ML17332A848

Qualitative Functional Diversity Assessment of UFSAR of Common Mode Failure of Digital Equipment Software.

ML17332A848
Person / Time
Site:	Cook
Issue date:	12/04/1992
From:	AMERICAN ELECTRIC POWER SERVICE CORP.
To:
Shared Package
ML17332A849	List: ML17332A848 ML17332A850 ML17332A851 ML17334B552
References
QA-92-18, NUDOCS 9507180137
Download: ML17332A848 (87)

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".'tectrfc PowerServiceCorporation learSafetyAndUcenslngSectionCatcttlation CovevSheetNUC159199(R1040glP2SCalculation No.SubjectCAVAyA0tlSpryteSSafety-Related SystemYes+noSupersedes Gale.No.cMcprComPanyTy1AH1dCalculated ByR.5SwVerified/Checked ByMethodOfVenficabon ApprovedByJ/8w9'mbiem

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ENGINEERING DEPT.AMERICANELECTRICPOWERSERVICECORP.1RIVERSIDE PLAZACOLUMSUS, OHIOCOATCOMPANYSHEET2OF~CK~52G.O.gUBJpCgQualitative Functional DiversiAssessment TableofContentsA,Statement.

ofPurpose,andExecutive SummaryB.Assumptions,

.C..Analysis...

Page.Ho.3.....,...

3f...3..D.E.F.Verification

.Results,Discussion ofResults3...3...G..References...,

.H.Table.1.AppendixAAppendixB.I3~4p\5......1-48.

...1-5..~v~'I~F

7223(9S9)FQR<oE4(cIENQINQQRING DEPT.AMERICANELECTRICPOWERSERVICECORP.1RIVERSIDE PLAZACOLUMBUS, OHIOOATCOMPANYSHEET+OFBGKG.G.SU8JECT.UAVEFUNCTONADSSSMA.StateetoPuoseadExecutveSummaSeepage4/5B.C.SeeAppendixA~Aaasis~litative Evaluation giveninAppendices AandBD.Theevaluation wasdonebasedonU2FSAR.ThereviewercheckedUnit1FSARforconsistency.

@CAP11902anditssupplement, RTPLicenseReport,@CAP12135,RTPEngineering Report,QCAP's'12078and12901.InputandOutputData,andUnit2cycle8RTSRwerealsousedasabasisforreviewing theevaluations.

Plantannunciator responseprocedures wereusedtoreviewpossibleandpx'obable alarms.Discussions withHEDpersonnel especially Z&Cpersonnel resolvedvariousissuessuchaswhichalarmswereindependent ofthenewdigitalequipment.

%herethereviewerfeltitwasappx'opriate ornecessary, changestotheevaluation wereproposedandresolvedwiththeevaluator.

esutsSeeAppendixAF.DscussonoeutsSeeAppendixAG.eerencesSeeAppendixA3/5 722%9.d3l ENGINEERING DEPT.AMERICANELECTRICPOWERSERVICECORP.1RIVERSIDE PLAZACOLUMBUS, OHIOCOMPANY.'LANSHEETOFScxG.O.$ugJp(,yQualitative Functional Diversity Assessment STTOFPURPOEANDEXECUTIVE SUMMAROnApril21,1992,AEPSCrepresentatives hadameetingwiththeNRConthereplacement ofexistinganalogreactorprotection processinstrumentation withdigitalFoxboroSpec200/Spec200MicroEleceronics instrumentation.

Duringthismeeting,AEPSCwasaskedtoassumeacommonmodefailure(CMF)ofthesoftwareofthenewdigitalequipment duringanaccideneandthenprovidedetailsastowhetheroperaeors couldmitigatetheconsequences oftheaccident.

Inresponsetothisrequest,afunctional diversity assessment ofeachupdatedFSAR(UFSAR)eventassumingacommonmodefailureofthesoftwarehasbeenperformed.

Inthisassessment, alltheeventsforbothUnits1and2oftheCookNuclearPlanegivenineheUFSARwereconsidered.

Areviewwasperformed todivideeventsintopotentially affectedandnotaffected.

Table-1liststheseeventsandindicates whethertheywouldbepoeeneially affectedornoeaffected, ifaCMFweretooccur.Thepotentially affectedtransients werethenindividually evaluated qualitatively inlightoftheFSARanalysisasshownintheateachedAppendixA.Thetransienes whicharenoeaffectedbythesoftwarefailurearediscussed inAppendixB.~Thefirstcolumnoftheevaluations intheAppendixAcontainth'eUFSARtransient numberlistedinTable-1.Thesecondcolumnincludesthenameofthetransient.

Thethirdcolumndepicesthetrip/safeguard

&mctionforreactortrip.Thisinformation wasobtainedfromtheUFSAR.Thefourthcolumnincludestheinformation ontheimpactofcommonmodefailureonthereactortripfunction.

Ifehetripfunctionisprocessed outsideofthenewdigitalreaceorprotection

~ys~em,thenthetripisavailable, e.g.,triponnuclearinstrumentation systemhighflux.Ifehetripisprocessed byafunctionthatisapartofthenewdigitalequipmene, thenthetrip/ESFfunctionisassumedtobelose.However,forsomefunctions, alternate indicaeions and/ordiversealarmsareavailable.

Thealarm/alternate indications ehaeareavailable toeheoperatortomieigatethetransient aregiveninthenextcolumn.Thesixthcolumnliststhepertinene diagramnumbers.Theseventhcolumnsummarizes theconsequences oftheunavailability ofdiversealazm.Thelastcolumnprovidestheevaluation oftheevent.Inthiscolumn,wehavediscussed eheconsequences oftheoperator's responseonreactorsafety.Basedonthisevaluation, wehaveconcluded thattheCMFofthenewdigit1equipment hasnosxgnxfxcant adverseimpactonthepublicsafeey.Somereactortripsarenoeaffectedbytheinstallation ofthenewdigitalequipment-thesetripsazeneutronhighfluxandhighracetrips,undervoltage andunderfrequency tripsandreaceortriponturbinetzip.However,foreventsprotected bytripsandaceuaeions affeceedbyCMF,shouldaCMFoccur,theoperatorwillbealertedtotheevenebyanalarmfromadiversesystem.Hevillthenprovidetheappropriaee aceuaeions manuallyandentertheemergency operating procedures.

Forsomeaccidents, suchaslockedrotor,theconsequences couldbemoreseverethancurzenely analyzeddueeothelongerresponseeimefortherequiredactuation.

However,ourevaluation indicates thattheaffectedunitcanbebroughttoasafecondition andehecurrentLOCAoffsieedoseevaluation willremainbounding.

Fromtheseresults,ieisbelievedthataCMFofthenewdigiealsystemwouldhavenoadverseeffectonthehealthandsafetyofthepublic.-4/5 1's

?22~(9.6>I ENGINEERING OEPT-AMERICANELECTRICPOWERSERVICECORP.1RIVERSIDE PLAZACOLUMBUS, OHIODATCOMPANYSHEETG.G.SUBJECTUFSARTRANSIENT 414~l.114.1.214.1.314.1.414e1.514.1.614.1.714.1.814.1.914.1.1014.1.11.14.1.1214.1.13ualitative Functional DiversitAssessment

~ab1e-TRANSIENT nconcxolled RCCAWithdraval fromaSubcxitical Condition ncontrolled RCCAWithdrawal atPowerodClusterContxolAssemblyMisalignment CCADropChemicalVolumeandControlSystemMalfhnction ssofReactorCoolantFlovStaxtupofanInactiveReactorCoolantLoopLossofExtexnalElectrical LoadssofNormalFeedvater FlovExcessive HeatRemovalduetoFeedwater:Sys'tern Malfunction Excessive LoadIncreaseIncidentssofAllA.C.PowertothePlantAuxiliaries uzbine-Generator SafetyAnalysisPOTENTIALLY AFFECTED(A)/NOTAFFECTED(NA)AAAAAAAAAAAAA14.2.114.2.214.2.314.2.414.2.514.2.614.2.714.2.8FuelHandlingAccidentccidental ReleaseofRadioactive Liquidsccidental WasteGasesReleaseSteamGenerator TubeRuptureupcuxeofaSteamPipeuptux'eofaContxolRodDriveMeBMI~Housing(RCCAEjection)Secondary SystemAccidencs DoseConsequences

]oxRuptureofaMainFeedvacer PipeAAAAAAAA14.3.114'.214.3.314.3.414.3.514.3.614.3.714.3.8LargeBreakLOCAAnalysisssofReactorCoolantfromSmallRupturedPipesorfromCracksinLargePipeswhichActuatestheEmergency CoreCoolingSystemCoreandInternals Integrity AnalysisContainmenc Integxicy AnalysisEnvironmental Consequences ofaLossofCoolantAccidentydrogenintheContainment AfteraLossofCoolantccidencLongTermCoolingitxogenBlanketing AANAAAANANA14.4.214.4.314.4.414.4.514.4.614.4.714.4.814.4e914.4.1014.4.11SDCDCPEEPostulated PipeFailureAnalysisOutsideContainment nalysisofEmergency Conditions tressCalculations escription ofPipeWhipAnalysisompartment Pressures andTemperatures escxiption ofJetImpingement LoadAnalysisontainment Integrity lantModifications nvironment leetricalEquipment Environmental Qualification NANANANANANANANANAA APPENDlXA

~UNIIIandfsARTRANSIENT NLt.L.lIRANSIENIUncontrolled RCCASankMlthdroualtron~Subcrltlcal Condition IRIP/SAfECUARD fUNCTIONfORRXTRIP(FEARLN~L.i)1.Sourcerangeneutronfluxtrip-ectwtcd sheneitherof2Independent sourcerangechNNttsIAdlcatcs

~flUx~bove4prcsclcctcd, 44NJILLyadjustable value.2.Intcrncdlete rangeneutronfluxtrfpactwtcdUhcn~lthcroftuoIdependent Lntcrocdlate r4Agcchannelsindicates Ifluxaboveaprcselcctcd, auxuLLyad)ustable value.3.Poucrrangehighneutrontluxtripllousetting)"

~ctuatcdebentuooUt0'fCpokerch4NNLIIAdlcatc~flUx4boveIpproxioatcty 25XoffulLpoucrtlux.S.PouerrangenCutrontluxleveltripthighsetting)-

actuateduhcn2outotSpacerrangechanclsIndicate~tluxLcvcL4bova~presetsctpolnt.

5.Inaddition, RxtripfroaPERhighprcssureservesIsIhookuptotcnelnato theIncidentbeforeanovcrprcssUro ccndltloA couldoccurIHPACTOFCO&0KNODEfAILURELCNf)CN'TRIPFUNCTIONItenNos.I.SnotaffcctcdLNcnodatedSept2,1992tressV.G.SotostoV.D.Vandcrgurg, 1/STabl~3.3-I)LOSTLNccodatedRcpt.2,1992tronV..G.SotostoV.0.Vandcrsurg)

ALARN/ALIERNAIE INDICATION STSTENAVAILASLF Ad~cnAYblPanelIndication PanelRecorderPlantProcessCooputcrIAdlcatloA YbPrcssurtcrNighPrcssureDcvlatlon vl~ControlSystca.fourhighprcssUre~LarosYI4~ccntrolsystca.0A~AdcnAudblendicatonofrod~etion.DIACRANSFD.2101SheetI/6coxsfouENcEs 0FUNAVALLASLLLTT OFDIVERSEALARNNotAffectedNone.TuoDiverseALaresareavailable.

EVALUATION OfEVENTThistransient Isnotsffcotcdbythercploccncnt ofN.lineanalogprocessprotectlcnsystcnbyFoxboroSPEC200IndSPEC200NICRO,~Icroproccss basedsgdutcs.TripsIthroughS,ListedlnColum3,arenotaffected, sincerwetcarInstnnentatlon forfluxscasurcocnt lsno!replaced.

forRxtripfrcotprcssurltcr highprcssure, tuodiverse~Laresareavailable.

Inacklltfcn, pressurizer highprcssuretripIsabackuptrip.1 UNIIIFSARTCA<<SIENI 41(.1.2TRANSIENT Uncontrolled SCCASankVlthdra<<al etPa<<crTRIP/SAFECUARD FUNCTIONfORRX1RIP(TSAR)l(~I,g,)1.KualcarPa<<crrangeInstrlsacntstlon aatwtcs~reactortriponhighneutrontluxif2/Cchannelsexceedonovert<<war sctpolnt.

2.Rxtripcnanyt<<ooutoffouritahalv>>tsexceedOIC'1sctpolnt.

Thiscatpolntlsautaeattaatty varied<<lth~xl~Ltxwcrdistribution coolantaveragetccpcrature

~rdpr~scutetoprotectagainstDNS.3.Rxtripont<<ooutoffouratchannelscxaccdOPalsatpotnt.

ThissctpolntIsauteaatlaallyvaried<<1thcoolantaverageteapcrature sothattheallo<<abt~fueLparerratingIsnotcxcccdcd.

C.Ahighprcssurereactortrip,actuatedfresanyt<<aoutoffourprcssurechannelslssctat4fixedpoint.S.*highpressurizer wterlevel,aatwtcdfretsany2/Cahalv>>ts~Issctat4fixedpoint.IHPACIOfCOHHONHCOEFAILINIE(CNf)ONTRIPFUNCTICHNotAffectedOta'fRxTripLost(Ncaadated9/2/92tresV.0SotostoVD.Vandcrgurg)

CPUTRxtripLost(Ncaadated9/2/92fresV.0.SotostoV.D.Vacdcrgurg)

Lost(Ncaadated9/2/92fresV.0.Rotc>>toV.D.Vandcrgurg)

Lost(Nceodated9/2/92fra4V.O.SotostoV.D.Vandcrgurg)

ALARH/ALTERNATE INDICATION STSTENAVAILABLE NISpaverrangeovcrpo<<er rodstepat103X~tar>>.Vt*rangeteapcrature recorders.

Viderangetccperature recorders.

nd4AvabPanelIrdlcatonPanelrecorderPlantProcessaaaputcrlndtaattonvA~AvajbPrcssurltcr NighPrcssureDcv!ation viacon'tI'oL systeaFourNighprcssure~Lars>>viacontrolsystea~AvaabPanellndc4tonPanelrccordcraacputcrIIdlaatlon v4AvsabPrcssurzcrNghLevelDeviation viacontrolsysteaNighlevelviacontrolsystea0tha4ndtaaansAudlbtendicatIonofrodnationDIACRAHSfD2102Sheet3/CFD2102'heet 3/CFD.2102SheetI/dFD2101Sheet2/dco<<sEQUENcfs ofUNAVAILABILIIT OfDIVERSEALARHNuclearII>>truacntat lancystcanotchanged.fivediversealarc>>available 1<<odiverse~lars>>~vallabl~.Rxtriponhigh'prcssurtzcr

<<sterlcvclactuates~alcr~heithertheO~iorhighneutronfluxtrtpAuctionstodeaanstrate thisprotecttonduringprcssurtzcr fillingscenarios (fSAR,page1C.'I:2AC)EVALUATION OfEVENtTheRxtripanMISoverpwcrsetpolntlcnat~ffcatcdbythercptaacsent ofM.lineanalogprocessprotection systea,sincefluxecasureacnt Instruacntatlon lsnotreplaced.

2.1he0141RxtrlPlslostbyN-linercptaaeaant.

ThcOtaltripcnsurcsthatDNSdoesnotoccur.IheFSARanalystsofthisevent~ssuaasthatRxtriponhighprcssurlzcr

<<sterlevellsassusadavailable.

Thistripactuatesearlierthan~IthertheOTC'Iorhighneutronfluxtripfu>>tlanstodeaanstratc thisprotection duringthesto<<crprcssurlzcr fillingscenarios (FSAR,pageTC.T.2A.C).

1hchighpressurizer

<<sterLeveltriphsst<<odiversehighlevelatars>>,therefore operator<<ouldgetindlaattons priortoOtitRxtripforprcssurlzer fllLevents.Thosescenario'c thatdonattcrsdnate onhighNISIfuxorhighprcssurlzcr

<<steraretcratnatcd byOtal.IhcyterdtobeLo<<erreactivity lnsertfon sacnarlos orLcwerpa<<crscenarios.

Althoughnarctinefsavailable forresponsetotheseevents,Itcannotbestated<<lthcertainty thatfuelcladdaoage<<tllnatoccur.Vcsttnghouse hasreportedfnVCAP.B330 thatNtntausONBRcanbcachievedfor~rod<<tthdra<<al atpa<<srATVASatthoughtheparttaular caseevaluated

<<asarapidrcaattvlty Inscrtlon case<<htah<<outdhavetrippedonMIShighflux.CladdaaageIsanacceptable autaaeebaausethcCHFlcasadttptefailurecondition.

Na<<ever,asdiscussed betou,rod<<lthdra<<at of@acreventsaresignificantly nltlgatcd bythefulLpwcrbaseloadoperation oftheCookUnits.3.Thercptaaeacnt ofN.Lineanalogprotection systeacauses~lossofOPiTRxtrip.thlccouldresultInfuelrodcladdingfailure.Ha<<ever,theposslblLlttcs ofthtstooccurlsstl4.FirstofaLL,thiscvcntwuldbetcralnated assoanaspo<<erIs~109XRatedThereatPa<<cr(TrtpSctpolnt) bytheNIS.ThisIsat<<aysthellntttngtripforatntsusfccdbaak, rapidrcaatlvlty lnsertton evcntc.fora>>xtcusfcccbaak, rapidreactivity tnscrtlan events,theprcssureceltrotsysteatsnotexpectedtokeepupthcrcbyalsoproducing

~highpressuredeviation clare.Ihestatreactivity Insertion eventsareexpectedtofillthcprcssurtzcr endpl'odua44LcvclelenaIhcescalation ofpwcrInarcascs Tavg,andVideRangeRCSTeaperature RecorderIndications are2

UNI'II2fSARTRANSIENT 0IA.I.2Icont'd)IRANSIEHI

'IRIP/SAFECUARO fUNCIIONFORRXTRIP(/SARII.lr'f)IHPACTOFCtseQNHCOEfAILUREICHf)ONTRIPFQICTICHALARH/ALTERNATE ILOICATION STSTEHAVAILARLE OIAGRAH4CONSEOUENCES OFUMAVAILASIL IITOFDIVERSE'LARH EVALUATION OFEVENIavallabl~tothepocratorIHesodatedp/2/p2froaU.O.SotostoV.O.Vandcrsurg),

prcssurlzcr Rxtripandhfohprcssurlzcr wtcrLevelRxtriphaveOlvcrseAtaresavallablc.

A.theCookUnitsarebaseloadedsothattheyoperateprlaarlly atIOOXRTP<<Ithrodscsscntlatly cosptetcty ulthdram.

TheLoverpouercasescsscntl~Ilyaddresscondltlona uhlcharetransitory.

Ourin9transltlon opcratlon, operators ulllgivecloseattention toIndlcatlonP astheynanlpulate thenarhlne.NatethatpoucrsVOXareusedoccaslonatty tostretchacycle.forthesereasonsthislsaIouprobablllty event..3.

UNIT1a2ISARfRANSIENT 4IC.1.31C.I.C'IRANSIENIRodClusterControlAsscebly(RCCA)NlcaLlgnacnt(IC.1.3)RCCAAssccblyDrop(TC.I.C)TRIP/SAFECUARD FUNCTIONfORRXTRIP(fSARIt(.I.3~It(.l.tfMoreactortriponRCCAa(sal(gtvcent (FSAR1C.1.3)forRCCAdroprod(s)event,theanalysisdocsnottakecreditforanydirectreactortripduetodroppedrods(UCAP-TI39C, pageI2)IHPACIOfCCHNOMHCOEFAILURE(CNF)ONTRIPFUNCTIONALARH/ALIERMATE INDICATIOM STSIBIAVAILARLE DIACRANgCONSEOUENCES OFUNAVAILADILITTOfDIVERSE'LARM EVALUATION OFEVENTforRCCAelsallgfvaent event(fSARIC.I3),therelsnoreactortrip.TheanalysisforRCCAdroprod(s)cvcntdocsnottakecreditforanydirectreactortripduetodroppedrods(Uchp-)139(,

paget-2).Thus,thercplaceeent ofcxlstlngM-Llneanalogprocessprotection systenullLnot~ffcctthefSARresultsofthesetuoevents.lhefattcuingdctectlon signals/slams are~vallsbleFortheoperatortorespondtothesetransients (FSAR,Unit2pages1C.1.3-1and1C.1.'3.2) t(I)SuddendroplncorepaverlevelasseenbytheNIS(II)Asyrnctric pouerdistribution asscenonout-of-core neutrondetectors orcoreexitthernocouple, (III)Roddeviation

~terat(Scf'point-Individual ralpositiondcvlatlon

+12stepsfraadeaandcanter,Procedure 2-ONPCORC.210Drop29),(Iv)RodpositionIndication.

Inaddition, forroddroppedeventordroppedbank,thcfullyInscrtcdassccblles areIndicated byarodatbottaasignai,uhich~ctwtcsacontrolroaaanntnciator (sctpolnt 20stepsfroathebettaa,Procedure R.ONPCORC.210, Drop22).

VNI'fI12fSARTRANSIEN'I gIC<'I.STRANSIENIUncontroclcd SaranOllucionIRIP/SAFEGUARDfVNCIIONfORRxTRIP(fsAR ici,l~5)1)llfthreactorlnaats<atcontrolsndnooperator~ctlontakentotcralnate thetransient, theFNwerard'cccpcra'cure

>>illcausethereactortoreachtheoverccsperature

<<I(oc<<T)tripsctpolntresulting In~reactortrip(fSAR,Page1(.1.$5)IHPACIOfC(secGNHOOEfAILURE(CHF)ONTRIPfVNCTIONOT<<1reactortriptost(accodated9/2/92frasMg.SotostoV.D.Vandergwg)

ALARH/ALTERNATE INDICATION STSIEHAVAILASLE h~<asI<dtcaNISpwcrrangeovcrpo>>cr rodstopat103XPr(sary>>ster fto>>deviation

~laraRoricandflewdeviation clara>>lth rodsincute>>aclacRodbankDLcw~laraRodbankDIou-LoualaraAmllbl~indication ofrodaoclonDIAGRAN4fg.2102Sheet3/CCONSEQUENCES OfUNAVAILASILIIT OfDIVERSE'LARH EVALUATION OFEVENTIhefSARscctlcnIC.I.Shascxsafncdthreephasesofborondilutionaccident, I.~.borondilutionduring(I)refueling, (II)startlp,snd(ill)poueroperation.

fordllutlonduringrefueling, thcrcarcaorsthan33afr<<tcsavailable foroperatoractiontroathetlaeofInitiation oftheeventtolossofshucdwnasrgln(SX<<k/k)(fSAR,page1(.1.5.$).Forrefueling cade<thecostLikelysourceofdilution, CVCS,lstaggedout.forotheraodcsthlcsourcelsnottaggedout.fordilutionduringstartlpthereareacrethan3Salnutcsavailable fortheoperatoractionfrc<athetlaeotInitiation ofthceventtolossotshucdounaargln(1.3Xik/k)(fSAR,pageIC.I.S.S) forUnit2<<dESala>>teatorUnit1.Startuplsatransient operation.

Opcratofs

>>lllgivecloseattention toIrdlcatlons astheyaanlpulate theaach\ne.DilutionaccidentatpeerIncludesthereactorInautoaatic controlol;aac<<a(control.tilththereactorincute>>etio control,thcpo>>erandtccperature IncreasefroacheborondilutionresultslnInsertion ofthecontroLrods<<dadecreaseIntheavailable shutdo<naargln.1hcreareacrethanCSair+teafroathctlaeof~Lara(LouIouredInsertion (lait)toLossofshutdo<<naargln(1.3X<<k/k)(fSAR,page1(.1.55)forUnit2andCgaf<v<tcsforVnlt1.theCookUnitsareoperated>>lthrodsinautasatlc untesstherels~cocpettlng reasontooperateInaanual.illthreactorIna<<smLcontrolandnooperator~ctlcntakentotcralnatc thetransient, thepwerandtcapcraturc

>>ouldcausechereactorcoreachDT<<Ttripsctpolnc.

Thistrip>>illbelostas~resultofco<<>>naodafailureottheneuFoxborodigitalsystca.Theborondilutiontr<<>>lentInthiscaseicessentially equivalent toancs>>ontroL(cd RCCA>>ithdrauaL atpoucr(fSAR,page1(.l.S-I).

ThereIsnocontrolrosaclarafrcathea'1aystcaforth'isevent.No>>ever,theincreasing pwerand>>lderangetcoperature Indications>>auld indicateconSIclons totheoperator.

Thiseventlsssto>>rcactlvicy additionevent~~Ipca/sec<

.5.

UNIIIa2ISARIRANSIINI 4lt1.5(con'I)IRANSIENI

)RIP/SAFECUARD FUNCIIONfORRXIRIP(fSARIt(.t.r)IHPACIOfCOHHONHCOEfAILURE(CHf)ONIRIPIUNCIIONALARH/AL'IERNAIE ILDICAIION SVSIEHAVAILASLE OIACRAHgCONSEOUENCES OfUNAVAILASILIIY OF0IVERSEALARHEVALUAIIONOFEVENFFollovingthediscusslonontneontrot lcdRCCAbankulthdraval atpower,thehighprcssurlzcr uatcrlevel~Laralsassumedave(labia, tblchhastuodiverse~Lanes(mesodated9/2/92fromM.o.sotostoV.O.Vandergurg).

)hislsastoutrans(cnt, andulththeprcssurhcr level,Nlderangetcoperaturc Indlsatlens,andotherIndlcatlons, theoperatorshouldbeabletotripthcreactor.

0ll UNIT'Ia2ISARTRANSIENt NI(.).6.ITRANSIEN'ILossofforcedReactorCoolantfla<<TRIP/SASECUARO (UNCTIONfORRXTRIP(fSAR(IIIgI)1.Rxtriponreactorcoolantpappwerslppiytedcrvoltage orunderIrccpcnay2.RxtriponLa<<reactor coolantloopf1o<<.IHPACIOfCOHHONHOOfIAILURE(CHf)ONIRII'UNCTIONNotAffectedLo<<flo<<RxtripLost(for~LLfourloops)ALARH/ALTERNATE INDICATION STSTEHAVAILASLE ReactorCoolantPulpunderfrecpcnay andIJndcrvaltagt alafsl(Procedure I,2-oxp,(02(,107,207)I4IonAvsIabPanelInd(catIoncooputcrindIcatIonvcrAlaraAvalcbta~hPress<<riser prcssurepanelIndication Prcssurlzcr prcssurercaordcrPrcssurltcr pressurecocpulcrIndication Prcssurlter levelpanelIndication Press<<riser levcLrecorderPrcssurlter LevelcoeputcrIndication tilderangetccpcrature recordsQhhr~cPrcsswiterhighprcssuredeviation vl~controlayctcQfourhighpressure~LarsiviacontroLsystoaPrcssurltcr highleveldeviation viacantrolcyst<<aNighlevelviacontrolsystuaAcousticNanltorfloudctcatcdDIACRANgID2101Sheet3and(CDNSECUEMCES OfUXAVAILASILIIT OfDIVERSEALARHIftheRxisatpo<<cr4tthctineoftht~aaldcnt,theimacdiatc effectof~lossofcoolantfia<<la~rapidIncreasetnthecoolanttcopcr4'turc

<<blahIs~ugnlfledby~positiveHTC.IbisIncreasecouldrcsuttlnDNS<<lthsubsequent advcrsccffcctstothefueL,iftheRxlsnottrippedprocptly.

((SAR,pageI(.).6-1)

EVALUATION OfEVENTIhcRxtripanreactorcoolantpulppa<<crslpplyundcrvoltage andunderfrequency rcaainclalallcatcd byaaaaoonNodefailure(cxf)ofthene<<digital Instrloentat ion.ThereactortriponLossoff(a<<ln~coolantlooplslostonCHffortachloop.ThesearenoDiverseAlarmsavallablcl ha<<ever,panelIndite'tlon andcocputcrIndlca'tlon art4vallablc fortheLa<<coolantloopflow.T<<ocasesoflossofflo<<arediscussed lnfSAR(I(1.6).Iheslcultsncous lossofpeertoallCRCPscanoccurduetoeitherundcrfrcqucnoy orundervoltage,

<<hlchIsnotlcpaatcdbyCHF.'Ibissituation Ishighlymllkely,sino>>eachIxapIscarncctcd toaseparatebus,<<blahlsstpp(lcdbyancoft<<otransfonacrs.

theconsequences ofthelossofflouInaiufeanIncreaseInTavg,pressurlter

pressure, andprcssurlter

<<sterlcvcl.ViderangeRCStcapcrature recorders (necodated9/2/92froaU.C.SotostoV.D.Vandergurg) areavailable totheoperatortoindicateanIncreaseInTavg.ThcrcIsnoRxtriponhighIavg.Thcprcssurlter prcssure<<illcontltwetoriseuntlLthcoperatorgets4highpressuredeviation slaneet2325pais(2.ONP(02(.200Drop7)forUnit2and2175pslaforUnit1.theRxtriponhighpresswe(cctpolnt

<<2(00pale)lsLostduetoCHf.However,dlverst~Lares(octodated9/2/92franM.C.SotoatoV.D.Vandergwg) areavailable.

Itlscvldentthatthehighprcssuredeviation alarm<<ILLdrauthaoperator'a attention, andhe<<ILLtriptheRx<<atua(Ly.

Thcoperator<<IILalsobeLikelytoseethehighleveldeviation

~LareatSXaboveprograa.Thccansapcnocs ofthlcNanualRxtriparedlscussedbclou.Crudecxtrapolat ionaofDNSRfortheattvcntasuggestthatIONSRcouldbereached<<lthln.16towigsecondsforlossoffLo<<lnoneloop.Siai(arextrapolations suggestthatthehighpressuredeviation elena<<auldfirstbereceivedWsecondsintothetransient

~Lthoughtheoperation ofpressurltcr sprays<<ILLIncreasethiscstlaate.

Allo<<tng~scaandsforoperation responseItisclearthatDNScould.7.

0 UNITI2ISARIRANSIENT 8It.t.6.1(cont'd)TRANSIENT TRIP/SAFEGUARD FUNCTIONFORRXTRIP(FEAR IHPACTOfCOHHONHCOEfAILURE(CHf)ONTRIPfUNCTIONALARH/ALTERNATE INOICAllOI STSIENAVAILARLE DIAGRANgCONSEQUENCES OFUNAVAILASILITT OFDIVERSEALARHEVALUATIOI OfEVENToccurresulting Inclatdanagc.Since~nasstve~ultlplefailurelaaccusedforthisevent,thfslcbelicvcdtobeacceptable.

lllth~lossofflowtnonelooptotalcoreflowshouldrcnalnrooovlngthebulkofthcheatfranth<<core,Ltatttngthedeterioration ofthecorepriortocenualreactortrip.Theportionofthecorethatcxpcrtcnccs ONSlsexpectedtoheatuptntlttheDopplercoctflcfcnt shutsItdown.FuelIsnotexpectedtosettbutctadburstandoxtdatlon areanticipated.

Ltshouldalsobenotedthatthiseventwasanalyzedwithapositiveaedcratlon coefftctcnt (NIC)ofeSpaa/'F.IhlsvaluelsnoreLlatttngthantheTcchnlcat Spcctflcatton Licitat100XRTP.Itfsconservative andprovidessMtantlat chargtnthroughout nestoftheLife.cthtscausespowertoIncreaseasthecoolanttccperature Increases.

Anorercallstlc asstnpttcn forbeginning ofcycleIc-(pcn/of.

AnegativeNICwlLLtendtoshutdownthecoreestccpcraturc increases ntttgattng thecvcnt.theHTCbcconcssdstantt~Ltynorenegativeashurrayprogresses.

TheCookUnitsarebaseloadedandoperatewithcontrolrodsinthealloutposltlcnatfuttpower.There(orc, theposslblltty thatcutcnatlc rodcontrolnightulthdraurodswILLhavenolcpactbecauserodsarcessentially fullywlthdram.

Afterreactortrip,thececrgcncy operating procedures providefornlttgatton activities tobringthecjachlne'toesafecordlttcn.

Intheevaluation ofthepreviousparagraph, anoperatorresponsetineofMsecondsuasassuacd.Mtthoutereactortrip,prcssurltcr assureanflevcLareexpectedtoconttrwctoncrcaseafterthefirstatomsareresolved.

Shenprcssurereaches2250Dalai'thePORVicwillopenrcsultlng lnanacousttceonttorftoudetectedstars.Extrapolating theanalysiscurves,whichdonotcxdctprcssurltcr spray,thiscouldoccurbeforeIINSRlsreached.Therefore, itlsLikelythatanecctnutatlon ofeternewiltoccurbefore60secondshaveelapsed.Therefore, theopcratorc responseticenaybelessthan40secondsforthisevent.

UNITI2fSARIRANSIENI IIS.T.S.IIcont'd)TRANSIENT TRIP/SAfEQJAAO fUNCfIONfORRXTRIP(ISAR)tt.f.g.t)

INPAct0FCQONNINCOEFAILUREICNF)ONTRIPfUNCTIONALARH/ALTERNATE INOICATION STSTENAVAILABLE DIACRANNCONSEQUENCES OFUNAYAILABILITT OFDIVERSEALARMEVALUATION OFEVENT,,TheeastIlkclycauseofeneventofthist)pc,lsafailureofthereactorcoolantIanpIRCp)orItsactor.Thcoperatorlsprovidedulth~slsnlfleantrasherofeternetogivehfninforoatlon resardlnS thcRCP'sandenters.These~TarosIncludeRCPactordlffcrcntlal trip,RCPactoroverloadtrip,sndRCPaeteroverheated.

Therefore, ItIslikelythattheoperatorNlllhaveInforaatlon available shishNlllatlouhietoantlclpatc

<<d,therefore, substantially nltlgatetheevent.

UNIII2fSARTRANSIENT 4IL.I.6.2IRANSIENILockedRotor/She ftBrcakAccidentTRIP/SAFECUAZO fUNCIIQIfORRXIRIP(/SARLLI,Lofe2)ReactortriponLo<<flo<<signalIHPACIOfCttetOHHCOEFAILURE(CHF)CHTRIPIUNCTIONLo<<fto<<reactor tripLost(acao9/2/92acaofretsV.C.SotostoV.0.Vctdcrgwg)

ALARH/ALTERNATE INOICATICttSTSIEHAVAILABLE tdleelsAvclchPanelndicationCocputcrIndication vAraAvcCMc~h~l~aens Pressurizer prcssurepanelindicatIonPressurizer prcssurerecorderPressurizer prcssurecocputcrItdicatlon Pressurizer levelpanel(Cd(cation PrcssurizcrLevelrecorderPressurizer levelcocputcrltdlcatIonViderangetccperature recordsgourdolprcssurlzcr safetyvalves9~het~ccPressurlterhighprcssuredcvlatlon viacontrolsystcclfourhighprcssurealarsaviecontroLsystctaPressurizer h(ghLeveldeviation viecontcoi4ystuaNighlcvcLvscontrol4ysteaAcousticaonitorfLoudetected0IACRAHNf0.2101Sheet3and6CONSEOUENCES OfUNAVAILABILIII OFDIVERSEALARHLftheRxlsatpateratthctlaeof~ccldcnt,theIctscdiatc effectof~loss.offto<<(seizureof~RCProtor)lsanincreaseInthecoolanttccperature.

ThisIncreasecouldresultInONB<<lthstftscqucnt adverseeffectstofust,iftheRxIcnottrippedprocptly(FSAR,PageIL.I.6.1)

EVALUATION OfEVENTThcfSARanalysisfoc'thiscvcntassuscsan!nstentcncous seizureof~reactorcoolantputprotor.Forthisevent,thereactortripsonlo<<fle<<signal.

'thecotcsonaodefailure(CHF)ofthene<<digital Instcttscntat Ion<<outdresultIn~lossoflo<<flo<<gxtripsignal.Ihclossoffle<<<<illIncreasethecoolanttccpcraturc atdanIncreaseInprcsswlzer prcssuredueto~reduction lnbeatrcaovat.The<<lderangeRCStccpcraturc recorders (accodated9/2/92freeV.O.SotostoV.0.Vatdergurg) arcavailable tothcoperator.

Theprcssurlzcr prcssure<<illcontinuetorise,endtbaoperator<<illgct~highprcssurlzcr deviation

~Iaraat2325paid(Procedure 2-ONP(02(.200Orop7)forUnit2attd2175ps(aforUnit1.Thereactortriponhighprcssure(<<2(00paid~)lslostduetoCHf.No<<ever,highprcssurediverse~Iarstsarcavailable (acctodated9/2/92froaV.O.SotostoV.0.Vandergurg).

Therefore, thehighprcssuredeviation clara<<illdra<<thcoperator's attention totripthereactorttatstaiiy.

IbiseventlsverysztdtLikethclossofforcedreactorcoolantfle<<incnetocp.No<<ever,ltlscoresevereInthattotaLcoreflatlacc4Kcdstorerapidly'to~Lo<<ccvalue,thetotalcorefloulsreducedto7OX<<Ith(n~'2accords.Asthecoolantheatstp,asignificant IrncaseInprcssureoccurs.'IhepeakanalyzedprcssureforbothmitslaM90psla.Ibispeakoccurredat2accordsafterthereactortripat1accord.IbisprcssureIclessthan110Xofthedesignprcssure, I.~.2750psl~.No<<ever,lfreactortriplsdelayed40sccotds,itcarrtotbestated<<lthcertainty thatthisprcssure<<outdnotbeexceeded.

No<<ever,the~nalyslstakesnocreditforpressurizer sprayorthcpressurizer PORVts.Ltlsalsothecaseas<<lththeLossofforcedreactorcoolantfle<<thatthaanalysis<<44pcrfoctacd

<<lth4po4ltlva~todcrator tccperature coefficient (KIC)ofc5pca/'f.ThisvalueIscoraIlaltlngthanthe'Tcchnical SpeclfIcationI\altatIOOXRIP.Ltlsconservative andprovidesstftstsntfal aarglnthroughout thacoreLife..10-~~~"~~Q0tmhct~'tr>.<~<4...:">~-.....I~,.""~m.,impC~.)..."3~~F.'tr..aC ONITI2fSARTRANSIENT NIS.IA.2(ccn't)TRANSIENI TRIP/SAFEQJARO fuKCTICNfORRXTRIP(CESAR(tf~t~ga2)INPACTOfCISOQNINIOEFAILUREICNF)OITRIPfOKCTIONALARM/ALIERNATE IKOICATION STSIENAVAILASLE 0IAGRANgCONSEQUENCES OFLNAVAILASIL ITTOf0IVERSEALARNEVALUATION OfEVENIThcrctore, asTavgIsfncreascd, powrIncreases Intheanalysis.

AsIndicated Inthelossotforcedreactorcoolantftou,~sorercatistlc beginning ofcycleNTC,uouldbe~-Spec/~F.

throughout corelifetheNTCuoutddecreasetothc20pcn/'F.

ThefccchackfreaktheNTCuoutdtherefore tendtoshutthereactordounratherthanIncreasepavertnanactwlevent.IheCook>nitsarcbaseloadedandoperateKithcontrolroCkIntheatloutpositionatfulLpoucr.thepossibility thatautocotic rodcontrolnightutthdraurodsuttthavenotcpactbecauseroCksreessentially fullyutthdraw.

Theseconsiderations toadustoconcludethatItlstntlketythatprcssurltcr pressureuoutdexceed2730pslaandvirtually tcposslble toexceed3200pstIF,theARNERollerhandPrcssureVesselCodeLevelCcrlterlcn, uhlchuasusedforANSACdesign.Intheanalysts, ONStsexpectedtooccur.Intheeventofadelay,.ot reactortripby~seconds,thissituation canonlybeexacerbated.

Theoperation ofpressurltcr spraysandPORV'suhlchverenotsedatedIntheanalystsutttalsoresultInanIncreaseInfucLrodslnDNS.Nouever,ItIsbelievedthattheavailable ftouutilpreventthecoretrondegrading tocondition uhereItcanrotbecooledaftertrip.Theportionofthecorethatcxpericnccs ONSlsexpectedtoheatuptnttttheOopplcrcoefficient shutsttdoun.Fwllsnotexpectedtonettbutcladburstandoxidation areanticipated.

Qbstantta\

coredaoageIs~cccptabte forthtscvcntKhtchlsanANScondltton IVcvcntKithsuasiveaulttptefailures.

Intheevaluation ottheprcvloustuoparagraphs, anoperatorresponsetineof~cecondsuasaksuaed.Nowvcr,thiscvcntlsexpectedtobeverydracetlcSeveralprcksurltcr atarkxtcanbeexpectedNlthlnsecondsofthestartoftheeventIncluding theacousticcxnltorfloudetectedslane.'theprcskurttcr cafctyvalvescanbe<<xpectcdtoLiftuhtchcreatesantcprcsslve soundinthecontrolrook.Therefore, theoperators responsenaybslessthan40secondsforthiscvcnt.

J':~~~P4lt4,"tgq'IA

~~~~~~I\I0~I~~I~~I~~

UNIT'I2ISARTRANSIENT

~It.).7TRANSIENT Start>@ofanInactiveReactorCoolantLoopIRIP/SAFEGUARDFUNCTIONFORRXTRIP(<SARIt(.I.2)Unit1andUnit2operation duringstartupandpoveroperation ulthlessthanfourtoopslsnotpcrnlttcd (I/S3/(.(.I)exceptforspeal~ItestingasprovidedforInI/S3/(.10.5forUnit1andI/S3.C.IO.SforUnit2.LicenseccndltiaraforbothUnitsprohibitoperation aboveP-7ulthLessthanfourreactorcoolantFcnpslnoperation.

Noucvcr,thcUfs*RcontainsanalyticofthiseventforbothUnits.ThisinforoationlaprovidedforInforoatlon andbecauseItboundsthetestcondltlcns Inslcatcd above.!haseanalysesresultInreactortripsonnuclearInstruscntatfon hfghf(ux.INPACTOfCOHHONHCOEfAILURE(CNF)ONTRIPFUNCTIONALARM/ALTERNATE INOICATICN STSTEIIAVAILASLE DIAGRAMNCONSEOUENCES OfUNAVAILABILITT OfDIVERSEALARNEVALUATION OfEVENTInaccordance ulthT/S3/SA.T,operation duringstart~andpoucroperation ulthlessthanfourloopslsnotpernltted.Assuch,thisaccidentuasnotanalyzedfortheVANTACE-5 fueltransition (Unit2FRAR,pageI(.1.2-1) orfortheUnit1reducedtccpcrature andpressureprograa(UnitIUFSAR,Page1(.1.7-3).

Tbcrcfore, thecocnonnodefailure(CNF)ofthencufoxborodlgltaLsystnsuouldhavenolcpactonthistransient.

'-13 0V UNI)I2ISARTRANSIENT NI(~1.0IRANSIENI LossofExternalElcctrlcLoadorTurbineTrip(fullVantage.S Core)TRIP/SAFECUARD FUNCTIONfORRXTRIP(FSAR)CI)Reactortripsonfotlouing signalsx1.Nighprcssurlzcr prcsswesignal2.Nighprcssurlzcr uatcrlcvcl3.Ovcrtceperature at(OTit)signalInphcfofcotcoNncoEfAILURE(CNF)OlTRIPfUNCTIONNighprcssweRxtriplostNighprcssur1teruatcrlcvcLRxtriplost04TRxtriplostALARH/ALTERNATE IAOICATIONSTSTENAVAILABLE IcAvaab~PanelndlcatIon~Panelrecordercocputac'Indlcacicn vrAaresAva'Iablt~NghPrcssuredcviaticn vl~.controlsystcca~Nighprcssureviacontrolsystce(four~lares>~Pressurizer PCRVdischarge tccphigh~Prcssurlzcr safetyvalvedischarge Cccphl(3~Lares)-Pressurizer relic(tankCccphi~Pressurizer relieftankpressurehighorLou.Prcssurlzcr relieftanklevelhighorlou~Acousticeonltor(loudetectedcd~Aveabl~Panelted(cation

~Panelrccordcr-Cocputcr Indication avaebtsetpolntviecontroLsysCeo-Pressurizer levelhighfroacontroLsystccaViderangeRcscccpcracure recorders OIAGRAHgFD2101SheetI/dF0-2101Sheet2/0FD2IOISheetSCONSEOUENCES OfUNAVAILABILITY OFDIVERSEALARNEVALUATION gfEVENTocsooadTwbnoTIThccostIkctysourceofacocpt~caLossofloadInNSSSIsatripofthetwblne-generator or~differential relayuhlchresultsIn~turbinetrip.InChiccase,therels~directreactortripsignal(crclcsspowerlsbetou~pproxleatcly 1'lXpovcr,I.e.,betouP.T)dcrlvcdfreestheturbineeacrgency tripfluidprcssureandturbinestopvalws(FEAR,pageT(.T.SS-I).Ihercfore, thecoccacnnodefalture(CNF)ofthencudigitalsystcehasnoIcpactonthereactortrip.sofLoadulthouwbiITuoInitiating scenarios sereconsidered forthiseventsCocptetelossof~lcctrlcal Load,~ndlossofcondcnscr vaccxec.e Itoecrcaoadforthiscvcntthereactortripsonfourtripfca>>tfcns.

Forhighpressurizer prcssuretripfcz>>cfcn, threealternate Irdlcatlons acdseveraldlvtrst~Iaresareavailable.

forhighprcssurlzcr taterleveltrip,threealternate Irdfcatlons andtuodiverseclareavailable forIou-Lousteangenerator uaterlcwltrip,threealternate Indications acdoncdiverse~lanaareavailable.

TheseIrdlcttlons, stares,~ndothertndlcatfons, especially thcscxsdofsafetyvalvesshouldprovfdeIcdlcatfons totheoperatorofabnonaalcltwtionandhtuouidtripthereactoreacxcaliy.

The(spaceofthccoccacnnodefailure(cNF)ofthedigitalsyscceuouldresultIn~lossofOfatreactortripfcc>>Clan.

ThtOtitreactortriplsthtonlyfcz>>ttonforwhichthe~Iternatestares/lcdicatlcns arenoCavallabl~thelossofreactortripuouldcausetheRCSprcssureandtccperature torise.Thisuouldresultinantncrcaseofpressurizer uacerLcwl.Prcssurlxtr

pressure, prcssurlzcr Level~ndulderangetccperature Indications ara~vallabl~cotheoperatortotripthereactor(eseodated9/2/92freesU.0SotostoV,0,Vandergurg).

Thehighpressuredeviation stareactivafts at232$psia(proctdwe 2DNP(02(.208

fSARTRANSIENT gIL.I.O(ccn't)IRANSIENITRIP/SAFEGUARD fUKCTIONfORRXTRIP(fSARIfI8)4.Lou.fousteangawratoruatcrlevelIKPACTOfCOtOKNIHCOEfAILURE(CHf)OKTRIPfUxctIDNLo-LoHaterlcveLreactortrtplostUHI'fIandI2ALARK/ALTERNATE IKOICAIIOH STSTEHAVAILASLE

~Ava~Puwtndlcaton~Panelrecorder~cocputerindication

~vaabl'LcvcLdeviation v~controLsystoathcctonsAarea~PaverRangeovcrpoucr RodStop~Sourdofsteangenerator andprcssurltcr safeties.

~Audibletrdlectionofcontrolrodaction.OIACRAKgCOKSECUEKCES OfUHAVAILASILITT OfDIVERSEALARHEVALUATION OFEVENT~",Dropy)forUnit2and2175forUnit1.Thisalcfnuouiddrauoperators attcn'Lion Prcssurltcr spraysuoutdbegintoopenat2260pslganduouldbefulLopenat2310pslg(FSAR,Table4.1.2)forUnit2andfran2110pslgto2160forUnit1.1hePORVNILIbefullopenat2355palg,sndsafetyvalvesopenat2405pslg(fSAR,Table4.1-2).Assuslngthcavailability ofthiscontrolcquipacnt, thcprfeeryprcssureshouldnotcxce<<d2750palafnthentnlsxaareactivity fcehsckcase.1hcHTCforthiscaseicaccusedtobec5pca/'FandtheDopplercocfftclent ls~saucedtobe~.6pcn/X.

Korerealistic

~ssoptionsforbeginning ofcycleandNipareHTCa-(pcn/XandDoppler.Open/X.thesevaluesutilIncreasethctccperature fecchsckrelativetotheanalyslctendingtoreducepoucrandconsequent lyprfnaryprcssure.

Intheaexlaxsareactivity fcogwck,thereactorpaverardconsequently prfaaryprcssureerereducedbythernalfeedback.

OHSRtanotthreatened Intheaaxtcxaareactivity fatbackcase,Additional controLequipncntnayalsooperatetoalttgatcthlccvcnt.ThepoucratsawtchchannelforrodcontrolcanbecxpectcdtooperateonalossofLoaddrivingrodsintothecore.Thetfcwccnstantoffirststageprcssuretc40scc.Therefore, rodscanbeexpectedtoinserttntittheoperatorInitiates protective actlcn.IfTavgfatlcconstantonacHForfallshigh,rodsKillccntfnuetoinsertafterthepavernlsaatchsignethasdecayed.'thestean&aytocardcnser ucutdalsoSperateKithtavgconstantorhighprovtdcdthatcondcnscr vacwaoroffsltepaverarenotlost.0rVthelossofcondcnscr vaaasaaffectsonlytheturbineandnotthereactorprotection systoa.Therefore theturbinetriponccndcnser vacuaKillresultIn~reactortripsincebothrccwtntawffccted bythecocoonaxdefatlureofthencudigitalsystce15'AP

UNLII2FSAR1RANSIENI g1C.1.9TRANSIENT LossofNormalFCCdv4ICI'RIP/SAFECUARD FUNCTIONfORRXTRIP(FSARLti,IQ)1.ReactortriponLou.touuatcrlcvclInanystcamgenerator 2.ReactortripcnLoutccduatcr tlousignalInanystcamgenerator (Ihlcsignalls4ctually~stc<<4floufc<<heater mismatchIncoincidence ulthlouwterlcvcL)3.Tuosecordrivenauxiliary fccduater FcmpsIfclchare~tartcdcnt~.Lou-LoulcvclInenystcamgcncratol'.

Tripof~Llmafnfccchcatcr c.AnysafetyIn)ection signalb.Ckvbuslossofvoltage~.Nanualactuation Ctufb'lnodflvcn4uxILIary fccduatcr pufplsstartedonta.Lou-IouLevelInanytuostcamgenerators b.ReactorcoolantfxmpbwIxvtcrvoi tsgeIHPACfOFCCNNCNNCOEFAllURE(CNF)ONTRIPfUNC'lION(carlouleveltriplostLoufc<<AIatcr floutriplostIOAFPstar'ts(Outocotfc Initiation) onLou-Lousteangenerator levcLOndsafetyin]ection fromnnn-manualInitiation areLostTDAfPstart(autcmatlc Initiation) onLou-Lou"stcamgenerator levelIslostALARN/ALTERNATE INDICATION STSTOIAVAILASlE vcf4~Avaab~stcamgenerator leveldeviation viaccntrolsystemAY4ab4~Panelndcaton~Panelrecorder~cocputcrIndication saneasabove(forstcamgenerator lou.louwtcrlevel)sameas4bovasamacaabovehrAfatand~~Prcssurltcr highlevcLdeviation

~Prcssurlter levelhighDIAGRANgFD.2101Shcct5CONSEQUENCES OfUNAVAILASILLTT OFDIVERSEALARNEVALUATIDN OFEVENTTheccxononmodefailure(CNF)ofthencudigitalcqulpmcnt resultsIn4Lossofreactortripsonlou.touuatcrlevel,andonLoufccckatcr flousignal(stcamflou/fccdtlou mismatchIncoincidence ulthlouuatcrLevel).goththemotordrivenOcafturbinedrivenauxiliary fc<<heater SystccaaarealsolostexceptInsituation described betou.Themotordrivenauxiliary fccduatcr tempsarenotaffectedbyCNFIftheScopestartedonCkvbuslossofvoltageorLossofallmainfceduatcr pcmps(1/Stable3.3.3,pago3/C3.19).Theturbinedrivenauxiliary fccduater FcmplsalsonotsftcctedbyCNFIfthepcmplsstartedonreactorcoolantFxafpbuscedcrvoltage (1/STable3.3-3,page3/C3-2g).lncaaeOftheCNFofncudigitalequipment, 4'tc4algcncfatol'evel deviation

~LacaaandANsAC~lenaareavallabl~totheoperator.

In~ddltlon,threealternate Indlcatlcns aro~Lsoavailabl~.fortheLossofnormaltc<<heater/ATUS transient, ATVSNltlgatlng SystemActuation Circuitry (ANSAC)lsavailable (memodated10/13/92frccaV.0.SotostoV.0.Vandergurg).

theANSAC~utccaatfcaLLy lnftlatcs

~turbinetripandInitfatcs AFVfloutomaintaintheRCSprcssurebclou3200pslg(ASNERollerandPrcssureVesselCodeLevelCcriterion).

At100XRIPthesefceotfona areinitiated at30scc.oftranstcnt signaLdelaytlm4ANSAClaOVallable

'toperformthisfcectlonInthceventtheCNFotthencudigitalequipment occurs.AnJNSAC~Ivxecfator lsinitiated afterANSAClsactuated(Proccdwo 2.ONPC02C.212DrcpTC).ThetufbfnetripIsnotaffectedbytheCNFofthencudigitalcquipmcnt (memodated9/2/92freeV.0.SotostoV.D.Vandcrgwg).

Therefore, thereactoruouldbotrippedIgxnnturbinetrip.AtaLLpoucrsthestcamgcncratOr leveldeviation alarm,prcssurfzcr levelhighLeveldeviation andprcssurlxcr levelhighare~vallabletoalertthcoperatorto4LossofnormaLfccduatcr event.Inaddltlcn, Ixaacrous

~termsdescribing thcstatusotthecondensate andtccduatcr systemsandpcmps,suchesccedcnscr hotuctIlevel,boostermatertrip,IS~

U<<lfI2fSARTRANSIE<<1

!LL.I.9(con't)TRANSIENT TRIP/SAfEQlARD FUNCTIONfORRX'TRIP(tSARLg.t.q)IHPACTOFCCHHCHHODEfAILUREICHF)ONTRIPFUNCTIONALARH/AL'IERNATE INDICATIOH STSTEHAVAILABLE DIACRAH0CONSEOUENCES OfUNAVAILABILIT'f OfDIVERSEALARHEVAlUATIDH OFEVENtaalnfeed<<ster Fcnp,ctc.<<ILLactfvate.

Relo<<LOCratedtheraalpo<<cr,ItIsexpectedthatthesealaras<<auldleadthcoperatortotripthereactora<<cattyduetoLcuetcaeRcncretor lcvctInacfordance

<<lth2-ONPCD23.E-O.

Ueatsonotethatthiseventprogresses rclatlvely stcutysothattheprcssurlzcr fillsfnthcorderofalrutcsnotseconds.Thecvcnt~sdcscrlbed IntheUFSARlsanalyzedustngAFUfleabasedonf1o<<rctentlon.

Theoperator<<ILLbeabletoopentheflo<<rctcntlon valvestosubstantfalty Increasefccdvatcr fto<<.Itisalsonotconstdercd necessary toassueeanAFUputpfall<<reIneddttIontoCHF.Assuslnothe~vallabllfty of~LLthreeAflffsapsalsosubstsntf attyIncreases thcflouofAfll.forallthesereasons,<<ebelfcve'fheoutcoaeofthiscvcnt<<iltnotbestzatanttatty dlffercnt frcatheanalyzedresult.

UNITI2ISARTRANSIENT gL(.1.10.1 IC.I~10.2TRANSIENI Excessive ScatRcaovalductofccduatcr SystcaHalfcccotlons fccduater SystcaHalflectlenscausingandIncreaselnfccdustcr flowTRIP/SAfECUARD IUNCTICNfORRXTRIP(fSARLc(~IIo)I.Nighncutrcnfluxtrip2.Ovcrcccperature il(OI~I)tripOvcrpoucr OT(OPil)Crlpd.Sccaagenerator uaccrLevelhigh.high IHPACIOfCOHHONHCOEfAILURE(CHf)ONTRIPfUNCTIONNotsffastedofilreactortripLostopalreactortr'lplostLostALARH/AL'TERNA IEINDICATION STSIDlAVAILASLE NISpwcrrangeoverpovcrrodstopac103XclaraMlderangetccpcraturc recorders Mlderangetccperacurc recorders cacncAvslabia~Pane(ndlostfon

~Panelrecorder~Cocletcr Irldlcatlon

'~Aveltab~Leveldeviation viacontroLcystcaDIACRAHSCCNSEOUENCES OfUNAVAILAS'ILI'I'I OfDIVERSEALARHEVALUATION OfEVENIthereactortriponNISovcrpcwer sctpolntlsnotaffectedbythecoocaonaodefailure(CHf)ofthencudig(eelcqulpacnt.

IheOliTandopifreactortripserclostduetoCNIofthencudigitalequipacnt.Noaltcrnatc afarcaareavailable forthesetripfcNotfons.

Noucvcr,Hiderangehotandcoldlegccepcreture Indications areavailable.

IhccasesofIouprcssureorhighprcssurefccduatcr heaterbypassvalvefullyopen'lngrcsu'ltlntransients veryslallsrtothoseforcxccsslve IncreaseInsecondary sccaaflou.Thistransfcnt lsdiscussed Insection1(.1.11.TheUnit2fccchcatcr eventsarcboundedbythecxccsslve loadincrease.

IheUnitIcvcntsarealsoexpectedCobebounded.~foranIncreaselnfceduaccr flouIncheabsenceotCHf,cheturbineuouldtriponhigh-hfgh stcaagenerator uatcrLcvcl,uhlchweldtnturntripthcreactor.IncaseofCHf,thistripIslost(T/5Table3.3-3).Atceropwcr,steaagenerator lcvcllsunderaanuslcontrol.Therefore, theoperatoruou(dbecxpcctcdtoidentifytheeventprocptlyandtakecorrcc)fve action.SciouP10,theNIShighfluxsctpolntac2SXRTPandtheNISfntcracdiate rangetripsarealsoavailable.

AcIOOXRTP,thesceaagcncrator deviation clara(Procedure 2ONP(02L.213Drop2)uouldactivate~tSXaboveprogrscacd levelof(CX.Threestcaagenerator 1cwlindications ercavailable (acaodated10/13/92froaM.0.SotostoV.D.Vandcrgurg).

Inaddition, pwcrrangecwcrpoucr rodatopclara(Procedure 2-ONP(02(.210Drop19)uoucdactuateat10)Xpaver,uhfchuouldoccuracabout20scc.Intothecrsnslcnt (lCAp-12901~fig10.dlA)Mlththe5,0,dcvlatlon claraandlevelIndications available, theoperacorshouldbeabletotriptheturbine,~Reichtnturnuoufdtripthereactor.figurc10.1dAofICAP-12901 shousChat,thepwerstabltleesatspproxlaatcly IOSXnoainal(tripsctpolntel09X).

froafigure10.29AofLCAP-12901, thesteaagenerator devlaclcn a(alauouldaotuaceatabout0scc.Intothetransient.

Id

%.~UxllI11tISLAIRAH$IEHIIt.l.Io.tleant'd}L ItaxSIExt IIRIP/SASICUARD IUNCIIONICRRXIRIP(SCAR

)LI.)~LO)IHPACIOfCCHHCWHCOEfAllURECCHI}ONIRIPfUXCIIDIALARNlALIESNAIE IHOICAIION SfSIENAVAILARLE DIACRAN4coxSEOUExcf sofUMAVAILASIL111 Of'IVERSE ALARNEVALUAIION OfEVENI.Accusing theoperator's respcnsetinetobe60scc.,theturb}nowouldtripatcpproxlactely 60scc.'rthereactortriptfoclsapproaloatcty 70scc.flSurcsIC.1.10A-t and14.1.10A6oftheUnittUfSARshouthattheDkSRstthisticeisapproxfaatcty

$.6.flsures1C.1.10-t crvfIC.1.10-C shouDxttatthisticetobe.l.O.lhasavaluesarewellabovetheDNSRsafetyLlaltsforbothUnits.Ihcrcfore, therewouldnotbeanyfueLdaoasc.19 UNlf'IafSARIRANSIENI gIL.I.IIIRANSIENT Excessive loadIncreaseIncidentIRIP/SAfEGUARD FUNCIIOHfORRXTRIP(fSARIttItt)l.Ovcrpo<<er it(OPit)trip2.Overtccperature it(Olit)trip3.PaarrangehighneutronftuxL.Lo<<prcssur IacrprcssuretripIHPACTOFCO<<NOHHCOEFAILURE(CHF)ONTRIPIUNCTIONOPitRxTripLost(<<ceodated10/13/92frosM.0.SotostoV.Vandergurg)

OtalRx1rlpLost(<<ceodated10/13/92franM.6.SotostoV.Vandergurg)

NotAffcctcdLos!(nanodated10/13/92fr<<sM.0.SotostoV.Vandergurg)

ALARH/AL'TERNATE INDICATION SYSTENAVAILASLE MiderangeRCStccperature recorder'ide rangeRCStcepcreture recorderNISpaverrangeovcrpo<<er rodstopndlacnaAvalabl~PanelIndication

~Panelrecorder~CocputcrIrdlcationeAlaAvalab~Prcssurtscr Io<<prcssuredeviation (turnonbackuphcatcrs)viacontrolsystcshrvendlcaIAudbl~ndicatlon ofrodsationbelo<<103X.

Prcssurtzer to<<leveldeviation

~tarnPress<<riser Io<<level~tcrnDIAGRANgf0.2101SheetICONSEQUENCES OfUNAVAILARILITT OfDIVERSEALARHEVALUAIIOHOFEVENTIhacocooncodefailure(CHF)ofthenc<<digital cqulpscnt resultsln~lossofOPiTtrip,Otittripandlo<<prcssurltcr prcssuretrip.Thereactortriponpo<<crrangehtghneutronfluxIsnotaffectedbythcCHFofthereactorprocessequipsent.IheFSARsectionIG.I.IIhasccnsldcrcd fourcasestoanatyzcthiscvcnt(I)ReactorcontrolIncjsnwt<<lthnlnisssssoderator reactivity feedback; (II)ReactorcontrolInnanuat<<lthnaxlssssaodcrator reactivity

feedback, ttll)Reactorccntrotinwtocattc<<lth<<In!cessaoderator reactivity fcccback; and(Iv)ReactorcontrolInautoeatic

<<tthsaxlssssaNderator reactivity fccchsck.

Thareactortripand/orengineered cafcguard

~ctuatlcnsfgnal<<asnotgenerated forthtsevent(fSAR,pageIL.I.IIA.3).

TheFSAR~nalysisass<<assthatnonaatoperating procedures

<<outdbefolio<<cdtoto<<crpo<<er.Inthceventthatthiseventoccursconcurrently

<<Ith~CNfofthene<<digital reactorprocessequipaent, theoperator<<outdbeexpectedtobringthereactortohotshutdo<<nconsistent

<<lthT.S.3.0.320-1w

~~'~~'~~~~\'l~'

LNIII2fSARTRANSIENI gTL.T.I2(ccn'tlTRANSIENfTRIP/SAfECUARO FLNCTIOIfORRX1RIPtfSARltl,telg)INPACTOFCOHHOIHCOEFAILURE(CKF)ON'fRIPfUNCTIONALARH/ALTERNATE IIOICATION STSIEHAVAILABLE'IACRAH gCONSfOUENCFS OFLNAVAILASILI ITOF0IVERSEALARHEVALUATION OfEvfNIearlierLhsnnodctedduetolossofvoltageandRCPbusuodcrvoltsgc.

thereare~Isoseveralalternate eterneavailable totheoperator.

Thcsteangenerator leveldeviation atarstlsavailable torIou-Iousteangenerator uaterlevel.Nighpressurizer prcssuredeviationandhighpressure~Tarosarcalsoave(labia.

Thercforc, thereIsnoadverseicyactoftheCHFoftheRPSonthisevent..22~

UNIII2ISARIRAHSIEHI SIC.I.ISIRANSIEHIIwhine.generator safetyAnalysisIRIPISAFECUARO FUNCIIOHFORRXIRIP(FSARILI.I~)3)IKPACEOFCCHHQHHOOEfAILURECAlf)OH1RIPfUHCTIOHALARIMALIERHAIE INOICAIICH STSIEHAVAILASLE OIACRAHSCCHSECUEMCES OfLNAVAILABILIIV Of0IVERSEALARHEVALUAIIOH OfEVEHIIbiscvcntlsrelatedtoncchanleal failureofthecainturbine-Scnerators.

1herelsnoreactortripassoclatcd ulththisanalysis.

Ifthereucrctobeafallur,oneornoreturbinetrips,uouldbeexpected.

Areactortrip,toaffcctedbyCHF,uouldresulttreetheturbinetrip.Ihcre(ore, thecocooncodefailureofthesoftuarcofthencudigitalsystccthasnoIspactonthisevent.

UNITIFSARIRANSIENI NIt.2.ITRANSIENT RadloIOQIcal consciences offuelRandllnyAccIdentIRIP/SAfECUARO fUNCIIONfORRXTRIP(fSAR)q.g.i)IHPACTOFCCNHOINCOEFAILUREICNF)ONTRIPFUNCTIONALARM/ALTERNATE INOICATION STSIENAVAILABLE DIABRArlsCONSEQUENCES OFUNAVAILABI LITTOFOIVERSEALARHEVALUATION OFEVENTBoundlnsfuelconditions areselectedforthe~nalyslaof~hypothetlcaL droppedfuelassesblyforbothUnjt1andUnit2.Theyaredescribed InfSARSectionsUnitI,Tt.2.1andUnit2,IS.3.$-3.Theseanalysesalsoassuaethatthe~ccldentoccursIOOhoursaltershutdoun.

Sincetheaccidentoccursshenthereactorls~lreadytripped,thecoseonnodetallweoftheneudigitalequipoent hasnoeffectonthisevent.

UKIII2fSARIRANSIENI 4It.2.2IRAKSIEKT Postulated Rcdloaotlvc ReleasesdkkctoLl~ld.Containing TanhfailuresIRIP/SAFEGUARD fUKCIIONFORRXTRIP(fSARltl,+D.)IHPACTOfCCHHONHOOEFAILURE(CHF)OKTRIPIUNCTIONALARH/AL'IERNAIE IKDICATIONSTSTEHAVAILASI.E DIAGRAHdCOKSEOUEKCES OfUNAVAILABILITY OfDIVERSEALARHEVALUATION OFEVENIThiseventlsnotaffectedby~reactortriporsafcswrds actwtlon.

Thcrclore, ihecoamonskodcfailureofthesoftuareotthencudlDltalcqullsacnt KILLnotla@acttheresultsofthiseven't-2Sk~~k UNIT'Iand2fSARIRANSIENT

~I(.2.3TRANSIENT Accidental M4$tecasReleaseIRIP/SAfECUARO fUNCTIONfORRXTRIP(fSARtg.X3)IHPACTOfCOHHQNHCOEfAILURE(CHf)ONTRIPfUNCTIONALARH/ALTERNATE INOICATICH STSIEHAVAILASLE OIAGRAHSCONSEOUENCES OfUNAVAILASILIIT OfDIVERSEALARHEVALUATION OfEVENIThiseventIsnotaffectedby~reactortriporsafcguards actuation.

Therefore, thecocaan~nodefailureofthesoftuareoftheneudigitalreactorprotection systcnHillnot(epactthcresultsofthisevent.Intheeventofavotuaecontroltank(VCT)rtpture,VCTIoulcvctardVCTlou-louLevel~Iarnsuoutdbeanticipated.

Variousradiation 4(arneuoutd~lsobeanticipated Inc(udiny thetiltventaiar44AVCTIoulollLevelklLLresultlnarefuellnSHatersequenceuhlchHillstarttheshutdounofthereactor.Thiscccblnatlon ofslamsandaut004tlc actionsuou(dleadtheoperatortoIsolateIctdounandproceedulthanorderlyshutdoun.

ThisscenarioIstnaffectcd byCHfofthencuccqulpncnt.

,Il'IiW' UNltI2ISARTRANSIENT 4I(.2.(IRANSIENTStcaagenerator tlbcRuptureTRIP/SAFEGUARD FUNCTIONFORRXTRIP(CESARIl(,q.t()

I.Reactortriponlouprcssurlter prcssuresignal2.SafetyInjection onprcssurltcr prcssure-lou IHPACtOFCOHHONHCOEfAILURE(CHF)OITRIPFUNCfIONReactortriplost(ecaodated10/13/92freeM.O.SotostoV.D.Vsndcrgurg)

SafetyInjection lost(t/SIable3.3.3)ALARH/ALTERNATE INDICATICN STSTEHAVAILABLE fKII~cnAvallabtPanelndlectionPanelrecordercocputcrIndication IcAeralAvctcbLouprcssuredevation(turnonbackupheaters)viacontrolsystcaNighradiation alaralntStcaagenerator bioudounLiquidStcaajetair~Jcctorvent~tflucntradiation eonltorSteaagenerator hfghleveldeviation (InaffectedS.C.)Pressurltcr Louleveldevi~sionviacontrolsysteaPrcssurlzcr Loulevel(blockpressurttcr heaters)viacontrolsystcaDIACRAH0fD.2101CONSEOUENCES OFUNAVAILASILLTT OfDIVERSEALARHEVALUA'IIONOfEVENtlhereactortripaccusedforcalculating theaasstransferfraathereactorcoolantsystcathroughthebrokentubeInthiseventoccurscnLoupressurltcr prcssuresignal.ThlctriplslostbecauseofcoceonNodefailure(cHF)oftheneudigitalcqulpacnt.

Thcsafetyinjection lsalsolostIfCHFofthencudigitalcqulpacnt occurred.

1hestcaagenerator tuberuptureeventuouldresultIn~decreasetntheprcssurltcr prcssure~ndlevel.Thcprcssurlzcr pressureloudcvlatlon

~Lcraat25psigbcloucontroller'ctpolnt (noresLcontroller sctpolntls2085pslgforUnit1and2235pslgtorUnit2)(Procedures 1,2-ONP(02(.100,

.200Drop0)~ndthepfcssurlzcr leveldeviation alaraatSSbcloulevelprograas.

(Procedures 1,2-ONP402(.108,

.208Drop()uoutdactwte.1hls~ccidcntcanbeIdentified bythcoperatorbyeitheracondenser air~Jcctorradiation alaraorastcaagenerator bloudovnradiation alara(FSAR,pageT(.2.(-SandSD.DCC-NE 101).Ihestcaagenerator highleveldeviation

~laraforthefaultedstcaagenerator ls~lsoavailabl~.FOLLoulng thesealsres,theoperatoractionsarespecified byplantprocedure 01-ONP(023.E-3.

'thiscaergency procedure ulllguidetheoperatorthrougheltlgatfon ottheevent.ItIsanticipated thatthelncrcecntaL tiesfortheoperatortorespondtothe~laresproducedbythfsevent,cvalwtetheappropriate Indications, andactuateprotection andsafcgwrds factionsviLLresultlnarcletlvcly saslLtncrcaseinthetransferotfluidtroatheprfaarytothesecondary systca.TheEROgackground DocuacntforE.3,SOIRIndicates onp2dthatalthoughthelevelIntheaffectedstcaagenerator aayreachthetopofthenarrourangespan,slgnlfleantvoluaestillexistsbeforethcsteaagenerator fillsulthwter.Procedure 12TNPd020LAS.122providestheguidelines foractionstakenbasedonstcaagenerator prlaarytosecondary leak.2t-

~~~~~t~.'I V

UNITI2fSARTRANSIENT NIL.2.5(cont'd)TRANSIENT TRIP/SAFEGUARD fUNCTIONfORRXTRIP(fSAR)g.2.g)(II)Nighsteanfloucoincident

<<IthLo-LoTavg(III)LousteanprcssureIntaoloops(Unit2)Nighsteanfloucoincident ulthIousteanprcssure(Unit1)IHPACTOFCO%ONHCOEfAILURE(CHF)ONTRIPFUNCTIONLostLostALARH/ALTERNATE IHDICA'IIOHSTSTEHAVAILASLE'd aonsAvaablrecorders ndcva~bePanelndlee'tlanCocputerIndication SteanfiouIndication frotcnonCHF(Unit1)0herAaresrdlcaILouprcssurlterleveldeviation Louprcssurlter levelSteangenerator highleveldeviation centslnaentdevpoTntnonItor(ches'ked atleastonceper~lghthours)Icacondenser InletdoorsopenOIACRAHNCONSEQUENCES OfUNAVAILASILITY OFDIVERSEALARHEVALUATION OfEVENIortakenanuatactiontotripthus.IheEaergcncy Operating procedures basedcnEoergency Responseguideline f.-O(HP-Rcv.1$

)providerecoveryguidelines totheoperator.

Slrpleextrapolations suggestthat,ulthaddeddelaysforoperatorresponse, therctwntopouercouldbeslgnlffcantlyhigherthancalculated forthefSAR.ThiscouldresultInfuelcladdaaage.Kouevcr,ItlsnotbelievedthatthisHillpreventtheoperatorfronbringingthealttoasafecondition usingthcEcergency Operating Proccdurcs.

1hecnvlronaental (epactoffuelcladdosagelsdiscussed lnSectionT(.2.7..29-V\I~F'gr UNITIandUN2fSARIRANSIENI gI(.2.6'!RANSIENt RuptureofControlRodDriveItcchenisn (CRDN)Mousing(RCCAEJcctlon)

TRIP/SAFECUARD fUNCTIONFORRXTRIP(fSARItl~1.C)1.Reactortriponhighneutronflux(highandlou$<<sting)2.ReactortriponhighrateofneutronfluxIncreaseIMPACTOFCONANNODEfAILURE(CNf)ONTRIPfUNCTIONNotaffectedNotsffcctcdALARH/ALTERNATE INDICATION STSTENAVAILASLE DIACRAN4CONSEQUENCES OFUNAVAILASIL ITTOfDIVERSEALARNEVALUATION OfEVENT-eforthisevent,thetuoreactortripsoccuronNISoverpouer setpointandthehighrataofneutronfluxIncreasesctpolnt.

1hesetuotripfact(onearenotprocessed bythencudlgltaLcqulpacnt.

'therefore, thefSARresultsofthiseventarenotaffectedbythccosnonsxdefailureofthencudlgltalreactorprotection systcnKoradlologlcal doseasscssncnt Maspcrforncdg butthcdosereceived~Isltcbolzx4ryandaLoupopulation zoneuouldbenlnlnaL(Unit2fSAR,pageI(.3.5-5).

Theasscssocnt prcvlously perforncd byAdvancedNuclearfuels,uhlchlsIncludedlnTablesIC.3.5-6through1$.3.5-9,shoothatthedosesforthisace(dentareuelLbelouIDCfRIDOguldelInes..30-UNITIandfSARTRANSIENT NN.2.7'IRANSIfNI Secondary SystccuAccidentEnvlranacntat Consequences (thisSectionolUnit2fSARreferstoSectionIC.3.5ofUnit2fSAR)TRIP/SAFECUARO fUNCTIONfORRXIRIP(fSARItf.2.t)LossofExternalElectricLoadLossofNarcclfeedsterLossofalLACPowertoPlantAuxiliaries fuelHandlingAccidentLockedRotorEtc>aGenerator tubeRuptureRuptureof~StcuaPipeRLptureofaContralRadDriveHcchanlsu AssccblySingleRCCAAssccbtyMlthdrawai IncidentLOCAIC.I.O1C.1.9IC.1.12IC.2.1'IC.1.6.2 IC.E.CN.2.51C.2.6IC.3.11(.3.2TableIListsallcvcntswithdoseconsequences andIrdicatcs wherethcprotection/salcguards flActlone4refound~TASlfI0lS(USSICH~OFVE~NIHPACTOFCCHHONHCOEFAILURE(CHF)ONIRIPFUNCtIONScctASLEIALARH/ALTERNATE INOICATIONSYSTEHAVAILASLE SeeTASLEIOIAGRAHNCCWSEOUENCES OfUNAVAILABILITT OF0IVERSEALARHEVALUAtION OFEVENTIbissectionIncludesthediscussion ofthecnvifanacntat consequences of~canaanaxdcfailure(CHF)ofthedigitalFoxborocqulpeent anseveralcvcnts.TableIlListsalleventsforwhichdoseconsequences willbefound.tASLEIIEVENTLossoffxtcrnaLFlcctrlcloadLossofNaruaiFccdwatcr LossofAllACPowertoPlantAuxiliaries, fueLNardttngAccidentLackedRotorSteanCcncra'tor TubeRaptureRuptweof4steanPipeRuptureofaControlRodOrlvsHcchanisu HousingSingleRCCAAssccblyUlthdrawal IncidentLOChRAOIOLOQICAL0IS(SISSICH~OFV~ENIC.2.'7(thissection)IC.2.7(thissectlcn)'IC.2.7(thissection)IC.2.1N.1.6.21(.2.7(thisacctten)IC.2.7(thissection)IC.2.6IC.3.5N.3.5Thecvatuatlans ofthcLossofExternalELcctrlcal load(IC.I.S),

lossofNorualFccdwater flow(IC.1.9),

andLossofallACPowertothePlantAuxiliaries (1C.1.12) didnotIndicatethattheautcoaesoftheseeventswouldcaeproatse anyofthisfissionproductbarriers.

Theseevaluations sssuacdaiarsctfrostcontrolsystcesorotherindications toalerttheoperatortotheneedfaraction.Itwasthenaccusedthathewouldtakeprocptactioninaccordance withhiseacrgcncy operating procedures tonasallyactuateprotection andsafcguards factionsasappropriate.

Sincenocaapruaise ofthefissionproductbarriersresultedfrautheevaluations, theincidentoffsitedosesdescribed~

!nScctlcnIC.2.7.2reaatnvaltd.forthesteaubrcakevent,theevaluation ofscctlonIC.2.5suggestsapotcntlaL higherreturntopowerwhenadditlonaL ticels~lloc4tedforoperatorfcspaAsetoswwxutty-31.

~'h UN11I<<XI2fSAR'IRANSIENT gIC.2.7(cent'd)IRANSIENT TRIP/SAFECUACD fUNCTIONfORRXTRIP(fSARtq.2.q)INPACTOfCOeCONIKNEfAILUREICHF)OHTRIPFUNCTIONALARH/ALTERNATE IIQICATIOH SYSTEIIAVAILABLE OIAGRAHgCONSEOVENCES OFUNAVAILASILIIY Of0IVERSEALARHEVALUATIOI OfEVENtInitiatesafecyInfection.

Itthistcuhtocledfatlure,thcinventory otradlolsotopcs InthereactorcoolantafccrthaeventulLIbelargerthanaccusedfntheIC.2.2anatyslc.

Noucvcr,theanatyslsfor1Xfailedfueland\0gpaprlaarytoscc<<vhryleakrateshous~0.0hrsitetxxndarythyroiddostotCr<<aanda0.3rcasiteboundaryahoisbodydose.Thesevaluesarctuoordersofaagnttude bclouthc10CfR100acceptance criteriaof300rcaand2Srcaforthyroidanduholcbodydosesrespectively.

Sincethesevaluesareaverysaattfractionofthc10CfR100crtterla, Itappearsthatctadfallwculllnotcausathesecrltcrlatobe~xcccdcdAnanalyststosapportatccrnati steangenerator tubepluggingcrttertaforUnit1hasbeensdxattccd totheNcc.Theanalyststadcscrtbcd InUCAP-131ST.

ItInchdcs~aethodology toensurethatthcoffattadoseIsItaltedto30rcathyroidatthesiteboundary.

thisanalysfs~saucesa'IXfueLdefectsand~120gpaleakduring~steanbrcak.Ateachoutageuhcnthesteangenerators arecxcalncdfordegradedtubes,~ccnservatlve evaluation NilIbcpcrtoracd toensurethat,InthecvcntofasecanttnebrcaL,the120gpaleakrateIsnotcxcccdcd.

If~potcntlat returncopoucrshoutdresultInaddltlcnal claddaaageabovethataccusedInthtscvaluatlce, the30rcacricerlcn couldbecxcccdcd.

Koucvcr,30rcaIssnailcocparcdto10CFR100llalts.Nefurtherobservethat,Inaccusingculclplafailureslnsafcguarch actuation, Itisnotalsonecessary toassuaeotherfallwcsasuett.Iticlsaccusedthatattrahinsert,theveryLargeFoassociated utththeanalyzedreturncopoucrutilnotbepresent.Thesefn'scanbe10.ItIsicheporclonofthecoreassociated ulththispoucrpeakthatlsexpectedtosuffercl<<tdaaagcFwthcraoreg Ihcnrodsarcinserted, theSOHutilbedxktcdornoreaccusing~stuckroduorthgreaterthanor~peaandexcessSOH>COOpea.Icshouldalsobenoted,asdiscussed InSectionTC.2.S,thatattaropoucrorloupoucrs,rxctcarInstruacntat iontripsfrcathasourcerangeandtntcracdlate rangedetectors andthepoucrrangehighrangelousctpolntareexpectedtoprotectagatnstpaverexcursion c~

~~50EJN,'~'

UNIT'Iand1CESARTRANSIENT gIC.2.7(cont'd)TRANSITNTTRIP/SAFECUARO FLXICTION fORRXTRIP(fSARIq'2'7)I<<PACTOfCC<<NONHCOEfAILURE(CNF)ONIRIPFUNCTIONALARN/ALTERNATE INOICATION STSTEHAVAILABLE OIACRANgCONSEOUENCES OFUNAVAILASILLTT OfOIVERSEALARNEVALUATION OFEVENTFlnaLLy,<<ebelievethatlnthecaseof~largesuddensteanbrcak,there<<ILLbeasafer~udlbiaIndication

<<hlch<<auldproepttheoperatortocarlyaction.Ifthcbrcak<<cretodevelopgradually, thevariousclamsavailable

<<illallo<<theoperatortotakeactionInatinefraaethat<<illpreventanycladdanage.Therefore,

<<econcludethataCHFincocbinatlon

<<lthotherfailurescouldresultlnreleaseslargerthancurrently calculated butnotincxccssof10CFR100If<<its.In~noreLikelyscenarioIn<<hfchlargecorepeakingfactorsareavoided,thccurrentcalculations arccxpcctcdtobemaffcctcdbecauseLittleornocladdc<<age<<ouldresult.ShouldCNFoftheneudigitalcquipxcnt occurforthesteangenerator tobertptureevent,theoperatorhastotripthcreactorannuallyandIsolatethebrokensteangenerator folio<<lng theguidelines givenfncncrgcncy operating procedures.

Ithasbeenassuacdinourevaluation thattheoperator's responsetfaelsMseconds.ThisoneninutetineIson~ddlticntothe30nlnutcsallotcdforoperator~stionafterthcaccident, ulthln<<hlchtinethepressurebct<<ccnthedefective etc<<agenerator andtheprlaarysystcnIscquallzcd, andthedefective steangenerator lcIsolated.

Assuaing~Igpaprlsary-to-secondary leakrateIsaxlsxxa leakrateaLLo<<edbyT.S)priortothetuberupture,the0-2hourdosesatsiteixxxvfary are:thyroid1.7re<<I<<holebodya0.02 rcn.Thesedosesareeuchlo<<crthan10CfR100guidelines of300rcathyroidand25rcn<<holebody,respectively IUnlt1fSARpageTC.2.7.6).

Thcdosesatthecndof31alnuteoftine<<auldbenfnloaLIy lcf>>ctcdbythedelaylnsafeguards actuation h)potheslzcd foraCNF.Therelease(orSCTRareexpectedtorcnafnouchLessthan10CFR100gufdcllnes evenshen~CNFls~sauced.33-

UN!I2CESARIRACSI(ct S1(.2.8IRANSI(NI HajorR~tufcofHainFccdvatcr Pipe(fcedllne greek)TRIP/SAFECUARD FUNCTIONfORRXIRIP(fSARLQ.2..$)~)Areactortriponanyofthefolioulng condltla>>t 1.Highpresswlterprcssure2.Overtccperaturc 4T3.Lou-loustcaagenerator vatcrlcvclfnanysteangenerator C.Safetyinjection slgnalcfrooanyofthefolloulngt (I)TuooutofthreedlffcfcAtl~Lpfcsswcsfgnatsbctvecn4steanLIAC4Adthoreaalnlng stcaotines(ll)LoustcuaprcssurelntvooffourLfnes(lll)TuooutofthreehighcentaltvacntpfcsslJf4SignetsIHPACTOFCANONHODEfAILURE(CHF)ONTRIPfUNCTIONTriplostTriplostTripLostSignallostSignallostSignallostALARH/ALIERXATE INDICATIONSTSIEHAYAILASLE Adc4onAvaab~PancLlnslcatlon

~Panelrecorder~Cocputcrindication IvereAaresAvailable controlsystcN~Nlprcssure(2325psla)vi~controlsystcct~Threehighprcssure~Laresat2350psla(occ>>dated10/13/92fresM.A,SotostoV.D.Vandcrgurg)

MlderangeRCStccprecorders AdIcetIAvaab~PanelIndcation~Panelrecorder~Cccputcrindication IVAafll!$AV4ab'LCVCLdevi~tionviacontroLsystea(cenodated10/13/92fraaM.C.SotostoV.D.Vandcrgwg)

Ad4AveableCofputcrIndication saoeasfordlffcrcntlal prcssuresignalIldatVaahtCocputcrIndication AafccAvaUppercentalrfacntprcssurehighorlou(tuostare>>)DIACRAHgFD-2101SheetIf0.2102Shcct3FD2101Sheet5CONSEOUENCES OFUNAVAILAS ILITTOFDIVERSEALARHEVALUATION OfEVENTThiscvcntuasonl'ycvaluatcd forUnit2.ItlsnotInthcUnitILicensebasis.AUnitIanalysisIsprovidedlntheUnitIUfsARforlnfofc>>tioncnly.theFSARanglyslsforthiseventhasbeenperforcedatfullpouerulthOASulthoutlossofoffaltepouer.Thisanalysisassuacsthat~reactortriplsinitiated ChentheLou-Lousteangenerator leveltripsctpolntIntherupturedsteangenerator lsreached.ThcLou-Lousteeagenerator uaterleveltripIslost,If~coc>>oncodefailure(cHF)ofthencudigitalcquipacnt occuf4AllthereactortrlpcandsafetyInjection signalsullLbetost(ColumC)cahcnCHFofneuequlpacnt occurs.goththeaeterdrivenandtwblnedrivenauxiliary fecduater systcc>>arealsolostexceptInsituation descrlbcd betou.Ihca>>tordrivenauxllfafy fccdvatcr TxnpsarenotaffectedbyCHFIfthepwpsstartedonCCVtx>>Lossofvoltageorlossof~LlNeinfccduatcr pwt>>(1/STable3.3-3,page3/A3-19).Thcturbinedrivenauxiliary fecduatcr FxaplsalsonotaffcctcdbyCHFlftheIxupstartedonreactorcoolantpwpbustavfcrvoitage (I/Stable3.3-3,page3/L3-20).tncaseofCHFofthedigitalequipacnt, steangenerator leveLdevlatlcn clara,prcssurlzcr prcssureloudeviation clans,prcssurltcr louleveldeviation

~lena,andprcssurltcr loulcv<<Lclaraareavailable totheoperator.

Inaddition, threealternate Indications ofthestcaagenerator uaterlevel,prcssurlter

prcssure, andprcssurfter levelareavailable totheoperator.

Theseclara>>endIndlcatlcns arccapes\cdtocausetheoperatortoInttfaieprotective andssfeguards actionrelatively earlyIntheevent.Usingthccoergcncy operating procedures, theoperatoruoutdveryLikelyapplyauxiliary fCCduater tOthe!ntaet SteaaDCneratOra Carllerthanthe10alnutcsaftertheInitiation assuacdintheanalysis.

Inaddition, uedonotbelieveItIsnecessary toassuaeanAFMpwpfailurelnakllttontoCHF.Invleuofthisandthefactthat~conservatively soallfecduater flouof.3C.1 ISARTRANSIENT gIt.t.6Ieontrd)TRANSIENITRIP/SxfECUARD FUNCTIONfORRXTRIP(FEAR1'I>9)b)AuxlIlaryteeduater ll)1uoactordrivenauxiliary fcedvatcr purpsuhlcharestartedont~LouIouLcvcLIAenysteangcAcrator b.TripotaILaalnfccduatcr c.AnysafetyInjection signald.Lkvbuslossofvoltagee.Hcrxlslactuation III)turbinedriven4uxllfaryfccdvatcr Fxnplsstartedcnt4~LoulouLcvcLInanyCliosteangenerators b.ReactorcoolantprpbusIxdcrvoitage IHPACTOfCOONHHCOEfAILUREICHf)OH'fRIPFUNCTIONIOAfPstartsIwtoeetlc initiation) orLou-Iousteangenerator LevelardsafetyInfection tronnon-ACISICIInitiation arelostIDAFPstartIwtoaatle fnitiaticn) onloulousteangcAcr4'tor lovElIsLostALARH/ALTERNATE INOICATIONSTSTEHAVAILABLE AdI~Pressurltcr pressureLoudeviation

~Presswlzcr levelloudeviatton~Prcssurlzcr Ioulevel~Prcssuritcr highleveldcvlatlon

~Prcssurltcr highLcvctOIACRAHgCONSEOUENCES OFUNAVAILABILITT OF0IVERSEALARHEVALUATIOH OfEVENt600gpawsaccusedtobeSIBTILlcd tothaIntactsteoageneratOra, aSIbetantlatty targcr~uxlllaryfceduatcr tloucanbeexpectedtobesuppliedtotheIntactSteanBCneratora.

Cnthisbasis,ltlslikelythattheeventnotonlyuoutdnotbeuorsethantheanalytcdcase,butcouldLikelybelesssevere.At~IIpoucrs,thesteangcncrator lcvcldevlatlon claraIsavailable.

Inedfltion, Auserousslamsdescribing thestatusofthecondensate andfceduater systceixnpsandpressures, suchascondensate hotwllLevel,boosterootortrip,neinfecdvater fxnp,etc.ulllactivate.

Uhcnatleasttuochannelsoffccdvater arelostaboveAOX,thcAHSACttoerulllalsoinitiate.

IfthetlcgrIsattouedtotineout,~turbinetripandwxlllaryfceductcr Ixnpstartulllbeinltlatcd.

TheturbinetripulllresultIn~reactortripuhlchIsIxlaffccted byCHF.

~**P UHIIIan@ISARTRAMSIEMT 4IC.3.1TRAMSIEHTLargeBrcakLossofCoolantAccidentTRIP/SAfECUARD fuMCTIOMIORRXTRIP(fSARL4.3~I)1.Reactortriponlouprcssurlzcr pressure2.SafetyInjection (Sl)onIcwprcssurlzcr prcssure3.Containacnt sprayonhi~hlprcssureIMPACTOf(XZCQNHOOEIAILURE(CHf)OHTRIPIUMCTIOMReactortriplostsafetyInjection signallostHlhlpressurespray~ctuatlonandESFtriplost.ALARH/ALTERMATE IMOICATIBMSTSTEHAVAILABLE ndatAvatabt~PanelIndlcaton~Panelrecorder~CccputsrIndication ve4fasAvaitabPrcsswlzcr prcssureLoudeviation (turnonbackupheaters)viecontrolsystea(aeeedated10/13/92freeU.C.SotostoV.D.Vanderburg)

PanelIfdlcationCoefwtcrlndlc4tloA vcAefecAvailablUppercontalffacnt hl/Lopfcssufc~Lares4v41lablevia.ccntrolsystca(oecedate10/13/92froaU.G.SotostoV.O.Vanderburg).

0th~AdIcatILowrcontainacnt radiation Monitors(isolated onphaseg).Upperccntalffaent arcsradiation aonltors.

Postaccidenthighrangecon\clffacnt afc4aceltol'4

~Pressurizer Levelloudeviation clara.PrcssurlacrLouLevel~lara.Lowrcontalnaent slaplcvclhigh.ConteI<<sent~Irtccper4twe highAccusulator Levelhighorlou(onaal~fapcf'ccuaJI

~ter)~Acclaulator prcssurehighorLou(oncalaraper~ccloutator).

RCShotlegpressureLOURCPSeal1diffprcssureLou(CACclarapcf'CP)~OIACRAHgI0.2101Sheet1COMSEOUEMCE'S OfUMAVAILABILIIYOfDIVERSEALARMDiverse~laraforLoprcssure(turncnbacklpheaters)viecontrolsyst<<als4v4ILabtc Consequences ofteavaltabllItyofSlsystcaisdecreasing RCSInventory resulting InanIncreaseofpeakcladtccpcratUfc, Iheonlyprotective flectionpriortooperatoractionMillbaccclaulator injection.

ThcoperatorUIILbelnutdatcd by~Iafasforthiseventasindicated lsdertheotherAlafas/Ifdlcatfons heading.Nevertheless, w~ssuaeMsecondsfortheoperatorresponsetlac.Sincethaoutcoaeofthiseventdependsonproeptsafcguards actuation, 44aodclcdUAdef'pp<<dlx Xrules,~lcvatcdPCTandextensive fueldaaageMouldbeexpectedtobacalcUla'tcd by<<lAppcfdlxKaodeI.EVALUATIOH OfEVEMTThcfSARanalysisofthiseventshousthatalargebrcakLOCAUithdischarge coefficient (cd)of0.6istheaustllaltlngcasaforUnit2UlththeRHRcross-ties open.forUnit1~aaxSlcaselsLlaltlng.

ThefSARanalysisassuaes~reactortriponloupressurizer prcssure<<dsubsequent lnltlatfon ofsafetyInjection, andacclxulator Injection at600pale.TheLouprcssurlzcr prcssurereactortripandloupressuresafetyInjection signalsarelost,lfacemxeaodefailure(CHf)ofthcncudigital!nstruaentatlon systcaoccurs.1heLargebrcakLOCAresultsInarapiddcpressurl tationofthereactorcoolantsystca(RCS).TheLoupressurizer prcssuredeviation claraMILLactuateat25pslgbelowcontroller setpolntof2235pslg(Proccduri 2.OHPC02C.200Drop0).figure1C.3.1-3a ofUnit2fsARshousthatthisalaraMouldactuatelnlessthancnescc<<doftransient.

Threealternate indications areavailable fortheIOMpressurizer pfcssure.

Thetaperccntelnacnt highprcssureaiafaMillactuateatC0.2pslg(Procedure 2.0HPC02C.105Drop31).These<<dotheralarasasfrdicatcd underOtherAlaras/indication effectively Harntheoperatorthat~aajoraccidentlsoccurring.

Accusingthattheoperator'a responsetlactoaltlgatetheeventls60scc.,thereactorMouldbetrlppqdatabout61secondsoftransient

<<dsubsequently InitiatethesafetyInjection

<<daccwulator Injection.

Inourevaluation, wassuaedthattheresultsgivenlnfSARaredelayedbyabout60secceds.frcafigure1C.3.1-15a, thepeakcladtccpcrature (PCT)of21CO'foccursatabout260accordoftransient.

LBLOCAlsaverycoepllcatcd cvcnttoaodcL~Therefore, extrapolations ofPCTareveryleCcftaln, AttccptlAB toCXtfapolat4 flgUrCSN.3.1-154 forUnit2andIC.3.1-13I forUnitIbyInserting

~delayof60accordsforoperatorresponsetlaesuggestsPCT'4ashighasthe3000'frange.HoueVCr,thercaLsituation lsInalllikelihood suchLesssevere.Bestcstlaatcaodcls4l'knountorccultlnslgotantf

~IlyLoverPCT's.Houevcr,evenIftheApp<<dlxX~36-1

'I+u~'~0I UNITIand<SAR[RANSIENT NIL.3.I(cont'd)

TRANSIENT TRIP/SAFECUARD FUNCTIONfORRXTRIP(ESARIMPACTOfCOHHOMHCOEfAILURE(CHF)OMTRIPFUNCTIONALARM/ALTERNATE IMOICATIOM STSIEHAVAILABlE RCPSealIleakoffIou(oneclaraperRCP).LoopRCPtriporLoufLou(oneclaraperRCP).icecondenser InletdoorsopenContalnaent deupolntconltor(checkedatleastonceper~lghthours).DIACRAHSCONSEOUEMCES OfUNAVAILASIL ITSOFDIVERSEALARHEVALUATION OfEVEMInodallsconservative byassuchasEOO~Fgtheacceptance crltcrlaforIOCFRSO.AS cauldctlllpossiblybeexceeded.

Althoughtheseestlnates oftheispactofaCHFonLSLOCAIsofconcern,ltlsunlikelythatsuchaneventMilloccurcndevennoreunlikelythatsuchaneventMilloccurlncoincidence ulthCHF.Asindicated lnSectionIL.3.3oftheUnit2UFSAR,pIL.3.3.4, pipeuhiprcstralnts andotherprotective cessuresagainstthed)naaiceifqctsof~brcaklntheneincoolantpipingarcnotrequiredbecause"Leakbeforebreak"canbeattunedtoallouforshutdounoftheCookUnitsbeforeaneventascatastrophic

~s~LSLOCAoccursThisarguaentalsogivesrcasonabl

~assurance thatsuchaneventinconJtnctionulth~CHFIsextrcnely tntIkeiy.

1P0'S~ft UHI'f12fSARTRANSIENT g14.3.2IRANSIENI LostolRcoc'corcooloncfroasaallruptwcdpipesorfroacrackslnLargepipeslhlchoccuotctheEacrgcncy CoreCoatingSystea(Brcakticec).OILZ)TRIP/SAFEQMRO fUNCTINfORRXTRIP(CESARII.3.2)1.ReactortriponLouRCSprcssure2.SafetyInJcctlce (SI)onLouRCSprcssure(autoInltletion)IHPACTOFCaeNHCOEFAILURE(CHF)ON'IRIPFUHCTINI.LopressureRxtriplost2.SI(aucoInlcIatlcn)lost(aeao9/2/92freeu.0.SotostoVD.Vtndcrgury)

ALARH/ALTERNATE INDICATION STSTEllAVAILABLE 1.PanelIndication Z.PanelRecorder3.CccputcrIndication vcAloraAvolobt1.PrcttwlterpressureIoudcvletIonvl~ControlSystca(acao9/2/9ZfroaM.0.SOCosCoV.DyonderBwg)OtherA(oratndlceonLouerconcalreent radlaclon cenicors(Isolated cnFhttcg)UpperContalleenc areared(scion tenlcors.

'resswlccr Levelloudeviation

~LaraPretsurlcer LouLevelalaraContalreent

~Incaonltor(checkedatLeastoncepcr~lghthours)OIACRAHgfg2101Rcv.00sheet1COHSEQUEHCES OFUHAVAILABILITT OFDIVERSEALARMDiverseAlaraforLoPresswcviaControlSyttcaIsavailable.

Consequence ofcnavaitabilicy ofSlsysccaladecrcaslny RCSInventory resuttlny lnanIncreateofpeakclodtccpcraturc.

IheperiodofcorecncovcrycouldbeextendedlfSltystcaItnococcuoccdln~Cleslyaorecr.(fSAR14.3.2)EVALUATIOH OFEVENTlhcsaallbrcaklossofcoolantaccidentresultslndcprctturlcacicn ofthereactorcoolanttyscca.TheLlaitlnybreak(asdeceralned bythehighestcalculated peakfuelrodcledcccperacure) forthchighheadsafetyInfection cross*cia valvesopenedls4InchesIndisasterforUnlc2and3InchesIndlaaetcrforUnitI~AcoldlcgbrcakuosInitiated atRCSprcssureof2100psiaandTavgof501.3FforUnit2.TheUnitIInitialTavguosSCTf.fortheUnit2case,theRxtripuasactuatedat1060pals(fSAR,pageIC.3.2.9).

IntheUnit2anatysls, thetifccyInfection (Sl)signal~ctuacedatITISpslaulth~Zysecondtlacdelaytoacccxntfordieselgcncrator scartupandcaergency paverbusLoadingIncaseofoffsltepouercoincident ulthanaccident.

Iheaoxfcxlofuelcladflnytccpcraturc sttalncdduringthetransient uas1C26f(Units2UfsAR,pose'IC.3.212).thecantoncedefailure(cHf)rcsulcsfnLossofbothLoprcssureRxtripandautoaatlc Sl.Hovcvcr,forLopretcurlter prcssur>>,

threealternate lndlcacicns, andlouprcssuredeviation viaccecrolsysccaDiverseAloneareavallabl~forthcoperatortotripthcreactoraueatly.1healara,PZRPrcssureLouDeviation BackupIlcaccrsCe,ul(Lactivateat2210pslg(Z.OHPC024.200Drop0).ThecorrcsPonding sccpolntls2060pslgforUnit1.SBLOCAltsverycccpllcsted eventtocade(aTherefore, extrapolations ofpCTereveryentertain.

Attccptstoextrapolate flgurcs1C.3.2-Cforunit2and1C.3.2-5forUnit1byInscrtlng anadflcfcna(

60secondsofhaecuptftetoaccocncforoperatorresponsecineInlieuofautceaclo actuation Ledtolncrcaental IncrctteInPCI'so(ASOOFald200'respectively.

ForUnit2thereIsaaarglntoaccocedatc a500'fPclIncreaseforthecross-t1~opencosa.ThaIncrcaental PCTuouldLeadcoonly1900ofpcf.forUnit1suchaorglnappearsnottocxlct.Roucver,theunit1SBLOCAanalyticuatpcrforacd at3560INTfor15xlSfuelulththeIntentofboundingbothUnits.Ifoneattuacstherul~ofttxab,CSofforeachISofDover,therelsCSOfofPCtaorglnduecochiccontcrvaclsa.

UnitI~30 ll UMIII2fSARIRAN1IENIN14.3.2leon'tl'IRANSIENI IRIP/SAFECUARD fUMCIIONFORRX!RIP(fSARI'4.gi)IHPACIOFCONNIMOEfAILURE(Cxf)CSIIRIPfUMCIIONALARM/ALIERMAIE IMDICATIOM SISIENAVAILABLE DIAGRAII0CONSEQUENCES OFUNAVAILAeltllf OFDIVERSEALARMEVALUAIIONOFEVEMI8Eoperatesat3250MufsndtherelsnoIntenttoIncreasethispaver.thusthereefpcarstobesubstantial pcfnarelnIntheAppendixKsstocAsadclforUnitIalso.liefurthernotethat,aslnthecaseofLSLOCA,theAppendixKcodellssbstantlatly ccnscrvatlve.

furthcrcorc, thcanalytedevents~ssuacdthelossofatrainofSlIxnps.Suchanasslrptfon, lnaddit'lon tothcsultlplefailuresotCMF,lsalso~slbstsnti

~lconscrvatisn.

Ihcrcforc, Itlsconcluded that,evenufthadditional operatorresponsetinesrelativetoautcoatlc actuatfon, IDCFRSD.S6acceptance crltcrfaMouldLikelybeaetfor-SSLOCA.IhehlehheadsafetyInfection cross-ties closedcasesMerenotconsidered becausetheCookUnits~reoperatedulththesecross-tice opencxccptforshortperiodsofsurveillance tcstfnSandnalntcnance.

~39-4 Ctk UNITI2fSARTRANSIENT 8IC.3.CTCANslENT LongTeraCont~insentIntegrity Analysis(SectionLC.3.Cofunit2referstoUnit1ufSARSectionIC.3.C)TRIP/SAfECUARO fUNCIIOHfORRX1RIP(fSARIIIQ.LL)1.Contslrrscnt SPfayonhigrlhighprcssuresignalIHPACTOiCOHHONHCOEfAILURE(CHf)OHTRIPIUNCTIOHLostALARH/ALIERNAIE ILOICATION STSTEHAVAILASLE

<ldcsonsAv4IablePanelIndlcatonCocfuterIndication vrsr<<aAvI4bUpperccntairyscnt h/loprcssurealarasavailable vl~ccntroLsystca(cccodated10/13/92froaU.O.SotostoV.D.Vsndcr8urg) otherAlar<<sAdltiPrcssurlzcr prcssureloudcvlstlcn (turnonbacklphcatcrs)vscontrolcysts<4LovercoAt~Inscntradiation aonltora(isolated OAphased).Upperccntal<vscnt arcsradiation sonltors.

Postaccidenthighrangecontalr<scnt arcsaonitors.

Pressurizer lcveLIoudevistIonstars.Prcssurlzcr (oulevelslane.Loverconte(<<sent swplevelhigh,ccA'tal<vscnt

~Irtccpereture high.Accus<Later lcvclhighorLou(cnealaraper~zeus<Later).

Accus<later prcssurehighor(ou(CACClarapcr"~ccus<Ictor).

RCSho'tlcgp<'cssufe louRCPScat1diffprcssurelou(cACalcfapcr'CP)~RCPSeal1leakoftloutonealsrapcrRCP).LoopRCPtriporLouflou(onealaraperRCP).Icecondenser InletdoorsOPCA,Contalnscnt dc<pointacAIter(checked4tlc4stoncepcreighthews)OIACRAH8f0.2103SheetCCONSEOUENCES OfUNAVAILASILITT OfDIVERSEALARHEVALUATION OfEVENTcnlythelongteraccntalnsent prcssureanalysislsconsidered Inthiscvalwtlon.

Theshortteraprcssureanalysestypically havepeakspriortothcactwtlonofanyprotective orssfegusrds fIs<etloneandcretherefore notapplicable tothisevaluation.

'Iheasssandenergyreleaseratesforstcaslincbreaksareconsiderably lessthantheRCSdaRIIC-ended flopsuctionPIPebreaks(UnitI,FSAR,P.IC.3.C-18) andare,therefore, bauIdcd.Theccntafnc<cnt tccpcrature effectsofstcaa(fne breaksareccnsldcrcd InSection1C.3.C/N.3.11, Electrical Equlpscnt Envirovscntal Ousllticatlon OtsssandEnergyReleaseInsideContalnscnt andOutsideContalr<ocnt).

ThefSARanalysisofthiseventshousthatpressurepeaksabout2hoursIdtothceventuhenthelcebed.colts out.Thcrctorc<

aslongasadditions(

energyIsnotaddedtothecontalrvacnt 4$4resultofcoo<sonnodefailure(CHf)otthenewdigitalInstrusentatlon, thepeakpressureshouldnotchange.InlargebreakLOCA,thereactorfsprocpt(yshutdounbyvoids.1hclongteraLOCAcoolinganalysis~tsuresthatItdoesnotbccoc<scriticalagain.ltactuation ofsafegusrds Isdelayed,PCTHillbeexpectedtoriseabovetheanalyzedvalueICItlLthecorelsquenchedatadelayedtineand,thcrctorc, additionfueldaccgeasyoccur.Houevcr<thcnctenergydelivered totheccntefr<scnt Isnotlfpectcdby4fclatlvcly snailchangeofaalnutcortuoInthere<Cove(ofthcraatenergyfroathccoreanddeliverytotheoontainscnt Inthecarlyalnutcsotthcevent.Itlsconcluded that~delayofafcuairs<teaIntheactuation otsafcguards Hillhavenofcpsctontheanalysisotrecord.fwthcrsore<

sinceItI~notnecessary toaccusethatonetrainofsafcgusrds fallslnaddlticAtoCHf,ltIsrcascnabie tobelievethattheoperatorcanaaruaLLyactivatetuofulltrainsofsafcgusrds 44rlylntheevent.cnthisbasis,ItlsLikelythattheeventnotonlyuouldAotbeHorsethanthcanalyzedcase,butuouldlike'lybelesssevere.~CO~

1,'I,>i UNI'IIand2ISARIRANSIENI gIt.).ttccnt~d)IRANSIENI IRIP/SAfECUARO fWCIIONFORRXIRIP(fSARINPACIOfCONHONNODEfAILURE(CNf)ONIRIPFWCIIONALARN/ALIERNAIE INOICAIION SZSIEHAVAILARLE DIACRANgCONSEOUENCES OfWAVAILARIL!

IyOF0IVERSEALARNEVALUAIION OfEVENIAlthoughthelapactofCNfonthecontainaent pressureanalysisdoesnotseentobesignificant, thepressureanalysislsbasedonLRLOCA.Itlstrdlketythatsuchaneventullloccurandevennoretnllketythatsuchanevent<<Illoccurlncoincidence ulthCNF.Asindicated InSectionlt.3.3oftheUnit2UFSAR,pIS.3.3-t, ofpipeuhiprestraints andotherprotective neasurcsagainstthedynaniceffectsotabreaklntheneincoolantpipingarenotrequiredbecause"leak-be(ore break"canbe~ssuaedtoallouforshutdownoftheCookUnitsbeforeaneventascatastrophic os~LRLOCAoccurs.Ibisarguaentalsogivesreasonable assurance thatsuchaneventinconjunction ulthaCNFIsextrenety mlikety.41 I'

UNITIand2ISARTRANSIENT I'IC.3.5TRANSIENT RadIologIcaIConsequences of~LossofCoolantAccident~ndotherEventsConsideration lnSafetyAnalysis.

IRIP/SAFECUARD FUNCTIONfORRXTRIP(FSARftf~$,5)Reactortrip/safcgwrd fcnctions arcIncludedinthecvatwtlcn offSAREventN.3.1.INPACTOfCCHHONHCOEFAILURE(CHF)OITRIPFUNCTION'cpaat ofCHFlsdiscussed lnth<<cvalwtlon ofcvcntN.3.1ALARHIALTERNATE INDICATION SYSTEHAVAILABLE Discussed InthccvalwtionofeventIC.3.'IDIACRAHgCONSEOUENCES OfUNAVAILABILITT OFDIVERSEALARHEVALUATIOI OFEVENT"lheUnit2UfSARanalysisofRadiological ccnsequenacs of~LOCAIncludesanalyseaofseveraleventsforradiological ccnsequenaes cfclchuereperforned byAdvancedNuclearFuelsCorporation.

Theseeventsarercvleuedforthelcpactofccccacnnodefailure((Hf)Inothersectionsofthisevaluation.

TableIIlatsalLcvcntsforuhichdose<<cnsequcnccs havebeenanatytedforCookUnitsIand2anfIndicates InRichsectionofthisrevlcuadiscussion ofthcIspactof~CHFantheradiological consequences ulllbefound.SectionIC.3.5oftheUnitIUfSARaddresses onlytheEnvlraccocntat consequences ofeLOCATABLEIDISISISSION~OF'~ENLossofExtcrnatElectricLoad'IC.2.7LossofNonaalfccchcater TC.2.7LossofAllACPouerto.PlantAuxiliaries IC.2.7FuelHandlingAccident'IC.2.1LockedRotorIC~1.6.2Steangenerator TubeRcpturcTC.2.7RcptureofastcaclPipe1(.2.7RuptureofaControlRad1(.2.6DriveHcchanlse NouslngSingleRCCAAsseahtyMlthdrawtN.3.5IncIdent(thissection)LOCAIC.3.5(thissection)'thasingleRCCAulthdraual cvcntuasanalytcdforUntt2forcycle6operattan.

As~partofthetransition toUcstlnghause fuelIncycled,AEParguedandtheNRCconcurred thatthiseventuasnotInthelicensebasisforDonaldC.CookNuclearPlant,Unit2.NRCconcurrence lsdocxsaented ln~LatterfreesJosephO.ClitterofthaNRCstafftoH.P.Alcxlch,datedAugust3c1989anlInthecycl~dSER,datedAugust27,1990.Therefore, noneuanalysisofthfceventhasbeenperforead.FortheCookUnits,slngl~RCCAulthdrauaL Is~ntlclpatcd tobeanevent<<lthninerconscquenacs.

The(nitsaregenerally operated~tfuLLpaverandbaseLoaded.Inthisaodeofoperation,'he RCCA'sarcnearlyfullyC2-tI'%I8g UNITIard2ISARIRANSIENT MI(.3.5(cent'd)TRANSIENT TRIP/SAFECUARO fUMCTIONFORRXTRIP/SAR]q.3g)IMPACTOFCONHONIKOEFAILURE(CHF)ONTRIPFUMCTIOHALARH/ALTERMATE INDICATION SISTENAVAILABLE OIACRANgCONSEOUEMCES OfUNAVAILABILIIT Of0IVERSEALARNEVALUATION OfEVENTufthdrakA.

Therefore, ulthdraual ofoneRCCAafcustepshasnoIrpact.Ifaunitshouldbeoperating at~reducedpoucr,anIncreaseInOMSRcksrgfnlsavailablc.

TheUnitssreoperatedusingthcconstantaxialoffsetcontrolckcthodsothatthecontrolling banklsscldtxadeeplyInserted.

Inaddltlcn, theroddeviation

~Lane,uhlchtsmaffcctcd byCNFkuouldbeexpectedtoalerttheoperatortotakeappropriate action.Thcevaluations ofsnailbreakLOCA(EventI(.3.2)andlargebrcakLOCA(EventT(.3.1)shouthatthelargebreakLOCAeventlsbounding, asthereuouidbesignificant cladfailure,Ifcoxsoncedefailure(CHF)ofncudigitalinstruacntat lanoccurred, slcultancously ulthaLBLOCA.Evaluation ofthelargebrcakLOCAevent(I(.3.1)shovethattheCHFofthcncudigitalapipaentcouldresultln~peakcledtccpcrature ofapproxicatciy 3000'fonanAppendixKbasisforbothtelts.Thictccperature exceedstheacceptance criterion of2200F,thugresulting insignificant cledfailureNKIrclcascoffissicAproducts~TheUFSARanalysisofthcradiotoglcal effectsofLOCAforbothUnitsfncludcstuocases.Inthefirstcase,Identified asthedesignbasis~ccldcnt.ItIsaccusedthattheentireInventory ofvolatilefissionproductcEonti~hIct-addsofallthefueLrodsIsr<<leasedduringtheticethecoreIsbeingfloodedbytheECCS.OfthegapInventory, SOXofthehalogcnsand100Xofthenoblegasesaraconsidered tobcreleasedtothecontalnacnt atskosphcre.

Inthesecondcase,ldcntlflcdastheSLaxlcuah)pothctlcal

accident, itIssssuscdthat50Xofthe~orI~OvenEXofhalogcnsandIOOXofthe~orIyfnnooofnoblegasesarerclcascdtothecontalrsaent auaosphcre.

tabl~T(.3.5.10 oftheUnit2UFSARandTable1(.3.$.2oftheUnitIUfSARdisplaythcdosesforboththedesignbasisaccidentandtheskSXicxxs hypothetical accident.

Asdiscussed Insection1(.3.1,thedelaysrclatcdtostRkstituting operatorrcspoAscticksforclcc'troAlc responseslakeCOuldresultlnsubstantially Increased

-43~~k I~II~"~<<<<~~~I~

UNITIandfSAR'TRANSIENT dIL.3.5(cont'd)IRANSIENITRIP/SAFECUARD FUNCTIONfORRXTRIP(fSARIq.3.y)INPACTOFCCNNCNNQOEFAILURE(CNF)ONTRIPFUNCTIONALARN/ALTERNATE INOICAIION STSTENAVAILABLE OIACRANNCONSEOUENCES OfUNAVAILASILI TTOfOIVERSEALARNEVALUATION OfEVENTfueldosageonanAppendixKbasis.No+ever,sincetheconsequences ofthecoxlsush)pothetIcalaccidentarebasedoncoreInvencory andsincetheyaccttheacceptance crltcrl~of'IOCFRIOO, ueconcludethatthe~nalyslsofthissectionlstnaffcctcd bycNF.UefurthernotethattheanalystsofscccionIL.3.5,p.p.IL.3.5-3, Sand13oftheUnit1UFSAR,assuacsonlyceetrainofsafcguards Including onlyoncCEO(anoperating.

Althoughnocexplicitly stated,itIsclearthatccntainocnt prcssurelsNaxlsLIzcd bydegradatlon ofcafcguards Including ccntalnscnt spray.ScefigureIS.3.5-3oftheUnit1UFSAR.Thesefailureacsuctpclons InadditiontoCNFarecxccsslve.

cAsIndicated Inthecvaluatlon ofSectionTL.3.1,therelssusbstantlal realaarglnIntheuseofanAppendixKnodaltoestlcotePCT.IClsalsocnllkclythat~largebrcakLOCAullloccurandItIscvcnsoretxdlkelythatcucheventullloccurIncoincidence ulthCNF.Asindicated lnScctlonIS.3.3oftheUnit1UFSAR,p,IL.3.3-L, pipeshiprestraints andotherprotccclve aeasurcsagainstthedynLslceffectsof~brcaklntheNeincoolantpipingarenotrcqulrcdbecause~leakbeforebrcak"canbeassuscdtoallouforshutdounoftheCookUnitsbeforeaneventascatastrofhic asaLSLOCAoccurs.Thisarguacntalsogivesreascnabl

~~ssurancethatsuchaneventInccnJcnctlcn ulthaCNFlsexcrccoly cnilkely.

~.D~'l%',J

),1Pe~0F1 UNIT1and2ISARTRANSIENT 014.3.6TRANSIENT N)drogcnIntheContalnacnt After~Loss.of-Coolant AccidentTRIP/SAFECUARD FUNCTIONfORRXTRIP(fSARILIgg)ReactortrIp/safeguard fuv:tlons areIncludedIntheevaluation ofeventIt.3.1.INPACTOFCCNNCHHCOEfAILUREICNF)ON1RIPFLWCTIOHIspactofCNFIsdiscussed In'thccvslU4tloA ofcvcAtIt.3.1.ALARH/ALTERNATE INDICATIONSYSTEHAVAILASLE Dlscusscd intheevaluation ofeventIL.3.1.DIACRAHgCONSEQUENCES OFUNAVAILASILITT OfDIVERSEALARNEVALUATION OfEVENTTherearctuohydrogenanalysesforthecookplantIacoodated11/16/92fruaR.g.RcmetttoR.S.Sharoa).Thefirstanalysis, Uhichls~partoforiginaldesignbasis,lsgivenInTSARIL.3.6.thesecondanalysis, AirhdocsnotappearInthefSARIs4responsetotheThreeHllcIslandaccidentLaceabovereferenced AUSO).Inthisanalysis, averyLargeavantofhydrogenIs4SSuacdtobegcACf4tCd by4scvcrelydaeagcdcore,cqulvalcnt to73Xtlrconlus

-Uaterreaction.

ThehydrogenIgnitcrsvereinstalled toensurethestructural integrity ofthecontainacnt buildingandsurvlvablll tyotcqulpocnt endInstrtsacnts Accdcdtostoptheprogression ofthcaccident.

TheNRCrcvicuofthisanalysislsnotyctcocpicte.

IIthcreactorsafcguards Initiation systcnUcretofallforlargebrcakLOCA,theevaluation ofSecticnTS.3.1suggestshfghPOPS.NighPCT'sUoutdbecxpectcdtoincreasethehydrogenproductlcn.

KCUCVCr,theh)drogcnignltcrsareexpectedtobeturnedoneavxallyforlargebrcakLOCAconditions throughtheStatus1rccs.ThcEccrgcncy Operating Procedures fR-2.1andIR.C.1UouldbeusedbytheoperatorInresponsetohighhighcontairacnt prcssurecndInadequate corecooling,respectively, toensurethattheignltorsUouldbeavailable.

IhUC$UfflclcAt Instfuacntctlon andprocedural guidancelsavailable totheoperatortoprcvcntanyadverseconsequences ofhydrogencoobustIonIntheeventofCNFofthcncudigitalequlfxacnt.

InSectionIS.3.1,ItUasconclufcd that,althoughthelcpactof4CNfonLSLOCAlsofconcern,ItlstntlkciythatsuchaneventUllloccurandevennoreLALIkctythatsuchaneventUlllocctxIncoincidence ulthCNF.Asfndlcatcd lnSectionIL.3.3oftheUnit2UfSAR,pIL.3.3.C, pipeshiprestraints andotherprotective acasurcsagainstthedynantceffectsof~brcaklntheUalncoolantpipingarenotrequiredbecause"lea'kbe(orebrcak"canbe~ssuncdto~LieuforshutdounofthcCookUnitsbeforeaneventascatastrophic as~LRLOCAoccUrs,Thisartxncntalsogivesrcasonabl

~assurance thatsuchaneventIncon]~tlon ulthCNFlscxtrceety tntlkeiy.-AS-iI'lV1 UNITI2,'fSARIRANSIENT NI1(.3.(N.(.IITRANS(EN(

Electrical Equ(paent Envlronsenc~IOuallIleatIOn(HaaaSAdEncfgyRclc4$csInsideCents(nsent andoutsideconte(Asent)

TR(P/SAFEQlARD fUNCIIONfORRXTRIP(fSARtw.SafetyInjection cnfo((ou(ng signa(st(I)TuooutolthreeLouprcssurlccr prcssuresignets(II)IuooutofthreedlffcfcA'clat prcssuresignalsbecueen~stcs<<l(A4<<dthere<<sining stcaallnes (III)Nighstet<<f(ou(nCuoLinescoincident ulthIou-(ouTavgIntuoloopsorsce<<aprcssureIouIntuoLoops(CnaanalysisboundsbothUnits)(Iv)TNOoutofthreehighCents(nsent prCSSureSigna(42.Reactortrip(I)Ovcrpover reactortrips(neutronflux)(II)OP41reactortrfp3.ReactortripInconjlx>>ttcn KithreceiptofchtsafetyInjection (SI)a(gnatA.Fccduatcr isolation onanysafetyInjection s(gnat5.Stcaa(lne lsotatlenl (I)N(gh.h(gh cents(lvsent PfCSSUf4IHPACIOfCOWOKHCOEFA(LURE(CNF)ONIRII'UNCflON SignetlostSignalLostSignallostsignetlostNoCsfftctedLostNOtaffCCCed(KOveVCr, Sll~uco<<at(cSlactwtlons areLast.(here(ore, thissfgnallsfix>>t(ontt on<<<<<<4(slInitiation only)Nataf(ected(Kouevcr,

~IIauto<<at(a Slactwt(ons arelost.thcrcforc, thissignalIsfix>>C(ona(

on<<<<ssa(Sl(n(C(at(CA cn(y)LostALACK/ALIERKATE INDICATION STSTEHAVAILASLE Panellnd(cation P<<>>lrecorderCcopuccrIndication IftAefe>>va(teb(CLoprcssuredeviation (turnonbackupheaters)vscontrolsysteaIcelonAvaablePanctlrdlcatonCoepuctrIAd(cactoA nd~lonAvelablSat>>4$fordtfcrcAcl~IprcssuresfgnatStc<<sflouIfdlcat(onfrotcnonCHFnd(aIAvablcP<<ltlIndic4c(CACotputerIld(cat(on IAAvebUpperceACSAsCACprcssurehighorlou(Cuo4(af<<s)vA~vabPoucrrangeoverpaucrradSCop(fiderangeRCStccpcrature recorders Panelffdlcat(on CosputcftldlcatloA r4AvatMeUppercanes(ra>>nt prcssureDIACIAHgCONSEOUEKCES OFUNAVQILASIL('lT OFDIVERSEALARHEVALUAt(ON OFEVEKt'thiseventIsdividedIntoCuoparts,HassandEnergy(HCE)ReleaseIns(deconte(lvsenc andHLEReleaseOutsfdeConte(le>>nc.

TheContalnsent Integrity analysisforthedoubleended(xopsuctionRCSbreakcaseboundsChe<<alnsteaa(lne brcakcont~insentprcssureresponse.

(UCAP11902,Slpp(ec>>nt I,pS-3.(-2).RcvlcuofthepressurecurvesinIJCAP11902Supp.IsuggestschatthereIssufficient

<<arginsothatthisKillre<<alnthecaseevenif$4fCgusfd$

4ctU4CIOA$

4fedc(eyedtF/Ico2<<inutes.Ifthisjldge<<ent shautdbeopt(<<lst(c andoneofthesteaa((ne HIEReleaseeventsShouldcausethesanta(nsent prcssuretoexceed12pslg,ItIsnotedthattheNRCIn~letterfra<<StevenA.VergeofthcNREstafftoHr.)ohnDolanofIndianaandH(eh(SanElectricCoepsnyaccepted36ps(gasthecence(nsent ultl<<atestrength.

Thcrcfore, thtc!ssue utilnotbeconsidered further.thetceperature prof((ca(nIICAP11902SlppIfortheHainStcaal(ne greek(HSLS)Cents(lvsent Integrity uerercv(cuedforthisevaluation.

TuoLl<<(tingtransients arediscussed.

'fheyare6.6sqftdaub(ecndcdrapture(DER)at102XRTPand~0.05ftsplitbrcakat102XRTP.DothoftheseIncludesfnglcfallurts,

<<@Instca<<Isolation failurefortheDERandwxlllsryfcedvatcr EFxlprlxvxltprotection failureforthesplitIclsAo'CAccessary coassuse'thesefailuresfnackl(tton tothecocnon<<odefailure(CHF)oftheneudigitallnstrusentatlon.

Thctetperaturc ardprcssurepeaksoftheDERoecUI'c6,(sccoAds<<d1(,01SccoAdsrespectively.

'IhtslsNellbe(orethefirstsafeguafds ofsteaallne Isolation at10.5ascendshutnearandafterreactortripati6seconds.Thcrcfare, ItI~tstl<<ated thattheIcpactoftheCHFuou(dberetatlvely

<<odest.thctccperature afdprcssurepeaksofthesplitoccurlaterat50.72ascends.Ihetccperatwe

<<dprcssuretrajectories areontheriseattheticeofthcpeaks.therisclstcf<<(nated bycents(nsenc spl'4'y(CtS)4ccU4cioA, Ic4ppe4rsthatthetecperature couldexceedche330'Fto(6 UNITI2ISARTRANSIENT NT(.3.(cndTL.L.II(cont'd)'fRANSIENI TRIP/SAfECUARDFUNCTIONFORRXIRIP(FSARL'I39+litcl'l(II)Nighstcaafloucoincident ulthLo'LoTavg(III)Nighstc<<afloucoincident uithLoustcaaprcsswe(Oneanalysisboc<<dsbothUnits)IMPACTOFCONNOMH(OEFAILURE(CNF)OHTRIPfUNCTIONLostALARM/ALTERNATE INDICATION STSTENAVAILABLE cxliconcAvclabclliderangeRCStccperature recorders PanelIAdlcatloA CocputerIndication Stc4a(louIAdlcatioA frolcnonCNF0hrAeratAdicaionLoupressurlterleveLdeviation Louprcssurltcr lcveLSteaagenerator highlcvcldcvi4tioAIcccondenser InletdoorsOPCACcntaincent dclpotntacnltor(checkedatleastoncepcr~lghthours).DIAGRAMyCONSEOUENCES OFUNAVAILABILITT OFDIVERSEALARNEVALUATION OfEVENflhlchcontalraent cqulpaent lsqualified lftheactuation otCTSucrcdetayedbyIto2alnutcs.Novever,transalttcrs aretestedto<00'Fandareencasedfnthickcastironcases.ItlsexpectedthatthethersaLLayofthesecasescanaccoccaodatc oneortuoalnutcsofdelay.CISactuation lsstep13ofEaergcncy Operating ProccdwcE.OandlsexpectedsoonafterentryIntotheprocedure.

MhcnCTSIsactuated, ItIsexpectedthatbothtrainsuculdbeavailable andthatthesprayMouldrapidlycondensethestcaaandcoolthecnvlronacnt totccperatwea uelLbelouthatcalculated inthcanalysisofrecorduhfchassuaesonlyonetrainofCIS.ThisIsexpectedulthapproxlaatciy oneMinutedelayrelativetothcanalysisofrecord.4Iheabilityoflheoperatortorespondtoavailable aiarasardIrdlcatlons andenterthccaergcncy operatiny procedures lsdiscussed InSectionI(.2.5.Itfsexpectedthatthedelaylnactuaticn ofsafeguards andprotective fc<<otloneMouldbeIalice.Basedonthisandthediscussion above,Itlsconcluded thataNLErclcaseoftheaaynitude oftheLlaltlngcasesulthaCNFMouldresultfnacceptable consequences, TheNLErclcasaoutsideofcontalrcaent Isanalyxcdtoensuresurvivability ofInstrMaents andcquipacnt Intheaainate<<aenclosures.

IhetoLloulng cvalu4'lion Isb4scdCA~a<<sodated11-20-92froaR.B.gannetttoR.S.Sharaa"CookNuclearPlant,FailureofReactorProtection Syst<<aIcpactofsteaallne BrcakinsideandOutsideofCcntafnacntc.

Inthlcevent,~largesteaafloueventually txlcovcrs thestcaagenerator tubcsi4LLCNIAgthacxltlngatcaatobcccaeScpcrhcated fnpassingacrossthetubes.Superheat lsthepriaaryconcerntorthiscvcnt.Prcssureaffectsareoverln~f<<cseconds,sothereactorprotection andsafcguerds actuation cyst<<cdoesnot'ccoeIntoplayforprcssureeffects.TheanalysisperforsxNf shousthat<forthellaltlnybreaks(1.0.1.2ftc),thcreactortripoccurredat108secondsorgreaterbasedon UNITIand2ISAR'IRANSIENI gL(.3.(handLL.L.II(cont'd)'IRANSIENITRIP/SAFECUAROFUNCTIONfORRXTRIP(fSARIN.IHPACTOfCCHHONHCOEfAILURE(CKF)ONTRIP(UNCTIONALARHJALTERNATE INDICAIION STSIEHAVAILAIL.EOIACRAHNCONS(<<UKNCES OFUNAVAILASILI TTOFDIVERSEALARHEVALUATION OFEVENI'JLo<<<<stcaa generator level.Significant Levelsofs<<pcrhcat occurredainutcslater.Sincethectc<<agenerator levelalar<<<<suouldbereached<<suchearlierthantheconservatively calculated stc<<agcncrato<<'evel

sctpolnt, theeffectsof<<Cainsteaaline brcakoncqulpacnt 3<<auldbeulthlntheanalyzedbourvfs.lheonlyplausible fastactingbreakisL.Cft2,<<hlchpredicts~reactortripat8secondsoneitherLoustcaollne prcssure(Unit2)orLoustca<<CIIne pressurecolncldcnt ulthhighstc<<af(ou(UnitI).Thereactortripat60sccgndsdelay(operators responsetioe)forI.Aftx~(88sec<<<<vff) shouldstillbebo<<xvfcdbytheanalyzed1.2(t~brcakulthtripat108seconds.forthec>>strecentaassandenergyrclcascoutsideccntainocnt

<<>>Lysisacalculation oftheheatupofthecastIroncasesuaspcrfor<<acd.

Therefore, partofthewarglnrepresented lnthethcroeLlsgduetothacastIroncaseshasbeenused.Noucvcr,thafactthatthetransolttcrs havebeentestedto400'Fdoesapplytothesetransolttcrs andprovidesassurance thatthcInstruocnts areLikelytof<<x3ctlon cvcnIfthetcspcrature brieflycxcccdcdthequa'Liflcatlon tccpcrature.

In~dSItlon,intheveryuorstsccnarlo, onlytheInstruacntction assoolstcd ulthrIJPturcd stcac<<Lineendor>>otherstcaxLineuouidbedac>>gcd.Thislsthecasebecausetheates<<senclosures forstc<<aLinesoneandfourexitcental<<vacnt ononeatdaandthestc<<aenclosures forLineatuohandthreeexitIEO'uayontheoppositeaideofthecental<<vacnt.

Therefore tuostcaa(inca3<<1thf<<C3ctloning Instruacntation areavailable tocontroLthecysts<<a<<x3tilltcanbeplacedbnRNRlnthisHorstcasescenario.

Satedonthisandthediscussion above,Itlsccncludcd thataHLEreleaseofthes>>Snit<<xfe oftheLI<<siting casesulthaCHFuouldresultInacceptable cense<<ptnccs

~-(8-APPENDIXB OTALCABLEEVSFSARSection1433Thissectionaddresses theme'chanical forcesfromLOCA,DesignBasisEarthquake (DBE),andcombinedLOCA/DBE.

TheUnit2FSARdocuments theapplicabili.ty ofleakbeforebreaktoCook.Themostreceneanalysesofthistypearedescribed inWCAP11902andtheUnit2,Cycle8RTSR.Theseevenesconsiderapproximately thefirstsecondofehetransient andarenotimpactedbyprotection orsafeguards actuation.

FSARSection1437Thissectionaddresses theoverpressuriration ofthevesselaftercooldown.

TheUFSARmaterialfrom1982appearsnottoaddresstheERGbasedEOP's.ThecurrentmaeerialistheERGbackground material.

TheERGmaterialissymptombased.Actionsrequiredoftheoperatorarebasedontheresultsofananalysisbasedonasteptemperature changeinthecoldleg.Theinitialtemperature waschosentobeaconservatively high550F.Theactionsarethenbasedontheobservedtemperature duringehecourseoftheimplementaeion ofeheEOP's.Theeemperature andpressurearemoni,tored continuously throughoue theapplication oftheEOP'sbystaeustreeF-0.4,Integrity.

(IfoneexceedscurveAofthestaeuscreecriterion, asoaktimeisrequired).

Seep.p.4,8ofF-0.4background andp.5ofFR-P.1background.

BasedonthenatureoftheERGanalysis, thiseventisnoebelievedeobeimpactedbyacommonmodefailureofthenewdigitalequipment.

Thisopinionwasdiscussed withSatyan-Sharma onHov.13,1992.Heconcurred.

FSARection438Thissectiondescribes ananalysistoshowthattheRCSwillnotdepressurize belowtheNzinjection pointfromtheaccumulators priortothetimewhenS.G.coolingisnolongerneededforSBLOCA.Caseswithandwithoutoperatoractionareconsidered.

Thismaterialissuperseded, oratleastmodified, inviewoftheERGbasedEOP's.Operatoractionisprovidedasrequiredforanyeventtoensureisolation oftheaccumulators priortotheinjection ofnitrogenintothereactorcoolantsystem.Atleastthefollowing eventswereaddressed.

(ThestepnumbersareERGnumbersnotEOPnumbers).

LBLOCASBLOCALossofSumpRecirculation SteamBreak/4LoopInadequate CoreCoolingDegradedCoreCoolingE-1ES-1.2ECA-1.1ECA-2.1.ECA-3.1ECA-3'FR-C.1Step28Step23Step12ResponsetoICCFR-C.2ResponsetoDCCStep12LossofRxorSecondary Step1SCoolantPostLOCACooldownandStep23Depressurization LossofEmergency Steps23,31CoolantRecirculation Uncontrolled Steps10,38Depressurization ofallS.G.'sRecoveryModes1'tshouldbenoticedthattheissueismorebroadlyaddressed intheERG'sthanintheUFSAR.TheUFSARcaseswithnooperatorresponseareirrelevant tothisevaluation becauseoperatorresponsemustbeachievedonthelossofnearlyallprotection andsafeguards actuations toachieveasatisfactory outcome.Theoperatoractioncasesaresuperseded bytheERGanalyses.

TheERGdecisiontoisolatetheaccumulators isbasedonobservable parameters andisnotimpactedbyanadditional delayof=1minute.TheERGanalysesinsuppor~ofSBLOCA's(1"break)showthattheaccumulators willbeisolatedonsubcooling notonlowprimarypressure.

Forlargerbreaks,thoseforwhichprimarypressurestabilizes atorbelo~approximately 300psig,theaccumulators areisolatedaftertheaccumulators haveinjected.

Seeresponsenotobtainedforstep15ofE-l.Inconclusion, theERG'saddresstheissueinSection14.3.8morecurrently thantheFSAR.TheERG'saresymptombasedandaddressawiderangeofcontingencies.

Theyarenotdirectlyaffectedbyanadditional delayof~1minuteinobtaining aprotection orsafeguards action.Theyaredesignedinsufficient depthtoprovideassurance thataunitcanbebroughttoasafeandstablecondition following anyaccident.

FSSecton144Thissectionisageneraldescription oftheanalysisofhighenergylinebreaksoutsideofcontainment.

Thematerialinthissectionisfurtherelaborated insections14.4.3through14.4.11.Ahighenergylineisalinewithnormalservicetemperature above200F,anormaloperating pressureabove275psig,andanominaldiametergreaterthan1inch.Fivesystemsweredetermined toincludehighenergylines.Theyare:1)MainSteam2)Feedwater 3)CVCS4)S.G.Blowdown5)SteamtoTDAFPBreaksinhighenergylineswereexaminedfor:1)PipeWhip2)JetImpingement 3)JetErosionofConcrete4)Compartment Pressure-LoadingStress5)Structural Resistance toLoading6)Equipment E.Q.Item3wasdetermined nottobeaproblemingeneral.Breakswereanalyzedforcriteria1,2,4,5,and6.Crackswereanalyzedfor1,2,and6.AnESWfloodincidentisalsoincludedinthissection.Noimpactofthepostulated freeze"oftheFoxborodigitalsoftwareontheseanalysesorthoseofSections14.4.3through14.4.11wasidentifiqd exceptasindicated inthefollowing comments.

FSSection14;43Thissectionaddresses, inageneralway,theabilitytobringthereactortoasafecondition following theeventsevaluated forhighenergylinebreaks.Asindicated onp14.4.3-1oftheUnit1UFSAR,theyaregeneralbecause"itisdeemedappropriate toallowforassessment oftheincidentpriortoiultimately bringingthereactortocoldshutdown".

Mainsteamline breaks'(MSLB) arediscussed insection14.2.5fromthepointofviewofcoreresponseandinsection14.2.7fromthepointofviewofoffsitedoseeffects.MSLBoutsideofcontainment fromthepointofviewofequipment qualification (EQ)isaddressed inUFSARsections14.4.6,14.4.10,and14.4.11.Theevaluation oftheimpactofcommonmodefailure(CMF)ofthenewdigitalequipment onMSLBEQhasbeenplacedinsection14.4.11.

Feedwaterlinebreakwasanalyzedfromthecoreresponsepointofviewinsection14.2.8.TheNKreleasefromafeedlinebreakisbelievedtobesimilarwithorwithoutCMF.Unit2UFSARFigure14.2.8-4suggeststhattheaffectedS.G.blowdownforafeedwater linebreaktakes=200sec.Bythistime,itisbelievedthattheoperatorwillbewellintohisimmediate actions.Steamline isolation isstep12ofE-0.Theoperatorwillcertainly bewellintoimmediate actions,ifthereisaturbinetrip.Ifthereisnoturbinetrip,theturbineisasignificant competitor forsteamfromtheintactsteamgenerators.

Failureofasteamgenerator stopvalvewouldalsonotbeassumedinadditiontothemultiplefailuresoftheCMF.Therefore, blowdownofthemainsteam lineswouldnotoccuraftermanualinitiation ofmainsteamline isolation.

CVCSlinebreakassumesoperatoraction.Thealarmsassumedcontinuetobeavailable fromthecontrolsystem,.andtherefore, arenotaffected.

Thisdescription isnotaffected.

Boththeturbinedrivenauxiliary feedwater pumpandsteamgenerator blowdownlineruptureareconsidered tobesmallsteamline rupturesaccording totheUFSAR.Therefore, theireffectswouldbeexpectedtobeboundedbyMSLBandfeedwater linebreak.Noimpactofthepostulated "freeze"oftheFoxborodigitalsoftwareoneventsotherthanMSLBwasidentified.

SinceMSLBwillbediscussed undersection14.4.11,thesectionisclassified asNA.PSARSecton444Thissectionprovidesthequantitative resultsofstresscalculations forhighenergylinebreaks.Seethediscussion ofSection14.4.2above.FSARSection14.4.5Thissectionprovidessomefurtherelaboration onthepipewhipanalysis.

Seethediscussion ofSection14.4.'2.Notethatthisanalysisusesthemaximumoperating pressureforconservatism.

FSARSecton14.46thepressure~analysisoutsideThepressurepeaksappearintheanincreaseintimeuntilreactorthissectionisclassified asnotThissectionprovidesfurtherdetailsoncontainment duetoahighenergylinebreak.firstsecondortwoandcannotbeimpactedbytrip.Therefore, thepressurepeakaspectofapplicable.

Temperature peaksare=5minutesintotheeventpresumably duetoheatsinks.Theimpactofsteamgenerator superheat fromaMSLBoutsidecontainment onequipment qualification isaddressed inthissection.Withoutautomatic safeguards functions, theenvironmental conditions couldpotentially beworse.

Theequipment qualification aspectofthissectioniscombinedwithSection14.4.11whereevent+whichimpactenvironmental conditions andwhicharemi~iga~ed byprotection andsafeguards actuations arediscussed.

Theseeventsaremassandenergyreleaseinsideandoutsidecontainment.

FSARSection1447Thissectionprovidessomefurtherelaboration onthejetimpingement analysis.

Italsousesthemaximumoperating pressure.

Seethediscussion ofSection14.4.2.FSecton1448Thissectiondescribes theimpactofhighenergylinebreaksonthecontainment exterior.

Seethediscussion ofSection14.4.2.~~-FSARSection1449Thissectiondescribes themodifications requiredbythehighenergylineanalysis.

ItwillnotbeaffectedbytheFoxboro"freeze".

FARSection440Thissectiondescribes thestepstakento'nsurethatthe'dverse environmental conditions thatresultfromHELBdonotinhibittheabilitytobringthereactortocoldshutdown.

Withoutautomatic safeguard functions, theemrironmental conditions couldpotentially beworse.ThissectioniscombinedwithSection14.4.11'here eventswhichimpactenvironmental conditions andwhicharemitigated byprotection andsafeguards actuations arediscussed.

Theseeventsaremassandenergyreleaseinsideandoutsidecontainment.