesin1998was37percentandtherecapture rateforloggerheads wasonly5.3pexcent.Thelargenumberofgreenturtlerecaptures probablyreflectsthesaturation oflocalgreenturtlepopulations withturtlestaggedattheSt.LuciePlantandpossiblyindicates adifference insitefidelitybetweengreenturtlesandloggerheads.

Severalotherturtleswithtagscarshavealsobeenrecovered indicating thattheactualnumberofxecaptuxes maybehigher.3.3.3SUMMARYAgradientofincreasing loggerhead turtlenestdensities fromnorthtosouthalongthenorthernhalfofHutchinson Islandhasbeenshownduringmostsurveyyears.Thisgradientmayxesultfxomvariations inbeachtopography, offshoredepthcontours, distribution ofnearshore reefs,onshoreaxtiflcial

lighting, andhumanactivityonthebeachatnight.Lownestingactivityinthevicinityofthepowerplantduring1975andfrom1981through1983wasattributed tonighttime construction activities associated withinstallation ofpowerplantintakeanddischarge structures.

Nestingreturnedtonormalorabovenormallevelsfollowing bothperiodsofconstruction.

During1991,daytimeconstruction activities associated withvelocitycaprepairshadnoapparenteffectonnesting.Statistical analysesindicatethatpowerplantoperation, exclusive ofnighttime construction, hashadnosignificant effectonnestdensities neartheplant.In1998,7962loggerhead turtlenestswererecordedonHutchinson Island.Therehavebeenconsiderable year-to-year fluctuations inloggerhead nestingactivityonHutchinson Islandfrom1971through1998.Fluctuations arecommonatotherxookeries andmayresultfromnon-annual reproductive behavior.

Despitethesefluctuations, loggerhead-nesting activityhasremainedhighduringrecentyearsandmayreflectanoverallincreaseinthenumberofnestingfemalesintheHutchinson Islandarea.Norelationship betweentotalnestingontheislandandpowerplantoperation orintake/discharge construction wasindicated.

14 TemporalnestingpatternsoftheHutchinson Islandpopulation maybeinfluenced bynatural,largescalefluctuations inwatertemperature, suchasthoseproducedbythecoolwaterintrusions thatfrequently occuroverthecontinental shelfofsoutheast Floridaduringthenestingseason.However,localized fluctuations inwatertemperature associated withpowerplantoperation havehadnoapparenteffectonnesting.Sincenestingsurveysbeganin1971,raccoonpredation hasbeenoneofthemajorcausesofturtlenestdestruction onHutchinson Island.From1971through1977,overallpredation ratesintheninesurveyareaswerebetween21and44percent.However,apronounced decreaseinraccoonpredation occurredafter1977,andoverallpredation ratesintheninesurveyareashavenotexceededtenpercentsince1979.Decreased predation byraccoonsprobablyreflectsadeclineintheraccoonpopulation.

Moreyearsofsurveydatawillberequiredtodetermine iftheextremely lowlevelofraccoonpredation in1996through1998isanisolatedoccurrence orpartofacontinuing trend.Ghostcrabpredation ontheturtlenestsmaybemoresignificant thanpreviously documented butremainsrelatively minorcomparedtoraccoonpredation.

During1998,258greenturtleand77leatherback turtlenestswererecordedonHutchinson Island,arecordhighforbothspecies.Nestingactivitybythesetwospecieshasexhibited considerable annualfluctuations, ashasbeenrecordedatotherrookeries, buthasremainedrelatively highduringrecentyears.Thismayreflectanoverallincreaseinthenumberofnestinggreenandleatherback turtlesintheHutchinson Islandarea.During1998,393loggerheads, 268greenturtles,2hawksbills, 2Kemp'sridleys,andoneleatherback wereremovedfromtheSt.LuciePlantintakecanal.Sincemonitoring beganinMay1976,3578loggerhead, 2432green,21leatherback, 21hawksbill and33Kemp'sridleyturtleshavebeencapturedandtagged.Overthelifeofthemonitoring program,annualcatchesforloggerhead turtleshaverangedfrom33in1976(partialyearofplantoperation andmonitoring) toahighof393in1998.Yearlycatchesofgreenturtleshaverangedfrom0in1976to673in1995.Differences inthenumberofturtlesentrapped duringdifferent yearsandmonthsareattributed primarily tonaturalvariation intheoccunence ofturtlesinthevicinityoftheoffshoreintakestructures, ratherthantoplantoperation characteristics.

Size-class distributions ofloggerhead turtlesremovedeachyearfromthecanalhaveconsistently beendominated byjuveniles between50and70cminstraight-line carapacelength.Over75percentofallgreenturtlesentrapped inthecanalwerejuveniles 40cmorlessinlength.Forbothspecies,thelargestnumberofcapturesforallyearscombinedoccurredduringwinter,but,withtheexception of1995,andtolesserextent1996,theseseasonalpeaksweremuchmore'ronounced forgreenturtles.Thesexratioofloggerheads caughtinthecanalcontinued tobebiasedtowardsfemales.During1998,about95percentofallloggerheads andgreenturtlesremovedfromthecanalwerecategorized byphysicalappearance asbeingingoodcondition.

About10percentoftheturtlesremovedfromtheintakecanalduring1998hadsubstantial

injuries, andthevastmajorityofthosewereweHhealedandapparently sustained priortoentrapment.

Onceinthecanal,turtlesconfinedeastofA1Ahadverybriefresidency times.Thus15 therelativecondition ofmostturtleswasnotaffectedbytheirentrapment.

~~~~~~~~~~~~~~During1998,onlyonemortality wasxecordedintheintakecanal.Programmodifications, including continual surveillance oftanglenetsduringperiodsofdeployment, improvements totheintegrity ofthebarriernetsystem,andgreaterefforttohandcaptureturtleshavecontributed toasubstantial declineinseaturtlemortalities duringrecentyears.Thedesignandconstruction ofanimprovedbarriernetcompleted inJanuary1996wasexpectedtoreducemortalities andentrapment timesforturtlesintheintakecanal.Datasincethenindicatethatthenewbarriernetconfiguration hasbeenhighlyeffective inexcluding turtlesfromtheplantintakewells,buthasnotbeenaseffective inreducingtheoverallmortality rateasanticipated, althoughthe1998mortality rateof0.15%,thelowestmortality rateintheprogramshistory,wasanoutstanding achievement andahopefulsignforthefuture.16

4.0 LITERATURE

CITEDABI(AppliedBiology,Inc.),1978.Ecological Monitoring AtTheFloridaPower&LightCompanySt.LuciePlant,AnnualReport1977;VolumesIandII.AB-101.PreparedbyAppliedBiology,Inc.forFloridaPower&LightCompany,Miami.1980a.FloridaPower&LightCompany,St.LuciePlantAnnualNon-Radiological Environmental Monitoring Report1979.VolumesIIandIII,Bioticmonitoring.

AB-244.Preparedby.AppliedBiology,Inc.forFloridaPower&LightCompany,Miami.1980b.TurtleEntrainment Deterrent Study.AB-290.PreparedbyAppliedBiology,Inc.ForFloridaPower&LightCompany,Miami.1986.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1985.AB-563.PreparedbyAppliedBiology,Inc.forFloridaPower&LightCompany,JunoBeach.1987.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1986.AB-579.PreparedbyAppliedBiologyInc.forFloridaPower&LightCompany,JunoBeach.1988.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1987.AB-595.PreparedbyAppliedBiologyInc.-forFloridaPower&LightCompany,JunoBeach.1989.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1988.AB-596.PreparedbyAppliedBiology,Inc.forFloridaPower&LightCompany,JunoBeach.1994.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Monitoring Report.AB-631.PreparedbyAppliedBiology,Inc.,forFloridaPower&LightCompany,JunoBeach.Carr,A.,A.Meyan,J.Mortimer, K.BjorndalandT.Carr,1982.'urveys ofSeaTurtlePopulations andHabitatsintheWesternAtlantic.

NOAATechnical Memorandum NMFS-SEFC-91:1-82.

Davis,G.E.,andM.C.Whiting,1977.Loggerhead SeaTurtleNestinginEverglades NationalPark,Florida,U.S.A.Herpetologica 33:18-28.

FPL,1995.Assessment oftheImpactsoftheSt.LucieNuclearGenerating PlantonSeaTurtleSpeciesFoundintheInshoreWatersofFlorida.FloridaPower&LightCompany,JunoBeach,FL.Hirth,H.F.,1980.SomeAspectsoftheNestingBehaviorandReproductive BiologyofSea~~~Turtles.AmericanZoologist 20:507-523.

17 Hopkins,S.R.,T.M.Murphy,Jr.,K.B.StansellandP.M.Wilkinson, 1979.BioticandAbioticFactorsAffecting NestMortality intheAtlanticLoggerhead Turtle.Proceeding AnnualConference ofSoutheastern FishAndWildlifeAgencies32:213-223.

QuantumResources Inc.,1995.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1994.PreparedbyQuantumResources Inc.forFloridaPower&LightCompany,JunoBeach,FL.1996.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1995.PreparedbyQuantumResources Inc.forFloridaPower&LightCompany,JunoBeach,FL.1997.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1996.PreparedbyQuantumResources Inc.forFloridaPower&LightCompany,JunoBeach,FL.1998.FloridaPower&LightCompany,St.LucieUnit2AnnualEnvironmental Operating Report1997.PreparedbyQuantumResources Inc.forFloridaPower&LightCompany,JunoBeach,FL.Smith,N.P.,1982.Upwelling inAtlanticShelfWatersofSouthFlorida.FloridaScientist

~~~~~~~~~~~~45(2):125-138.Sokal,R.R.andF.J.Rohlf,1981.Biometry.

ThePrinciples andPracticeofStatistics inBiological Research.

S.H.FreemanandCompany,SanFrancisco.

859pp.Stancyk,S.E.,1982.Non-Human Predators ofSeaTurtleandTheirControl.Pages139-152inBjorndal, K.A.,ed.BiologyandConservation ofSeaTurtles.Smithsonian Institution Press.Washington, DCWitherington, B.E.andL.M.Ehrhart,1989.StatusandReproductive Characteristics OfGreenTurtles(Chelonia

~mdasNestinginFlorida.Pages351-352inOgren,L.,F.Berry,K.Bjorndal, H.Kumpf,R.Mast,G.Medina,H.ReichartandR.Witham,editors.Proceeding oftheSecondWesternAtlanticTurtleSymposium.

Mayaguez, PuertoRico,12-16October1987.NOAATechnical Memorandum NMFS-SEFC-226.

Wlll,.N.1993.SpPl9lIDLED9NISNNS~Simbricata (Linnaeus, 1766).FAOFisheries

Synopsis, 137:1-78.18 FLORIDAGULFOFMEXICOic~iZy0-N-OKEECHOBEE OSTLUCIEPLANTFigure1.LocationofSt.LuciePlant20 HUTCHINSONISLANDINDIANRIVERIMCCOiLBIGMUOCREEK(/()Qi0ONII1<<.WTAKE~WEI.LSgPguOgnElk5cQ=AW~%frIIi0~IfAAAC~~IIAKEHEAOWNLSAIA$'E'SIIBARBERSAHKIEANETSCKAHARIGE PIPESATLANTICOCEANt41AKESTRVCIIKIES INDIANRIVERFigure2.St.LuciePlantCoolingW'aterIntakeandDischarge System21 ooFT.PIERCEINLET'6AI0FQHQISTATEHWYA1AOPaQRSTUFPLST.LUCIEPLANTUNITOFCURRENTSURVEYDIERIVERwQXYODHQHGGHHST.LUCIEINLETDRAWINGNOTTOSCALEfg4VO50l25f fSAOIFigure3.Designation andLocationofNine1.25-KmSegmentsandThirty-Six 1-KmSegmentsSurveyedforSeaTurtleNesting,Hutchinson Island.1971-1998.

22 1000%90.0%~GPP%7PP%U6ppV5pp0400Pal300%20P300%ppABCDEFGHIJKLMN0PQRSPowerPlantFigure4.NumberofLoggerhead TurtlesNestsandEmergences forAreasAThroughS,Hutchinson Island,AprilThroughSeptember 1998.23 12008nestsIIemergences 100048000600400200ABCDEFGHIJKLMN0PQRSAREAPowerPlantFigure5.Loggerhead TurtleNestingSuccess(Percentage ofEmergences Resulting inNests)forAreasAThroughS,Hutchinson Island,AprilThroughSeptember 1998.24 90008000-70006000z5000040003000K20001000-71727374757677787980818283848586878889909192939495969798Figure6.NumberofLoggerhead TurtleNests,Hutchinson Island1971Through1998.Valuesfor1971Through1979AreEstimates (SeeText);Valuesfor1981Through1998AreFromWholeIslandSurveys.25 8CRABSONLY~RACCOONSONLYarn10ABCDEFGHIJKLMNgPQRSAREAPowerPlantTFigure7.Percentage ofLoggerhead TurtleNestsPredatedbyRaccoonsand/orGhostCrabsinAreasAThroughS,Hutchinson Island,AprilThroughSeptember 1998.26 300250F200z150gl005071727374757677787980818283848586878889909192939495969798Figure8.NumberofGreenSeaTurtleNests,Hutchinson Island,1971Through1998.Valuesfor1971Through1979AreEstimates (SeeText).Valuesfor1981Through1998ArefromWholeIslandSurveys.27 9080-70C6K040-30K201071727374757677787980818283848586878889909192939495969798Figure9.NumberofLeatherback TurtleNests,Hutchinson Island,1971Through1998.Valuesfor1971Through1979AreEstimates (SeeText).Valuesfor1981Through1998ArefromWholeIslandSurveys.28

800700~LOGGERHEAD

~GREEN600g50000300-200.100-7677787980818283848586878889909192939495969798Pigure10.NumberofLoggerhead andGreenTurtlesRemovedEachYearfromtheIntakeCanal,St.LuciePlant,1976Through1998.29 1009080-7060g50302010(4141-4546-5051-5556-6061-6566-7071-7576-8081-8586-9091-9596-100101-105106-110)110SIRAIGHTSTANDARDCARAPACELENGTH(cm)Figure11.SizeDistribution (SSCL)ofLoggerhead Turtles(N=391)RemovedfromtheIntakeCanal,St.LuciePlant,1998.30

7060-50"4020108A8488888'P8S88IIIIIfIIIII1II8R888g8STRAIGHTSTANDARDCARAPACELENGTH(cm)Figure12.SizeDistribution (SSCL)ofGreenTurtles(N=267)RemovedfromtheIntakeCanal,St.LuciePlant,1998.31 6.0TABLES32

'-YEAR.Loggerhead

-SpeciesLeatherbaek Hawksbill---

=--'..Kemp'sRidley.--'.=.-Total-1976197719781979198019811982198319841985198619871988198919901991199219931994199519961997199833(4)80(5)138(19)172(13)116(5)62(5)101(16)119(4)148(3)157(4)195(27)175(11)134(6)111(4)112(1)107(1)123(2)147164254(1)349(3)188393(1)5(2)6(1)3(1)10(3)32(2)823(4)69(2)14.22(1)3542(2)17(1)20(2)1261(2)179(1)193(4)673(15)549(4)191(5)26816(2)5(2)233(4)86(7)148(20)175(14)126(8)97(7)110(16)142(8)220(5)172(4)220(28)218(13)181(10)133(5)132(3)121(1)187(4)337(1)361(4)933(16)906(7)382(5)666(1)Total3578(135)AnnualMean*162.6*Excludes1976artial2432(52)110.5earoflantoeration.211.0211.034(4)1.55420(191)275.1Table1.TotalNumberofCapturesand(NumberofDead)TurtlesRemovedfromtheIntakeCanal33

MonO>NumberofCapturesPercentofStandardAttCstnurmMnimumMaximum"Mean:Deviation 1998JanuaryFebruaryMard>AprilMayJuneJulyAugustSeptember OctoberNovemberDecember42133535436430436440532419419312516211.9%9.4%10.0%10.3%8.6%10.3%11.4%9.1%5.5%5.4%3.5%4.6%39346047404287431927151319.115.216.116.513.816.518.414.78.88.85.77.410.28.414.712.710.411.120.112.25.26.33.94.1362860472926574317271013TotalMeanStd.Deviation 35458713.44.639332.816.3*Firstfullyearofplantoperation.

Anadditional 33loggerheads werecapturedduring1976.Table2.TotalNumberofLoggerhead TurtlesRemovedBachMonthfromIntakeCanal,St.LuciePlant,1977-1998.34 Number'of.

=..::,':==:-'.Percentof-

.--':='-,".;-'-::--,.,;,-.'.'-."..',Standard:

-.Montk'i'::,-,,::::

'.Captures

'...:."Alt'Cauptuees.:"..Minimum:Ma'xlmutni',Meiin:

-':Beylation:

1998:,JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptember OctoberNovemberDecember28428937021018013712515114819815019011.7%11.9%15.2%8.6%7.4%5.6%5.1%6.2%6.1%8.1%-6.2%7.8%000000000000596414764915261647754426812.915.513.118.316.835.69.517.38.220.26.212.65.714.16.915.26.717.89.015.46.810.88.615.82558302035167231025109TotalMeanStd.Deviation 243201479.23.426822.314.4"Firstfullearoflantoeration.Table3.TotalNumberofGreenTurtlesRemovedEachMonthfromtheIntakeCanal,St.LuciePlant,1977-1998.

35 V0 ANNUAL%2AZRONM~22ITAL OPERATING REPORTPARTII

1.0INTRODUCTION

TheSt.LucieUnit'2Environmental Protection Plan(EPP)requiresthesubmittal ofanannualreportforvariousactivities attheplantsiteincluding thereporting onseaturtlemonitoring programsandothermattersrelatedtoFederalandStateenvironmental permitsandcertifications.

2.0 SEATURTLEMONITORING

ANDASSOCIATED ACTIVITIES Surveillance andmaintenance ofthelightscreentomininuzeseaturtledisorientation asrequiredbySection4.2.4oftheEPPisongoing.Thevegetation lightscreenlocatedonthebeachdunebetweenthepowerplantandtheoceanisroutinely surveyedtodetermine itsoverallvitality.

Thevegetation lineissurveyedforanygapsoccurring frommortality, whichwouldresultinunacceptable lightlevelsonthebeach.Trees,vegetation, orshadeclothsarereplacedasnecessary tomaintaintheoverallintegrity ofthelightscreen.Plantparkinglotlightingisalsodesignedandmaintained tomirumizelightlevelsonthebeach.3.0TAPROGGECONDENSER TUBECLEANINGSYSTEMOPERATION ATaproggecondenser tubecleaningsystem(CTCS)becameoperational onSt.LucieUnit2inJanuary1996andonUnit1inJuly1996.Thissystemutilizesspongeballs,approximately 24mmindiameter, tocleanthecondenser tubesthroughwhichseawaterflowstocoolsteamafteritspassthroughtheplant'sturbines.

Thissystemimprovesplantperformance whilereducingtheneedforchemicaltreatments suchandbiocidesorchlorinetocontrolbiofouling.

Normally, theSt.LucieCTCSutTiizesabout1800spongeballs,whichamcontinually recirculated througheachoffour"waterboxes"oneachunit.Thesespongeballsareretainedinthesystembyaballstrainerlocatedontheoutletofeachwaterbox.Theballstrainers (meshsize5mm)areopenedroutinely todischarge debris,whichcandecreaseflowandobstructspongeballmovementthroughth'esystem.Thespongeballsarecollected priortoopening,orbackflushing, theballstrainers.

Atthattime,thespongeballsareexaminedandreplacediftheyareworntothepointthattheycannolongereffectively cleanthecondenser tubes.Spongeballinventories andestimates ofspongeballlosstotheenvironment havebeenperformed sincesystemstart-uponbothunits.Numberofballstrainerbackflusheshasalsobeentracked.Inaddition, dailybeachsurveyshavebeenperformed onplantproperty(approximately 2.5miles)tonoteanyspongeballsthatmayhaveappearedasaresultoflossfromtheplant.Thissurveyareahasbeenextendedduringtheturtle-nesting seasontoalmost12miles.Theresultsoftheprogramfor1998arepresented inTable1.LargerspongeballlossesoccurredonUnit2fortheyear.Theselossesareprobablyrelatedtothefactthat1998represents theendoffuelcycleforthatunit.Estimated spongeballlossfrombothunitswas20.2ballsperdayfor1998.Fiftyspongeballswerefoundwholeintheenvironment neartheplant.Thisisanincrease36 overpreviousyears,butthenumberindicates thatfewballsactuallyreachtheenvironment whole.~~~~~~~~~~~~~~~Figure1indicates thatestimated spongeballlossgenerally increased throughthemonthofAprilof1998.Averagedailyballlossin1998increased fromthe1996and1997totals(Figure2).Itisbelievedthatmuchofthelossesarecausedbyincreased growthinsidethewaterboxes.

Newcoatingsonthesesurfacesarebeingusedtotrytoeleviatethisproblem.ThesecoatingwereappliedtoUnit2inDecember1998.Ifthecoatingproveseffective itwillbeappliedtoUnit1inSeptember 1999.4.0OTHERROVIINEREPORTSThefollowing itemsforwhichreporting isrequiredarelistedbysectionnumberfromtheplant'sEnvironmental Protection Plan:5.4.1(a)EPPNONCOMPLIANCES ANDCORRECTIVE ACTIONSTAKENNononcompliance's underEPPSection5.4.1(a)weredetermined tohaveoccurredduring1998.5.4.1(b)CHANGESINSTATIONDESIGNOROPERATION TESTSANDEXPERIMENTS INACCORDANCE WITHEPPSUBSECTION 3.1FPLletterI98-180transmitted therequestformodification ofWastewater PermitApplication toFDEP.Themodification includestheuseofbiocideintheplantclosedcoolingwatersystemsandtheuseofdimethylamine andcarbohydrazide intheplantsteamgenerator blowdown.

Thisletterwastransmitted June26,1998.5.4.1(c)NONROUTINE REPORTSSUBMHTEDTOTHENRCFORTHEM~1998INACCORDANCE WITHEPPSUBSECTION 5.4.22.Reportconcerning themortality LeastTernsattheplantNuclearTrainingCenterJuly6,1998andJuly17,1998.Deathsoccurredinthebuilding's drainagesystemduringheavyrainfall.

EventswerereportedtoNRCbyFPLletterI98-196onJuly23,1998.Reportconcerning anincreaseofjellyfish andsubsequent effectofplantoperation onSeptember 9,1998;reportedtotheNRCbyFPLletterL-98-250onOctober1,1998.37

TABLE11998ST.LUCIEPLANTCONDENSER TUBECLEANINGSYSTEMSUMIVCARY

-.-',.MONS'"-'i

.'.:;STRAD';BACKPLUSHES;:::--,::",.:,

.:"',:.UNIT1~'--'.:"-"""

.UMI;:-:.',.-.;

',:;:.:~PALMATED BA'LL:XQSS;.:

'-;;:.',

BAPS;FOUND'

,";.ON-'THESEACH

;:.:i

-':JanuaryFebruaryMarch102222262541698627613AprilMay0"2529241242852580June24+22+++July3323130586AugustSeptember October29253127202366114129483228NovemberDecember242562376229759Total1972341853551050Duetopoorspongeballrecovery, strainers werenotback-flushed.

Unitwasdown-powered,waterboxes takenoutofserviceformanualremovalofgrowthandballs.Unit1systemshutdownduringrefueling, 1/1to1/19/98.Unit2systemshutdownduringrefueling, 11/6to12/12/98.

Netgainininventory.

504540C3530)2s20gis10JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDECMONTHFigureI.Estimated AverageDailySpongeBallLossbyMonthfromSt.LuciePlant(BothUnits)for1998.39 25200151019961997YEAR1998Figure2.AverageDailySpongeBallLossfromtheSt.LuciePlant(BothUnits)SinceSystemStart-Up(January1996)40