ML17229B001

Technical Evaluation Rept on 'Submittal-Only' Review of IPEEE at St Lucie Nuclear Plant,Units 1 & 2.

ML17229B001
Person / Time
Site:	Saint Lucie
Issue date:	01/31/1998
From:	KAZARIANS M, MOSLEH A, SEWELL R T ENERGY RESEARCH, INC., External (Affiliation Not Assigned), MARYLAND, UNIV. OF, COLLEGE PARK, MD
To:	NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES)
Shared Package
ML17229A999	List: ML17229B000 ML17229B001 ML17229B002
References
CON-NRC-04-94-050, CON-NRC-4-94-50 ERI-NRC-95-504, NUDOCS 9902020322
Download: ML17229B001 (103)

Text

ERIINRC95-504TCCHNICRL CVRLURTION RCPORTONTH6"SUBMITTAL-ONLY" 86VlGLUOFTH6INDIVIDURL PLRNTCXRMINRTION OFtXTGRNRLEVENTSRTST.LUCICNUCLGRRPLRNT,UNITS1RND2FINALREPORTCompleted:

January1997Final:January1998EnergyResearch, inc.P.O.Box2034Rockville, Maryland20847-2034 WorkPerformed UndertheAuspicesoftheUnitedStatesNuclearRegulatory Commission OfficeofNuclearRegulatory ResearchWashington, D.C.20555ContractNo.04-94-050 r.:."...Vi902020322'~.990g2~awe)C~

mm~~;,+PDRADOCV.OSOOOSSSP'PDR ERI/NRC95-504TECHNICAL EVALUATION REPORTONTHE"SUBMITTALQNLY" REVIEWOFTHEINDIVIDUAL PLANTEXAMINATION OFEXTERNALEVENTSATST.LUCIENUCLEARPLANT(UNITSIAND2)FINALREPORTCompleted:

January1997Final:January1998M.Khatib-Rahbar Principal Investigator Authors:R.T.Sewell,M.Kazarians',

A.Mosleh-',

andA.S.KuritzkyEnergyResearch, Inc.P.O.Box2034Rockville, Maryland20847WorkPerformed UndertheAuspicesofthe..UnitedStatesNuclearRegulatory Commission OfficeofNuclearRegula'.ory ResearchWashington.

D.C.20555ContractNo.04-94-050

'azarians andAssociates, 425EastColoradoStreet,Suite545.Glendale, CA91205'niversity ofMaryland, Deparunent ofMaterials andNuclearEnginceriiig, CollegePark.MD20742 I~ap.%fg,~

TABLEOFCONTENTSEXECUTIVE SUMMARYPREFACE...ABBREVIATIONS

~~~~~~~~~~~~~~VlXll...XlllINTRODUCTION....

1.1PlantCharacterization 1.2OverviewoftheLicensee's IPEEEProcessand1.2.1Seismic1.2.2Fire..1.2.3HFOEvents1.3OverviewofReviewProcessandActivities...

1.3.1Seismic.....................

1.3.2Fire..1.3.3HFOEventsIinportant Insights....

~~~~~~~~~~~~~~234456688~~10101111~~~~~~~~~1314141414151515valuations.....

~~~~1616~~~~~~~0~.=..-..-1718181919~~~~~~~~~~~~~~~~~~~~~~~~~~I~~2021~~~~~~~~~~21CONTRACTOR REVIEWFINDINGS2.1Seismic.~..2.1.1OverviewandRelevance oftheSeismicIPEEEProcess.2.1.2SuccessPathsandComponent List..2.1.3Non-Seismic FailuresandHumanActions2.1.4SeismicInput2.1.5Structural Responses andComponent Demands2.1.6'creening Criteria..2.1.7PlantWalkdownProcess2.1.8Evaluation ofOutliers2.1.9RelayChatterEvaluation 2.1.10SoilFailureAnalysis2.1.11Containment Performance Analysis..2.1.12Seismic-Fire Interaction andSeismically InducedFloodE2.1.13Treatment ofUSIA<52.1.14PeerReviewProcess2.1.15SummaryEvaluation ofKeyInsights22Fire.....2.2.1OverviewandRelevance oftheFireIPEEEProcess...2.2.2ReviewofPlantInformation andWalkdown2.2.3Fire-Induced Initiating Events....2.2.4Screening ofFireZones...2.2.5FireHazardAnalysis2.2.6FireGrowthandPropagation 2.2.7Evaluation ofComponent Fragilities andFailureModes2.2.8FireDetection andSuppression 2.2.9AnalysisofPlantSystemsandSequences............

EnergyResearch, Inc.fERI/NRC95-504 goI142.32.4~~~~~~~~~~~~~~~~~~~~~~~\~~~\~~~~~N~~~2.2.10CoreDamageFrequency Evaluation

.2.2.11AnalysisofContainment Performance....

2.2.12Treatment ofFireRiskScopingStudyIssues2.2.13USIA%5IssueHFOEvents2.3.1HighWindsandTornadoes 2.3.1.1GeneralMethodology

..2.3.1.2Plant-Specific HazardDataandLicensing Basis2.3.1.3'ignificant ChangesSinceIssuanceoftheOperating License2.3.1.4Significant FindingsandPlant-Unique Features2.3.1.5HazardFrequency 2.3.1.6BoundingAnalysis...2.3.2ExternalFlooding...

2.3.2.1GeneralMethodology

....................

2.3.2.2Plant-Specific HazardDataandLicensing Basis2.3.2.3Significant ChangesSinceIssuanceoftheOperating License2.3.2.4Significant FindingsandPlant-Unique Features2.3.2.5HazardFrequency 2.3.3Transportation andNearbyFacilityAccidents

.....2.3.3.1GeneralMethodology

....2.3.3.2Plant-Specific HazardDataandLicensing Basis2.3.3.3Significant ChangesSinceIssuanceoftheOperating License..2.3.3.4Significant FindingsandPlant-Unique Features2.3.3.5HazardFrequency 2.3.4Lightning andOthersGenericSafetyIssues(GS1-147, GSI-148andGSI-172).....

2.4.1GSI-147,"Fire-Induced Alternate Shutdown/Control PanelInteraction 2.4.2GSI-148,"SmokeControlandManualFireFightingEffectiveness"

.2.4.3GS1-156,"Systematic Evaluation Program(SEP)"....2.4.4GS1-172,"Multiple SystemResponses Program(MSRP)"222222232424242525252526262626272727282828292930303131313135OVERALLEVALUATION ANDCONCLUSIONS

....3.1Seismic.3.2Fire...3.3HFOEvents42IPEEEINSIGHTS, IMPROVEMENTS, ANDCOMMITMENTS 4.1Seismic.4.2Fire...~~~~~~~~4.3HFOEvents...

~~~454547475IPEEEEVALUATION ANDDATASUMMARYSHEETS...........

EnergyResearch, Inc.ERI/NRC95-504 1

6REFERENCES................

55EnergyResearch, Inc.1VERI/NRC95-504 LISTOFTABLESTable3.1Comparison ofFPL'sSite-Specific SeismicIPEEEProgramVersusNUREG-1407 Recommended Guidelines foraReduced-Scope SeismicEvaluation

.40Table5.1ExternalEventsResults49Table5.2SSMSeismicFragility

......50Table5.3PWRSuccessPathOverviewTable.........

~.....'.51Table5.4PWRSeismicSuccessPaths52Table5.5'WRAccidentSequenceOverviewTable-ForFirePRAOnly..'...........

53'Table5.6PWRAccidentSequenceDetailedTable-FirePRAOnly54EnergyResearch, Inc.ERI/NRC95-504 EXECUTIVE SUMMARYThistechnical evaluation report(TER)documents a"submittal-only" reviewoftheindividual plantexamination ofexternalevents(IPEEE)conducted fortheSt.LucieNuclearPlant,Units1and2.Thistechnical evaluation reviewwasperformed byEnergyResearch, Inc.(ERI)onbehalfoftheU.S.NuclearRegulatory Commission (NRC).Thesubmittal-only reviewprocessconsistsofthefollowing

'tasks:Examineandevaluatethelicensee's IPEEEsubmittal and'irectly relevantavailable documentation.

Developrequestsforadditional information (RAls)tosupplement orclarifythelicensee's IPEEEsubmittal, asnecessary.

Examineandevaluatethelicensee's responses toRAIs.Conductafinalassessment ofthestrengths andweaknesses oftheIPEEEsubmittal, anddevelopreviewconclusions.

ThisTERdocuments ERI'squalitative assessment oftheSt.LucieIPEEEsubmittal, particularly withrespecttotheobjectives described inGenericLetter(GL)88-20,Supplement No.4,andtheguidancepresented inNUREG-1407.

FloridaPowerandLightCompany(FPL)isthelicenseeofSt.LucieUnit1(St.Lucie-1)andSt.LucieUnit2(St.Lucie-2).

TheSt.LucieIPEEEsubmittal considers seismic;fire;andhighwinds,floodsandother(HFO)externalinitiating events.TheSt.LucieIPEEEwasperformed andreviewedbylicenseeandcontractor personnel.

Licensee's IPEEEProcessWithrespecttotheseismicIPEEE,St.LucieNuclearPlantisassignedtothereduced-scope seismicreviewcategoryinNUREG-1407.

FPLelectedtoimplement asite-specific programforconducting theseismicIPEEEofSt.LucieNuclearPlant.Thesite-specific programwasdeveloped primarily inresponsetoGL8742forresolution ofUnresolved ShfetyIssue(USI)A-46atTurkeyPoint,Units3and4,andatSt.LucieUnit1.St.LucieUnit2isnotaUSIAA6plant;nonetheless, thesamesite-specific approachwasproposedforitsseismicIPEEE.Thesite-specific programrepresents a"scaled-back" approachtoUSIA-46resolution.

Aftermeetingsandcorrespondence.

withFPL,theNRCneverdesignated itsapprovalofthesite-specific programforIPEEEresolution.

Nonetheless, FPLproceeded withuseofitssite-specific programasthebasisforconducting theseismicIPEEE.Thesite-specific seismicadequacyevaluations conducted forSt.LucieUnits1and2reliedprimarily onaplantwalkdownthatfocusedoncomponent anchorage capability andthepotential foradverseseismic-induced spatialinteractions..A safeshutdownequipment list(SSEL)wasdeveloped basedonasuccesspaththatassumeslossofoffsitepower(LQSP).Thesubmittal doesnotdescribethesuccesspathnordoesitpresentasuccesspathlogicdiagram.Theevaluation approachdoesnotexplicitly addressasmalllossofcoolantaccident(LOCA).Allcomponents intheSSELthathadnotbeenpreviously verifiedashavingadequateseismiccapacitywerewalkeddownbytheseismicreviewteam(SRT)~Theseismicreviewteamuseditsjudgmentinassessing adequacyofseismicanchorage capacityandinidentifying spatialinteraction concerns.

Components withobviously ruggedanchorage werescreenedout;components withquestionable seismicanchorage wereEnergyResearch, Inc.viERI/NRC95-504 ra"jg+*<."~"L-E/pl[r.P.'C~w identified aspotential outliers.

Spatialinteraction concernswerealsoidentified aspotential outliers.

Thepotential outlierswereanalyzedinfurtherdetail,inordertomakeafinaloutlierdesignation.

Resolutions wereproposedfor,eachdesignated outlier.Table3.1ofthisTER'compares thefeaturesofFPL'ssite-specificIPEEEprogramagainsttheelementsofareduced-scope evaluation thathavebeenrecommended inNUREG-1407.

Thetableindicates thatFPL'sprogramaddresses onlyasubsetoftherecommended items/guidelines.

Themostsignificant differences inthetwoevaluation approaches arejudgedtobe:alesserscopeofcomponents intheFPLapproach; alimitedtreatment ofhumanactionsintheSt.Luciestudy;andnotreatment ofcontainment systemsintheFPLprogram.Inaddition, theformatfordocumenting theseismicIPEEEhasnotfollowedtherecommendations ofNUREG-1407.

Itisimportant tonotethat-basedonfindingsofasiteaudit(whichinvolvedaninspection ofFPL'sTurkeyPointNuclearPlant),andpendingfollow-up actionbythelicensee-theNRChasreachedclosureonUSIAA6forSt.Lucie-1.Toasignificant degree,theNRC'sresolution ofUSIA46concernshasservedasdirectbasisforformulating corresponding reviewfindingsinthisTERforsimilarIPEEEconcernsatSt.Lucie,Units1and2.ForthefireIPEEE,thelicenseehasconducted anextensive anddetailedanalysisoffireeventsatSt.Lucie.AppendixRdocumentation hasbeenusedtoestablish fire-related plantfeatures, aswellasfirezonesandareas.Inadditiontosafeshutdownequipment definedbyAppendixR,equipment modeledintheprobabilistic riskassessment (PRA)wereincludedinthefireanalysis.

Tosupportthefireanalysis, thelicenseehasconducted awalkdownofthefacility, usingengineers familiarwiththeplantandwithfireanalysis.

ThefireIPEEEfreezedateisDecember1993;thisdatehasbeenusedasthecut-offdateforalldocumentation describing theplant.Aconsulting firmwithe'xperience infireriskanalysishasassistedFPLanalystsinthepreparation ofthefireanalysis.

Thelicenseehasusedfire-induced vulnerability evaluation (FIVE)methodology andassociated firefrequency andfailuredatatoevaluatethefirerisk.Simplemodelshavebeenusedtoevaluatefiredamageandhumanrecoveryactions.Tokeeptheanalysissimple,noneoftheanalysespresented takesintoaccountthespecificfireprotection featuresforagivenarea,northespecificoperatoractionsforafirescenario.

Forredundant trainfailurefrequency evaluation, thePRAmodelsanddataoftheplanthavebeenused.Thelicenseehassubmitted aplanforAppendixRcompliance andhasaddressed themajorityoftheissuesraisedaspartofthatplan,withsupporting analysis.

Somefireareasandredundant cablesandequipment areprotected byThermo-lag.

Theeffectiveness ofThermo-lag anditsimportance atSt.LucieNuclearPlantarecurrently underinvestigation bythelicensee.

FortheHFOIPEEE,thegeneralmethodology utilizedbythelicenseeconformstothatpresented inNUREG-1407 fortheanalysisofotherexternalevents.Thelicenseehasperformed adetailedanalysisofhighwinds,externalflooding, andtransportation andnearbyfacilityaccidenthazards.Additionally, theotherexternaleventshavebeenevaluated toensurethattherearenohazardsuniquetotheplant.Amongtheseotherexternalevents,lightning hasbeenanalyzedingreaterdetail.KeyIPEEEFindingsFromtheseismicIPEEE,theprincipal findingsconsistofqualitative walkdowninsights, andfewquantitative findingshavebeenreported.

Theseismicadequacyevaluation forSt.Lucie-1revealedanumberofoutliersforwhichsafetyenhancements havebeenproposedinresponsetoUSIA-46.Inaddition, thelicenseeisundertaking follow-up actionstoimplement astrictseismichousekeeping programinresponsetoconcernsidentified bytheNRCinitsUSIA-46reviewprocess.Enhancements forIPEEE-onlycomponents (i.'e.,components outsidethescopeofUSIAA6,butwithinthescopeofIPEEE)wereEnergyResearch, Inc.viiERI/NRC95-504

It><."pihAM~~~VWF" notaddressed.

ForSt.Lucie-2,therewerenoconcernsidentified fortheequipment, providedawalkdownofwall-mounted transformers wouldbeperformed, andthatsuchtransformers wouldbesecuredasnecessary.

Again,noenhancements wereaddressed forIPEEEwnly components.

Withrespecttofireevents,thelicenseehasreachedtheoverallconclusion thattherearenosignificant firevulnerabilities atSt.Lucie.Withtheexception ofthecontrolroom,cablespreading roomandthe"B"switchgear room,allfirezonesandareaswerescreenedoutbasedona10perreactor-year (ry)coredamagefrequency (CDF)criterion.

TheCDFsforcontrolroomfireswereconcluded tobe7.49F10'/ryand5.90x10'/ry forUnits1and2,respectively.

Forthecablespreading rooms,thecoredamagefrequencies weredetermined tobe6.95x10'/ryand5.64x10'/ry forUnits1and2,respectively.

Forbothareas(i.e.,controlroom'andcablespreading room),thelicenseecitesseveralconservative assumptions infireoccurrence rateandfireseverity, andconcludes thatthesetwoareasdonotposeavulnerability.

TheCDFforafireinthe"B"switchgeai rooaiwasconcluded tobe4.30x10'/ry and4.48x10~/ryforUnits1and2,respectively.

Firepropagation modelinghasbeenperformed forthisarea,andthelicenseehasconcluded thatafirewouldnotpropagate throughout theroom.WithrespecttoHFOevents,thesubmittal statesthattheotherexternaleventsdonotpresentasignificant risktotheplant.Thisconclusion hasbeenreachedwithoutperforming adetailedPRA,andnoHFOcoredamagefrequency isreportedfortheplant.Thehazard-specific conclusions oftheanalysisareasfollows:-Ufdff<<IfdgfdRIPI(SRP)criteria, orthehazardoccurrence frequency wasdemonstrated tobeacceptably low.Unit2designwasfoundtoconformtotheSRPcriteria, andassuch,itwasconcluded thathighwinds/tornadoes donotposeasignificant threattotheunit.R.IU'dfgdIURRgtGuide(R.G.)1.59andSRPcriteria, andassuch,itwasconcluded thatexternalfloodsposenosignificant riskofasevereaccident.

-TheSt.LucieUnits1and2designsweredetermined toconformtoSRPcriteria, andassuch,itwasconcluded thattransportation andnearbyfacilityaccidents posenosignificant riskofasevereaccident.

Lucie,andtheimpactoflightning onplantriskisboundedbytheinternaleventsanalysis.

Nopotential vulnerabilities withrespecttoanyHFOeventwereidentified.

GenericIssuesandUnresolved SafetyIssuesForseismicevents,USIA45("ShutdownDecayHeatRemovalRequirements"

)isapplicable toSt.LucieNuclearPlant,butwasnotaddressed directlyinthelicensee's IPEEEsubmittal report.Thesite-specific seismicadequacyevaluation studiesperformed forSt.Lucie-1andSt.Lucie-2considered asuccesspaththatdependsonseismiccapability nftheauxiliary feedwater (AFW)system;seismiccapability ofotherdecayheatremovalsystems(feedandbleedcooling,andresidualheatremoval)weren'otspecifically addressed.

Thecondensate storagetank(CST)wastheonlycomponent oftheAFWsystemthatwasactuallyincludedintheseismicevaluation; thesubminalnotesthatAFWpumpswerepreviously reviewedEnergyResearch, Inc.vniERI/NRC95-504 forseismicadequacyaspartofGL81-14.InresponsetoanRAIissuedbytheNRCaspartoftheUSIAWreviewprocess,thelicenseehasindicated thattherealsoexistsaseismically qualified pathforfeed-and-bleed coolingattheplant.AspartofthefireIPEEE,thelicenseehasaddressed bothSandiafireriskscopingstudyissuesandUSIA45issues.Forbothcases,thelicenseehasdealtwiththeissuesanddoesnotidentifyanyoutstanding problemareas.However,thepossibility ofanearthquake causingafirewasnotaddressed.

ForareaswithThermo-lag, thelicenseehascheckedwhethertheprotection intendedbyThermo-lag isnecessary toreducethefireCDFbelow10~/ry.Forsom'ecompartments, ithasbeenconcluded thatevenwithoutthepresenceofThermo-lag, theCDFcanbebelow10~/ry.WithrespecttoHFOevents,thesubmittal doesnotdescribeanyformalanalysisofothersafetyissues.Eventhoughadirectdiscussion ofGenericIssue(GI)-103, "DesignforProbableMaximumPrecipitation PMP),"wasnotprovidedinthesubmittal, FPLnotedthattherearenoconcernsassociated withthesitewoodinglevelsandroofpondingthatcouldaccompany increased (beyonddesignbasis)PMPlevels.Someinformation isalsoprovidedintheSt.LucieIPEEEsubmittal whichpertainstogenericsafetyissue(GSI)-147, GSI-148andGS1-172.Vulnerabilities andPlantImprovements Thelicenseemakesageneralconclusion intheIPEEEsubmittal thattherearenovulnerabilities tosevereaccidentriskfromexternalinitiators.

However,safetyenhancements relatedtospecificexternalinitiators havebeenidentified andproposedforresolution.

Forseismicevents,theplant-specific seismicadequacyevaluations forSt.LucieNuclearPlant,Units1and2,haverevealedanumberofnoteworthy seismicfindings, including someidentified seismicoutliers, andhaveproposedrelevantplantimprovements asneeded.Thenotedconditions aresummarized below:St.LucieUnitI:Duringthewalkdowns, fiveanchorages andthebracingofthecomponent coolingwatersurgetankplatformwereidentified asconcernsbytheSRT.Inadditiontothesefiveanchorage

concerns, sixadditional anchorage concernswereidentified byFPLforsimilarcomponents indifferent equipment trains.Plantimprovements wereproposedtodisposeoftheseconcerns.

Threeseismicinteraction concernswereobservedanddocumented, asweresomecasesofpoorseismichousekeeping.

InresponsetotheNRC'sUSIA<6reviewprocess,thelicenseeisimplementing aprogramofstrictseismichousekeeping.

~Sr.LucieUnit2:Twoseismicinteraction concernswereobservedanddocumented.

Bothoftheseissueswereultimately evaluated andresolved.

Aconcernwasalsonotedpertaining towhetherornotthemountingofsomeinternalcoilsinanenergized transformer wasseismically adequate.

Thisconcern.was investigated duringanoutage,anditwasfoundthatthemountingwasadequate.

EnergyResearch, Inc.ixERI/NRC95-504 J~~I1r Itwasalsostatedintheseismicevaluation thatawalkdownofwalltransformers neededtobeperformed, todetermine whetherornotthesetransformers wouldneedtobesecured.Forfireevents,eventhoughthelicenseehasconcluded thattherearenofirevulnerabilities; nevertheless, ithasidentified severalcorrective actionstoimprovefiresafetyattheplant.Thecorrective actionsinclude:Ananalysisofusingthecross-tie betweenthetwounitstofurtherincreasetheavailability ofpowertotheaffectedunitundercertainfirescenarios, andarevisionoftheprocedures basedontheresultsofthisanalysis.

Revisethecurrentfireprotection procedures toensurethataroll-updoorbetweennon-safety switchgears iskeptclosedatalltimes.Ananalysisoffirescenarios inthe"B"switchgear roomtoreducetheCDFcontribution forthisareatobelow10~/ry,andarevisionoftheprocedures basedontheresultsofthisanalysis.

WithrespecttoHFOevents,allpotential hazardsweredismissed asnon-significant riskcontributors, withoutperforming adetailedPRA,andnovulnerabilities tosevereaccidents wereidentified.

Observations IntheseismicIPEEE,thesite-specific programfors'eismicadequacyevaluations ofSt.LucieUnits1and2addresses onlyasubsetoftheelementsspecified inNUREG-1407 asrecommended itemsthatshouldbeconsidered intheseismicIPEEEofareduced-scope plant.Theevaluations do,nonetheless, addresssomemeaningful IPEEE-related

concerns, andhaveresultedinasmallnumberofplantseismicsafetyenhancements.

GiventheNRC'sresolution ofrelatedUSIAA6concernsforSt.Lucie-l,thefollowing areconsidered tobethemostsignificant remaining weaknesses oftheseismicIPEEEsubmittal:

1.TheSSELisdeficient; r2.Aseismiccontainment performance assessment wasnotconducted; 3.Thetreatment ofhumanactionsisdeficient; 4.Thesubmittal doesnotprovideadequatedocumentation ofseismic-fire/flood interaction

concerns, including component-specific walkdownfindings;

'.TheseismicIPEEEisincomplete withrespecttoreduced-scope evaluation recommendations foundinNUREG-1407; and6.TheseismicIPEEEsubmittal isnotdocumented inaccordance withtheformatrecommended inNUREG-1407, AppendixC.InthefireIPEEE,thelicenseehasexpendedaconsiderable effortinthepreparation ofthefireanalysis, andhaspresented itinasummaryforminitsIPEEEsubmittal.

TheIPEEEreportcomplieswiththeconditions setforthinNUREG-1407.

Thelicenseehasemployedapropermethodology anddatabaseforEnergyResearch, Inc.ERI/NRC95-504 yl conducting thefireanalysis.

Basedonthedatapresented, notwithstanding someoftheweaknesses ofthesubmittal, itcanbeconcluded thatthelicenseehasconducted areasonable analysis.

Theoverallresultsarewithintherangeofconclusions reachedinotherpressurized waterreactor(PWR)fireriskstudies.WithrespecttoHFOevents,thesubmittal reliesmostlyonqualitative reasoning toscreenoutallsuchevents.Ingeneral,theanalysesareadequately supported, andfollowacceptedpracticeandtheoverallNUREG-1407 guidelines.

Insomecases,however,engineering judgments aremadewithoutsubstantiation.

Themostimportant casesthatrequireadditional supportareintheareaofhighwindsandtornadoes, particularly withrespecttohazardtoUnit1structures.

EnergyResearch, Inc.XiERI/NRC95-504 PREFACETheEnergyResearch, Inc.,teammembersresponsible forthepresentIPEEEreviewdocumented herein,include:htnhR.T.SewellM.Kazarians A;MoslehM.Khatib-Rahbar, Principal Investigator, ReportReviewA.S.Kuritzky, IPEEEReviewCoordination andIntegration R.T.Sewell,ReportIntegration Dr.JohnLambright, ofLambright Technical Associates, contributed tothepreparation ofSection2.4following thecompletion ofthedraftversionofthisTER.Thisworkwasperformed undertheauspicesoftheUnitedStatesNuclearRegulatory Commission, OfficeofNuclearRegulatory Research.

Thecontinued technical guidanceandsupportofvariousNRCstaffisacknowledged.

EnergyResearch, Inc.xnERI/NRC95-504 ABBREVIATIONS AFWCCWCDFCECFRCSTDBEDCEPRIERIFCIAFECRFIVEFPLFRSSFSARGlGIPGLGSIHCLPFHFOHVACICWIPE'PEEEIRSLLNLLOCALOSPMCCMFWMLWNRCOLPGAPMHPMPPMSPORVPRAPWRRABRAIAuxiliary Feedwater Component CoolingWaterCoreDamageFrequency Combustion Engineering CodeofFederalRegulations Condensate StorageTankDesignBasisEarthquake DirectCurrentElectricPowerResearchInstitute EnergyResearch, Inc.FireCompartment Interaction AnalysisFloridaEastCoastRailwayFireInducedVulnerability Evaluation MethodFloridaPowerandLightCompany.FireRiskScopingStudyFinalSafetyAnalysisReportGenericIssueGenericImplementation Procedure (SQUG)-GenericLetterGenericSafetyIssueHighConfidence ofLowProbability ofFailure(Capacity)

HighWinds,FloodsandOtherExternalInitiators Heating,Ventilation andAirConditioning IntakeCoolingWaterIndividual PlantExamination Individual PlantExamination ofExternalEventsIn-Structure ResponseSpectrumLawrenceLivermore NationalLaboratory LossofCoolantAccidentLossofOffsitePowerMotorControlCenterMainFeedwater MeanLowWaterNuclearRegulatory Commission Operating LicensePeakGroundAcceleration ProbableMaximumHurricane ProbableMaximumPrecipitation ProbableMaximumSurgePower-Operated ReliefValveProbabilistic RiskAssessment Pressurized WaterReactorReactorAuxiliary BuildingRequestforAdditional Information EnergyResearch, Inc.xiiiERI/NRC95-504 RCPRCSRLESERSISMASMMSNLSQUGSRPSRTSSESSELSSRAPSt.Lucie-1St.Lucie-2TERUSIReactorCoolantPump'ReactorCoolantSystemReviewLevelEarthquake StaffEvaluation ReportSafetyInjection SeismicMarginAssessment SeismicMarginMethodology SandiaNationalLaboratories SeismicQualification UtilityGroupStandardReviewPlanSeismicReviewTeamSafeShutdownEarthquake SafeShutdownEquipment ListSeniorSeismicReviewandAdvisoryPanelSt.LucieNuclearPlant,UnitISt.LucieNuclearPlant,Unit2Technical Evaluation ReportUnresolved SafetyIssueEnergyResearch, Inc.x]vERI/NRC95-504

004, (5I~~~1INTRODUCTION Thistechnical evaluation report(TER)documents theresultsofthe"submittalwnly" reviewoftheindividual plantexamination ofexternalevents(IPEEE)fortheSt.LucieNuclearPlant,Units1and2[1].Thistechnical evaluation review,conducted byEnergyResearch, Inc.(ERI),hasconsidered variousexternalinitiators, including seismicevents;fires;andhighwinds,floods,andother(HFO)externalevents.TheU.S.NuclearRegulatory Commission (NRC)objective forthisreviewistodetermine theextenttowhichtheIPEEEprocessusedbythelicensee, FloridaPowerandLight(FPL),meetstheintentofGenericLetter(GL)88-20,Supplement No.4[2].InsightsgainedfromtheERIreviewoftheIPEEEsubmittal areintendedtoprovideareliableperspective thatassistsinmakingsuchadetermination.

Thisreviewinvolvesaqualitative evaluation ofthelicensee's IPEEEsubmittal, development ofrequestsforadditional information (RAIs),evaluation ofthelicenseeresponses totheseRAIs,andfinalization ofthisTER.Theemphasisofthisreviewisondescribing thestrengths andweaknesses oftheIPEEEsubmittal,

'articularly inreference totheguidelines established inNUREG-1407

[3].Numerical resultsareverifiedforreasonableness, notforaccuracy; however,whenencountered, numerical inconsistencies arereported.

ThisTERcomplieswiththerequirements ofNRC'scontractor taskorderforanIPEEEsubmittal-only review.Theremainder ofthissectionoftheTERdescribes theplantconfiguration andpresentsanoverviewofthelicensee's IPEEEprocessandinsights, aswellasthereviewprocessemployedforevaluation oftheseismic,fire,andHFO-events sectionsoftheSt.LucieIPEEE.Sections2.1to2.3ofthisreportpresent.ERI'sfindingsrelatedtotheseismic,fire,andHFOreviews,respectively.

Sections3.1to3.3summarize ERI'sconclusions andrecommendations fromtheseismic,fire,andHFOreviews,respectively.

Section4summarizes theIPEEEinsights, improvements, andlicenseecommitments.

Section5includescompleted IPEEEdatasummaryandentrysheets.Finally,Section6providesalistofreferences.

St.LucieNuclearPlantisatwo-unitnuclearpowerfacilitylocatedonHutchinson Island,abouthalfwaybetweenthetownsofFt.PierceandStuart,ontheeastern(Atlantic) coastofpeninsular Florida.EachoftheSt.Lucieunitsisatwo-loopCombustion Engineering (CE)pressurized waterreactor(PWR),witharatedfull-power corethermaloutputof2,700MWtandanetelectrical outputof890MWe.Thecontainment foreachunitconsistsofasteelvesselsurrounded byareinforced-concrete biological shieldbuilding; anannularspaceexistsbetweenthesteelvesselandtheshieldbuilding.

St.LucieUnit1wentintocommercial operation duringDecember1976,andSt.LucieUnit2begancommercial operation duringAugust1983.Thetwounitsdonotphysically shareanymajorcommonareas.Eachunithasitsownturbinebuilding,

~reactorauxiliary building(RAB),andcontainment building.

Thereisonecontrolroomandonecablespreadingroomperunit.

Thesetworoomsaresituatedat theupperelevations oftheRAB.

Theauxiliary shutdownpanelsarelocatedinthe"B"switchgear room.Fromasystemsstandpoint,thetwounitsdonotshareanymajorfunctional-related

elements, exceptforoffsitepowerfacilities, across-tie forelectrical power,andatechnical supportcenterwhichislocatednextEnergyResearch, IncERI/NRC95-504 totheUnit1controlroom.Eachunithastwodieselgenerators, anauxiliary feedwater (AFW)system,twomotordriven mainfeedwater (MFW)pumps,highandlowpressuresafetyinjection (SI)systems,acomponent coolingwater(CCW)system,andanintakecoolingwater(ICW)system.BothCCWandICWsystemsareneededtopreventreactorcoolantpump(RCP)sealfailure.TheAFWsystemincludestwomotordriven pumps,aswell.asonesteam4riven pumpthatneedsdirectcurrent(DC)powertostart,andcanbeoperatedinamanualmode.Thedesignbasisearthquake (DBE)peakgro'undacceleration (PGA)forSt.LucieNuclearPlantis0.1g(horizontal andvertical) forthesafeshutdownearthquake (SSE).TheDBEspectralshapesaredifferent forthetwounits;Unit1wasdesignedforaHousnerspectralshape,andUnit2wasdesignedforaRegulatory Guide(R.G.)1.60spectralshape.CategoryIstructures forbothunitsarefoundedonCategory-I fill,underlain bycementedsandsandsandylimestones.

FortheIPEEEstudy,acutoffdateofDecember1993wasusedforestablishing plantconfiguration andoperating conditions.

1.2.1SeismicAsdocumented inNUREG-1407, forseismicIPEEEpurposes, St.Lucieisbinnedintothereduced-scope evaluation category.

Ratherthanimplementing areduced-scope seismicevaluation, FPLhaspursuedtheuseofasite-specific programforconducting theseismicIPEEEofSt.LucieNuclearPlant.Thissite-specificprogramwasdeveloped primarily fortreatment ofUnresolved SafetyIssue(USI)A%6,andrepresents a"scaled-back" approachtoachieving theobjectives ofGL8742[4].Thejustifications citedbyFPLforperforming ascaled-back analysisinclude:(a)verylowprobability ofhavinganearthquake attheSSElevelatFPL'splants;and(b)verylowvaluesofpotential offsitereleasesandpotential riskreductions giventhepostulated accidentscenarios andseismichazards.FPL'sscaled-back site-specific seismicadequacyprogramwasapproved, inconcept,bytheNRCforthepurposeofaddressing USIA46.However,onceFPLsubmitted theactualseismicadequacyevaluation study[5],theNRCidentified anumberofconcernsandpotential deficiencies withtheapproach.

TheNRC'sconcernsaredocumented initsstaffevaluation report(SER)pertaining toUSIA-46resolution

[6].Asiteinvestigation bytheNRCwasheldatFPL'scorporate headquarters andattheTurkeyPointNuclearPlantduringtheweekofDecember4-8,1995tohelpresolvetheconcernsnotedintheNRC'sSER.ManyoftheNRCconcernswerealleviated bywayofdiscussions withthelicenseeanditsconsultants; forotherconcerns, thelicenseehasagreedtoimplement corrective actionsidentified bytheNRC.Theseitemsaredocumented inanNRCsupplemental safetyevaluation report(SSER)[7],whereintheNRCstatesthatclosurehasbeenreachedonalloftheSERopenitemsforbothTurkeyPointandSt.Lucie.WithrespecttotheseismicIPEEE,theNRChadconcernswiththeuseoftheFPLsite-specific approachasabasisforresolving severeaccidentvulnerability issues.TheNRCnevergaveitsapprovalofFPL'sprogramfortreatment oftheseismicIPEEE.Nonetheless, FPLproceeded withuseofthesite-specific seismicadequacyevaluations forUSIA<6asthebasisforconducting theseismicIPEEE.Sincethelicensee's seismicIPEEEisessentially identical toitsUSIAA6seismicadequacyevaluation study,andbecausemanyoftherecommendations outlinedinNUREG-1407 forareduced-scope IPEEEEnergyResearch, Inc.ERI/NRC95-504 lj1 areachievedifanacceptable USIAA6evaluation hasbeenperformed, theNRC'sSERandSSERdetermines (toasignificant degree)thatacorresponding reviewconclusion bemadeforsimilarIPEEEconcerns.

Hence,thisTERindicates whereareviewfindinghas'beenbasedonNRC'ssafetyevaluation forUSIA46.Itisimportant topointoutthatonlySt.Lucie-1isaUSIA46plant.Thedesignbasisandseismicqualification employedforSt.Lucie-2aresimilartocurrentNRClicensing requirements.

Therefore, aseismicadequacyevaluation wasnotrequiredforSt.Lucie-2aspartofUSIA46resolution.

Still,FPLundertook suchanevaluation foraddressing theseismicIPEEE.FPL'sapproachtoseismicevaluation reliesprimarily onplantwalkdowns andontheuseofseismicreviewteam(SRT)judgment, supplemented withcalculations, asneeded,forresolving outliers.

Thewalkdowns haveaddressed thefollowing items:equipment seismiccapacityversusdemand,equipment construction

adequacy, anchorage

adequacy, seismicspatialinteraction

concerns, andseismichousekeeping concerns.

ThemainoverallelementsofFPL'ssite-specific seismicadequacyevaluation include:ProjectplanningSelection oftheseismicreviewteamPreparatory workpriortowalkdownSeismiccapability walkdowns Limitedseismicmarginassessment (SMA)calculation workResolution ofoutliersPeerreviewDocumentation FPL'sapproachtotheseaspectsoftheseismicIPEEEprocessforSt.LucieNuclearPlantisdiscussed inSection2.1.FPLfoundnoseismicvulnerabilities topotential severeaccidents, butdidreportasmallnumberofoutlierstoberesolved.

Additionally, inresponsetotheNRC'sUSIA46reviewprocess,FPLagreedtoresolveanadditional concernrelatedtoseismichousekeeping procedures.

1.2.2FireOverall,thelicenseehasconcluded thattherearenosignificant firevulnerabilities atSt.Lucie.Withtheexception ofthecontrolroom,cablespreading roomandthe"B"Switchgear room,allfirezonesandareaswerescreenedoutbasedona10perreactor-year (ry)coredamagefrequency (CDF)criterion.

Thelicenseecitesseveralconservative assumptions infireoccurrence rateandfireseverityforthecontrolroomandcablespreading room,andconcludes thatthesetwoareasdonotposeavulnerability.

Firepropagation modelinghasbeenperformed forthe"B"switchgear roomtoverifythatthisareadoesnotneedtobeconsidered asavulnerability.

Thelicenseehasaddressed theSandiafireriskscopingstudy(FRSS)issuesandUSIA<5concerns.

Forbothcases,thelicenseehasdealtwiththeissuesanddidnotidentifyanyoutstanding problemareas.However,thepossibility ofanearthquake leadingtoafirewasnotaddressed.

EnergyResearch, Inc.ERI/NRC95-504 ForareaswithThermo-lag, thelicenseehascheckedwhethertheprotection intendedbyThermo-lag isnecessary toreducethefireCDFtobelow10~/ry.Forsomecompartments, ithasbeenconcluded thatevenwithoutthepresenceofThermo-lag, theCDFisbelow10/ry.1.2.3HFOEventsThegeneralmethodology utilizedinthestudyconformstothatpresented inNUREG-1407 fortheanalysisofotherexternalevents.Itconsistsofthefollowing steps:1.Reviewofplant-specific hazarddataandlicensing bases.2.Determination ofconformance oftheplantrisksignificant structures tothe1975StandardReviewPlan(SRP)[8]criteria.

3.Screening ofplantstructures that'meet theSRPcriteriaforaspecifichazard.4.Determination ofthehazardfrequency forthosestructures thatdonotmeettheSRPcriteria.

5.Performing aboundinganalysisifthehazardfrequency calculated inStep4isfoundtobehigh.6.Performaprobabilistic riskassessment (PRA),ifnecessary.

Thelicenseehasperformed adetailedanalysisofthehighwinds,externalflooding, andtransportation andnearbyfacilityaccidenthazards.Additionally, thepotential forexternaleventshasalsobeenevaluated toensurethethattherearenohazardsuniquetotheplant.Theobjectives forthisassessment areconsistent withthoseofGL88-20,Supplement 4[2].FPLpersonnel havebeendirectlyinvolvedinallaspectsofthedevelopment, quantification, anddocumentation oftheanalysis.

Themajorfindingoftheanalysisisthattherearenovulnerabilities tosevereaccidentriskfromHFOevents.Initsqualitative reviewoftheSt.LucieIPEEE,ERIfocusedonthestudy'scompleteness inreference toNUREG-1407 guidance; itsabilitytoachievetheintentandobjectives ofGL88-20,Supplement No.4;itsstrengths andweaknesses withrespecttothestaff-the-art; andtherobustness ofitsconclusions.

Thisreviewdidnotemphasize confirmation ofnumerical accuracyofsubmittal results;however,anynumerical errorsthatwereobvioustothereviewers arenotedinthereviewfindings.

Thereviewprocessincludedthefollowing majoractivities:

Completely examinetheIPEEEsubmittal andrelateddocuments Developapreliminary TERandRAIsExamineresponses totheRAIsFinalizethisTERanditsfindingsBecausetheseactivities wereperformed inthecontextofasubmittal-only review,ERIdidnotperformasitevisitoranauditofeitherplantconfiguration ordetailedsupporting IPEEEanalysesanddata.EnergyResearch, Inc.ERI/NRC95-504 4g0 Consequently, itisimportant tonotethattheERIreviewteamdidnotverifywhetherornotthedatapresented intheIPEEEmatchestheactualconditions attheplant,andwhetherornottheprogramsorprocedures described bythelicenseehaveindeedbeenimplemented atSt.Lucie.1.3.1SeismicInconducting theseismicreview,ERIgenerally followedtheemphasisandguidelines described inthereport,Individual PlantExaminanon ofExternalEvents:ReviewGuidance[9],forreviewofaseismicmarginassessment, andtheguidanceprovidedintheNRCreport,IPEEEStepIReviewGuidanceDocument[10].Inaddition, onthebasisoftheSt.LucieIPEEEsubmittal, ERIcompleted dataentrytablesdeveloped intheLawrenceLivermore NationalLaboratory (LLNL)documententitled"IPEEEDatabaseDataEntrySheetPackage"[11].InitsSt.LucieIPEEEseismicreview,ERIexaminedthefollowing documents:

Sections1,2,3,4.8,6,7,and8oftheIPEEEsubmittal

[1]~TheUSIA<6seismicadequacyevaluation ofSt.LucieUnit1[5]~Theseismicadequacyevaluation studyofSt.LucieUnit2[12]~Section3.7.7oftheindividual plantexamination (IPE)submittal forSt.LucieUnits1and2[13]~TheNRC'sSER[6]andsupplemental SER(SSER)[7]oftheUSIA-46submittals forTurkeyPoint,Units3and4,andSt.LucieUnit1~Thelicensee's response[14]totheRAIsgenerated aspartoftheinitialsubmittal reviewTheIPEEEsubmittal

[1]itselfcontainsonlyonepageofdiscussion relatedtoseismicevaluation.

Consideration oftheseismicadequacyevaluation studies(References

[5,12])andtheNRC'sevaluation

[6,7]ofthelicensee's USIA-46submittal constituted themostsignificant elementofthepresentseismicreview.Thechecklist ofitemsidentified inReference

[9]wasgenerally consulted inconducting theseismicreview.Someoftheprimaryconsiderations intheseismicreviewhaveincluded(amongothers)thefollowing items:Wereappropriate walkdownprocedures implemented, andwasthewalkdowneffortsufficient toaccomplish theobjectives oftheseismicIPEEE?Wasthedevelopment ofsuccesspathsperformed inamannerconsistent toprescribed practices?

Wererandomandhumanfailuresproperlyconsidered insuchdevelopment?

Werecomponent demandsassessedinanappropriate manner,usingvalidseismicmotioninputandstructural responsemodeling, asapplicable?

Wasscreening appropriately conducted?

Werecapacitycalculations performed forameaningful setofcomponents, andarethecapacityresultsreasonable?

Doesthesubmittal's discussion ofqualitative assessments (e.g.,containment performance

analysis, seismic-fire evaluation) reflectreasonable engineering

judgment, andhaveallrelevantconcernsbeenaddressed?

EnergyResearch, Inc.ERI/NRC95-504

~HastheseismicIPEEEproducedmeaningful

findings, hasthelicenseeproposedvalidplantimprovements, andhaveallseismicriskoutliersbeenaddressed?

Itisimportant tonotethat,inanumberofinstances, IPEEEreviewfindingshavebeenreportedonthebasisofconsistency withrelatedfindingsinNRC'sSER[6]andSSER[7]forUSIA46,ratherthanonthebasisofaseparatereviewforIPEEE.1.3.2FireDuringthistechnical evaluation, ERIreviewedthefire-events portionoftheIPEEEforcompleteness andconsistency withpastexperience.

Thisreviewwasbasedonconsideration ofSections1,2,4,6,7and8ofReference

[1],andSectionIIofReference

[14].Inaddition, asetoflayoutdrawings[15,16]pertaining tofireprotection wereavailable forreview.TheguidanceprovidedinReferences

[9,10]wasusedtoformulate thereviewprocessandorganization ofthisdocument.

ThedataentrysheetsusedinSection5hav'ebeencompleted inaccordance withReference fl1].Theprocessimplemented forERI'sreviewofthefireIPEEEincludedanexamination ofthelicensee's methodology, data,andresults.ERIreviewedthemethodology forconsistency'with currently acceptedandstate-of-the-art methods.ThedataelementofafireIPEEEincludes, amongothers,suchitemsas:CableroutingFirezone/area partitioning Fireoccurrence frequencies Eventsequences Firedetection andsuppression capabilities Forafewfirezones/areas thatweredeemedimportant, ERIalsoverifiedthelogicaldevelopment ofthescreening justifications/arguments (especially inthecaseoffire-zone screening) andthecomputations forfireoccurrence frequencies andCDFs.Ratherthanperformacompletely independent setofcalculations, however,thereviewteamuseditsexperience andcomparisons ofotherplantsandfireevaluation results,inordertojudgetheaccuracyandcompleteness oftheinformation providedbythelicensee.

Specialattention wasdirectedto:(1)thescreening methodology, becauseatrendtoprematurely screenoutpotentially significant areasortoinadequately justifyscreening outanarea,hasemergedasacommonproblemamongpastfirePRAsandIPEEEanalyses; and(2)thelicensee's assumptions, becausetheresults'fmanystudiesareundulyinfluenced byassumptions madetosimplifyorintroduce conservatisms.

1.3.3HFOEventsThereviewprocessforHFOeventscloselyfollowedtheguidanceprovidedinthereportentitledIPEEEStepIReviewGuidanceDocument[10].Thisprocessinvolvedexaminations ofthemethodology, thedataused,andtheresultsandconclusions derivedinthesubmittal.

Sections1,2,5,6,7and8oftheIPEEEsubmittal

[1],andlicenseeresponses toRAIs[14],wereexaminedinthisHFO-events review.TheIPEEEmethodology wasreviewedforconsistency withcurrently acceptedpractices andNRCrecommended procedures.

Specialattention wasfocusedonevaluating theadequacy"ofdatausedtoestimatethefrequency ofHFOevents,'andonconfirming thatanyanalysisofSRPconformance wasappropriately executed.

Inaddition, thevalidityofthelicensee's conclusions, inconsideration oftheresultsreportedintheIPEEEsubmittal, wasassessed.

Also,bounding-analysis andPRAresultspertaining tofrequencies EnergyResearch, Inc.ERI/NRC95-504 Pr' ofoccurrence ofhazardsandestimates ofconditional probabilities offailure,werecheckedforreasonableness.

Reviewteamexperience wasreliedupontoassessthevalidityofthelicensee's evaluation.

EnergyResearch, Inc.ERI/NRC95-504 2CONTRACTOR REVIEWFINDINGS2.15gismzAsummaryofthelicensee's seismicIPEEEprocesshasbeendescribed inSection1.2.Here,thelicensee's seismicevaluation isexaminedindetail,anddiscussion isprovidedregarding significant observations encountered inthepresentreview.2.1.1OverviewandRelevance oftheSeismicIPEEEProcessa.SeismicReviewCaregoryandRevie-Level Eanhquake (RLE)St.LucieNuclearPlantislocatedinanareaoflowseismicity, ontheeasterncoastofpeninsular Florida.EachofthetwoSt.Lucieunitsisatwo-loopCombustion Engineering PWR.St.LucieUnit1wentintocommercial operation duringDecember1976,andisintheseismicqualification utilitygroup(SQUG)/USI A46program;St.LucieUnit2begancommercial operation duringAugust1983,andisnotintheUSIAP6program.Thedesignbasisearthquake (DBE)peakgroundacceleration (PGA)forSt.LucieNuclearPlantisO.lg(horizontal andvertical) forthesafeshutdownearthquake (SSE).TheDBEspectralshapesaredifferent forthetwounits;Unit1wasdesignedforaHousnerspectralshape,andUnit2wasdesignedfora,Regulatory Guide(R.G.)1.60spectralshape.CategoryIstructures forbothunitsarefoundedonCategory-I fill,underlain bycementedsandsandsandylimestones.

Duetothelowseismichazardatthesite,St.Luciehasbeendesignated asareduced-scope plantinNUREG-1407.

TheRLEisequivalent totheSSE.b.SeismicIPEEEProcessThelicenseehasimplemented asite-specific seismicadequacyevaluation programbasedonamethodology ithascompiledforexecuting itsUSIA-46resolution programatTurkeyPointUnits3and4,andatSt.LucieUnit1.(TheNRChasdetermined, pendingapprcpriate follow-up actionbythelicensee, thatUSIAMhasbeenadequately resolvedforSt.Lucie-1andTurkeyPoint[6,7].)ThelicenseeclaimsthatitsprocessconformswiththeOptionalMethodology ofParagraph 3.3inNUREG-1407.

However,theprogramwasneveractuallyapprovedbytheNRC.c.ReviewFindingsTheIPEEEprocessisnotfullyconsistent withtherecommended guidelines ofNUREG-1407 forSt.Lucie.FPL'sseismicprogramsforSt.LucieUnits1and2addressonlyaportionoftheseismicIPEEEelements/concerns forareduced-scope plant.TheIPEEEsubmittal forSt.LucieUnit1isessentially identical totheUSIAMsubmittal.

Hence,theconcerns/findings documented bytheNRCforUSIA<6areapplicable toanumberoftheaspectsoftheseismicIPEEE.Nonetheless, thefactthatFPL'sseismicadequacyevaluation programdepartsfromacompletereduced-scopeassessment isviewedtobeasignificant weakness.

TheoverallseismicIPEEEmethodology EnergyResearch, Inc.ERI/NRC95-504 jr 4employedbyFPLhasonlyalimitedpotential toachieveIPEEEobjectives, andtoassesssevereaccidentvulnerabilities atSt.LucieNuclearPlant.2.1.2SuccessPathsandComponent ListSuccesswasdefined,forpurposesofidentifying asuccesspath,astheabilitytoachieveandmaintainahotshutdowncondition for8hours.Lossofoffsitepowerwasassumedinchoosingthesuccesspath.Inaddition, adesignbasisearthquake wasassumednottotripthereactor.Theprimaryelementsofthechosensuccesspathinclude:supervisory andcontrolfunctionrequirements, requirements ofdecayheatremovalviatheAFWsystem,emergency electrical powerrequirements, chemicalandvolumecontrolrequirements, andequipment cooling(ultimate heatsink)requirements viatheCCWandICWsystems.Thesubmittal statesthatallactiveequipment pertaining tothesuccesspathwereidentified indeveloping asafeshutdownequipment list(SSEL).Somepassivecomponents, suchastanksandheatexchangers, werealsoincludedintheSSEL.Asignificant numberofcomponents (e.g.,AFWpumps)wereremovedfromtheSSELbecausetheyhadbeenpreviously reviewedforseismicadequacyinanotherprogram.(Similarly, potential interaction concernsthatinvolvedblockwallswereconsidered resolvedifthewallswerepreviously addressed underIE80-11[17]).Theresulting SSELdefinesthesetofcomponents considered inplantwalkdowns.

FPL'sseismicadequacyevaluation doesnotclearlyidentifythechosensuccesspath,nordoesitpresentasuccesspathlogicdiagram.Onlyonesuccesspathwasinvolvedindeveloping theSSEL,andonlyalimitedsetofcomponents wereidentified foreachmajorsuccess-path function.

Thestudydidnotexplicitly addressasmall-break lossofcoolantaccident(LOCA)inthedevelopment ofthesuccesspathandSSEL.TheSSELconsiders activecomponents andapartiallistofpassivecomponents.

Thesuccesscriterion usedintheFPLstudyistheabilitytoachieveandmaintainhotshutdownforatimeperiodofonly8hours,ratherthantherecommended 72hours.However,inresponsetoRAIsraisedbytheNRCinitsUSIAMreviewprocess,FPLindicated thattheplanthasmultiple(albeitnon-seismically qualified) watersourcesthatcouldprovidecoolingfor72hours.Inaddition, FPLindicated thattheplanthasthe(seismically qualified) capability o~indefinitely longfeed-and-bleed cooling.Thus,theequipment listdeveloped intheFPLstudyappearstobeconsiderably limited,andconsiders onlyasubsetofcomponents thatshouldbeevaluated inareduced-scope assessment.

2.1.3Non-Seismic FailuresandHumanActionsa.OverallApproach44Theseismicadequacystudiesnotethatareviewofoperating procedures wasperformed forSt.LucieNuclearPlanttoverifytheequipment listandtoidentifyanyequipment whichmightberequiredtobringthereactorfrom100%powertohotshutdown.

Additionally, operating procedures toshutdownthereactor,takethereactortohotshutdown, torespondtoreactortrip,andtorespondtolos-of'offsitepowerwerereviewed.

Nomentionismadeofspecificnon-seismic failuresorhumanactionsthatmightlimitthecapability ofthechosensuccesspath.EnergyResearch, Inc.ERI/NRC95-504 ly b.Screening CrireriaRandomandoperatorfailurerateswerenotreported; noscreening criteriawereappliedwithrespecttonon-seismic failuresandhumanactions.c.ReviewFindingsAccording toNUREG-1407, candidate successpathsshouldbescreenedtoinsurethatimpactsofnon-seismicfailuresandhumanactionswillnotbecontrolling factorsinhibiting thelikelihood ofsuccessful hotshutdown.

FPL'sseismicevaluation hasnotidentified thespecificrandomfailuresandhumanactionswhichmightcompromise theintegrity ofthechosensuccesspath.Hence,thelicensee's studyisinadequate initstreatment ofnon-seismic failuresandhumanactions,whichisthusviewedtobeaweaknessofthestudy.2.1.4SeismicInputSeismicinputsforevaluation studiesofSt.Lucie,Units1and2,weredefinedbySSEspectraandotherplant-specific design-basis commitments inthefinalsafetyanalysisreport(FSAR).ForSt.Lucie-l,theSSEisidentified byaHousnerspectralshapeanchoredtoaPGAlevelofO.lg.ForSt.Lucie-2,theSSEisaR.G.1.60[18)shape'anchored tothesamePGAvalue.NUREG-1407 indicates thattheSSEgroundresponsespectrashouldbeusedtodefineinputtostructures, andforcomputing in-structure responsespectra.FPL'sseismicadequacyevaluation programusestheSSEspectrumorFSARin-structure spectraasthebasisfordefiningseismicinputforcomponents.

Hence,thelicensee's definition anduseofseismicinputisconsistent withtheguidelines ofNUREG-1407 forareduced-scope plant.2.1.5Structural Responses andComponent DemandsSt.LucieUnit1hadexistingfloorresponsespectracurvesforthecontainment structure andtheauxiliary building; St.LucieUnit2hadexistingfloor'esponse spectracurvesforallsafety-related buildings andstructures.

Buildingmodelsusedtogeneratefloorresponsespectraincludedtranslational androtational springstoaccountforsoil-structure interaction effects.ThefloorresponsespectrawereusedtodefinedemandsformanyoftheSSELcomponents.

Forcomponents whereexistingfloorresponsespectrawerenotavailable forassessing demands(whichwasthecaseonlyforSt.LucieUnit1),estimates ofcomponent demandsweremadebaseddirectlyontheSSEspectrum.

Theapproachforassessing suchdemands(forequipment lessthan40feetabovegrade)wasto:(a)takethepeakspectralacceleration fromthe5%dampedSSEspectrum, (b)multiplythispeakvalueby1.5toaccountforbuildingamplification, and(c)multiplyagainbyafactorof1.25forconservatism.

NUREG-1407 indicates thatexistingFSARin-structure spectra,basedonSSEinputandFSARlicensing

criteria, maybeusedforevaluating component demands.IntheFPLseismicadequacystudies,FSARin-structure spectrawereused,whenavailable, toestablish equipment demands.Whenin-structure spectrawerenotavailable (St.LucieUnit1only),agenerally conservative procedure basedonscalingthepeakSSEspectralacceleration wasusedtodefinecomponent demands.Thelicensee's development ofcomponent demandsthusappearsconsistent, toasignificant degree,withtheguidelines ofNUREG-1407 EnergyResearch, Inc.10ERI/NRC95-504

'r0 forareduced-scope plant.Additionally, theNRChasacceptedthisaspectofthelicensee's analysisforUSIA46resolution

[7].2.1.6Screening CriteriaScreening fortheSt.Lucieseismicevaluation studieshasnotfollowedtheformalprocedures described inthegenericimplementation procedure (GIP)[19]orinElectricPowerResearchInstitute (EPRI)NP-6041[20],asrecommended inNUREG-1407.

Rather,theprocedures described inReference

[21],theSeniorSeismicReviewandAdvisoryPanel(SSRAP)document, havegenerally beenimplemented.

WhetherGIP,EPRINP-6041,orotherprocedures areusedforscreening, screening caveatsmustbeobserved, anchorage capacitychecksmustbeperformed, andspatialinteraction issuesmustbeappropriately assessed.

Additionally, inanyscreening procedure, SRTjudgmentplaysthemajorroleincomponent evaluations.

FPL'sscreening approachhasbeenbasedprimarily onSRTjudgment, oncomparisons ofestimated anchorage capacityversusSSE-consistent demand,andoninsightsderivedbytheSSRAP.Althoughthelicensee's approachtoscreening doesnotconformprecisely totherecommendations ofNUREG-1407 forareduced-scope plant,itisjudgedtobeareasonable processthatsubstantially achievesthesignificant intentofcomponent screening.

2.1.7PlantWalkdownProcessa.Preparatory 8'orkApre-walkdown oftheplantwasperformed tohelptheseismicreviewteam(SRT)membersidentifywhatinformation andassistance wouldbeneededduringtheseismiccapability walkdown.

FPLengineers gatheredgenericandequipment-specific documentation asdeemednecessary bytheSRT.Inaddition, FPLstafffamiliarwithplantsystemsdeveloped thelistofequipment tobewalkeddown.b.SeismicCapability WalkdownPlantwalkdowns wereconducted byanSRTconsisting ofthreehighlyexperienced walkdownexperts.Theseismicadequacyevaluation studieshavereliedheavilyonthejudgmentoftheseengineers.

Duringthewalkdown, FPLprovidedstaffengineers tohelpsupporttheSRTmembers,primarily inobtaining additional plantinformation thatwasneededonacase-by-case basis.Theactualdurationofseismicwalkdowns isnotmentioned inthedocumentation.

Fourconsiderations wereaddressed intheplantwalkdownscreening effort:(1)equipment seismiccapacityversusdemand,(2)construction adequacyofequipment, (3)anchorage

adequacy, and(4)seismicspatialinteraction concerns.

Thewalkdownalsomadenoteofconcernsrelatedto:(5)generalseismic"housekeeping" issues.Eachoftheseaspects.ofplantwalkdowns andcomponent screening isdescribed brieflybelow.-Thisscreening itempertainstoidentification ofseismicadequacyproblemsthatcouldbeinherenttospecifictypesofunqualified seismicequipment.

Theseencompass thetypesofproblemsthatwouldbefoundinaqualification test,EnergyResearch, Inc.ERI/NRC95-504 including:

functional

problems, internally fragileelements, andinadequate overallstructural resistance ofacabinet.TheSt.Lucieseismicadequacyevaluations treatedthisiteminagenericwaybasedonfindingsoftheSSRAP,asdocumented inReference

[21].Itwasdemonstrated intheevaluation studiesthat(forusewithrespecttoequipment havinganaturalfrequency greaterthan8Hzandlocatedlessthan40feetabovegrade)theSSRAPboundingspectrumenvelopes plantSSEspectraovertheentirefrequency range.Itwasalsodemonstrated that(forusewithrespecttoequipment havinganaturalfrequency lessthan8Hzorlocatedmorethan40feetabovegrade)theSSRAPboundingspectrummultiplied by1.5enveloped plantfloorresponsespectra.Sincetheboundingspectrumrepresents anexperience-based seismicruggedness threshold forunqualified nuclearpowerplantequipment, theFPLstudyconcludes thatseismiccapacityversusdemandwasjudgedacceptable forallplantcomponents.

Theplantwalkdowns, therefore, didnotgivemuchattention tothisscreening item,onacomponent-by-component basis.-Thisscreening itempertainstoidentification ofseismicadequacyproblemsthatcouldbeattributed totheconfiguration ormannerofconstruction/installation oftheequipment attheplant.Generally

speaking, theas-builtconfiguration ofequipment canbeconsidered

adequate, providedthatcertaincaveatshavebeenconsidered andsatisfied.

FPLreasonedthat,duetolowseismicity atFPLplantsites,specificcaveatsdidnotneedtobeaddressed foreachtypeofequipment.

Theseismicevaluation studyfurthernotedthatSRTmembersareexpertsintheareaofseismicadequacyofequipment, andthattheynotedanyequipment-specific detailsthattheyfeltwereseismically vulnerable.

I'lIIIIIIII'Ithatareduetonon-existent orweakanchorage.

Theconstructed anchorage configuration canbeconsidered asacaveattobeconsidered intheevaluation ofallcomponents.

Itisaspecialcaveat,however,becauseitstreatment usuallyrequiresmorethanjustavisualinspection; theexpecteddemandontheanchorage andanumerical estimateofanchorage capacityareoftenneededtosatisfyanchorage caveats.Intheseismicadequacyevaluations, SRTjudgmentwasusedtoscreenout"obviously rugged"anchorages.

Otherwise, anumerical estimateofseismicadequacyofanchorage components wasobtainedandcomparedagainstcomponent anchorage demand.Anyproblemsnotedwithanchorage capacityweredesignated aspotential outlierstoberesolved.

4.-Thisscreening itempertainstotheidentification ofphysicaleffectsthatcouldindependently compromise theperformance ofanotherwise well-installed seismically adequatecomponent.

Suchphysicaleffectsinclude:objectsimpacting equipment inanymanner,conduitpull-outduetoinadequate flexibility oflinesattachedtoequipment, blockwallcollapses, etc.Duringthewalkdowns, SRTmemberslookedfor,andmadenoteof(onwalkdownworksheets),anypotential seismicspatialinteraction concerns; identified concernsweredesignated aspotential outliers.

EnergyResearch, Inc.12ERI/NRC95-504

~gPI/

5,-Thiswalkdownitempertainstosituations that,althoughnotleadingtofailureofanimportant safety-related component, canexacerbate problemsand/orinhibitoperatoreffectiveness following anearthquake.

Anyinstances ofpoorseismichousekeeping observedbySRTmemberswerenotedandreportedtoFPL.Amongthesefivewalkdownitems,primaryconsideration wasgiventoassessing anchorage adequacyandtoidentifying seismicspatialinteractions.

c.ReviewFindingsNUREG-1407 recommends theuseofGIPorEPRINP-6041walkdownprocedures.

TheSt.Luciewalkdownhasimplemented procedures substantially similartothese,perhapsallowingforsomewhatgreaterlatitudeintheuseofexpertjudgment.

Dueinlargeparttotheexceptional qualifications oftheSRTmembers,andtheNRC'sacceptance oftheseismicwalkdownforUSIA<6resolution, thelicensee's walkdownprocessis'considered tobeadequateinidentifying outliersamongthosecomponents thathavebeenincludedinthescopeofwalkdowns.

2.1.8Evaluation ofOutliersa.OverallApproachTheseismicadequacyevaluations donotmakeacleardistinction between"outlier" and"potential outlier."

AllitemsnotscreenedoutbytheSRTwereaddressed insomemannerbyFPL.Forpotential anchorage outliers(i.e.,thoseanchorage concernsscreenedinbytheSRTduringplantwalkdowns),

more-detailed calculations wereperformed tobetterdetermine seismicadequacy.

Anycomponent havinginadequate/low anchorage capacitywasidentified asanoutlierrequiring resolution byFPL.b.HighConjfdence ofLowProbabiliry ofFailure(HCLPF)Calcularions ForSt.LucieUnit2,HCLPFcalculations wereperformed formanylarge,flat-bottom tanks.NoHCLPFcalcu]ations wereperformed forblockwallsidentified tobeapotential interaction problem.(Theseismicadequacyevaluations relyonearlierIE80-11calculations.)

c.ReviewFindingsForsomecomponents thatwerescreened-in atSt.LucieNuclearPlant,capacitycalculations wereperformed todemonstrate whetherornotthecomponent mettheFSARdemand(ortheconservative approximation totheFSARdemand).Forcomponents identified asfinaloutliers, however,theoutlierassessment wasoftenreadilymade(withoutcalculation) duetoanobviously deficient condition (e.g.,sealweldononesideof480VMotorControlCenter(MCC)1A6,missingweldsonMCCportionof480VLoadCenter1A3).Foreachfinaloutliernoted,FPLproposedacorrective measureandsubmitted non-conformance resolution documentation.

ERI/NRC95-504Thelicensee's walkdownprocessisjudgedtobeadequateinidentifying outliersamongthose(limitedsetof)components thathavebeenincludedinthescopeofwalkdowns.

EnergyResearch, Inc.13

2.1.9RelayChatterEvaluation NUREG-1407 indicates thatcompletion oftheUSIA46reviewrequirements forrelaychatterevaluation willsatisfytheIPEEEintentforreduced-scope plantsthatarealsoUSIA-46plants.Forreduced-scope plantsthatarenotalsoUSIA-46plants,norelaychatterevaluation isnecessary.

Thelicensee's IPEEEsubmittal doesnotmentionarelaychatterevaluation forSt.Lucie-1~However,duringNRC'sUSIA@6reviewforTurkeyPointandSt.Lucie-l,itwasrevealedthatFPLhadassessedbadactorrelays,verifiedmountings ofrelays,anddemonstrated thattherewerenodeleterious effectsofchatterofbadactorrelays.TheNRCacceptedthelicensee's relayevaluation forUSIA-46resolution, andhence,theNUREG-1407 recommendation fortheseismicIPEEEissatisfied forSt.Lucie-1.NUREG-1407 doesnotrequestarelayevaluation forSt.Lucie-2,anon-USIA-46plant.2.1.10SoilFailureAnalysisNUREG-1407 statesthatnoevaluation ofsoilfailuresisrequiredforareduced-scope plant.Correspondingly, thelicenseehasnotperformed suchananalysis.

2.1.11Containment Performance AnalysisForreduced-scope plants,NUREG-1407 requeststhatperformance ofcontainment andcontainment systemsshouldbeaddressed.

Components necessary toachievesuccessful accidentmitigation needtobeincludedinthescopeofseismicwalkdowns andoutlierevaluation.

FPLdidnotincludethecontainment structures orcontainment systemsinitsseismicadequacyevaluations ofSt.Lucie,Units1and2.Hence,thelicensee's seismicadequacystudiesofSt.LucieUnitIandSt.LucieUnit2arenotresponsive totheNUREG-1407 requestforacontainment performance analysis.

2.1.12Seismic-Fire Interaction andSeismically InducedFloodEvaluations a.Evaluarion ofSeismic-Fire Inreracrions Section4.8oftheIPEEEsubmittal reportdiscusses seismic-fire interactions.

Thetopicofseismic-fire interactions isoneelementoftheSandiafireriskscopingstudy(FRSS)issues.TheIPEEEsubmittal statesthatallSandiaFRSSissuesaremorethanadequately coveredthroughtheSt.LucieFireProtection Program.Intermsofdetailsoftheseismic-fire evaluation, however,thesubmittal indicates onlythat:"Essentially, theII/Icriteriawasappliedtofiresystemswhosefailurecouldaffectoperation ofsafety-relatedsystems."

Section2.2.12providesadditioncommentsonFPL'sseismic-fire evaluation forSt.Lucie.Nospecificdiscussions ofseismically inducedfires,ofseismicinadvertent actuation offiresuppression systems,orofseismically inducedfailureoffiresuppression systemswereprovidedinthesubmittal.

Seismic-Fire WalkdownThesubmittal doesnotindicatethataseismic-fire walkdownevaluation wasconducted.

EnergyResearch, Inc.14ERI/NRC95-504 c.Seismically InducedFloodEvatuarion Nodocumentation pertaining toevaluation ofseismically inducedfloodswassubmitted.

d.ReviewFindingsTheSt.Lucieseismicadequacyevaluation hasnotfullyaddressed seismic-fire interactions orseismically inducedfloods.2.1.13Treatment ofUSIA45Areduced-scope seismicassessment shouldconsidertheseismiccapability ofcomponents necessary forsuccessful decayheatremoval,inresponsetoUSIA<5(DecayHeatRemovalRequirements).

FPL'sseismicIPEEEsubmittal andseismicadequacyevaluation studiesforSt.LuciedidnotdirectlydocumentfindingsforanyGenericIssues(GIs)lUSIs otherthanUSIA-46(forSt.LucieUnit1).Indirectly, USIAQSwasaddressed owingtothefactthatthesuccesspathneededtoaccomplish onemethodofdecayheatremoval(i.e.,viatheAFWsystem).However,theAFWpumpswereeliminated fromtheseismicevaluation (becausetheyhadbeenpreviously examinedforseismicadequacyelsewhere),

andonlythecondensate storagetank(CST)wasidentified asanecessary component intheSSEL.Thelicensee's seismicadequacystudydoesnotaddressameaningful scopeofcomponents relatedtodecayheatremovalfunctions.

Thisweaknessstemsfromthefact(notedinSection2.1.2ofthisTER)thattheSSELisonlypartially complete.

2.1~14PeerReviewProcessAnindependent externalpeerreviewwasconducted byDr.PaulSmithfortheseismicadequacyevaluation studiesofSt.Lucie-1andSt.Lucie-2.Thispeerreviewidentified fiveadditional seismicconcerns.

FPLengineers alsoreviewedtheseismicstudies.Ameaningful peerreviewappearstohavebeenconducted forthelimited-scope seismicevaluation studiesofSt.Lucie-1andSt.Lucie-2.2.1.15SummaryEvaluation ofKeyInsightsOnlyasubsetofcomponents neededtoensuresuccessful shutdownareconsidered inFPL'sequipment list,andhence,theseismicIPEEEprocesshasonlyalimitedpotential torevealvulnerabilities oroutliers.

However,forthosecomponents thathavebeenincludedinthescopeofFPL'sseismicadequacyevaluation studies,theprocessimplemented forscreening

outliers, andforaddressing theirresolution, isconsidered tobeappropriate andadequate.

FPL'sseismicadequacyevaluation studyhasidentified anumberofoutliers(primarily relatingtoweakanchorage),

andhasproposedrelevantmodifications toenhancesafety.TheNRChasalreadyreviewedtheseoutliersandmodifications forSt.LucieUnit1,aspartofUSIA-46resolution.

Additionally, theNRChasconducted asiteinvestigation toidentifyanyvulnerabilities thatmayrequirefurtherEnergyResearch, Inc.ERI/NRC95-504 analysis/treatment.

Asaresult,FPLisperforming follow-up actionstoimplement astricthousekeeping programatSt.Lucie.NooutliersreportedbythelicenseeappeartorequirefurtheranalysisforseismicIPEEEpurposes.

However,additional outliersmayhavewellbeenfoundifthe'licensee hadexpandedthescopeofitsseismicadequacyevaluations toaddressIPEEEwnly components andissues.Furthermore, thelicenseeelectednottoconductacontainment performance analysisatSt.LucieNuclearPlant.Thus,novulnerabilities affecting containment performance, relatedtoseismicbehaviorofcontainment systems(e.g.,containment cooling,containment isolation, etc.),norpertaining todirectseismicfailureofthecontainment structures themselves, wereidentified.

TheSt.LucieNuclearPlantseismicadequacyevaluation studiesarecapableoffindingonlyalimitedsetofseismic-related, severeaccidentvulnerabilities.

2.2BzgAsummaryofthelicensee's fireIPEEEprocesshasbeendescribed inSection1.2.Here,thelicensee's fireevaluation isdescribed indetail,anddiscussion isprovidedregarding significant observations encou'ntered inthepresentreview.2.2.1OverviewandRelevance oftheFireIPEEEProcessa.MethodSelectedforFireIPEEEThefireanalysiswasperformed perfire-induced vulnerability evaluation (FIVE)methodology (Reference

[22])intwophases.Thefirstphasewasascreening stepbasedprimarily oncontentsofafirezoneorarea.Inthesecondphase,thefrequency ofcoredamagefromafireinaspecificfirezonewasestimated usingtheformulations anddataprovidedintheFIVEmethodology.

b.KeyAssumptions UsedinPerforming FireIPEEETheIPEEEdoesnotprovideaseparatelistofassumptions.

However,thepresentreviewhasidentified thefollowing assumptions whichcouldhaveasignificant impactonthefinalresults:Firebarriers/boundaries weretakentobeasgoodasrated.Nodiscussions areprovidedastowhetheractivesystems(forexampleaselfclosing/normally openfiredoor)arepartoffirebarrierdefinition.

Noconsideration isgiventothepossibility ofopendoors,openducts,failureoffiredampers,etc.Thisresultsincross-zone firesbeingjudgedtohavenegligible risk.Thermo-lag wasassumedtobeeffective foraselectgroupoffireareas.-.Allfiresinareascontaining safeshutdownequipment wereassumedtoleadtoreactortrip.Cont.inment fireswerenotanalyzedexplicitly.

Thisapproachwasbasedonthe'observation thatmostcontainment firesarerelatedtoRCPoilfires,whichhavebeenminimized withtheimprove-mentsintheoilcollection system.EnergyResearch; Inc.16ERI/NRC95-504

~Allremotelyoperatedvalveswithhand-wheels wereassumedtobeavailable formanualoperation.

c.StatusofAppendixRModijicanonsAppendixRmodifications wereassumedtobecompleted.

d.NeworExistingPRATheIPEEEisanewstudy.Itusestheresultsofthealreadycompleted IPE[13]andPRA[23]forSt.Lucie.2.2.2ReviewofPlantInformation andWalkdownWalkdownTeamComposition Different typesofwalkdowns havebeenconducted.

Thermo-lag evaluation walkdowns providedinformation forthosecompartments wherethisinsulating materialwaspresent.Forotherareas,walkdowns havebeenconducted specifically forIPEEEfireanalysis.

Inallcases,thewalkdownteamshaveincludedFPLengineers, fireprotection specialists, andpersonnel fromaconsulting firm.Thefollowing areashavebeenreviewed:

"A"and"B"safety-related switchgear "A"and"B"electrical penetration roomsThecablespreading roomsThe"A"cableloftareaReactorauxiliary buildingbasementhallwayandhallareasHeating,ventilation, andairconditioning (HVAC)equipment areaIntakecoolingpumpareasTurbinebuildings andrelatedareasAuxiliary feedwater pumpareasInverterroomBothunitshavebeenvisitedinthewalkdowns.

References

[1]and[14]donotprovideanydetailsonhowtheobservations ofthewalkdownhavebeenrecorded, andtheydonotprovidetheformatorasampleoftherecords.Thelicenseecitesotherinspections andthegeneralfamiliarity oftheIPEEEfireanalysisteamwiththeplantasadditional basisfortheIPEEEfireanalysis.

However,itisnotclearwhethertheinformation gatheredfromtheseinspections wasindeedusedintheIPEEEfireanalysis.

b.Significant WalkdownFindingsTheIPEEEdoesnotindicatethatthewalkdownteamdiscovered anynewfirevulnerability fromtheplantvisit.FromtheIPEEE,itcanbeinferredthatthewalkdownwasusedmainlytoverifyequipment andcablelocations, tomeasureareadimensions, andtoconfirmcombustible loadings.

c.Signi/cantPlantFeaturesThefollowing isalistofplantfeaturesthataredeemedtobeimportant:

EnergyResearch, Inc.17ERI/NRC95-504

1.Themainfeedwater pumpsareelectricmotordriven.2.Lossofthecomponent coolingwater(CCW)systemcanleadtoreactorcoolantpump(RCP)sealfailure.3.ThesteamdrivenAFWpumpcanbeoperatedmanually.

4.Thermo-lag isusedforseparation ofredundant trainsinsomeareasoftheplant.TheIPEEEfireanalysishastakencreditfortheeffectiveness ofthismaterialonlyinaselectgroupoffireareas.2.2.3Fire-Induced Initiating Eventsa.WereIniriaring EventsOtherthanReactorTripConsidered?

Reactortrip,lossofoffsitepower,andthepossibility ofaLOCAviareactorcoolantpumpsealfailurehavebeenconsidered intheIPEEE.b.WeretheInitt'aring EventsAnalyzedProperly?

Fromtheinformation providedbythelicensee[1,14],itcanbeinferredthat,forlossofoffsitepowerandreactorcoolantpumpsealfailure,athoroughanalysishasbeenconducted.

However,itisnotclearwhetherthepossibility ofhotshortfailuresincontrolcables,andinadvertent openingoftheisolation valvesofreactorcoolantsystem(RCS)highandlowpressureinterfaces, havebeenconsidered.

Forexample,thepossibility ofapower-operated reliefvalve(PORV)openinginadvertently hasnotbeenaddressed explicitly.

2.2.4Screening ofFireZonesa.WasaProperScreening Methodology Employed?

Screening wasproperlyconducted.

Screening wasperformed perFIVEmethodology.

AlistofallfirezonesisprovidedintheIPEEEsubmittal, alongwiththespecificscreening criteriaandassumptions.

b.HavetheCableSpreading RoomandControlRoomBeenScreenedOut?Thecablespreading roomsandcontrolroomsofbothunitshavebeenincludedinadetailedanalysis, andhavenotbeenscreenedout.C.WereThereAnyFireZones/Areas thatHaveBeenImproperly ScreenedOut?TheIPEEEsubmittal doesnotprovidesufficient information forproperevaluation ofthescreening effort.Fromageneralstandpoint,andwhencomparedwithotherPWRplantsthatareincompliance withAppendixRrequirements, theresultsseemtobereasonable.

Thatis,thefirefrequencies foreacharea,andfailureprobabilities oftheredundant trains,appeartobereasonable.

Manualactionsmayneedtobeundertaken toensureavailability ofaredundant train.Therearenoindications astowhethertheeffectsofaspecificfireontheseactionshavebeenconsidered intheanalysis.

EnergyResearch, Inc.18ERI/NRC95-504 2.2.5FireHazardAnalysisTheIPEEEhasusedthefireoccurrence dataprovidedinReference

[23].Theexactapproach(i.e.,choiceofweighting factors,ignitionsources,etc.)isnotspecified.

Aplant-specific databasehasnotbeenused.PerReference

[14],St.LucieNuclearPlanthasexperienced alowernumberoffireeventsthanfortheaverageplant.Therefore, thisomissioncanbeconsidered as,conservative.

2.2.6FireGrowthandPropagation Firegrowthandpropagation analysiswasaccomplished viatheformulations providedinFIVE.,The submittal providesaseparateappendixwheretheformulations aredescribed.

Themostrisk-significant areawherethesemethodshavebeenusedisthe"B"switchgear room.Reference

[14]providesabriefdescription ofthisarea,butdoesnotprovideanyinformation regarding thesizeandexactlocationofthetransient fuelsthathavebeenconsidered.

Thesubmittal doesnotprovideanydetailsofhowthespecificfirepropagation scenarios weredeveloped, orhowtransient orotherfuelshavebeenpositioned withinthefireareas.a.Treatment ofCross-Zone FireSpreadandAssociated MajorAssumprions AspartofPhase-Iscreening, thefirecompartment interaction analysis(FCIA)methodology ofFIVEhasbeenused.Compartments havebeencombinedtoformalargerfirezonethattakesintoaccountthepossibility offirespreadamongcompartments.

However,possibility offirespreadthroughnormallyopenactivefirebarriers(e.g.,roll-updoorsandfiredampers)hasnotbeenaddressed explicitly.

Giventhediscussions providedinReferences

[1]and[14],itmaybeconcluded.

that,sincethepossibility offirespreadhasbeenconsidered aspartofFCIA,thisphenomenon isofminimalrisksignificance.

Thepotential forfirebarrierfailureresulting fromfirefightingactivities wasnotaddressed.

Anexampleofsuchan'eventmayincludeafireinacompartment withtrain"A"equipment andcables,whileaccesstothisroomisviatheadjacenttrain"B"compartment.

b.Assumprions Associated ivithDetecrion andSuppression Forthemajorityofthecompartments, thespecificfiredetection andsuppression characteristics oftheareawerenotaddressed andanalyzed.

TheIPEEEsubmittal claimsthat,exceptforthecontrolroom,nocreditwastakenformanualfiresuppression.

Asimplemodelwasutilizedforsuppression systemfailure.Itwasassumedthatthereisaprobability of0.1forthefiredetection

'andsuppression systemstofailtostopafirefromdamagingalargearea.Thisassumption wasappliedtosixfireareas(bothunitscombined),

ofwhichtwoareashavebeenscreenedout;Theotherfourareasconsistofthecablespreading roomsandcontrolrooms.Thecompeting phenomenon betweenfirespreadandfiredetection/suppression wasnotmodeled.Also,therearenoindications forthesixfireareasastowhetheradetailedanalysisofthelocations ofthecritical(associated withsafeshutdown) cablesandequipment withinacompartment wasconducted.

Suchananalysisisimportant, sinceinsomecases,itispossibleforcriticalequipment andcablestofail,regardless ofsuppression systemsuccessorfailure.'Energy'Research, Inc.19ERI/NRC95-504 c.Treatment ofSuppression-Induced DamagetoEquipment, ifApplicable InReference

[I]thereisnodiscussion, foranyofthephasesoftheanalysis, ofsuppression-induced damage(i.e.,damagetocablesandequipment asaresultoftheactivation ofthefiresuppression systemtoextinguish asmallfireinthearea).However,aspartofthediscussions onthefireriskscopingstudyissuesraisedbySandia,itisexplained thatallsafety-related areasareequippedwithpre-action typesprinkler systems,whichminimizes thepossibility ofwatersprayontocabinetsandmotors.Additionally, inReference

[14[thisissueisfurtherdiscussed forfiresinthecontrolroom.Cablespreading roomfiredamagecanbemitigated byusingthealternate shutdownpanel.Thus,itcanbeconcluded thattheadverseeffectsofwatersprayone1ectrical equipment areofminimalrisksignificance.

ComputerCodesUsed,ifApplicable Thefirepropagation, detection, andsuppression analysishasbeenperformed usingtheformulations providedinReference

[23].Theformulations aresummarized intheappendixtotheIPEEEsubmittal.

Thelicensee's analystshavedeveloped acomputerized versionoftheformulations, whichhasbeenusedintheanalysis.

2.2.7Evaluation ofComponent Fragilities andFailureModesa.Dejinition ofFire-Induced FailuresThesubmittal providesashortdiscussion onthefire-induced failures.

Thisdiscussion addresses theavailability ofremotelyoperatedvalvesthathaveahand-wheel.

Nodiscussion isprovidedastowhetherornotconsideration wasgiventoinadvertent operation ofequipment andinstrumentation.

b.MethodUsedtoDetermine Component Capaciries Nocriteriaismentioned regarding survivalcapacities ofcablesandelectrical equipment.

GiventhattheFIVEmethodology wasused,AppendixRrequirements havebeenmet,andthecablesareIEEE383qualified, thelicenseeisexpectedtohaveusedtheproperfailurecriteria.

c.GenericFragiliries ThecablesareIEFE383qualified.

Therefore, theoverallconclusions regarding potential forfirespreadandfailureare,ingeneral,acceptable.

d.Plant-Specific Fragiliries Plant-specific f'ragilities havenotbeenused.e.Technique UsedtoTreatOperatorRecoveryAcrionsAsimplemodel(failureprobability of0.1)wasemployedforhumanrecoveryactionsinthecaseofacontrolroomfireoracab1espreading roomfire.Thisapproachandprobability valuehavebeencommonlyusedinotherfireriskstudies,andaredeemedtobesufficiently conservative providedtheplantEnergyResearch, Inc.20ERI/NRC95-504 employsawrittenprocedure forusingthealternate shutdownsystemandconductstrainingdrillsforthisprocedure.

Forfireeventsoutsidethecontrolroomorcablespreading room,thehuman,failureprobabilities embeddedintheinternaleventsmodeloftheIPEhavebeenusedforconditional coredamageprobability estimation.

Reference f14]providesadiscussion oftheoperatoractionsthatmayneedtobeundertaken fromoutsidethecontrolroom.Inallcases,itisshownthatthefireeventcannotaffecttheeffectiveness oftheoperatorfromreachingtherequiredplantarea,andfromconducting theactionitself.2.2.8FireDetection andSuppression Thepossibility offiredetection andsuppression hasbeentakenintoaccountforsixfireareas(bothunitscombined).

Asmentioned inSection2.2.7above,asimplemodelwasused.Aprobability of0.1fordetection andsuppression failurewasusedinthemajorityofthecases.Specificcompartment conditions werenotmodeledexplicitly.

Thisapproachcouldbeoptimistic ifthecriticalcablesandequipment arelocatedwithinasmallpartoftheroom.Inotherwords,regardless offailureorsuccessoffiredetection andsuppression, thecriticalsetofcablesandequipment maybesoclosetogether, thatincaseofafirewithinthatspecificarea,theequipment andcableswouldberenderedfailedbythefirebeforethesuppression systemhasanopportunity tostopthedamage.2.2.9AnalysisofPlantSystemsandSequences a.KeyAssumpnons Including SuccessCriteriaandAssociated BasesThesuccesscriteriaweredirectlytakenfromtheprobabilistic riskanalysis(PRA)oftheplant.b.EventTrees(Funcnonal orSystemic)

TheIPEEEdoesnotprovideanydiscussion astothemodelingmethodsusedinthePRA.c.'ependency Matrix,ifitIsDifferent fromthatforSeismicEventsNodependency matrixhasbeenprovided.

d.Plant-Unique SystemDependencies Thesubmittal doesnotidentifyanyplant-unique systemdependencies ofrelevance tofirerisk.e.SharedSystemsforMuln-Unit PlantTheSt.Lucietechnical supportcenterissharedbetweenthetwounits.Theeffectofthiscenterinrecovering fromaspecificfireeventmaybesignificant.

However,theoveralleffectonthefireriskanalysisresultsisgenerally minimal.Thereisapossibility offeedingpowerfromoneunittotheother.Across-tie breakerisavailable toconnectthedieselgenerator ofoneunittotheotherunit.Thepossibility ofusingthisfeaturehasbeenincludedintherecoveryactionsofatleastsixfirescenarios.

Reference

[14]indicates thatthisrecoveryEnergyResearch, Inc.21ERI/NRC95-504 l

actionistakenfromthecontrolroom,whichisisolatedfromtheplantareaswherethefiremaybepresent.Thisrecoveryactionhasnotbeenconsi'dered forthecontrolroomandcablespreading roomfires.f.MostSigni/cantHumanAnionsTheIPEEEsubmittal doesnotaddresshumanactionsseparately.

Intwoareas,humanactionsarementioned:

incontrolling theplantfromafireinthecablespreading roomorthecontrolroom;andinusingthecross-'tie breakertopoweroneunitfromtheotherunit.2.2.10CoreDamageFrequency Evaluation ThelicenseehasprovidedtwoexamplesofcomputeroutputsfromCAFTAthatdemonstrate theconditional coredamagefrequencies.

Thefirst100minimalcutsetsthatcontribute tothecore'damage frequency arealsoshown.Itshouldbenotedthat,forthesetwoexamples, evenwiththefirst100cutsets,notmorethan80%oftheoverallfrequency isaccounted for.Noconcisesetofscenarios constitutes themajorityofthecoredamagefrequency.

2.2.11AnalysisofContainment Performance a.Signijicant Containment Performance InsightsContainment fireswereconcluded tobeinsignificant forSt.Lucie.EventhoughSt.Luciehasexperienced RCPoilfiresinthepast,thelicensee's conclusion appearstobebasedonthefactthatalargefractionofcontainment fireswereattributed toreactorcoolantpumpoilleaks,andthattheplanthassincebeenequippedwithanoilcollection system.Containment isolation failurewasaddressed explicitly intheIPEEE.Itwasconcluded thattheprobability ofisolation failurefromafireislow.Theanalysisandtheconclusions aresimilartothosereportedforotherPWRs,andtherefore, theyareconsidered reasonable.

b.Plant-Unique Phenomenology Considered Eventhoughitisnotdiscussed specifically inthesubmittal, itisinferredthatthesamephenomenology hasbeenusedasthatintheIPEandPRA.Firesequences andassociated failedequipment wereanalyzedusingtheIPEcontainment eventtrees.2.2.12Treatment ofFireRiskScopingStudyIssuesa.Assumpnons UsedtoAddressFireRiskScopingStudyIssuesSeismicandfireinteraction wasaddressed throughthefailureofthefiresuppression systemanditseffectsonsafetyequipment.

Itisstatedthatfiresuppression designincludesprovisions tominimizeinadvertent actuation fromaseismicevent.Thepossibility offireoccurrence fromseismicactivitywasnotaddressed inthefireanalysisportionoftheIPEEE.EnergyResearch, Inc.22ERI/NRC95-504 tg0t0~Il~

2.Firebarrierswereassumedtobequalified,per theAppendixReffort.Specificprocedures havebeencitedforinspection andmaintenance ofthefiredoors,firedampers,firebarriers, andpenetration sealassemblies.

3.TheIPEEEsubmittal statesthatallplantpersonnel whohaveunescorted accessmustundergofirewatchtraining.

Inaddition, stricttraininganddrillsarerequiredforthefirebrigade.4.Regarding firesuppression systemimpactonsafetysystems,itwasarguedthatallsprinkler systemsservingsafetyareasarepre-action type.Thisfeature,ifthesystemisequippedwithanalarm,wouldminimizethelikelihood ofinadvertent firewaterimpactonsafetysystems.5.Controlsysteminteraction wasaddressed viatheuseofanalternate shutdownpanelandisolation switches.

Asimplemodelwasusedfortheoperators failingtocontroltheplantfromthispanelincaseofacontrolroomorcablespreading roomfire.6.Severalprocedures havebeencitedthataddressdifferent aspectsoffiresatSt.Lucie.Aspecificprocedure exists(although nodetailsareprovided) thataddresses fireemergencies.

Anotherprocedure addresses controlroomevacuation.

b.Significant Findings1.Damagecausedbysuppression systemactuation isnotasignificant issue.2.Thefirebrigadeundergoes sufficient

training, andallpersonnel whohaveunescorted accessactasfire-watch.

Thesuppression systems,insafety-related areas,canwithstand seismicevents,andtherefore, seismically inducedfailureoffireequipment isnotaproblem.4.Inadvertent actuation offiresuppression isnotaproblembecausechargedsystemsarenotlocatedinsafety-critical areas.5.Procedures areavailable thataddressfire-related issues.6.Potential adverseeffects'on plantequipment bycombustion productswerenotaddressed.

7.Barrierfailureswerebasedonthecombustible loadingofthearea.Noconsideration wasgiventothemechanical failureofactivebarriers(e.g.,roll-updoors)..2.2.13USIA45IssueSt.Luciewasoneoftheplantsevaluated bytheNRCfordecayheatremovaladequacy, inthecontextofUSIAA5.EnergyResearch, Inc.23ERI/NRC95-504 a.MethodsofRemovingDecayHearAuxiliary feedwater, mainfeedwater, andfeedandbleedcoolingarethemethodsconsidered forheatremovalduringandafterafireevent.b.AbilityofthePlanttoFeedandBleedSt.Luciehasthiscapability.

c.CreditTakenforFeedandBleedCredithasbeentakenforfeedandbleedcapability.

d.PresenceofThermo-Lag St.LuciecontainsThermo-lag.

Thelicenseehastakencreditfortheeffectiveness ofThermo-lag inalimitednumberofareas.Thisissueisbeingevaluated bythelicenseeatthistime.2.3HEQFxenh2.3.1HighWindsandTornadoes t2.3.1.1GeneralMethodology TheIPEEEsubmittal 1conain[]tsanalysesforbothSt.LucieUnitsIand2.St.Lucie-2begancommercial operation inAugust1983.AllofSt.Lucie-2's components andsystemsrequiredforsafeshutdownarelocatedin,orprotected by,structures thatmeetthelatestStandardReviewPlan(SRP).Thus,the"highwinds/tornado"-induced risktothisunitwasconsidered tobeinsignificant andwasqualitatively screenedout.St.Lucie-1begancommercial operation inDecember1976.Thesubmittal reportsthatthe"highwinds/tornado"-induced risktothisunitwasconsidered tobeinsignificant onthebasisthatall"safety-relatedsystemsandcomponents" are:1.'ocatedwithintornadomissileprotected structures, 2.Providedwithmissilebarriers, 3.Havebeenshownnottobesusceptible tomissileimpactdamage,4.Havebeenshownnottoadversely affectsafetyifdamagedbyamissile,or5.Havealowprobability ofmissiledamage.Theaboveconclusions werereachedbyperforming thefirstfivestepsofthegeneralmethodology presented inSection1.1.3.EnergyResearch, Inc.24ERI/NRC95-504 2.3.1.2Plant-Specific HazardDataandLicensing BasisThesiteisperiodically a6'ectedbythepassageoftropicalcyclonesofvariousintensities, withthemonthsofSeptember andOctoberhavingthehighestfrequency ofoccurrence.

Tornadoes andwaterspouts havebeenobservedthroughout theyearinthatpartofFlorida.Theparameters applicable tothedesign-basis tornadoare:tI~Externalwindforcesfromatornadofunnelwithahorizontal rotational velocityof300mphandahorizontal translational velocityof60mph,foratotalwindvelocityof360mph.~Adecreaseinatmospheric pressureofthree(3)psi.~Impactloadsfromatornadogenerated missile.Theparameters applicable tothedesign-basis tornado,usedforidentification ofsite-specific meteorological conditions, areinagreement withtherequirements ofR.G.1.76[24].ASCEPaperNo.3269[25]andANSIA58.1[26]wereusedtotransform the,windvelocityintopressureloadingsonstructures.

TheSt.Lucie-2missilespectrumisbasedonatornadozoneIsite,asidentified inR.G.1.76.Identification ofapplicable regionalandsite-specific meteorological conditions, andhurricane/tornado windloading,wasperformed usingthesameparameters andprocedures asusedforUnit2.TheUnit1design-basistornadomissilespectrumconsistsofa2"x4"x10'oodplanktraveling at360mph,anda4000poundautomobile traveling at50mph.DuringtheUnit1licensing review,theNRCstaffrequested thattheUnit1capability towithstand amoreextensive missilespectrumbeevaluated.

2.3.1.3Significant ChangesSinceIssuanceoftheOperating LicenseThesubmittal doesnotcataloganysignificant changessincethetimetheplantoperating license(OL)wasissued2.3.1.4Significant FindingsandPlant-Unique FeaturesNosignificant findingsarecitedinthesubmittal.

Asummaryofthewalkdownprocedures usedbythelicensee, andthequalifications oftheteammembersperforming thewalkdown, arenotprovidedinthesubmittal.

2.3.1.5HazardFrequency WASH-1300

[27];aDamesandMoore(DAM)study,aspresented intheSt.Lucie-1FSAR,AppendixF;andNUREG/CR<710

[28]arereferenced inthesubmittal.

However,theNUREG/CRQ710 valuesarethosewhichwereusedfortheevaluation.

EnergyResearch, Inc.25ERI/NRC95-504 2.3.1.6BoundingAnalysisBoundinganalyseswereperformed forthedieseloilstoragetanks,andtheintakecoolingwater(ICW)systemandcomponent coolingwater(CCW)systempipes.Nospecificassumptions havebeenstated.However,thefollowing keyimplicitassumptions seemtohavebeenmade:1.Theconditional missileimpactprobability reported'in NUREG/CR4710 isapplicable tothetargetsunderconsideration inthestudy.2.Threatfromonlyonemissileiscredible.

Thesubmittal reportsthatthefrequency ofdamage(tornadostrikefrequency xmissileimpactprobability) foreachoneofthestructures underconsideration islessthan10~/ry,andscreensoutthecontribution ofthe"tornadoes/high winds"hazardtotheplantoperational riskatthisstageoftheanalysis.

2.3.2ExternalFlooding2.3.2.1GeneralMethodology Themethodology consisted ofidentifying themajoreventsofconcern,assessing thepotential threatpresented bythehazards,andevaluating plantdefensesagainstthesehypothetical events.2.3.2.2Plant-Specific HazardDataandLicensing BasisTheprobablemaximumhurricane (PMH)surgeandprobablemaximumprecipitation (PMP)wereconsidered asthemajoreventsofconcerntoSt.Lucie.Thehydrologic conditions thatwilloptimizethepotential erosionattheSt.Luciesitewereestablished byconducting astudyofhistorical loopingandstalledhurricanes forthetimeperiodof1900to1973.Duringtheprobablemaximumflood,whichresults'from thePMHsurge,thehighwaterlevelis17.2ftmeanlowwater(MLW).Theplantgradeisatelevation

+18.5ft.MLW,andminimumentranceelevation toallseismicCategory-I buildings is+19.5ft.MLW.SeismicCategory-I structures andsafety-related components areprotected fromtheeffectsofhighwaterlevelandwaverun-upthatareassociated withPMHconditions, by:1.Designing structures andcomponents towithstand sucheffectswherefunctionally

required, 2.Positioning ofthestructures andcomponents suchthattheyarelocatedatsufficient gradetoprecludeinoperability duetoexternalflooding, and/or3.Housingthemwithinwaterproof structures.

Thedesign-basis probablemaximumprecipitation for24hours,usedintheanalysis, was24.1inches,overanareaof10squaremilesorless.EnergyResearch, Inc.26ERI/NRC95-504

~7Lw4 Theroofleadershavebeendesignedforarainfallintensity ofsixinchesperhour.Shortperiodsofmoreintenserainfallresultinwaterrunningofftheedgesoftheroofs,withnoadverseeffectstosafety-related equipment.

Nowaterbuild-upontheroofsinexcessof2"ispossible, exceptfortheshieldbuildingdome,whichissurrounded bya1'-6"highparapet.Thesubmittal statesthatnoneoftheaboveconditions adversely affectsthestructures orsafety-related equipment.

Thethreatofdamagefromtheprobablemaximumfloodonstreamsandriverswasdiscounted onthebasisthattherearenosuchwaterways locatedinclosevicinityoftheplant.Theriskfrompotential damfailureswasalsodiscounted, sincenodamsarelocatedwithinthehydrological influence ofHutchinson Island.Theriskpresented bytheprobablemaximumtsunamifloodingwasdiscredited onthebasisthat:(1)thereisnoevidencetoindicatetheexistence ofpotential tsunamigenerators offshoreinthesitearea;and(2)anypossibleeffectsatthesitelocationfromtsunamigenerated fromfar-fielsourceswillbenegligible comparedtotheeffectofsurgescausedbythePMH.2.3.2.3Significant ChangesSinceIssuanceoftheOperating LicenseThesubmittal doesnotcataloganysignificant changesthathaveoccurredsincethetimeofOLissuance.

Thesubmittal doesnotethatthelicenseeconsidered theeffectsoflatest,increased PMPcriteria, andconcluded thattherearenoconcernsassociated withthesitefloodinglevelsorroofpondingthatcouldaccompany anincreased PMP.2.3.2.4Significant FindingsandPlant-Unique FeaturesForUnit2,thedesign-basis eventsforfloodprotection ofsafety-related equipment andfacilities meettherequirements ofR.G.1.59,exceptthatthePMHpertinent tothesiteisthebasisforthecomputation oftheprobablemaximumsurge(PMS).TheR.G.1.59PMSwouldequal+16.7ft.MLW,whereasthesurgeassumedbytheSt.LucieFSARanalysisis+17.2ft.MLW.Thefloodprotection recommendations ofR.G.1.102werefollowed.

TheSt.LucieUnit1safetyevaluation report(SER)wasfinalized beforetheSRPwasissued.Thus,evaluation oftheconformance ofUnit1totheSRPcriteriawasmadebycomparing theUnit1hazardanddesigntothatofUnit2.Thecomparison indicates thattheUnit1floodprotection issimilartoUnit2,andthusmeetstheSRPcriteria.

Thesubmittal doesnotdiscussanywalkdowns thatwereperformed duringtheanalysis.

2.3.2.5.HazardFrequency SincetheSt.LucieUnits1and2designsweredetermined tomeettheR.G.1.59andSRPcriteria, thefloodinghazardwasqualitatively screenedout,andnohazardfrequency wasestimated.

EnergyResearch, Inc.27ERI/NRC95-504

~4~gk 2.3.3Transportation andNearbyFacilityAccidents 2.3.3.1GeneralMethodology Themethodology usedforevaluation oftransportation andnearbyfacilityaccidents consistsofthefollowing steps:1.2.3.4.Reviewofplant-specific hazarddataandlicensing bases;Determination ofconformance oftheplantrisksignificant structures tothe1975SRPcriteria; Screening ofplantstructures

'thatmeettheSRPcriteriaforaspecifichazard;andDetermination ofthehazardfrequency forthosestructures thatdonotmeettheSRPcriteria.

2.3.3.2Plant-Specific HazardDataandLicensi.Ba".sa.AirponsandAirwaysTherearenomajorairportswithin10milesoftheplant.Thenearestmajorairportwithcommercial facilities is48milesfromtheplant.However,thereareseveralsmallerairportsinclosevicinitytotheplant.b.Warerivays TheAtlanticOceanshippinglanesareabout10to15nauticalmileseastoftheplant,thus,noshiporbargeexplosion canaffecttheplantstructures.

BargespassingintheIntracoastal Waterwayaretheothersourceofpotential hazardtotheplant.c.HighwaysThegoverning explosive and/orflammable eventwasjudgedtoariseonStateRouteA1A,whichpassesabout750feeteastofthedieseloilstoragetanks,duetoaliquefied propanetruckaccident.

Thesubmittal statesthattheprobability ofhavingapotential accidentwhoseconsequence canresultinaradionuclide releaseinexcessof10CFR100guidelines issignificantly lessthan10'/yr,basedonthecalculations intheUnit2FSAR.TheresultsintheFSARarereportedtohavebeenvalidated basedondiscussion withlocalauthorities andadrive-through ofthearea.However,sincethereportofthediscussions andthedrive-throughobservations arenotdocumented inthesubmittal, theirconclusions couldnotbeevaluated forthisTER.d.Railroads Thenearestrailroadis2mileswestoftheplant.Thisdistancewasconsidered tobesufficient toprecludeadverseeffectstotheplantfromaccidental explosions ontherailroad.

Chlorineisthemostlikelyhazardous materialtobeshippedontherailcars.Thesubmittal references theUnit2FSARwhichprovidesanevaluation demonstrating thattheprobability ofachlorinereleaseadversely affecting theplantislessthan10~peryear.TheresultsintheFSARanalysisarereportedtobevalidbasedondiscussion withlocalauthorities andadrive-through ofthearea.However,sincethereportofthediscussions andEnergyResearch, Inc.28ERI/NRC95-504 thedrive-through observations arenotdocumented inthesubmittal, theirconclusions couldnotbeevaluated forthisTER.e.ToxicChemicalEventsChemicals thatarenon-volatile orliquids,orthatspontaneously combustinair,werenotconsidered toposeathreattocontrolroomhabitability.

Also,chemicals forwhichtheirpotential forignitionconstitutes agreaterhazardthantheirtoxicity, wereeliminated fromconsideration.

Thethreattocontrolroomhabitability fromthetoxicchemicals whichwerenoteliminated onthebasisofthecriteriastatedabove,wereeliminated byadetailedassessment oftheiratmospheric transport andpotential forinfiltrating intothecontrolroom.Ammoniumhydroxide, whichisstoredonsite;carbondioxide;andchlorine, whichistheprincipal toxicsubstance transported bytheFloridaEastCoastRailway(FECR),arethemajorchemicals forwhichtheirpotential impactoncontrolroomhabitability wasanalyzedindetail.Thethreatsposedbyammoniumhydroxide andcarbondioxideweredismissed onthebasisthattheconcentration ofthesechemicals insidethecontrolroomremainswellbelowthetoxicitylimit.ThethreatposedbythereleaseofcMorineduetoarailroadaccidentwasdismissed basedonthefrequency ofthedesign-basis event.f.Indus(rial Faciliries Therearenomilitarybases,"missile installations, chemicalplants,hazardous materialstorageareasordrillingoperations within10milesofSt.Lucie.Therearenopipelines within5milesoftheplant.2.3.3.3Significant ChangesSinceIssuanceoftheOperating LicenseThesubmittal doesnotcataloganysignificant changessincethetimeofOLissuance.

2.3.3.4a.AirwaysSignificant FindingsandPlant-Unique FeaturesTheestimated numberofoperations peryearfromoneofthelocalairportswasfoundtobegreaterthantheSRPscreening valueof144,000.b.Waterways Considering themaximumsizeofbargespassingtheplantsite;Equation1ofR.G.1.91,"Evaluation ofExplosions Postulated toOccuronTransportation RoutesNearNuclearPowerPlants"[29];andthedistancebetweenanysafety-related structures andthenearestIntracoastal Waterwayshippingchannel,theriskofdamagefromabargeexplosion wasdismissed.

EnergyResearch, Inc.29ERI/NRC95-504

~g 2.3.3.5HazardFrequency a.AirwaysSincetheestimated numberofoperations peryearforalocalairportwasfoundtobegreaterthantheSRPscreening value,theSandiaNationalLaboratories (SNL)[30]andSRPmethodswereusedtoshowthattheaircraftcrashfrequency isbelow10~/yr.b.ToxI'cChemicalEventsTheaccidental releaseoftheentirecontentsofchlorinefromatankcarwasassumedtobeaninitiating eventforadesign-basis accident.

Thefrequency ofsuchaneventwascalculated according tothefollowing equation:

wherePi=annualprobability ofdesign-basis eventunderatmospheric stability ClassI,'nvolving thei-thchemical; P-probability ofadesignbasisaccidentforamobilesourceperunitlengthoftravel;M,=D=jannualnumbersoftripsinvolving thei-thchemical; annualprobability ofanatmospheric stability class;thelengthofroad,rail,orriverinsectorj;FJIwindfrequency fromsectorjtooutsideairintakeofthecontrolroomforstability Class1;andnumberofwinddirection sectors.Usingtheaboveformula,theoverallprobability ofaneventthatmayaffectcontrolroomhabitability wasdetermined tobe1.4x10'/yr.

Therefore, theSt.LucieUnit2designwasdetermined toeithermeettheSRPcriteria, orhavealowhazardfrequency.

Duetotheproximity ofUnits1and2,thehazardanalysisforUnit2was.judged tobeapplicable forUnit1.2.3.4Lightning andOthersThesubmittal presentsadiscussion oftheSt.Lucielightning protection system.BasedonareviewoftheSt.LucieFSARs,theplant'soperating history,andNUREG/CR-4710

findings, thesubmittal concludes EnergyResearch, Inc.'0ERI/NRC95-504 I

thatthereisnouniqueplantvulnerability tolightning atSt.Lucie,andthattheimpactoflightning onplantriskisboundedbytheinternaleventsanalysis.

2.42.4.1GSI-147,"Fire-Induced Alternate Shutdown/Control PanelInteraction" GSI-147addresses thescenariooffireoccurring inaplant(e.g.,inthecontrolroom),andconditions whichcoulddevelopthatmaycreateanumberofpotential controlsystemvulnerabilities.

Controlsystemiinteractions canimpactplantriskinthefollowing ways:Electrical independence ofremoteshutdowncontrolsystemsLossofcontrolpowerbeforetransferTotallossofsystemfunctionSpuriousactuation ofcomponents Asindicated intheresponsetoQuestionII-3inReference

[14],forthepossibility ofoccurrence oflossofoffsitepowerandreactorcoolantpumpsealfailurefromafire,"athoroughanalysishasbeenconducted.

However,itisnotclearwhetherthisanalysisconsidered thepossibility ofhotshortfailuresincontrolcables,andinadvertent openingoftheisolation valvesofreactorcoolantsystemhighandlowpressureinterfaces.

Sincethesubmittal hasfollowedtheguidanceprovidedinFIVEconcerning controlsysteminteractions, allcircuitry associated withremoteshutdownisassumedtohavebeenfoundtobeelectrically independent ofthecontrolroom.2.4.2GSI-148,"SmokeControlandManualFireFightingEffectiveness" GSI-148addresses theeffectiveness ofmanualfire-fighting inthepresenceofsmoke.Smokecanimpactplantriskinthefollowing ways:~Byreducingmanualfire-fighting effectiveness andcausingmisdirected suppression efforts~Bydamagingordegrading electronic equipment

~Byhampering theoperator's abilitytosafelyshutdowntheplant~Byinitiating automatic fireprotection systemsinareasawayfromthefireReference

[31]identifies possiblereduction ofmanualfire-fighting effectiveness andmisdirected suppression effortsasthecentralissueinGSI-148.Manualfire-fighting wasnotcreditedintheanalysis.

Thus,theissueofmanualfire-fighting effectiveness isnotaddressed inthisTER.2.4.3GSI-156,"Systematic Evaluation Program(SEP)"Reference

[31]providesthedescription ofeachSEPissuestatedbelow,anddelineates thescopeofinformation thatmaybereportedinanIPEEEsubmittal relevanttoeachsuchissue.Theobjective ofthissubsection isonlytoidentifythelocationintheIPEEEsubmittal whereinformation havingpotential relevance toGSI-156maybefound.EnergyResearch, Inc.31ERI/NRC95-504

Settlemenr ofFoundarions andBuriedEquipment IEI:hbjifbiSEPiikfy.systemsandcomponents areadequately protected againstexcessive settlement.

Thescopeofthisissueincludesreviewofsubsurface materials andfoundations, inordertoassessthepotential staticandseismically inducedsettlement ofallsafety-related structures andburiedequipment.

Excessive settlement orcollapseoffoundations couldresultinfailuresofstructures, interconnecting piping,orcontrolsystems,suchthatthecapability tosafelyshutdowntheplantormitigatetheconsequences ofanaccidentcouldbecomprised.

Thisissue,applicable mainlytosoilsites,involvestwospecificconcerns:

~potential impactofstaticsettlements offoundations andburiedequipment wherethesoilmightnothavebeenproperlyprepared, andseismically inducedsettlement andpotential soilliquefaction following apostulated seismicevent.Sincestaticsettlements arenotbelievedtobeaconcern,thefocusofthisissue(whenconsidering relevantinformation inIPEEEs)shouldbeonseismically inducedsettlements andsoilliquefaction.

Itisanticipated thatfull-scope seismicIPEEEswilladdresstheseconcerns, following theguidanceinEPRINP-6041.St.Lucieisareduced-scope plant,andCategoryIstructures forbothunitsarefoundedonCategory-I fill,underlaid bycementedsandsandsandylimestones.

TheIPEEEsubmittal providesnodiscussion ofthepotential andeffectsforseismically inducedsettlements.

orsoilliquefaction.

Information onsitegeologycanbefoundinSection2.2ofReference

[5].DamIntegrt'ty andSiteFloodingt31:biifhi'ii0liifpfloodingandtoensureacoolingwatersupply.Thesafetyfunctions wouldnormallyincluderemaining stableunderallconditions ofreservoir operation, controlling seepagetopreventexcessive uplifting waterpressures orerosionofsoilmaterials, andproviding sufficient freeboard andoutletcapacitytopreventovertopping.

Therefore, thefocusistoassurethatadequatesafetymarginsareavailable underallloadingconditions, anduncontrolled releasesofretainedwaterareprevented.

Theconcernofsitefloodingresulting fromnon-seismic failureofanupstreamdam(i.e.,causedbyhighwinds,flooding, andotherevents)isaddressed aspartoftheSEPissue"sitehydrology andabilitytowithstand floods."Theconcernsofsitefloodingresulting fromtheseismicfailureofanupstreamdamandlossoftheultimateheatsinkcausedbytheseismically inducedfailureofadownstream damshouldbeaddressed intheseismicportionoftheIPEEE.Theguidanceforperforming suchevaluations isprovidedinSection7ofEPRINP-6041.Asrequested inNUREG-1407, thelicensee's IPEEEsubmittal shouldprovidespecificinformation addressing thisissue,ifapplicable toitsplant.Information includedforresolution ofUSIA-45isalsoapplicable tothisconcern.TheSt.LucieIPEEEsubmittal states(onpage79)thatnodamsarelocatedwithinthehydrological influence ofthesitelocationonHutchinson Island.EnergyResearch, Inc.32ERI/NRC95-504 IW'~

~~~~SiteHydrology andAbilitytoWithstand Floodst3I.'biifUiii<<idifyhihdgihinordertoensurethecapability ofsafety-related structures towithstand

flooding, toensureadequatecoolingwatersupply,andtoensurein-service inspection ofwater-'control structures.

Thisissueinvolvesassessing thefollowing:

Hydrologic conditions

-toassurethatplantdesignreflectsappropriate hydrologic conditions.

Floodingpotential andprotection

-toassurethattheplantisadequately protected againstfloods.JUltimateheatsink-toassureanappropriate supplyofcoolingwaterduringnormalandemergency shutdown.

Asrequested inNUREG-1407, thelicensee's IPEEEsubmittal shouldprovideinformation addressing theseconcerns.

Theconcernrelatedtoin-service inspection ofwater-control structures, acompliance issue,isnotbeingcoveredin.theIPEEE.TheSt.LucieIPEEEsubmittal (Section5.2)hasincludedadiscussion ofexternalfloods,including effectsofhurricane stormsurge(pages76to78)andprobablemaximumprecipitation (pages78,79,and82).Industrial Hazardsl3'I:hbifui'iU<<hiffstructures, systems,andcomponents wouldnotbejeopardized duetoaccidenthazardsfromnearbyfacilities.

Suchhazardsinclude:shockwavesfromnearbyexplosions, releasesofhazardous gasesorchemicals resulting infiresorexplosions, aircraftimpacts,andmissilesresulting fromnearbyexplosions.

Asrequested inNUREG-1407, thelicensee's IPEEEsubmittal shouldprovideinformation addressing this'ssue.TheSt.LucieIPEEEsubmittal (Section5.3)includesthefollowing information ofrelevance tothisissue:Section5.3.1ofthesubmittal identifies nearbytransportation routes;Section5.3.2discusses nearbyindustrial facilities; Section5.3.3discusses offsiteandonsitesourcesofhazardous materials orexplosives; Section5.3.4discusses hazarddataforairportsandairways;Section5.3.5discusses hazarddataforexplosions; andSection5.3.6discusses potential toxicchemicalevents.TornadoMissilesbi<<i'i"'i'Ip9>>(SEPplants)areadequately protected againsttornadoes.

Safety-related structures, systems,andcomponents needtobeabletowithstand theimpactofanappropriate postulated spectrumoftornado-generated missiles.

Asrequested inNUREG-1407, thelicensee's IPEEEsubmittal shouldprovideinformation addressing thisissue.TheSt.LucieIPEEE(Section5.1)hasinvolvedanevaluation oftornadoes, including tornado-induced missiles.

Detailedinformation andevaluation oftornado-induced missilesisprovidedinSection5.1.1.EnergyResearch, Inc.33ERI/NRC95-504 SevereWeatherEffectsonStructures

[31]:Theobjective ofthisissueistoassurethatsafety-related structures, systems,andcomponents aredesignedtofunctionunderallsevereweatherconditions towhichtheymaybeexposed.Meteorological phenomena tobeconsidered include:straightwindloads,tornadoes, snowandiceloads,andotherphenomena judgedtobesignificant foraparticular site.Asrequested inNUREG-1407,thelicensee's IPEEEsubmittal shouldprovideinformation specifically addressing highwindsandfloods.Othersevereweatherconditions (i.e.,snowandiceloads)weredetermined tohaveinsignificant effectsonstructures (seeChapter2ofNUREG-1407).

,TheSt.LucieIPEEEhasincludedevaluations ofhighwinds(hurricanes, andtornadoes) andexternalfloods.Section5.1ofthesubmittal discusses hurricanes andtornadoes, andSection5.2ofthesubmittal discusses externalfloods.Section5.4ofthesubmittal includesanevaluation forlightning.

DesignCodes,Criteria, andLoadCombinarions t3f:Thbii"fhiii<<h<<ipfyshouldbedesigned, fabricated, erected,andtestedtoqualitystandards commensurate withtheirsafetyfunction.

Allstructures, classified asSeismicCategoryI,arerequiredtowithstand theappropriate designconditions withoutimpairment ofstructural integrity ortheperformance ofrequiredsafetyfunctions.

Duetotheevolutionary natureofdesigncodesandstandards, operating plantsmayhavebeendesignedtocodesandcriteriawhichdifferfromthosecurrently usedforevaluating newplants.Therefore, thefocusofthisissueistoassurethatplantCategoryIstructures willwithstand theappropriate designconditions (i.e.,againstseismic,highwinds,andfloods)withoutimpairment ofstructural integrity ortheperforma'nce ofrequiredsafetyfunction.

AspartoftheIPEEE,licensees areexpectedtoperformanalysestoidentifypotential severeaccidentvulnerabilities associated withexternalevents(i.e.,assesstheseismiccapacities oftheirplantseitherbyperforming seismicPRAsorSMAs).TheSt.LucieIPEEEhasincludedanevaluation ofpotential vulnerabilities associated withexternalevents.Thesubmittal doesnotsystematically identifycodes,criteria, andloadcombinations usedindesign.However,Sections2.5,and3.1to3.5ofReference

[5]providesomeinformation relatedtoseismicdesignofstructures andequipment; Section51oftheIPEEEsubmittal providesinformation relatedtowinddesignofstructures; Section5.2containssomeinformation relatedtodesignconditions forwithstanding floods;andSection5.3ofthesubmittal providesinformation ondesigncriteriarelatedtotransportation andnearbyfacilityaccidents, including explosions.

SeismicDesignofStructures, Systems,andComponents

[31]:Theobjective ofthisSEPissueistoreviewandevaluatetheoriginalseismicdesignofsafety-related structures, systems,andcomponents; toensurethecapability oftheplanttowithstand theeffectsofaSafeShutdownEarthquake (SSE).TheSt.LucieIPEEEisbasedontheseismicadequacyevaluation performed aspartofthelicensee's resolution ofUSIA-46concerns(Reference

[5]).Sections2.5and3ofReference

[5]providesomeinformation relatedtotheseismicdesignofstructures andcomponents, andSection4ofReference

[5]providesadescription oftheapproachandfindingsoftheseismicadequacyevaluation.

EnergyResearch, Inc.34ERI/NRC95-504 ShutdownSystemsandElectrical Instrumentarion andControlFeaturest3I'.th'l

'lh3Ifplreliableshutdownusingsafety-grade equipment.

Theissueonelectrical instrumentation andcontrolistoassessthefunctional capabilities ofelectrical instrumentation andcontrolfeaturesofsystemsrequiredforsafeshutdown, including supportsystems.Thesesystemsshouldbedesigned, fabricated, installed, andtestedtoqualitystandards, andremainfunctional following externalevents.InIPEEEs,licensees wererequested toaddressUSIA45,"Shutdown DecayHeatRemoval(DHR)Requirements,"

andtoidentifypotential vulnerabilities associated withDHRsystemsfollowing theoccurrence ofexternalevents.Theresolution ofUSIA-45shouldaddressthesetwoissues.St.LucieNuclearPlanthadbeenusedasacasestudyplantbySandiaNationalLaboratories forprobabilistic evaluation ofdecayheatremovaladequacy, inthecontextofUSIA<5.Thisissuewasaddressed aspartoftheIPEEE,ingeneral,andpertinent information isprovidedinSections4.9and5.1(page72)ofthesubmittal.

Sections2.1.13and2.2.13ofthisTERsummarize reviewfindingsrelatedtoUSIA<5,respectively, forseismiceventsandfireevents.2.4.4GSI-172,"Multiple SystemResponses Program(MSRP)"Reference

[31]providesthedescription ofeachMSRPissuestatedbelow,anddelineates thescopeofinformation thatmaybereportedinanIPEEEsubmittal relevanttoeachsuchissue.Theobjective ofthissubsection isonlytoidentifythelocationintheIPEEEsubmittal whereinformation havingpotential relevance toGSI-172maybefound.CommonCauseFailures(CCFs)RelatedtoHumanErrorst33:CCPIIIthII3fomissionthatcouldbeinitiating events,orcouldaffectredundant safety-related trainsneededtomitigatetheevents.OtherhumanerrorsthatcouldinitiateCCFsinclude:manufacturing errorsincomponents thataffectredundant trains;andinstallation, maintenance ortestingerrorsthatarerepeatedonredundant trains.InIPEEEs,licensees wererequested toaddressonlythehumanerrorsinvolving operatorrecoveryactionsfollowing theoccurrence ofexternalinitiating events.Averylimiteddiscussion ofoperatorrecoveryactions,following aseismicevent,isprovidedinSection4.4ofReference

[5].Section4.6ofthesubmittal providessomediscussion onthetreatment ofhumanrecoveryactionsintheinternalfireanalysis.

Non-Safety-Related ControlSystem/Safety-Related Protecrion SystemDependencies impactonsafety-related protection systems,asaresultofpotential unrecognized dependencies betweencontrolandprotection systems.Theconcernisthatplant-specific implementation oftheregulations regarding separation andindependence ofcontrolandprotection systemsmaybeinadequate.

Thelicensees'PE processshouldprovideaframework forsystematic evaluation ofinterdependence betweensafety-related andnon-safety-related systems,andshouldidentifypotential sourcesofvulnerabilities.

Thedependencies betweensafety-related andnon-safety-related systemsresulting fromexternalevents-i.e.,concernsrelatedtospatialandfunctional interactions

-areaddressed aspartof"fire-induced alternate EnergyResearch, Inc.35ERI/NRC95-504 shutdownandcontrolroompanelinteractions,"

GSI-147,forfireevents,and"seismically inducedspatialandfunctional interactions" forseismicevents.Information providedintheSt.LucieIPEEEsubmittal pertaining toseismically inducedspatialandfunctional interactions isidentified below(undertheheadingSeismically InducedSparialandFunctional Interacrions),

whereasinformation pertaining tofire-induced alternate shutdownandcontrolpanelinteractions hasalreadybeenidentified inSection2.4.1ofthisTER.Heat/Smoke/Water Propagarion EffectsPomFirest3I:difIpif*.NIIdtraincouldpotentially bedamagedinoneoffollowing ways:Heat,smoke,andwatermaypropagate (e.g.,throughHVACductsorelectrical conduit)intoasecondfirezone,anddamagearedundant trainofequipment.

Arandomfailure,notrelatedtothefire,coulddamagearedundant train.Multiplenon-safety-related controlsystemscouldbedamagedbythefire,andtheirfailurescouldaffectsafety-related protection equipment foraredundant traininasecondzone.Afirecancauseunintended operation ofequipment duetohotshorts,opencircuits, andshortstoground.Consequently, components couldbeenergized orde-energized, valvescouldfailopenorclosed,pumpscouldcontinuetorunorfailtorun,andelectrical breakerscouldfailopenorclosed.Theconcernofwaterpropagation effectsresulting fromfireispartially addressed inGI-57,"EffectsofFireProtection

.SystemActuation onSafety-Related Equipment."

Theconcernofsmokepropagation effectsisaddressed inGSI-148.Theconcernofalternate shutdown/control roominteractions (i.e.,hotshortsandotheritemsjustmentioned) isaddressed inGSI-147.Information providedintheSt.LucieIPEEEsubmittal pertaining toGSI-147andGSI-148hasalreadybeenidentified inSections2.4.1and2.4.2ofthisTER.Section4.8ofthesubmittal presentssomelimitedinformation pertinent tothisissue.EjjectsofFireSuppression SystemActuarion onNon-Safety-Related andSafety-Related Equipment

[31]:Firesuppression systemactuation eventscanhaveanadverseeffectonsafety-related components, eitherthroughdirectcontactwithsuppression agentsorthroughindirectinteraction withnon-safety relatedcomponents.

Items2and5ofSection4.8ofthesubmittal presentsomelimitedinformation pertinent tothisissuesectsofFloodingand/orMoistureIntrusion onNon-Safety-Related andSafety-Related Equipment

[31]:Floodingandwaterintrusion eventscanaffectsafety-related equipment eitherdirectlyorindirectly throughfloodingormoistureintrusion ofmultipletrainsofnon-safety-related equipment.

Thistypeofeventcanresultfromexternalfloodingevents,tankandpiperuptures, actuations offiresuppression systems,orbackflowthroughpartsoftheplantdrainagesystem.TheIPEprocessEnergyResearch, Inc.36ERI/NRC95-504 addresses theconcernsofmoistureintro'ton andinternalflooding(i.e.,tankandpiperupturesorbackflowthroughpartoftheplantdrainagesys!;m).Theguidanceforaddressing theconcernofexternalfloodingisprovidedinChapter5ofNUREG-I"07,andtheconcernofactuations offiresuppression systemsisprovidedinChapter4ofNUREG-1407.

Thefollowing information isprovidedr:l,vanttothisissue:externalfloodingisdiscussed inSection5.2oftheSt.LucieIPEEEsubmittal, andItems2and5ofSection4.8presentsomelimitedinformation concerning inadvertent actuation offi;esuppression systems.Seismically InducedSpatialandFunct'anal Interacrions

[31]:Seismiceantshavethe.potential tocausemultiplefailuresofsafety-related systemsthroughspatialandfunctional in',era:tions.

Someparticular sourcesofconcerninclude:rupturesinsmallpipingthatmaydisablee.<<entiai'plant shutdownsystems;directimpactofnon-seismically qualified structures, systems,andconponentsthatmaycausesmallpipingfailures; seismicfunctional interactions ofcontrolandsafety-reiat";>r>><ection systemsviamultiplenon-safety-related controlsystems'ailures; andindirectimpacts,suchasd~~~'eneration, disabling essential plantshutdownsystems.AspartoftheIPEEE,itwasspecifically reque~'..i thatse!smi:ally inducedspatialinteractions beaddressed duringplantivalkdowns.

Theguidanceforperoiiningsuchwalkdowns canbefoundinEPRINP-6041.TheSt.Lucieseismicadequacyevali:ation

{Reference

[5])hasincludedaseismicwalkdownwhichinvestigated thepotential foradverseIhy~i'alinteractions.

Relevantinformation canbefoundinSection4.7(particularly Section4.7.2.3)ofReference

[5].Seismically InducedFires~zgjpIign~zJ~~

[31]:Sei~~al!yindu'edfiresmaycausemultiplefailuresofsafety-related systems.Theoccurrence ofaseisnii'vent cnuidcreatefiresinmultiplelocations, simultaneously degradefiresuppression capability, andpreventmitigation offiredamagetomultiplesafety-related systems.Seismically inducedfiresisi>>neaspectofseismic-fire interaction

concerns, whichisaddressed aspartoftheFireRiskScopingStudy{)=RSS)issues.{IPEEEguidancespecifically requested licensees toevaluateFRSSissues.)InIPEEEs,~e~mt."a!l~inducedfiresshouldbeaddressed bymeansofafocusedseismic-fire interactions walkdownthatfollowstheguidanceofEPRINP-6041.Section4.8ofthesubmittal verybr!fi~'i~cu<<es seismic-fire interactions; however,noevaluation ofseismically inducedfiresisprovided~partoftheSt.LucieIPEEEsubmittal.

Seismically InducedFireSuppression SystemActuanon[31]:Seis-">>ceventscanpotentially causemultiplefiresuppression systemactuations which,inturn,maycai'-'-":.ilures ofredundant trainsofsafety-related systems.Analysescurrently requiredbyfireprotection ieg,ilations generally onlyexamineinadvertent actuations offiresuppression systemsassingle,independent events,whereasaseismiceventcouldcausemultipleactuations offiresuppression systemsinvariousareas.Items2and5ofSection4.8ofthe:-;<<';;i-al;resent somelimitedinformation pertinent tothisissue.2EnergyResearch, Inc.37ERI/NRC95-504 Seismically InducedFloodingtill:WMlyidkfliiillyIiiiiiiofsafety-related systems.Ruptureofsmallpipingcouldprovidefloodsourcesthatcouldpotentially affectmultiplesafety-related components simultaneously.

Similarly, non-seismically qualified tanksareapotential floodsourceofconcern.IPEEEguidancespecifically requested licensees toaddressthisissue.TheSt.LucieIPEEEsubmittal hasnotincludedadiscussion ofseismically inducedflooding.

Seismically InducedRelayChatterWlihW<<ii~qe,ioneofthefollowing conditions:

remainfunctional (i.e.,withoutoccurrence ofcontactchattering);

~.beseismically qualified; or~bechatteracceptable.

Itispossiblethatcontactchatterofrelaysnotrequiredtooperateduringseismiceventsmayproducesomeunanalyzed faultingmodethatmayaffecttheoperability ofequipment requiredtomitigatetheevent.IPEEEguidancespecifically requested licensees toaddresstheissueofrelaychatter.AsnotedinSection2.1.9ofthisTER,theSt.LucieIPEEEsubmittal doesnotmentionrelaychatterevaluation.

However,duringNRC'sUSIAWreviewofTurkeyPoint,Units3and4,andSt.Lucie,Unit1,itwasrevealedthatthelicenseehadassessedbadactorrelays,verifiedmountings ofrelays,anddemonstrated thattherewerenodeleterious effectsofchatterofbadactorrelays.TheNRCacceptedthelicensee's relayevaluation forUSIA<6resolution.

Evaluanon ofEarthquake Magnitudes GreaterthantheSafeShutdownEarthquake

[31]:Theconcernofthisissueisthatadequatemarginmaynothavebeenincludedinthedesignofsomesafety-related equipment.

AspartoftheIPEEE,alllicensees areexpectedtoidentifypotential seismicvulnerabilities orassesstheseismiccapacities oftheirplantseitherbyperforming seismicPRAsorseismicmarginsassessments (SMAs).Thelicensee's evaluation forpotential vulnerabilities (orunusually lowplantseismiccapacity) duetoseismiceventsshouldaddressthisissue.St.Lucieisdesignated asareduced-scope plantinNUREG-1407, andconsistent withtherelevantguidelines forareduced-scope plant,theIPEEEhasconsidered seismicinputequivalent totheSSElevel.Earthquake loadsinexcessoftheSSEhavenotbeenconsidered.

sectsofHydrogenLineRuptures[31j:Hydrogenisusedinelectrical generators atnuclearplantstoreducewindagelosses,an'dasaheattransferagent.Itisalsousedinsometanks(e.g.,volumecontroltanks)asacovergas.Leaksorbreaksinhydrogensupplypipingcouldresultintheaccumulation ofacombustible mixtureofairandhydrogeninvitalareas,resulting inafireand/oranexplosion thatcoulddamagevitalsafety-related systemsintheplants.Itshouldbeanticipated thatthelicenseewilltreatthehydrogenlinesEnergyResearch, Inc38ERI/NRC95-504

,~

~~~1andtanksaspotential fixedfiresourcesasdescribed inEPRI'sFIVEguide,assesstheeffectsofhydrogenlineandtankruptures, andreporttheresultsinthefireportionoftheIPEEEsubmittal.

Section5.3.3oftheSt.LucieIPEEEsubmittal identifies compressed hydrogenasapotential explosion

,source;however,nodiscussion pertaining tohydrogenlinerupturesisprovidedinthesubmittal.

EnergyResearch, Inc.39ERI/NRC95-504

~~

3OVERALLEVALUATION ANDCONCLUSIONS 3.1SeiSaIlCTheapproachchosenbythelicenseeforresponding totheseismicIPEEEdoesnotaddressallrelevantissuesandconcernsforSt.LucieNuclearPlant,areduced-scope site.Acomparison ofmajorfeaturesoftheFPLseismicadequacyprogramwiththeguidelines forareduced-scope seismicevaluation, issummarized inTable3.1below.Ascanbeseenfromthistable,theprimarydeficiencies oftheFPLapproachare:asignificantly lesserscopeofcomponents intheFPLapproach; alimitedtreatment ofhumanactionsfortheSt.Luciestudies;andnotreatment ofcontainment systemsintheFPLprogram.Table3.1Comparison ofFPL'sSite-Specific SeismicIPEEEProgramVersusNUREG-1407 Recommended Guidelines foraReduced-Sco eSeismicEvaluation ElementofIPEEEEvaluation WalkdownRelayEvaluauon SoilFailuresScreening CriteriaSeismicInputEvaluation ofOutliersNon-Seismic FailuresandHumanAcuonsContairunent Performance Assessment USIARSGI-131Reduced-Scope Evaluation Guidelines ScopeshouldincludeallSSELactivecomponents andpassivecomponents (structures,

raceways, heatexchangers, tanks.piping.etc.)nccdedtoensurecompleteprcferrcd andalternate successpaths.USIAWevaluation forUSIAA6plant;Noevaluation fornon-USIAMplant.Noevaluation isnecessary.

SRTjudgment; GIPscreening guidance; Anchorage checkbasedonSSEspectmmandFSARin.structure responsespectrumgRS).SSEspectrumandFSARIRS(ornewmeanplusonc-sigma IRS).GIPprovisions forUSIAMItems;FSARrequirements fornonUSIAMitems.Theseshouldbcqualitatively addressed; successpathsarechosentoscreenoutvulnerability totheseitems.Walkdown, screening, andoutlierevaluation ofcontainment structure andcomponents ofcontainment systems.Walkdown, screening, andcvaluauon ofdecayheatremovaloutlicrs.

Walkdown, screening, andevaluation ofseismicadequacyoffluxmappingsystem.FPL'sSite-Specific SeismicAdequacyProgramScopeincludesSSELactivecomponents andgt)itspassivecomponents (tanks,heatexchangers);

component listappearsincomplete; sclectcdsuccesspathsnotidentilicd.

USIAA6treatment ofelectrical racewayswasapprovedbytheNRC[7]Badactorevaluation forSt.Lucia-l,approvedbyNRCforUSIAM[71;Noevaluation forSt.Lucie-2.Noevaluation.

SRTjudgment; SSRAPboundingspectrum; Anchorage checkbasedonSSEspectrumandFSARIRS.SSEspectrumandFSARIRS.Conservative calculation ofcapacityversusdcmat;d;demandbasedonconservative uscofSSEspectrumandFSARIRS;HCLPFcalculations forlargeQat.bonomed tanksatSt.Lucia-2.Limitedqualitauve evaluation ofactionsassociated withsuccesspath.Noevaluation.

Nospecificevaluation; onlypartially addressed inchosensuccesspath.Notapplicable toSt.Luci>>.Inaddition, theformatfordocumenting theseismicIPEEEwasnotwellstructured, anddidnotfollowtherecommendations ofNUREG-1407.

EnergyResearch, Inc.40ERI/NRC95-504 Despitethesesignificant deficiencies, theSt.Lucieseismicevaluations do,nonetheless, addresssomemeaningful IPEEE-related

concerns, andhaveresultedinasmallnumberofplantseismicsafetyenhancements.

Furthermore, theNRChasalreadyapprovedmanyaspectsofthelicensee's seismicadequacyevaluation approachforUSIAWresolution

[6,7]thatpertainalsototheseismicIPEEE.Basedonthissubmittal-only review,andinconsideration oftheNRC'sfindingsforUSIA-46,thefollowing itemsareidentified astheprimarystrengths andweaknesses oftheseismicIPEEEsubmittal forSt.LucieNuclearPlant:1.Thestudyimplements ameaningful approachforscreening andoutlierevaluation ofthelimitedsetofcomponents itaddresses.

2.Theuseofhighlyexperienced seismicwalkdownexpertshasbeenconsistent withthestudy'sheavyrelianceonSRTjudgments.

3.Anumberofoutliershavebeenidentified, andmeaningful corrective safetyenhancements havebeenproposed.

1.TheSSELisdeficient.

2.Aseismiccontainment performance assessment wasnotconducted.

3.Thetreatment ofhumanactionsisdeficient.

4.Thesubmittal doesnotprovideadequatedocumentation ofseismic-fire/fiood interaction

concerns, including component-specific walkdownfindings.

5.TheseismicIPEEEisincomplete withrespecttoreduced-scope evaluation recommendations foundinNUREG-1407.

6.TheseismicIPEEEsubmittal isnotdocumented inaccordance withtheformatrecommended inNUREG-1407, AppendixC3.2EggThelicenseehasexpendedconsiderable effortinthepreparation oftheSt.LuciefireIPEEE.TheIPEEEreportcomplieswiththeconditions setforthinReference

[3].Thelicenseehasemployedapropermethodology anddatabaseforconducting thefireanalysis.

TheFIVEmethodology hasbeenusedforthispurpose.Thefollowing arethestrengths andweaknesses ofthesubmittal:

,EnergyResearch, Inc.41ERI/NRC95-504 1.Theoverallpresentation isclearandwell-organized.

Therearetaf>lesandfigurestoprovideinformation tosupporttheanalysisandtheconclusions.

3.FStatecf-the-art methodology andproperdatahavebeenused.Basedonthedatapresented, itcanbeconcluded thatthelicenseehasconducted areasonable analysis.

Theoverallresultsarewithintherangeofconclusions reachedinotherPWRfireriskstudies.Ecakm~1.Thepossibility ofhotshortsandresulting RCSfailurefromafireeventhasnotbeenaddressed explicitly intheIPEEEsubmittal.

Firesuppression systemfailureprobability maynothavebeenusedproperly.

Ifacriticalsetofcablesandequipment arewithinasmallregionofacompartment, thesuccessful operation ofthefiresuppression systemmaynotmatter.3.Probability offailureoftheredundant equipment andmodelsusedforarrivingattheconditional probability ofcoredamagegivenafirescenariohavenotbeenexplained insufficient detail.4.Cross-zone firepropagation, whereactivefirebarriersareemployed, wasnotaddressed explicitly.

Thesubmittal doesnotprovidesufficient information forthereviewers tobeabletoverifysuchaspectsoftheanalysisas:theprobability ofredundant trainfailuresgivenafire,fire-induced initiating events,damagefromfiresuppression systemactivation, andfiremodelingandhotshorts.6.Thesubmittal doesnotaddressthepossibility ofaseismiceventleadingtoafire.7.Thereareseveralcompartments forwhichthefrequency ofcoredamageisslightlylessthan10~/ry.Theseareas,althoughmarginally withinthescreened-out range,havenotbeenaddressed inanydetail.Certainly, notwithstanding theaboveobservations, thelicenseehasgainedanimportant experience fromtheexerciseofanalyzing theplantforpotential firevulnerabilities.

3.3HE~LEzenh Ingeneral,theconclusions ofthesubmittal areadequately supported andfollowtheacceptedpracticeandguidelines ofNUREG-1407.

Threecategories ofHFOeventsareaddressed insomedetail:highwindsandtornadoes, externalflooding, andtransportation andnearbyfacilityaccidents.

Noparticular weaknesses werefoundinthesubmittal regarding thelasttwocategories.

EnergyResearch, Inc.42ERI/NRC95-504 Thefollowing providesadescription oftheareasinthehigh-winds/tornadoes analysisthatcontainconclusions whicharedifficult toverify:Twooftheintakecoolingwater(ICW)valveoperators inthevalvepitwereidentified asbeingpotentially vulnerable toverticalmissiles.

Ifoneorbothvalvesbecomeinoperable, manualvalvescanbeusedtoensureadequateICWflow.Thereportconcludes that"sincethevalveoperators arelocatedbelowgrade,arephysically wellseparated, haveanalternate meansavailable toisolatethetie-lines totheturbinewatercoolingsystem,andhaveredundant systemsavailable,"

adequatetornadoprotection hasbeenprovided(page56,lastparagraph).

However,thereportdoesnotspecify:(1)whetheraprocedure exists,orsufficient timewouldbeavailable, forperforming thecited-manual action;(2)onwhatbasisitisconcluded thatthevalvesare"wellseparated";

and(3)wherethealternate components arelocated.Formanystructures, theinherentcapability ofthestructure wascreditedtoaccommodate aspecifichazard-forexample,theCCWheatexchangers andpiping(page57,thirdparagraph).

Itappearsfromthesubmittal thatifastructure isjudgedtobeabletowithstand asinglemissile,thenithasthecapacitytowithstand simultaneous (concurrent) impactbyseveralmissiles.

Onpage58,lastparagraph, itisstatedthatthedieseloiltanksare"sufficiently separated toprovideanacceptable leveloftornadoresistance capability,"

withoutproviding abasisforthisstatement.

Onpage59,secondparagraph, itisstatedthat"...acommitment hasbeenobtainedfromalocalfuelcompany,...,

tosupplyfueloilona24-houremergency basis."However,fromtheexplanation providedinthereportitisnotclear:(a)(b)that,intheeventofdieseloilstoragetankunavailability, sufficient onsitefueloilwouldbeavailable tooperatethedieselgenerators beforethearrivaloftheoffsitefueloil;andthattheassumption thatthelocalfuelcompany's oilsupply,oritsmeansofoildelivery, wouldnotbeaffectedbythesametornadothatispostulated tohitthesite,isvalid.Inadditiontotheaboveambiguities, determination ofthehazardfrequency (starting frompage69)issomewhatconfusing, andcontainsthefollowing potentially optimistic assumptions andsuppositions:

~Thestudyreferences theNUREG-1407 statement that,iftheoriginaldesigndoesnotmeetthe~bUoriginaldesignbasisissufficiently low,suchthattheestimated coredamagefrequency islessthan10'/ry(page70).Inthesubmittal, asfaras"tornadoes/high winds"hazardisconcerned, theabovestatement isinterpreted tomeanthat,ifthecontribution tocoredamagefrequency asaresultofatornado-induced damagetoanyonetargetislessthan10~/ry,thenthattargetcanbeexcludedfromfurtherevaluation.

Usingthisinterpretation, somepotential targetsarescreenedbasedonthelowfrequency ofhazardcriterion, andtheremaining onesbyperforming boundinganalyses(page73).Thisinterpretation, however,isoptimistic andunderestimates thepotential risk.Toscreenahazard,thecumulative riskinducedbythathazardhastobebelowthescreening value,nottheEnergyResearch, Inc.43ERI/NRC95-504

~~individual risksfromeachpotential target,since,forexample,atornadocanimpactmorethanonetarget,andwillgeneratemorethanonemissile.Onpage71,thirdparagraph, itisstatedthat,inevaluation oftornadomissiles, inadditiontoweighingtheprobability ofacertain-intensity-tornado occurring andgenerating amissile,thefollowing mustbeconsidered:

P4=Probability thatamissile,ifgenerated, willimpactthecomponent; P,=Probability that,ifstruck,lossofsystemfunctionoccurs;andP,=Probability thatanindependent singlefailureoccursinthestruckcomponent's redundant counterpart.

Thesubmittal assumesavalueof10'orP4,byreferencing adocketedShearonHarriscalculation formissileimpactonaservicewaterpump.However,nocomparison betweenthecharacteristics oftheservicewaterpumplocationandthelocationoftheSt.Luciepotential targetswasmade.SincetheP,valueishighlylocationspecific, assumingavalueof10'orP,maybeoptimistic.

Thesubmittal alsoprovidesascreening reviewofotherexternaleventsthatmaypresentapotential severeaccidentvulnerability atSt.LucieUnitsIand2,asummaryofwhichispresented inTable5-23ofthesubmittal.

Basedonthisscreening, forestfiresareclaimedtohaveaminimalpotential impactontheplant,andtheimpactisconsidered tobeboundedbylossofoffsitepower.However,thepotential impactofsmokegenerated bythefiresonthecontrolroomhabitability, onequipment, andonlossofcleanairandinstrument airarenotaddressed.

Ingeneral,theapproachappearstobesound.However,acomprehensive screening ofallpotential externalfiresourcesandtheireffectshasnotbeendocumented.

EnergyResearch, Inc.ERI/NRC95-504 4IPEEEINSIGHTS, IMPROVEMENTS)

ANDCOMMITMENTS 4.15ehmzThekeyseismicIPEEEfindingsareprimarily walkdownrelated;fewquantitative insightshavebeenderivedfromtheseismicevaluations.

Thus,novaluesforseismiccoredamagefrequency, plant-level fragility capacitynorplant-level HCLPFcapacityhavebeenestimated asaresultoftheseismicIPEEE.Theseismicadequacyevaluation forSt.Lucie-Irevealedanumberofoutliersforwhichsafety.enhancements havebeenproposedorimplemented inresponsetoUSIA46;interaction concernswerealsonoted.ForSt.Lucie-2,findingsrelatedtointeraction

concerns, butnooutlierswerenoted.Enhancements forIPEEE-only components,(i.e.,

components outsidethenormalscopeofUSIA46,butwithinthescopeofIPEEE)werenotaddressed.

Inaddition, containment performance evaluation andevaluation ofhumanactionswerenotincludedaspartofthelicensee's treatment ofseismicIPEEEconcerns.

Thenotedconditions, andproposedsafetyenhancements, aresummarized below:Sr.LucieUnitIDuringthewalkdowns, fiveanchorages andthecomponent coolingwatersurgetankplatformwereidentified asconcernsbytheSRT.Inadditiontothesefiveanchorage

concerns, sixadditional anchorage concernswereidentified byFPLforsimilarcomponents indifferent equipment trains.Themodifications undertaken fortheidentified concernsaredescribed below:-Theexistinganchorboltsarecorroded.

Therepairmodification forthetanksinvolvestheremovalofallexistingcorrosion, application ofprotective

coatings, installation ofcoverplatestoencloseeachanchorboltpocket,andapplication ofafillermaterialtoprotecttheboltsfromfuturecorrosion.

IbibibkdTheanchorage modification involvestheadditionofsupplementary filletweldsalongtheinteriorofthecabinetbase.-Thecabinetisburned-through inareasnearexistingwelds.Themodification consistsofscrewingclipanglestothesidesofthecabinetandanchoring theclipanglestothewallbehindthecabinet,usingexpansion anchorbolts.-Filletweldsaremissingbecausetheexistingembeddedsupportchannelsarenotproperlylocated.Themodification consistsofinstalling platestoconnectthebaseofthecabinetstotheembeddedchannels.

-Severalbracingmembersrequiredbytheoriginalplatformdesignaremissing.Themodification requiresinstallation ofadditional structural members,toincreaselateralstiffness, andrelocation ofaninstrument airlineandthreetankdrainlines.j-Thisloadcenterisforthepressurizer heater,anditconsistsof.threecabinetswithweakanchorage.

Themodifications include:(a)insuringthatthecabinetsareEnergyResearch, Inc.45ERI/NRC95-504

~ft adequately connected, sotheywillactasasingleunitunderseismicloading;and(b)addingfilletweldsattheinteriorbaseofloadcentercabinetstoanchorthemtotheembeddedchannels.

Thefollowing seismicinteraction concernsatUnit1werealsonoted:Potential interaction involving theglasssitetubeforthecomponent coolingwatersurgetank.2.Potential interaction involving ablockwalladjacenttothecomponent coolingwatersurgetank.3.Anoverheadcraneadjacenttotheintakecoolingwaterpumpshouldbesecuredawayfromthepump.Inaddition, somecasesofpoorseismic"housekeeping" wereobservedanddocumented.

InresponsetotheNRC'sUSIA46reviewprocess,thelicenseeisimplementing aprogramofstrictseismichousekeeping.

St.LucieUnit2Twoseismicinteraction concernswerenoted:1~Possibletippingofacabinetnearsafety-related equipment; and2.Questionable supportofacomponent mountedabovesafety-related equipment.

Bothoftheseissueswereultimately evaluated andresolved.

HCLPFcalculations wereperformed foranumberoflargestoragetanksatUnit2;thesecalculations demonstrated thecapacities tobebeyondthedesignbasis.'concernwasalsonotedpertaining towhether'or notthemountingofsomeinternalcoilsinanenergized transformer wasseismically adequate.

Thisconcernwasinvestigated duringanoutage,anditwasfound'hatthemountingwasadequate.

Itwasalsostatedintheseismicevaluation thatawalkdownofwalltransformers neededtobeperformed, todetermine whetherornotthesetransformers wouldneedtobesecured.Inaddition, thepeerreviewresultedinthefollowing additional findingswhichhavebeenaddressed:

Secureloadcenterover-cabinet crane/winches, andverifythattoolboxcartintheswitchgear roomiseitherremovedorproperlysecured.Secureorremovel&Clockerfromcontrolroom.Reducebatteryrackendgapsonthe2Aand2Bbatteries.

Implement control-room housekeeping improvements regarding storageofScottAirPacksandimmobilizing anunsecured locker.EnergyResearch, Inc.-46ERI/NRC95-504 4.2Overall,thelicenseehasconcluded thattherearenosignificant firevulnerabilities atSt.Lucie.Withtheexception ofthecontrolroom,cablespreading room,andthe"B"Switchgear room,allfirezonesandareaswerescreenedoutbasedon10~/rycoredamagefrequency criterion.

Thecoredamagefrequencies forfiresinthecontrolroomswereconcluded tobe7.49x10'/ry and5.90x10'/ryforUnitsIand2,respectively.

Forthecablespreading rooms,thecoredamagefrequencies wereevaluated tobe6.95x10'/ryand5.64x10'/ryforUnits1and2,respectively.

Forbothareas(i.e.,controlroomandcablespreading room),thelicenseehascitedseveralconservative assumptions infireoccurrence rateandfireseverity, andconcluded thatthesetwoareasdonotposeavulnerability:

Thecoredamagefrequency ofafireinthe"B"switchgear roomwasconcluded tobe4.30x10'/ry and4.48x10~/ryforUnits1and2,respectively.

Firepropagation modelinghasbeenperformed forthisarea,andthelicenseehasconcluded thatfirewillnotpropagate throughout theroom.TheentirefireIPEEEeffort,ofcourse,hasprovidedanexcellent opportunity forthelicensee's engineers tobetterlearnaboutthecharacteristics oftheplant,theplantbehaviorunderdifferent fireconditions, andtheimpactofhumanactionsthatarenecessary toprotectthereactorfromanyadverseeffects.4.3HEQXmdsTheIPEEE'soverallconclusion regarding thiscategoryofexternaleventsisthatanypotential coredamagescenariohasanextremely lowfrequency incomparison withthefrequency ofcoredamagefromotherinitiators.

Asaresult,nosafetyenhancements havebeenidentified, andconsequently, nocommitments aremadethatwouldrequiretrackingbytheNRC.EnergyResearch, Inc.47ERI/NRC95-504 5IPEEEEVALUATION ANDDATASUMMAI(YSHEETSCompleted dataentrysheetsfortheSt.LucieNuclearPlantIPEEEareprovidedinTables5.1to5.6.Thesetableshavebeencompleted inaccordance withthedescriptions inReference

[11].Table5.1liststheoverallexternaleventsresults.Table5.2summarizes generalseismicdatapertaining totheevaluation.

Tables5.3providestheSeismicSuccessPathsOverviewTable,andTable5.4summarizes sequenceinformation forPWRSeismicSuccessPaths.Accidentsequenceinformation providedinTables5.5and5.6forfireeventsareonlypartially completed duetolackofsufficient information providedinthesubmittal

[1]andReference

[14].AccidentsequencetablesarenotprovidedforHFOevents,sincenoPRAanalyseswereperformed fortheseevents.EnergyResearch, Inc.48ERI/NRC95-504 Tahle5.1ExternalEventsResultsPlantName:EventExternalFireScreening 0CDFPlantHCLPF(g)NotesExternalFlooding0ExtrcmeWinds0InternalFireNearbyFacilityAccidents 0SeismicActivityTransportation Accidents 0Others0Hazardous chemicals andlightning Scrccning:

S=Plantspecificanalysis; 0=Screenedout;SO=BoundinganalysisEnergyResearch, Inc.49ERI/NRC95-504 1

Table5.2SSMSeismicFragility PlantName:~MphReviewLevelEarthquake (g):SpectralShape:'ig'NUREG4098, NRCGuide1.60,10,000yearLLNLmedianUHS,SiteSpecific, orother)Listcomponents andequipments whichdonotmeetRLE(allcomponents) orwithlowestHCLPF(lessthan10):Component'ondensate StorageTank(Unit2)RWST(Unit2)DieselOilStorageTank(Unit2)BoricAcidMakeupTanks(Units1and2)HCLPF(g)>0.3g(but(0.49g)>0.3g(hut(0.64g)1.47gSeismicSequenceDescription SeismicSuccessPathDescription NotalllowestHCLPFswerereported; reduced-scope evaluation.

EnergyResearch, Inc.50ERI/NRC95-504 Table59PWRSuccessPathOverviewTablePlantName:~+ggjiSequenceSuccessPathPDSHCLPF(L)'nitEventT-LOOPSuccessSupportsEAC,CCW,ESWNon-Failed Functions Attributes jttjLatssLjjttjtjsxtn:

oneoftbe(oasis)nst si,S2.s3,A,v[.ss),T.Loot',T-Rx,T-Tf,T-hlvrs,T.UHs,T-RcP.T.LNMv.T.LMptv,T.Expttr.

TQBoc.T<LBIc,T~T~Rvlloav, TWCI,T-(other),

orT-(Support System)(.xs)referstooptionalsuppkmentaty mater(al.

QSISI~sSISBt htmostteooftbefoaesdeS:

AC.ACBUI.ACSV2,ACBU3,AUXC~AVXC3.AUXGI.CCIVIDC,EAC,EDC,ESASI,ESAS2,ESttr,HVACI,HVAC2.HVAC3,IA.NIT,OA3,OA4,SA,SIM,StV2,SNr3,S)Vd,VAC(p)aidmaybeblast).tt~tjjDLK)ttt(3jst)tt htmostthreeofthefoaosrbtf tsINT,sDEp,ssMU,RcssoR.Rcs!NT.RcsDEp,Hpl,HPR,LPI.LpR,cpsi,cpsRclp.YENT(lfs4thand/or3thsieneoessary, usetheNotesrield)iBBjj3aut Atmosttbseeoftbefoaotshtf tATWS,SYPASS,11L,IND4GIR,SBO,ORHUM(Valdmsybebien))Redused-Seeps PlanenoHCLPPrapash)etispotted.

EnergyResearch, Inc.51ERI/NRC95-504 Tahle5.4PWRSeismicSuccessPathsPlantName:CHALLENGESTRATF.GYSUCCESPA'rHPRIMARYINTEGRITY PPRAACDDPI2SRBPPPIPSS0RRVVCHLAIiprcPIICIAIIPRIMARYINVENTORY-INJECllON AI2CHPRHLAPPRRRIAR2PRIMARYINVENTORY-

.RECIRCSECONDARY INTHiRITY SSTGGTSAMSIVSECONDARY INVENTORY TSMBGiFWNISPAAAFMMWI2M3CCFSSCI2IFC2ICCCIII2CONTAINMENT I(INRFNOTEST.LoopggggggOneofthcfolkstgSl.S2.S3.A.V(xx).TLOOPTRX,TTr.TA1WS.TUHS.TRCP.T.LNMII.TMFWTEXFWT-SUIOC,TCUIIC.T.SOT)AT-SORY/IORV, T~l.T-(Other).

ORT.(Support System).(.xx)referstooptionalsuppkmcntary material.

AcronymofSupportSystems:AC,ACBUI,ACB'II2,ACBU3.AUXC2.AUXC3.AUXC4,CCW.DC.EAC,EDC,ESASI,ESAS2.ESW.IIVACI.HVAC2,HVAC3.IA.NIT,OA3,OA4,SA,STM.SW2,SW3.SW4,VACI,2,3...How manyneededtooperateHwHumanactknrequiredT=Mustbcthmttkdlcontrollcd ForCoreDamagePrevention Challenges, showonlyhanlwarewhosefailureismodckdascontributing tocoredamage.EnergyResearch, Inc.I52ERI/NRC95-504 C.Table5.5PWRAccidentSequenceOverviewTablePlantName:iniiForFirePRAOnlyIhfSequenceUnitI-ControlRoomPDSCDF7.49x10-s/Init.EventLostSupportsFailedFunctions Attributes UnitI-CableSpreading Room6:96x10'/ryUnitI-BSwitchgcar Room4.30x10's/ryT-RX(inferred)

SSMUUnit2-ControlRoom5.90x10s/ryHUMUnit2-CableSpreading Room5.64x10'/ryUnit2-BSwitchgcar Room448x10s/ryT-RX(inferred)

SSMU,HPIHUM,TIL(infcrrcd)

FA-121/51W 2.67x10'/ryT-RX(infcrrcd)

SSMUHUM,TIL(infcrrcd).

FAW1.34x10s/ryT-RX(inferred)

EPSSMUHUM,TIL(inferred)

TQO!her),orTgsupport System)(-xx)referstooptionalsupplementary inataiat.

rIdtstSutltRxt<

AtmosttwooFthefollowing:

AC,ACBU1,ACBU2,ACBU3,AUXC2.AUXC3,AUXC4,CCW,DC,EAC,EDC,ESAS1,ESAS2,ESW,HVACI,HVAC2,HVAC3,IA.NIT,OA3,OA4,SA,STM,SW2,SW3,SW4,VAC(Fieldmay beblank).~aikdutldsistn:

Atmostthfeeofthe following:

SINT,SDEP,Sshfu,RC<BOR,RCS-INT,RCS-DEP,HPI,HPR.LPI,LPR.CPSI,CPSR,CIF,VENT(lfa4thand/or5tharenecessary, usethe"Notes"Iield)~luilI:Alatadlhr flhfllaaiaSATASS,BYPASS,TII RI~GTR.SBO,ORIIIMIFi idaaayhahla&I EnergyResearch, Inc.53ERI/NRC95-504 tqt Table5.6PWRAccidentSequenceDetailedTablePlantName:ForFirePRAOnlyPRIMARYINTEGRITY PRIMARYINVENTORY-INJECTION PRlhIARYINVENTORY-RFXIRCSECONDARY INTEGRITY SECONDARY INVENTORY CONTAINMENT SEQUENCEUnitI-ControlRoomUnitI-CableSprctalina RoomUnitI~8Switchgcar Room.Unit2-ControlRoomUnit2-CableSprcralinaRoomRPSPPPPSA0RDRVIV122112PRCHACHPDPI'2SI?1LPIAACICAI2CHHPPRR172272AASRRG2SSGATMTTS8IVSGMNAFIFWSWPXXXXXXXXAMIAACMMS23ICS2FFICCCI2CIICIRIGF2NHflMXNOTESlinit'2-8Switchacar Room7FA.I2IISIWFA.OXXIEnergyResearch, Inc.54ERI/NRC95-504 6REFERENCES "Individual PlantExamination ofExternalEventsforSt.LucieUnits1and2,"FloridaPowerandLightCompany,December1994.2."Individual PlantExamination ofExternalEvents(IPEEE)forSevereAccidentVulnerabilities-10CFR50.54(f),"

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SeniorSeismicReviewAdvisoryPanel,January17,1990.22."FireInducedVulnerability Evaluation (FIVE)",ElectricPowerResearchInstitute, TR-100370, Revision1,September 1993.23."St.LucieProbabilistic RiskAssessment,"

preparedforFloridaPowerandLightCompanybyPLG,Inc.,PLG4637,July1988.24."DesignBasisTornadoforNuclearPowerPlants,"Regulatory Guide1.76,April,1974.-

25."WindsForcesonStructures,"

Transactions oftheAmericanSocietyofCivilEngineers, Vol.126,PartII,ASCEPaperNo.3269,1961.26."Building CodeRequirements forMinimumDesignLoadsinBuildings andOtherStructures,"

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