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{{#Wiki_filter: | {{#Wiki_filter:ATTACHMENT 2TOAEP'NRC'1213A EXISTINGTECHNICAL SPECIFICATION PAGESMARKEDTOREFLECTPROPOSEDCHANGES9510310312 951020PDRADOCK05000315PPDR 0 | ||
34.7SYSTEMS347.TGRBTNECYCLESAFETYVALVESNGCONDXTONFOROPERAON3.7.1. | 34.7SYSTEMS347.TGRBTNECYCLESAFETYVALVESNGCONDXTONFOROPERAON3.7.1.1Allmainsteamlinecodesafetyvalvesassociated witheachsteamgenerator shallbeOPERABLE. | ||
'TABLE3.7- | ancC.v~lu~is>a~a.4With4reactorcoolantloopsandassociate steamgenerators in'perationpand withoneormoremainsteam1necodesafetyvalvesinop'arable, operation | ||
/41VV< | ,naproceedprovidethatwithin4hours,eithertheinoperable restoredtoOPlZstatus'rthePowerRangeNeutronFluxHighSetpointtripisreduced.perTable3.7-1;otherwise, beinae:-4e~HOTSTANDBYwithinthenext6hoursand.comply~~a@So%56cAAthA b.b.(Wi3reactorcoolantloopsandassociated steamgenerators inperation~ | ||
34.7PLANTSYSTEMS34.7.1XNECYCLESFVALVESNGCONDONFOOPERAON3.7.1. | andwithoneormoremainsteamlinecodesafetyvalvesassociated withanoperating loopinoperable, operation 4MGMMnayproceedprovidedg thatnirhin4honte,eitherthein'operable | ||
<~"+i~C~~s.restored toOPERABLEstatus~orthereactortripbreakersareopened;otherwise, bein~SHUTDOWNwithintheNext30hours.Hol-Theprovisions ofSpecification 3.0.4arenotapp1.$cable.SURVEXLLANCE REUIREMENTS 4.7.1.1.Eachmainsteamlinecodesafetyvalveshallbedemonstrated OPERABLE'naccordance withSpecification 4.0.5andwithliftsettingsasshowninTable4.7-1.Thesafetyvalveshallberesettothenominalvalue~1Xwheneverfoundoutsidethe+1Ktolerance. | |||
qg~po,s-,~S ogSq~Q~Otee~i~Wk>M.3~COOKNUCLEARPLANT-UNlT13/47-1~HENTNO.k@0,464 | |||
'TABLE3.7-lHAXlHUHALLOWABLE POllERRAHGENEUTRONFLUXlllGIISETPOIHTMITllIHOPERAOLE STEAHEPIE~I'IKTEEEEPEPEIEWIE | |||
~HaxinemtiumberofInoperable SafetyValvesonAnOeratinSteamGenerator HaximumAllowable PowerRangetleutronFluxilighSetpointPercentofRATEDTHERHALPOWER4I~~ | |||
/41VV<TheOPERABILITY ofthemainsteamlinecodesafetyvalvesensureschatthesecondary systempressurewillbelimitedcowt.thini.csdesignpressureof1085psigduringthemostsevereanticipated systemopera-tionalcransient. | |||
Themaximumrelievt.ng capacityisassociated wichacurbinetripfrom100%RATEDTHER.fALPOMERcoincident withanassumedlossofcondenser heatsink(i.e.,nosceambypasscothecondenser). | |||
Thespecified valveli.ftsettingsandrelieving capacities areinaccordance withtherequirements ofSectionIIIofcheASMEBoi.lerandPressureCode,1971Edition.Thetotalrelieving capacicyforallvalvesona11ofthe'steamli.nesis17,153,800 lbs/hrwhichisapproximately 121percentofthetocalsecondary steamflowof14,120,000 lbs/hrac100%RATEDTHERMALPOMER.Aminimumof2OPERABLEsafecyvalvesperoperabLesteamgenerator ensuresthatsufficient relievt.ng capacityi.savailable forcheallo~able THER.'iAL POWERrestri.ction inTable3.7-1.STARTUPand/orPOMEROPERATION inoperable withinthelimitations ofofchereduction insecondary systembythereducedreactortripseccingschannels. | |||
Thereactortripsetpoincfollowing bases:isallowable withsafetyaalvestheACTIONrequiremencs onthebasissteamflowandTHLq.KLPOt:ERrequiredofthePowerRangeNeutronFluxreductions arederivedonthe.SPx(109)'XFor4loopoperaci.on Qplam..a.Harkr8%here:SPreducedreacctripsetpoinj.npercencofRATEDTHERMALPOPERVmaximumnumberofinablesafecyval.vespersceamline<<1,2or3.X-Totalreli.ev'ng capacityofalsafecyvalvespersteamline48,450lbs/hour. | |||
YNaxumrelieving capacityofanyonesecyvalve57,690lbs/hour. | |||
(10PowerRangeNeutronFlux-High TripSecpoincforloopoperaci.on. | |||
D.C.COOK-UNIT1B3/47-1AHENDHENT NO.120 Relacementtextfor3/4.7.1.1 BasesHi<5=(100/Q)(4wpgZwhere:HiC=SafetyAnalysispowerrangehighneutronfluxsetpointinpercentQ=NominalNSSSpowerratingoftheplant(including reactorcoolantpumpheat)inMwtK=Conversion factor,947.82Q3tu/~Sec Mwtw,=Minimumtotalstcamflowratecapability oftheoperableMSSVsonanyonesteamgenerator atthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate, inlb/sec.Forexample,ifthemaximumnumberofinoperable MSSVsonanyonesteamgenerator isone,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating | |||
: pressure, excluding thehighestcapacityMSSV.Ifthemaximumnumberofinoperable MSSVspersteamgenerator isthree,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating | |||
: pressure, excluding thethreehighestcapacityMSSVs.h,,=Heatofvaporization forsteamatthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate inBtu/ibm4=NumberofloopsinplantThevaluescalculated fromthisalgorithm arethenadjustedlowerforuseinTechnical Specification 3.7.1.1toaccountforinstrument andchanneluncertainties by9%.Thisreducesthemaximumplantoperating powerlevelsothatitislowerthanthereactorprotection systemsetpointbyanappropriate operating margin. | |||
34.7PLANTSYSTEMS34.7.1XNECYCLESFVALVESNGCONDONFOOPERAON3.7.1.1Allnsdnsteanlinecodesafetyvalvesssscclated vdeheachsteangenerator shallbeOPERABLE. | |||
APPLXCABXLX Y:Modes1,2and3.~OTXON:moog'.CZ: | |||
Valve@o~a.Wi.th4reactorcoolantloopsandassociate steamgenerators inoperation andwithoneormoremainsteam1necodesafetyvalvesinoperablL, operation maproceedprovidedg thatwithin4hours,eithertheinoperable restoredtoOPLEstatus>orthePowerRangeNeutronFluxHigh'ipetpoint'sreducedperTable3.7-1;otherwise, beinae-~~HOTSTANDBYwithinthenext6hoursand.Complot,40~clog~~4~ta4S.b.4Wi3reactorcoolantloopsandassociated steamgenerators in'perationyand withoneormoremainsteamlinecodesafetyvalvesassociated withanoperating loopinoperable, operation | |||
~BOYImayproceedprovidedg thatwithin4hours,eitherthe'noperable V<QclS)oVC | |||
~o-kerestoredtoOPERABLEstatus/or thereactortripbreakersareopened;otherwise, beinCGASHUTDOWNwithinthe'ext30hours.HoT'-Theprovisions'f Specification 3.0.4arenotapplicable. | |||
SURVEXLLANCE REEMENTS4.7.1..1Eachmainsteamlinecodesafetyvalveshallbedemonstrated OPERABLEinaccordance withSpecification 4.0.5andwithliftsettingsasshowninTable4.7-1.Thesafetyvalveshallberesettothenominalvaluepl%whenever foundoutsidethe+1Ktolerance. | |||
~P~g,sy~gQQ~>Q,~~9.0.9o~VO+aPP4cab4~f~iceieiODE3.COOKNUCLEARPLANT-UNIT.23/47-1AMENDMENT NO.Sa,167 TABLE3-1LLOWABLEOWNGEEURONGHSETPOINTWITINOPERABLE SESAFVALVESDURING4LOOPOPERA0MaximumNumberofInoperable SafetyValveso0eatnSteamGenerator MaximumAllowable PowerRangeNeutronFluxHighSetpointPercentoRATEDERMALPOWECOOKNUCLEARPLANT-UNIT23/CI.7-2 34.7PIANTSYSTEMSBASES34.7.1TURBINECYCLE34.7.1.1SAFETYVALVESTheOPERABILITY ofthemainsteamlinecodasafetyvalvesensureschacthesecondary systempressurevillbelimitedtovithin110iofi,tsdesignpressureof1085psigduringthemostsevereanticipated systemoperational czansient. | |||
Th>>maximumreueving'capacity isassociated vithacuzbinetzipfrom100%RATEDTHERMALPOMERcoincident vithanassumedlossofcondensez heatsink(i.e.,nosteambypasstothecondenser). | |||
Thespecified valveltfcsettingsandrelieving capacities areinaccordance vithcherequirements ofSectionIIIoftheASMEBoilerandPressureCode,1971Edition.Thetotalrelievtng capacityofallsafetyvalvesonallofthesteamlinesis17,153,800 lbs/hrvhichisatleast105percentofthemaximumsecondary steamflovrateat100%RATEDTHERMALPOVER.hminimumof2OPERABLEsafetyvalvespersteamgenerator ensuresthatsufficient relieving capacityisavailable forcheallovable THERMALPOVERrestriction inTable3.7-1.STARTUPand/orPOVKROPERATION isallovable vichsafetyvalvesinoperable vithinthelimitacions oftheACTIONrequirements onthebasisofthereduction insecondary syscemsteamflovandTHERMALPOMrequt.red bythereducedreactortripsettingsofthePoverRangeNeutronFluxchannels. | |||
Thereactortripsetpotntreductions arederivedonthefolloving bases:For4loopoperation Where:SPreducedreactzipsecpointinperntofRATEDTHECALPOVER@pe~a.~hahVmaximumnumberofinope~safetyvalvespersteamlineXtotalrelievtncapacityofallstyvalvespezsteamlineinlbours4,2&8,450 Ymaxrelieving capacityofanyonesafealvelbs./hour 857,6909PoverRangeNeutronFlux-High TripSecpointfor4loopoperation COOKNUCLEARPLANT-UNIT2B3/47-1AMENDMENT NO.Sl.134 Relacementtextfor3/4.7.1.1 BasesHil=(100/Q)~(4)vh)Kwhere:Hi4=Safe@Analysis powerrangehighneutronfluxsetpointinpercentQ=NomaalNSSSpowerratingoftheplant(including reactorcoolantpumpheat)inMwtK=Contortion factor,947.82~Bto/SecMwtw,=Mimmxmtotalsteamflowratecapability oftheoperableMSSVsonanyonesteamgenerator atthehighestMSSI'opening pressureincluding tolerance andaccumulation, asappropriate, inIb/sec.Forexample,iftheaazimumnumberofinoperable MSSVsonanyonesteamgenerator isone,thenw,shouldbeasumnarion ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating | |||
: pressure, exclaKagthehighestcapacityMSSV.Ifthemaximumnumberofinoperable MSSVspersteamgenerator isthm-thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMS'perating | |||
: prcssure, excluding thethreehighestcapacityMSSVs.h<<=Heateiivaporization forsteamatthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappepriate inBtu/IbmI4=Numb'floopsinplantThevaluesahalatedfromthisalgorithm arethenadjustedlowerforuseinTechnical Specification 3.7.1.1toaccountforjumentandchanneluncertainties by9%.Thisrcduccsthcmaximumplantoperating powerlevelsothatitisloserthanthereactorprotection systemsetpointbyanappropriate operating margin. | |||
ATTACHMENT 3TOAEP:NRC:1213A PROPOSEDREVISEDTECHNICAL SPECIFICATION PAGES 3/4LIMITINGCONDlTIONS FOROPERATION ANDSURVEILLANCE REQUIREMENTS 3/4.7PLANTSYSTEMS3/4.7.1TURBINECYCLESAFETYVALVESLIMITINGCONDITION FOROPERATION 3.7.1.1Allmainsteamlinecodesafetyvalvesassociated witheachsteamgenerator shallbeOPERABLE. | |||
APPLICABILITY: | |||
MODES1,2and3.ACTION:aoMODES1&2:With4reactorcoolantloopsandassociated steamgenerators inoperation, andwithoneormoremainsteamlinecodesafetyvalvesinoperable, operation mayproceedprovidedthatwithin4hours,eithertheinoperable valve(s)arerestoredtoOPERABLEstatus,orthePowerRangeNeutronFluxHighSetpointtripisreducedperTable3.7-1;otherwise, beinHOTSTANDBYwithinthenext6hoursandcomplywithactionstatement b.b.MODE3:Withaminimumof3reactorcoolantloopsandassociated steamgenerators inoperation, andwithoneormoremainsteamlinecodesafetyvalvesassociated withanoperating loopinoperable, operation mayproceedprovidedthatwithin4hours,eithertheinoperable valve(s}atbrestoredtoOPERABLEstatus,orthereactortripbreakersareopened;otherwise, beinHOTSHUTDOWNwithinthenext30hours.Theprovisions ofSpecification 3.0.4arenotapplicable. | |||
SURVEILLANCE REUIREMENTS 4.7.1.1Eachmainsteamlinecodesafetyvalveshallbedemonstrated OPERABLEinaccordance withSpecification 4.0.5andwithliftsettingsasshowninTable4.7-1.Thesafetyvalveshallberesettothenominalvalue+1%wheneverfoundoutsidethe+1%tolerance. | |||
4.7.1.2Theprovisions ofSpecification | |||
3/4' | ==4.0. 4arenotapplicable== | ||
forentryintoMODE3.COOKNUCLEARPLANT-UNIT 1Page3/47-1AMENDMENT 420,444,4' 3/4LIMITINGCONDITIONS FOROPERATION ANDSURVEILLANCE REQUIREMENTS 3/4.7PLANTSYSTEMSTABLE3.7-1MAXIMUMALLOWABLE POWERRANGENEUTRONFLUXHIGHSETPOINTWITHINOPERABLE STEAMLINESAFETYVALVESDURING4LOOPOPERATION MaximumNumberofInoperable SafetyValvesonAn0eratinSteamGenerator MaximumAllowable PowerRangeNeutronFluxHighSetpoint(PercentofRATEDTHERMALPOWER)65.146.528.0COOKNUCLEARPLANT-UNIT 1Page3/47-2 3/4.nBASES3/4.7PLANTSYSTE<MS3/4.7.1TURBINECYCLE3/4.7.1.1 SAFETYVALVESTheOPERABILITY ofthemainsteamlinecodesafetyvalvesensuresthatthesecondary systempressurewillbelimitedtowithin110%ofitsdesignpressureof1085psigduringthemostsevereanticipated systemoperational transient. | |||
Themaximumrelieving capacityisassociated withaturbinetripfrom100%RATEDTHERMALPOWERcoincident withanassumedlossofcondenser heatsink(i.e.,nosteambypasstothecondenser). | |||
Thespecified valveliftsettingsandrelieving capacities areinaccordance withtherequirements ofSectionIIIoftheASMEBoilerandPressureCode,1971Edition.ThesafetyvalveisOPERABLEwithaliftsettingofJ3%aboutthenominalvalue.However,thesafetyvalveshallberesettothenominalvalueJ1%wheneverfoundoutsidetheJ1%tolerance. | |||
Thetotalrelieving capacityforallvalvesonallofthesteamlinesis17,153,800 lbs/hrwhichisapproximately 121percentofthetotalsecondary steamflowof14,120,000 Ibs/hrat100%RATEDTHERMALPOWER.Aminimumof2OPERABLEsafetyvalvesperoperablesteamgenerator ensuresthatsufficient relieving capacityisavailable fortheallowable THERMALPOWERrestriction inTable3.7-1.STARTUPand/orPOWEROPERATION isallowable withsafetyvalvesinoperable withinthelimitations oftheACTIONrequirements onthebasisofthereduction insecondary systemsteamflowandTHERMALPOWERrequiredbythereducedreactortripsettingsofthePowerRangeNeutronFluxchannels. | |||
Thereactortripsetpointreductions arederivedonthefollowing bases:ffso=iannfffi~r(4w&Kwhere:Hi4=SafetyAnalysispowerrangehighneutronfluxsetpointinpercentQ=K=hfNominalNSSSpowerratingoftheplant(including reactorcoolantpumpheat)inMwtConversion factor,947.82~Btu/SecMwtMinimumtotalsteamflowratecapability oftheoperableMSSVsonanyonesteamgenerator atthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate, inlb/sec.Forexample,ifthemaximumnumberofinoperable MSSVsonanyonesteamgenerator isone,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating | |||
: pressure, excluding thehighestcapacityMSSV.Ifthemaximumnumberofinoperable MSSVspersteamgenerator isthree,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating | |||
: pressure, excluding thethreehighestcapacityMSSVs.Heatofvaporization forsteamatthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate inBtu/ibm4=NumberofloopsinplantThevaluescalculated fromthisalgorithm arethenadjustedlowerforuseinTechnical Specification 3.7.1.1toaccountforinstrument andchanneluncertainties by9%.Thisreducesthemaximumplantoperating powerlevelsothatitislowerthanthereactorprotection systemsetpointbyanappropriate operating margin.COOKNUCLEARPLANT-UNIT 1PageB3/47-1AMENDMENT 420 | |||
3/4'IMITINGCONDITIONS FOROPERATION ANDSURVEILLANCE REQUIREMENTS 3/4.7PLANTSYSTEMS3/4.7.1TURBINECYCLESAFETYVALVESLIMITINGCONDITION FOROPERATION 3.7.1.1Allmainsteamlinecodesafetyvalvesassociated witheachsteamgenerator shallbeOPERABLE. | |||
APPLICABILITY: | |||
MODES1,2and3.ACTION:MODES1&2:With4reactorcoolantloopsandassociated steamgenerators inoperation, andwithoneormoremainsteamlinecodesafetyvalvesinoperable, operation mayproceedprovidedthatwithin4hours,eithertheinoperable valve(s)arerestoredtoOPERABLEstatus,orthePowerRangeNeutronFluxHighSetpointtripisreducedperTable3.7-1;otherwise, beinHOTSTANDBYwithinthenext6hoursandcomplywithactionstatement b.b.MODE3:Withaminimumof3reactorcoolantloopsandassociated steamgenerators inoperation, andwithoneormoremainsteamlinecodesafetyvalvesassociated withanoperating loopinoperable, operation mayproceedprovidedthatwithin4hours,eithertheinoperable valve(s)arerestoredtoOPERABLEstatus,orthereactortripbreakersareopened;otherwise, beinHOTSHUTDOWNwithinthenext30hours.c.Theprovisions ofSpecification 3.0.4arenotapplicable. | |||
SURVEILLANCE REUIREMENTS 4.7.1.1Eachmainsteamlinecodesafetyvalveshallbedemonstrated OPERABLEinaccordance withSpecification 4.0.5andwithliftsettingsasshowninTable4.7-1.Thesafetyvalveshallberesettothenominalvalue+1%wheneverfoundoutsidethe+1%tolerance. | |||
4.7.1,2Theprovisions ofSpecification | |||
==4.0. 4arenotapplicable== | |||
forentryintoMODE3.COOKNUCLEARPLANT-UNIT 2Page3/47-1 3/4LIMITINGCONDITIONS FOROPERATION ANDSURVEILLANCE REQUIREMENTS 3/4.7PLANTSYSTEMSTABLE3.7-1MAXIMUMALLOWABLE POWERRANGENEUTRONFLUXHIGHSETPOINTWITHINOPERABLE STEAMLINESAFETYVALVESDURING4LOOPOPERATION MaximumNumberofInoperable SafetyValvesonAnyOperating SteamGenerator MaximumAllowable PowerRangeNeutronFluxHighSetpoint(PercentofRATEDTHERMALPOWER)61.643.926.2COOKNUCLEARPLANT-UNIT 2Page3/47-2AMENDMENT 3/4'ASES3/4.7PLANTSYSTEMS3/4.7.1TURBINECYCLE3/4.7.1.1 SAFETYVALVESTheOPERABILITY ofthemainsteainlinecodesafetyvalvesensuresthatthesecondary systempressurewill'belimitedtowithin110%ofitsdesignpressureof1085psigduringthemostsevereanticipated systemoperational transient. | |||
Themaximumrelieving capacityisassociated withaturbinetripfrom100%RATEDTHERMALPOWERcoincident withanassumedlossofcondenser heatsink(i.e.,nosteambypasstothecondenser). | |||
Thespecified valveliftsettingsandrelieving capacities areinaccordance withtherequirements ofSectionIIIoftheASMEBoilerandPressureCode,1971Edition.ThesafetyvalveisOPERABLEwithaliftsettingof+3%aboutthenominalvalue.However,thesafetyvalveshallberesettothenominalvalueJ1%wheneverfoundoutsidethe+1%tolerance. | |||
Thetotalrelieving capacityofallsafetyvalvesonallofthesteamlinesis17,153,800 lbs/hrwhichisatleast105percentofthemaximumsecondary steamflowrateat100%RATEDTHERMALPOWER.Aminimumof2OPERABLEsafetyvalvespersteamgenerator ensuresthatsufficient relieving capacityisavailable fortheallowable THERMALPOWERrestriction inTable3.7-1.STARTUPand/orPOWEROPERATION isallowable withsafetyvalvesinoperable withinthelimitations oftheACTIONrequirements onthebasisofthereduction insecondary systemsteamflowandTHERMALPOWERrequiredbythereducedreactortripsettingsofthePowerRangeNeutronFluxchannels. | |||
Thereactortripsetpointreductions arederivedonthefollowing bases:ffsto=taooft2t | |||
~r(4w&z)Kwhere:Hi4=SafetyAnalysispowerrangehighneutronfluxsetpointinpercentQ=NominalNSSSpowerratingoftheplant(including reactorcoolantpumpheat)inMwtK=Conversion factor,947.82~Bto/SecMwtw,=Minimumtotalsteamflowratecapability oftheoperableMSSVsonanyonesteamgenerator atthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate, inlb/sec.Forexample,ifthemaximumnumberofinoperable MSSVsonanyonesteamgenerator isone,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating | |||
: pressure, excluding thehighestcapacityMSSV.Ifthemaximumnumberofinoperable MSSVspersteamgenerator isthree,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating | |||
: pressure, excluding thethreehighestcapacityMSSVs.h<<=Heatofvaporization forsteamatthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate inBtu/ibm4=NumberofloopsinplantThevaluescalculated fromthisalgorithm arethenadjustedlowerforuseinTechnical Specification 3.7.1.1toaccountforinstrument andchanneluncertainties by9%.Thisreducesthemaximumplantoperating powerlevelsothatitislowerthanthereactorprotection systemsetpointbyanappropriate operating margin.COOKNUCLEARPLANT-UNIT 2PageB3/47-1AMENDMENT 82,434 0I ATTACHMENT 4TOAEP:NRC:1213A WESTINGHOUSE NSAL94-001"OPERATION ATREDUCEDPOWERLEVELSWITHINOPERABLE MSSV'S" I | |||
Westinghouse EnergySystemsBusinessUnitNUCLEARSAF1TYADVISORYLETTER'HISISANOTIHCATION OFARECENTLYIDENTIFIED POTENTIAL SAFETYISSUEPERTAINING TOBASICCOMPONENTS'UPPLIED BYWESTINGHOUSE. | |||
THISINFORMATION ISBEINGPROVIDEDTOYOUSOTHATAREVIEWOFTHISISSUECANBECONDUCEDBYYOUTODETERMINE IFANYACTIONISREQUIRED. | |||
P.O.Box355,Pittsburgh, PA152304355 | |||
==Subject:== | ==Subject:== | ||
Operation atReducedPowerLevelswithInoperable MSSVsNumbet:NSAL-944)01 BasicComponent: | |||
LossofLoadfi'urbinc TripAnalysisforPlantLicensing BasisDatesOII20$4Plants:SecEnclosedListSubstantial SafetyHazardorFailuretoComplyPursuantto10CFR21.21(a)TransferofInformation Pursuantto10CFR21.21(b)AdvisoryInformation Pursuantto10CFR21.21(c)(2) | |||
SUMMARYYesCiNotlYcs0Ycs0Westinghouse hasidentified apotential safetyissueregarding plantoperation withinTechnical Specification Table3.7-1.Thisissuedoesnotrepresent asubstantial safetyhazardforyourplantpursuantto10CFR21.However,thisissuedoesrepresent acondition whichmayimpactyourplant'slicensing basis.ITable3.7-1allowsplantstooperatewithareducednumberofoperableMSSVsatareducedpowerlevel,asdetermined bythehighneutronQuxtripsetpoint. | |||
ThcFSARlossofload/turbine trip(LOIJIT)analysisfromfullpowerboundsthecasewhereailMSSVsareoperable. | |||
TheFSAR(LOLfIT)eventmaynotbeboundingfortheallowable operating configurations ofTable3.7-1sincethehighneutronfiuxtripsetpojnt, whichisidentified inTable3.7-1foracorresponding numberofinoperable MSSVs,maynotbelowenoughtoprecludeasecondary sideoverpressurization condition. | |||
Asaresult,thebasisforTable3.7-1maynotbesuQicient toprecludeoveipressurization ofthesecondaty sideofthesteamgenerator. | |||
'Therefore, itisrecommended thatyoureviewtheenclosedinformation todeterinine thcapplicability ofthisissuetoyourplant.Theenclosedinfortnation containsamoredetaileddescription oftheissueandidentifies solutions thatyoumaywishtopursuetoaddressthisissue.Thesesolutions include,butarenotlimitedto,areevaluation oftheLOIJITanalysisand/orachangeto~Technical Specification Table3.7-1.Additional information, ifrequired, maybeobtainedfromthcoriginator. | |||
Tclephonc 412-3746460. | |||
Originator. | |||
.W.FasnachtStrategic Licensing IssuesH.A.Scpp,Manager,Strategic Licensing Issuesa%418.wpf: | |||
1b412094 | |||
PlantsAffectedD.C.Cook1&2J.M.FarleyI&2Byron1& | PlantsAffectedD.C.Cook1&2J.M.FarleyI&2Byron1&2Braidwood I&2V.C.SummerIZion1&2ShearonHarrisIW.B.McGuireI&2CatawbaI&2BeaverValleyI&2TurkeyPoint3&4VogtleI&2IndianPoint2&3SeabrookIMillstone 3DiabloCanyonI&2WolfCreekCallawayIComanchePeakI&2SouthTexasI&2SequoyahI&2NorthAnnaI&2WattsBarI&2Size,well BKori1,2,3 | ||
&4Yonggwang I&2SalemI&2@%418.wpf:1b411994 II 04 IssueDescritionWestinghouse hasidentified adeficiency inthebasisforTechnical Specification 3.7.1.1.ThisTechnical Specification allowstheplanttooperateatareducedpowerlevelwithareducednumberofoperableMainSteamSafetyValves(MSSVs).Thedeficiency isintheassumption thatthemaximumallowable initialpowerlevelisalinearfunctionoftheavailable MSSVreliefcapacity. | |||
Thelinearfunctionisidentified intheBasesSectionforTechnical Specification 3/4.7.1.1 andisprovidedasfollows:Sp=(X)aO(V)x(i(e)XSP=Reducedreactortripsetpointin%ofRATEDTHERMALPOWERV=Maximumnumberofinoperable safetyvalvespersteamlineX=Totalrelieving capacityofallsafetyvalvespersteamlineinibm/hour(109)=Maximumrelieving capacityofanyonesafetyvalveinIbm/hourPowerrangeneutronflux-high tripsetpointforallloopsinoperation Undercerfainconditions andwithtypicalsafetyanalysisassumptions, aLossofLoad/Drrbine Triptransient frompart-power conditions mayresultinoverpressurization ofthemainsteamsystemwhenoperWnginaccordance withthisTechnical Specification. | |||
'Ihefollowing discussion describes theissueinmoredetailandprovidesrecommended alternatives foraddressing theissue.Technical Evaluation | |||
'IheLossofLoad/Turbine Trip(LOLGT)eventisanalyzedintheFSARtoshowthatcorepro~onmarginsaremaintained (DNBR),theRCSwillnotoverpressurize, andthemainsteamsystemwillnotoveipressurize. | |||
Theanalysisassumesanimmediate lossofsteamrelieving capability throughtheturbineandcoincident lossofallmainfeedwater. | |||
Nocreditistakenforthedirectreactortriponturbinetrip,sincethistripwouldnotbeactuatedforthecaseofalossofsteamload.Rather,thetransient isterminated byareactortriponhighpressurizer | |||
: pressure, overtemperature AT,orlowsteamgenerator waterlevel.Secondary sideov'erpressure protection isprovidedbyactuation oftheMainSteamSafetyValves(MSSVs),whicharedesignedtorelieveatleastfullpowernominalsteamflow.'IlieanalysisverifiesthattheMSSVcapacityissufficient topreventsecondary sidepressurefimm.exceeding 110percentofthedesignpressure. | |||
0%418.vq>f:tb411994 | |||
TheFSARonlyanalyzestheLOIJITtransient GomtheMpowerinitialcondition, withcasesexamining theeffectsofassumingprimarysidepressurecontrolanddifferent reactivity feedbackconditions. | |||
Withfullyoperational MSSVs,itcanbedemonstrated thatoverpressure protection isprovidedforallinitialpowerlevels.However,formostplants,Technical Specification 3.7.1.1allowsoperation withareducednumberofoperableMSSVsatareducedpowerlevelasdetermined byresetting thepowerrangehighneutronfiuxsetpoint. | |||
ThisTechnical Specification isnotbasedonadetailedanalysis, butratherontheassumption thatthemaximumallowable initialpowerlevelisalinearfunctionoftheavailable MSSVreliefcapacity. | |||
: Recently, ithasbeendetermined thatthisassumption isnotvalid.'Iheproblemisthatifmainfeedwater islost,areactortripisnecessary topreventsecondary sideoverpressurization forallpostulated coreconditions. | |||
Athighinitialpowerlevelsareactortripisactuatedearlyinthetransient as.aresultofeitherhighpressurizer pressureorovertemperature hT.Thereactortripterminates thetransient andtheMSSVsmaintainsteampressurebelow110%ofthedesignvalue.Atlowerinitialpowerlevelsareactortripmaynotbeactuatedearlyinthetransient. | |||
Anovertempeiature hTtripisn'tgenerated sincethecorethermalmarginsareincreased atlowerpowerlevels.Ahighpressurizer pressuretripisn'tgenerated iftheprimarypressurecontrolsystemsfunctionnormally. | |||
Thisresultsinalongertimeduringwhichprimaryheatistransferred tothesecondary side.'Ihereactoreventually, tripsonlowsteamgenerator waterlevel,butthismaynotoccurbeforesteampressureexceeds110%ofthedesignvalueifoneormoreMSSVsareinoperable inaccordance withtheTechnical Specification. | |||
Duetothewidevarietyofplantdesignfeaturesthatareimportant totheLOIJITanalysis, itisdifficult toperformagenericevaluation toshowthattheissuedoesnotapplytocertainplants.Thefollowing keyparameters haveasignificant effectonthesecondary sidepressuretransient MSSVreliefcapacityModerator Temperature Coefficient (MTC)MarginbetweentheMSSVsetpressures (including tolerance) andtheoverpressure limitLow-lowsteamgenerator waterlevelreactortripsetpointSafetSinificance TheTechnical Specifications formostplantsallowoperation atareducedpowerlevelwithinoperable MSSVs.Fromalicensing basisperspective, thiscondition mayresultinsecondary sideoverpressurization intheeventofaLOIJITtransient. | |||
Thelicensing basisforanticipated operational occurrences (ANSCondition IIevents)typically requiresthatthesecondary sideprcssureremainbelow110%ofthedesignvalue.a%418.wpf: | |||
Ib411994 Westinghouse hasdetermined thatthisissuedoesnotrepresent asubstantial safetyhazard.Thereareseveralmitigating factorswhichprovideassurance thatthereisnolossofsafetyfunctiontotheexteatthatthereisamajorreduction inthedegreeofprotection providedtothepublichealthandsafety.Theseinclude,butarenotlimitedto,thefollowing: | |||
1.Adequateoverpressure protection isprovidedatallpowerlevelsifalloftheMSSVsareoperable. | |||
2.Ifareactortripdoesnotoccurbutmainfeedwater fiowismaintained, operation inaccordance withtheTechnical Specification Table3.7-1willnotresultinanoverpressure condition. | |||
3.InanyLOIJITtransient, theatmospheric steamdumpvalvesand/orcondenser steamdumpvalvesactuatetorelieveenergyiromthesteamgenerators priortotheopeningoftheMSSVs,andcontinuetorelievesteamiftheMSSVsdoopen.Sinceitisnotasafety-grade | |||
: function, steamdumpisnotassumedtooperateinthesafetyanalysis; however,inrealityitisthefirstlineofdefenseinprotecting thesecondary systemagainstoverpressurizatioa. | |||
Itisveryimprobable thatallthesecompoaents wouldbeinoperable coincident withinoperable MSSVs.4.Evennearthebeginning ofcorelifewithapositiveorzeroMTC,theprimaryvolantheatupresulting fromthetransient wouldtendtodrivethehGCnegative, whichwould.reducethecorepoweraadheatinputtothecoolaat.Thiswouldresultin'alowerrequiredMSSVcapacitytopreventsecondary ovegressurization. | |||
Thesafetyanalysisdoesnotcreditthereduction ofMTCduringthetransient. | |||
NRCAwareness IReortabilit Westinghouse hasnotnotifiedtheNRCofthisissue,baseduponthedetermination thatitdoesaotrepresent asubstantial safetyhazardpursuantto10CFR21.However,Westinghouse willsendacopyofthislettertotheNRCsincethisissueimpactsinformation contained inNUREG-1431, "Standard Technical Specifications, Westinghouse Plants".Recommendations Toaddressthisissue,thefollowing actionsmaybeconsidered: | |||
(1)ModifyTechaical Specificatioa 3.7.1.1(orequivalent) andtheassociated basissuchthatthemaximumpowerlevelallowedforoperation withinoperable MSSVsisbelowtheheatremovingcapability oftheoperableMSSVs.Aconservative waytodothisistosetthepowerrangehighaeutmnfiuxsetpointtothispowerlevel,thusensuringthattheactualpowerlevelcannotexceed@%418.wpf:1b411994 | |||
~~thisvalue. | ~~thisvalue.Tocalculate thissetpoint, thegoverning equationistherelationship q=mhh,whereqistheheatinputfmmtheprimaryside,misthesteamflowrateandhhistheheatofvaporization atthesteamreliefpressure(assuming nosubcooled fecdwater). | ||
~y~0C~c. | Thus,analgorithm foruscindefiningtherevisedTechnical Specification tablesetpointvalueswouldbe:Hig=(100/Q)~(wPN)Kwhere:'ig=SafetyAnalysispowerrangehighneutronfluxsetpoint, percentQ=NominalNSSSpowerratingoftheplant(including reactorcoolantpumpheat),MwtK=Conversion factor,947.82MwtwsMinimumtotalsteamlowratecapability oftheoperableMSSVsonanyonesteamgenerator atthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate, inib/sec.Forexample,ifthemaximumnumberofinoperable MSSVsonanyonesteamgenerator isone,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating | ||
: prcssure, excluding thehighestcapacityMSSV.Ifthemaximumnumberofinoperable MSSVsperstcamgenerator isthreethenw,shouldbeasummation ofthecapacityofthcoperableMSSVsatthehighestoperableMSSVoperating | |||
: prcssure, excluding thethreehighestcapacityMSSVs.h+=heatofvaporization forstcamatthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate, Btu/1bmN=Numberofloopsin plantThevaluescalculated fromthisalgorithm mustthenbeadjustedlowerforuscinTechnical Specification 3.7.1.1toaccountforinstrument andchanneluncertainties (typically 9%power).Themaximumplantoperating powerlevelwouldthenbelowerthanthereactorprotection systemsetpointbyanappropriate operating margin.0%418.wpf: | |||
1b411994 kk | |||
~y~0C~c.Itshouldbenotedthattheuscofthisequatioawillresolvetheissueideatified inthisletterbyeaablingyoutore~culate yourTechnical Specification 3.7.1.1setpoints withoutfurthermodifications tothestructure oftheTcchnical Specification. | |||
There-calculated setpoints arelikelytobelowerthanthosecurrently allowedbytheTechaical Specification. | |||
However,youshouldbeawareofatleasttwoconscrvatisms withtheequationYoumaywishtoreviewtheseconservatisms toevaluatetheuseoftheequationrelativetoyourplantspecificoperating objectives. | |||
Itispossibletorelaxsomeoftheseconservatisms foruseintheTechnical Specificatioa However,relaxation oftheconservatisms arelikelytoresultinmoresignificant changestothestructure oftheTechnical Spccificatioa First,theaboveequatioa(andtheexistingTechaical Specification 3.7.1.1)isconservative sinceitisbasedonthemaximumnumberofinoperable MSSVsperloop.Forexample,arepresentative fourloopplant,inaccordance withthecurrentTechnical Specification, shouldreduce'he neutronfluxsetpointto87%ifithasuptooneinoperable MSSVoneachloop.Thismeansthattheplantshouldusethissetpointwhetherthereareone,two,threeorfourinoperable MSSVs,aslongasthereisonlyoneinoperable MSSVpcrloop.Thus,theexistingTechnical Specification andtheaboveequationareconservative andbounding. | |||
However,anyrelaxation ofthisconservatism mustbeinterpreted withcare.Thereasonisthatthesteamgenerators mustbeprotcctcd 6'omanovcrpressurization condition duringalossofloadtransient. | |||
'I%ereareseveraleventsthatcouldleadtoalossofload,including theinadvertent closureofoneorallMSIVs.Theaffectedsteamgenerator musthaveasufficient numberofoperableMSSVstoprotectitfromanoverpressurizatioa condition, iftheMSIV(orMSIVs)wasiaadvertently closed.Anotherconservatism intheaboveequation(andtheexistingTechnical Specification 3.7.1.1)isinwwhichistheminimumtotalsteamQowratecapability oftheoperableMSSVsonanyonesteamgenerator. | |||
Thisvalueisconservative sinceitassumesthatifoneormoreMSSVsareinoperable perloop,theinoperable MSSVsarethelargestcapacityMSSVs,regardless ofwhetherthelargestcapacityMSSVsorthesmallercapacityMSSVsareinoperable. | |||
Theassumption hasbeenmadesothattheaboveequationisconsistent withthecurrentstructure ofTechnical Specification 3.7.1.1.(2)Asanalternative, plant-specific LOIJITanalysescouldbeperformed tomaximizetheallowable power.level foragivennumberofinoperable MSSVs.Depending onkeyspecificplantparameters, theseanalysesmaybeabletojustifythecoatinued validityofthecurrentTechnical Specificatioa (3)Considermodifying, asrequired, theBasesSectionforTechaical Specification 3/4.7.1.1 sothat.itisconsistent withtheplantsafetyanalysis. | |||
Thesafetyanalysiscriterion forpreventiag ovciprcssurization ofthesecondary sideisthattheprcssuredoesnotexceed110%ofthedesignpessureforanticipated transients. | |||
However,inreviewing severalplanttechaical specifications, a%418.wpf: | |||
tbsp11994 itwasnotedthatthebasesforsomeplantsstatethatthesafetyvalvesinsurethatthesecondary systempressurewillbelimitedtowithin10Soreven100%%uoofdesignprcssure. | |||
Thisisnotconsistent withthesafetyanalysisbasisandshouldberevisedtoindicate110%.@%418.vg)f:1b411994}} |
Revision as of 07:58, 29 June 2018
ML17332A999 | |
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Site: | Cook |
Issue date: | 10/20/1995 |
From: | INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG |
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Text
ATTACHMENT 2TOAEP'NRC'1213A EXISTINGTECHNICAL SPECIFICATION PAGESMARKEDTOREFLECTPROPOSEDCHANGES9510310312 951020PDRADOCK05000315PPDR 0
34.7SYSTEMS347.TGRBTNECYCLESAFETYVALVESNGCONDXTONFOROPERAON3.7.1.1Allmainsteamlinecodesafetyvalvesassociated witheachsteamgenerator shallbeOPERABLE.
ancC.v~lu~is>a~a.4With4reactorcoolantloopsandassociate steamgenerators in'perationpand withoneormoremainsteam1necodesafetyvalvesinop'arable, operation
,naproceedprovidethatwithin4hours,eithertheinoperable restoredtoOPlZstatus'rthePowerRangeNeutronFluxHighSetpointtripisreduced.perTable3.7-1;otherwise, beinae:-4e~HOTSTANDBYwithinthenext6hoursand.comply~~a@So%56cAAthA b.b.(Wi3reactorcoolantloopsandassociated steamgenerators inperation~
andwithoneormoremainsteamlinecodesafetyvalvesassociated withanoperating loopinoperable, operation 4MGMMnayproceedprovidedg thatnirhin4honte,eitherthein'operable
<~"+i~C~~s.restored toOPERABLEstatus~orthereactortripbreakersareopened;otherwise, bein~SHUTDOWNwithintheNext30hours.Hol-Theprovisions ofSpecification 3.0.4arenotapp1.$cable.SURVEXLLANCE REUIREMENTS 4.7.1.1.Eachmainsteamlinecodesafetyvalveshallbedemonstrated OPERABLE'naccordance withSpecification 4.0.5andwithliftsettingsasshowninTable4.7-1.Thesafetyvalveshallberesettothenominalvalue~1Xwheneverfoundoutsidethe+1Ktolerance.
qg~po,s-,~S ogSq~Q~Otee~i~Wk>M.3~COOKNUCLEARPLANT-UNlT13/47-1~HENTNO.k@0,464
'TABLE3.7-lHAXlHUHALLOWABLE POllERRAHGENEUTRONFLUXlllGIISETPOIHTMITllIHOPERAOLE STEAHEPIE~I'IKTEEEEPEPEIEWIE
~HaxinemtiumberofInoperable SafetyValvesonAnOeratinSteamGenerator HaximumAllowable PowerRangetleutronFluxilighSetpointPercentofRATEDTHERHALPOWER4I~~
/41VV<TheOPERABILITY ofthemainsteamlinecodesafetyvalvesensureschatthesecondary systempressurewillbelimitedcowt.thini.csdesignpressureof1085psigduringthemostsevereanticipated systemopera-tionalcransient.
Themaximumrelievt.ng capacityisassociated wichacurbinetripfrom100%RATEDTHER.fALPOMERcoincident withanassumedlossofcondenser heatsink(i.e.,nosceambypasscothecondenser).
Thespecified valveli.ftsettingsandrelieving capacities areinaccordance withtherequirements ofSectionIIIofcheASMEBoi.lerandPressureCode,1971Edition.Thetotalrelieving capacicyforallvalvesona11ofthe'steamli.nesis17,153,800 lbs/hrwhichisapproximately 121percentofthetocalsecondary steamflowof14,120,000 lbs/hrac100%RATEDTHERMALPOMER.Aminimumof2OPERABLEsafecyvalvesperoperabLesteamgenerator ensuresthatsufficient relievt.ng capacityi.savailable forcheallo~able THER.'iAL POWERrestri.ction inTable3.7-1.STARTUPand/orPOMEROPERATION inoperable withinthelimitations ofofchereduction insecondary systembythereducedreactortripseccingschannels.
Thereactortripsetpoincfollowing bases:isallowable withsafetyaalvestheACTIONrequiremencs onthebasissteamflowandTHLq.KLPOt:ERrequiredofthePowerRangeNeutronFluxreductions arederivedonthe.SPx(109)'XFor4loopoperaci.on Qplam..a.Harkr8%here:SPreducedreacctripsetpoinj.npercencofRATEDTHERMALPOPERVmaximumnumberofinablesafecyval.vespersceamline<<1,2or3.X-Totalreli.ev'ng capacityofalsafecyvalvespersteamline48,450lbs/hour.
YNaxumrelieving capacityofanyonesecyvalve57,690lbs/hour.
(10PowerRangeNeutronFlux-High TripSecpoincforloopoperaci.on.
D.C.COOK-UNIT1B3/47-1AHENDHENT NO.120 Relacementtextfor3/4.7.1.1 BasesHi<5=(100/Q)(4wpgZwhere:HiC=SafetyAnalysispowerrangehighneutronfluxsetpointinpercentQ=NominalNSSSpowerratingoftheplant(including reactorcoolantpumpheat)inMwtK=Conversion factor,947.82Q3tu/~Sec Mwtw,=Minimumtotalstcamflowratecapability oftheoperableMSSVsonanyonesteamgenerator atthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate, inlb/sec.Forexample,ifthemaximumnumberofinoperable MSSVsonanyonesteamgenerator isone,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating
- pressure, excluding thehighestcapacityMSSV.Ifthemaximumnumberofinoperable MSSVspersteamgenerator isthree,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating
- pressure, excluding thethreehighestcapacityMSSVs.h,,=Heatofvaporization forsteamatthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate inBtu/ibm4=NumberofloopsinplantThevaluescalculated fromthisalgorithm arethenadjustedlowerforuseinTechnical Specification 3.7.1.1toaccountforinstrument andchanneluncertainties by9%.Thisreducesthemaximumplantoperating powerlevelsothatitislowerthanthereactorprotection systemsetpointbyanappropriate operating margin.
34.7PLANTSYSTEMS34.7.1XNECYCLESFVALVESNGCONDONFOOPERAON3.7.1.1Allnsdnsteanlinecodesafetyvalvesssscclated vdeheachsteangenerator shallbeOPERABLE.
APPLXCABXLX Y:Modes1,2and3.~OTXON:moog'.CZ:
Valve@o~a.Wi.th4reactorcoolantloopsandassociate steamgenerators inoperation andwithoneormoremainsteam1necodesafetyvalvesinoperablL, operation maproceedprovidedg thatwithin4hours,eithertheinoperable restoredtoOPLEstatus>orthePowerRangeNeutronFluxHigh'ipetpoint'sreducedperTable3.7-1;otherwise, beinae-~~HOTSTANDBYwithinthenext6hoursand.Complot,40~clog~~4~ta4S.b.4Wi3reactorcoolantloopsandassociated steamgenerators in'perationyand withoneormoremainsteamlinecodesafetyvalvesassociated withanoperating loopinoperable, operation
~BOYImayproceedprovidedg thatwithin4hours,eitherthe'noperable V<QclS)oVC
~o-kerestoredtoOPERABLEstatus/or thereactortripbreakersareopened;otherwise, beinCGASHUTDOWNwithinthe'ext30hours.HoT'-Theprovisions'f Specification 3.0.4arenotapplicable.
SURVEXLLANCE REEMENTS4.7.1..1Eachmainsteamlinecodesafetyvalveshallbedemonstrated OPERABLEinaccordance withSpecification 4.0.5andwithliftsettingsasshowninTable4.7-1.Thesafetyvalveshallberesettothenominalvaluepl%whenever foundoutsidethe+1Ktolerance.
~P~g,sy~gQQ~>Q,~~9.0.9o~VO+aPP4cab4~f~iceieiODE3.COOKNUCLEARPLANT-UNIT.23/47-1AMENDMENT NO.Sa,167 TABLE3-1LLOWABLEOWNGEEURONGHSETPOINTWITINOPERABLE SESAFVALVESDURING4LOOPOPERA0MaximumNumberofInoperable SafetyValveso0eatnSteamGenerator MaximumAllowable PowerRangeNeutronFluxHighSetpointPercentoRATEDERMALPOWECOOKNUCLEARPLANT-UNIT23/CI.7-2 34.7PIANTSYSTEMSBASES34.7.1TURBINECYCLE34.7.1.1SAFETYVALVESTheOPERABILITY ofthemainsteamlinecodasafetyvalvesensureschacthesecondary systempressurevillbelimitedtovithin110iofi,tsdesignpressureof1085psigduringthemostsevereanticipated systemoperational czansient.
Th>>maximumreueving'capacity isassociated vithacuzbinetzipfrom100%RATEDTHERMALPOMERcoincident vithanassumedlossofcondensez heatsink(i.e.,nosteambypasstothecondenser).
Thespecified valveltfcsettingsandrelieving capacities areinaccordance vithcherequirements ofSectionIIIoftheASMEBoilerandPressureCode,1971Edition.Thetotalrelievtng capacityofallsafetyvalvesonallofthesteamlinesis17,153,800 lbs/hrvhichisatleast105percentofthemaximumsecondary steamflovrateat100%RATEDTHERMALPOVER.hminimumof2OPERABLEsafetyvalvespersteamgenerator ensuresthatsufficient relieving capacityisavailable forcheallovable THERMALPOVERrestriction inTable3.7-1.STARTUPand/orPOVKROPERATION isallovable vichsafetyvalvesinoperable vithinthelimitacions oftheACTIONrequirements onthebasisofthereduction insecondary syscemsteamflovandTHERMALPOMrequt.red bythereducedreactortripsettingsofthePoverRangeNeutronFluxchannels.
Thereactortripsetpotntreductions arederivedonthefolloving bases:For4loopoperation Where:SPreducedreactzipsecpointinperntofRATEDTHECALPOVER@pe~a.~hahVmaximumnumberofinope~safetyvalvespersteamlineXtotalrelievtncapacityofallstyvalvespezsteamlineinlbours4,2&8,450 Ymaxrelieving capacityofanyonesafealvelbs./hour 857,6909PoverRangeNeutronFlux-High TripSecpointfor4loopoperation COOKNUCLEARPLANT-UNIT2B3/47-1AMENDMENT NO.Sl.134 Relacementtextfor3/4.7.1.1 BasesHil=(100/Q)~(4)vh)Kwhere:Hi4=Safe@Analysis powerrangehighneutronfluxsetpointinpercentQ=NomaalNSSSpowerratingoftheplant(including reactorcoolantpumpheat)inMwtK=Contortion factor,947.82~Bto/SecMwtw,=Mimmxmtotalsteamflowratecapability oftheoperableMSSVsonanyonesteamgenerator atthehighestMSSI'opening pressureincluding tolerance andaccumulation, asappropriate, inIb/sec.Forexample,iftheaazimumnumberofinoperable MSSVsonanyonesteamgenerator isone,thenw,shouldbeasumnarion ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating
- pressure, exclaKagthehighestcapacityMSSV.Ifthemaximumnumberofinoperable MSSVspersteamgenerator isthm-thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMS'perating
- prcssure, excluding thethreehighestcapacityMSSVs.h<<=Heateiivaporization forsteamatthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappepriate inBtu/IbmI4=Numb'floopsinplantThevaluesahalatedfromthisalgorithm arethenadjustedlowerforuseinTechnical Specification 3.7.1.1toaccountforjumentandchanneluncertainties by9%.Thisrcduccsthcmaximumplantoperating powerlevelsothatitisloserthanthereactorprotection systemsetpointbyanappropriate operating margin.
ATTACHMENT 3TOAEP:NRC:1213A PROPOSEDREVISEDTECHNICAL SPECIFICATION PAGES 3/4LIMITINGCONDlTIONS FOROPERATION ANDSURVEILLANCE REQUIREMENTS 3/4.7PLANTSYSTEMS3/4.7.1TURBINECYCLESAFETYVALVESLIMITINGCONDITION FOROPERATION 3.7.1.1Allmainsteamlinecodesafetyvalvesassociated witheachsteamgenerator shallbeOPERABLE.
APPLICABILITY:
MODES1,2and3.ACTION:aoMODES1&2:With4reactorcoolantloopsandassociated steamgenerators inoperation, andwithoneormoremainsteamlinecodesafetyvalvesinoperable, operation mayproceedprovidedthatwithin4hours,eithertheinoperable valve(s)arerestoredtoOPERABLEstatus,orthePowerRangeNeutronFluxHighSetpointtripisreducedperTable3.7-1;otherwise, beinHOTSTANDBYwithinthenext6hoursandcomplywithactionstatement b.b.MODE3:Withaminimumof3reactorcoolantloopsandassociated steamgenerators inoperation, andwithoneormoremainsteamlinecodesafetyvalvesassociated withanoperating loopinoperable, operation mayproceedprovidedthatwithin4hours,eithertheinoperable valve(s}atbrestoredtoOPERABLEstatus,orthereactortripbreakersareopened;otherwise, beinHOTSHUTDOWNwithinthenext30hours.Theprovisions ofSpecification 3.0.4arenotapplicable.
SURVEILLANCE REUIREMENTS 4.7.1.1Eachmainsteamlinecodesafetyvalveshallbedemonstrated OPERABLEinaccordance withSpecification 4.0.5andwithliftsettingsasshowninTable4.7-1.Thesafetyvalveshallberesettothenominalvalue+1%wheneverfoundoutsidethe+1%tolerance.
4.7.1.2Theprovisions ofSpecification
4.0. 4arenotapplicable
forentryintoMODE3.COOKNUCLEARPLANT-UNIT 1Page3/47-1AMENDMENT 420,444,4' 3/4LIMITINGCONDITIONS FOROPERATION ANDSURVEILLANCE REQUIREMENTS 3/4.7PLANTSYSTEMSTABLE3.7-1MAXIMUMALLOWABLE POWERRANGENEUTRONFLUXHIGHSETPOINTWITHINOPERABLE STEAMLINESAFETYVALVESDURING4LOOPOPERATION MaximumNumberofInoperable SafetyValvesonAn0eratinSteamGenerator MaximumAllowable PowerRangeNeutronFluxHighSetpoint(PercentofRATEDTHERMALPOWER)65.146.528.0COOKNUCLEARPLANT-UNIT 1Page3/47-2 3/4.nBASES3/4.7PLANTSYSTE<MS3/4.7.1TURBINECYCLE3/4.7.1.1 SAFETYVALVESTheOPERABILITY ofthemainsteamlinecodesafetyvalvesensuresthatthesecondary systempressurewillbelimitedtowithin110%ofitsdesignpressureof1085psigduringthemostsevereanticipated systemoperational transient.
Themaximumrelieving capacityisassociated withaturbinetripfrom100%RATEDTHERMALPOWERcoincident withanassumedlossofcondenser heatsink(i.e.,nosteambypasstothecondenser).
Thespecified valveliftsettingsandrelieving capacities areinaccordance withtherequirements ofSectionIIIoftheASMEBoilerandPressureCode,1971Edition.ThesafetyvalveisOPERABLEwithaliftsettingofJ3%aboutthenominalvalue.However,thesafetyvalveshallberesettothenominalvalueJ1%wheneverfoundoutsidetheJ1%tolerance.
Thetotalrelieving capacityforallvalvesonallofthesteamlinesis17,153,800 lbs/hrwhichisapproximately 121percentofthetotalsecondary steamflowof14,120,000 Ibs/hrat100%RATEDTHERMALPOWER.Aminimumof2OPERABLEsafetyvalvesperoperablesteamgenerator ensuresthatsufficient relieving capacityisavailable fortheallowable THERMALPOWERrestriction inTable3.7-1.STARTUPand/orPOWEROPERATION isallowable withsafetyvalvesinoperable withinthelimitations oftheACTIONrequirements onthebasisofthereduction insecondary systemsteamflowandTHERMALPOWERrequiredbythereducedreactortripsettingsofthePowerRangeNeutronFluxchannels.
Thereactortripsetpointreductions arederivedonthefollowing bases:ffso=iannfffi~r(4w&Kwhere:Hi4=SafetyAnalysispowerrangehighneutronfluxsetpointinpercentQ=K=hfNominalNSSSpowerratingoftheplant(including reactorcoolantpumpheat)inMwtConversion factor,947.82~Btu/SecMwtMinimumtotalsteamflowratecapability oftheoperableMSSVsonanyonesteamgenerator atthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate, inlb/sec.Forexample,ifthemaximumnumberofinoperable MSSVsonanyonesteamgenerator isone,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating
- pressure, excluding thehighestcapacityMSSV.Ifthemaximumnumberofinoperable MSSVspersteamgenerator isthree,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating
- pressure, excluding thethreehighestcapacityMSSVs.Heatofvaporization forsteamatthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate inBtu/ibm4=NumberofloopsinplantThevaluescalculated fromthisalgorithm arethenadjustedlowerforuseinTechnical Specification 3.7.1.1toaccountforinstrument andchanneluncertainties by9%.Thisreducesthemaximumplantoperating powerlevelsothatitislowerthanthereactorprotection systemsetpointbyanappropriate operating margin.COOKNUCLEARPLANT-UNIT 1PageB3/47-1AMENDMENT 420
3/4'IMITINGCONDITIONS FOROPERATION ANDSURVEILLANCE REQUIREMENTS 3/4.7PLANTSYSTEMS3/4.7.1TURBINECYCLESAFETYVALVESLIMITINGCONDITION FOROPERATION 3.7.1.1Allmainsteamlinecodesafetyvalvesassociated witheachsteamgenerator shallbeOPERABLE.
APPLICABILITY:
MODES1,2and3.ACTION:MODES1&2:With4reactorcoolantloopsandassociated steamgenerators inoperation, andwithoneormoremainsteamlinecodesafetyvalvesinoperable, operation mayproceedprovidedthatwithin4hours,eithertheinoperable valve(s)arerestoredtoOPERABLEstatus,orthePowerRangeNeutronFluxHighSetpointtripisreducedperTable3.7-1;otherwise, beinHOTSTANDBYwithinthenext6hoursandcomplywithactionstatement b.b.MODE3:Withaminimumof3reactorcoolantloopsandassociated steamgenerators inoperation, andwithoneormoremainsteamlinecodesafetyvalvesassociated withanoperating loopinoperable, operation mayproceedprovidedthatwithin4hours,eithertheinoperable valve(s)arerestoredtoOPERABLEstatus,orthereactortripbreakersareopened;otherwise, beinHOTSHUTDOWNwithinthenext30hours.c.Theprovisions ofSpecification 3.0.4arenotapplicable.
SURVEILLANCE REUIREMENTS 4.7.1.1Eachmainsteamlinecodesafetyvalveshallbedemonstrated OPERABLEinaccordance withSpecification 4.0.5andwithliftsettingsasshowninTable4.7-1.Thesafetyvalveshallberesettothenominalvalue+1%wheneverfoundoutsidethe+1%tolerance.
4.7.1,2Theprovisions ofSpecification
4.0. 4arenotapplicable
forentryintoMODE3.COOKNUCLEARPLANT-UNIT 2Page3/47-1 3/4LIMITINGCONDITIONS FOROPERATION ANDSURVEILLANCE REQUIREMENTS 3/4.7PLANTSYSTEMSTABLE3.7-1MAXIMUMALLOWABLE POWERRANGENEUTRONFLUXHIGHSETPOINTWITHINOPERABLE STEAMLINESAFETYVALVESDURING4LOOPOPERATION MaximumNumberofInoperable SafetyValvesonAnyOperating SteamGenerator MaximumAllowable PowerRangeNeutronFluxHighSetpoint(PercentofRATEDTHERMALPOWER)61.643.926.2COOKNUCLEARPLANT-UNIT 2Page3/47-2AMENDMENT 3/4'ASES3/4.7PLANTSYSTEMS3/4.7.1TURBINECYCLE3/4.7.1.1 SAFETYVALVESTheOPERABILITY ofthemainsteainlinecodesafetyvalvesensuresthatthesecondary systempressurewill'belimitedtowithin110%ofitsdesignpressureof1085psigduringthemostsevereanticipated systemoperational transient.
Themaximumrelieving capacityisassociated withaturbinetripfrom100%RATEDTHERMALPOWERcoincident withanassumedlossofcondenser heatsink(i.e.,nosteambypasstothecondenser).
Thespecified valveliftsettingsandrelieving capacities areinaccordance withtherequirements ofSectionIIIoftheASMEBoilerandPressureCode,1971Edition.ThesafetyvalveisOPERABLEwithaliftsettingof+3%aboutthenominalvalue.However,thesafetyvalveshallberesettothenominalvalueJ1%wheneverfoundoutsidethe+1%tolerance.
Thetotalrelieving capacityofallsafetyvalvesonallofthesteamlinesis17,153,800 lbs/hrwhichisatleast105percentofthemaximumsecondary steamflowrateat100%RATEDTHERMALPOWER.Aminimumof2OPERABLEsafetyvalvespersteamgenerator ensuresthatsufficient relieving capacityisavailable fortheallowable THERMALPOWERrestriction inTable3.7-1.STARTUPand/orPOWEROPERATION isallowable withsafetyvalvesinoperable withinthelimitations oftheACTIONrequirements onthebasisofthereduction insecondary systemsteamflowandTHERMALPOWERrequiredbythereducedreactortripsettingsofthePowerRangeNeutronFluxchannels.
Thereactortripsetpointreductions arederivedonthefollowing bases:ffsto=taooft2t
~r(4w&z)Kwhere:Hi4=SafetyAnalysispowerrangehighneutronfluxsetpointinpercentQ=NominalNSSSpowerratingoftheplant(including reactorcoolantpumpheat)inMwtK=Conversion factor,947.82~Bto/SecMwtw,=Minimumtotalsteamflowratecapability oftheoperableMSSVsonanyonesteamgenerator atthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate, inlb/sec.Forexample,ifthemaximumnumberofinoperable MSSVsonanyonesteamgenerator isone,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating
- pressure, excluding thehighestcapacityMSSV.Ifthemaximumnumberofinoperable MSSVspersteamgenerator isthree,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating
- pressure, excluding thethreehighestcapacityMSSVs.h<<=Heatofvaporization forsteamatthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate inBtu/ibm4=NumberofloopsinplantThevaluescalculated fromthisalgorithm arethenadjustedlowerforuseinTechnical Specification 3.7.1.1toaccountforinstrument andchanneluncertainties by9%.Thisreducesthemaximumplantoperating powerlevelsothatitislowerthanthereactorprotection systemsetpointbyanappropriate operating margin.COOKNUCLEARPLANT-UNIT 2PageB3/47-1AMENDMENT 82,434 0I ATTACHMENT 4TOAEP:NRC:1213A WESTINGHOUSE NSAL94-001"OPERATION ATREDUCEDPOWERLEVELSWITHINOPERABLE MSSV'S" I
Westinghouse EnergySystemsBusinessUnitNUCLEARSAF1TYADVISORYLETTER'HISISANOTIHCATION OFARECENTLYIDENTIFIED POTENTIAL SAFETYISSUEPERTAINING TOBASICCOMPONENTS'UPPLIED BYWESTINGHOUSE.
THISINFORMATION ISBEINGPROVIDEDTOYOUSOTHATAREVIEWOFTHISISSUECANBECONDUCEDBYYOUTODETERMINE IFANYACTIONISREQUIRED.
P.O.Box355,Pittsburgh, PA152304355
Subject:
Operation atReducedPowerLevelswithInoperable MSSVsNumbet:NSAL-944)01 BasicComponent:
LossofLoadfi'urbinc TripAnalysisforPlantLicensing BasisDatesOII20$4Plants:SecEnclosedListSubstantial SafetyHazardorFailuretoComplyPursuantto10CFR21.21(a)TransferofInformation Pursuantto10CFR21.21(b)AdvisoryInformation Pursuantto10CFR21.21(c)(2)
SUMMARYYesCiNotlYcs0Ycs0Westinghouse hasidentified apotential safetyissueregarding plantoperation withinTechnical Specification Table3.7-1.Thisissuedoesnotrepresent asubstantial safetyhazardforyourplantpursuantto10CFR21.However,thisissuedoesrepresent acondition whichmayimpactyourplant'slicensing basis.ITable3.7-1allowsplantstooperatewithareducednumberofoperableMSSVsatareducedpowerlevel,asdetermined bythehighneutronQuxtripsetpoint.
ThcFSARlossofload/turbine trip(LOIJIT)analysisfromfullpowerboundsthecasewhereailMSSVsareoperable.
TheFSAR(LOLfIT)eventmaynotbeboundingfortheallowable operating configurations ofTable3.7-1sincethehighneutronfiuxtripsetpojnt, whichisidentified inTable3.7-1foracorresponding numberofinoperable MSSVs,maynotbelowenoughtoprecludeasecondary sideoverpressurization condition.
Asaresult,thebasisforTable3.7-1maynotbesuQicient toprecludeoveipressurization ofthesecondaty sideofthesteamgenerator.
'Therefore, itisrecommended thatyoureviewtheenclosedinformation todeterinine thcapplicability ofthisissuetoyourplant.Theenclosedinfortnation containsamoredetaileddescription oftheissueandidentifies solutions thatyoumaywishtopursuetoaddressthisissue.Thesesolutions include,butarenotlimitedto,areevaluation oftheLOIJITanalysisand/orachangeto~Technical Specification Table3.7-1.Additional information, ifrequired, maybeobtainedfromthcoriginator.
Tclephonc 412-3746460.
Originator.
.W.FasnachtStrategic Licensing IssuesH.A.Scpp,Manager,Strategic Licensing Issuesa%418.wpf:
1b412094
PlantsAffectedD.C.Cook1&2J.M.FarleyI&2Byron1&2Braidwood I&2V.C.SummerIZion1&2ShearonHarrisIW.B.McGuireI&2CatawbaI&2BeaverValleyI&2TurkeyPoint3&4VogtleI&2IndianPoint2&3SeabrookIMillstone 3DiabloCanyonI&2WolfCreekCallawayIComanchePeakI&2SouthTexasI&2SequoyahI&2NorthAnnaI&2WattsBarI&2Size,well BKori1,2,3
&4Yonggwang I&2SalemI&2@%418.wpf:1b411994 II 04 IssueDescritionWestinghouse hasidentified adeficiency inthebasisforTechnical Specification 3.7.1.1.ThisTechnical Specification allowstheplanttooperateatareducedpowerlevelwithareducednumberofoperableMainSteamSafetyValves(MSSVs).Thedeficiency isintheassumption thatthemaximumallowable initialpowerlevelisalinearfunctionoftheavailable MSSVreliefcapacity.
Thelinearfunctionisidentified intheBasesSectionforTechnical Specification 3/4.7.1.1 andisprovidedasfollows:Sp=(X)aO(V)x(i(e)XSP=Reducedreactortripsetpointin%ofRATEDTHERMALPOWERV=Maximumnumberofinoperable safetyvalvespersteamlineX=Totalrelieving capacityofallsafetyvalvespersteamlineinibm/hour(109)=Maximumrelieving capacityofanyonesafetyvalveinIbm/hourPowerrangeneutronflux-high tripsetpointforallloopsinoperation Undercerfainconditions andwithtypicalsafetyanalysisassumptions, aLossofLoad/Drrbine Triptransient frompart-power conditions mayresultinoverpressurization ofthemainsteamsystemwhenoperWnginaccordance withthisTechnical Specification.
'Ihefollowing discussion describes theissueinmoredetailandprovidesrecommended alternatives foraddressing theissue.Technical Evaluation
'IheLossofLoad/Turbine Trip(LOLGT)eventisanalyzedintheFSARtoshowthatcorepro~onmarginsaremaintained (DNBR),theRCSwillnotoverpressurize, andthemainsteamsystemwillnotoveipressurize.
Theanalysisassumesanimmediate lossofsteamrelieving capability throughtheturbineandcoincident lossofallmainfeedwater.
Nocreditistakenforthedirectreactortriponturbinetrip,sincethistripwouldnotbeactuatedforthecaseofalossofsteamload.Rather,thetransient isterminated byareactortriponhighpressurizer
- pressure, overtemperature AT,orlowsteamgenerator waterlevel.Secondary sideov'erpressure protection isprovidedbyactuation oftheMainSteamSafetyValves(MSSVs),whicharedesignedtorelieveatleastfullpowernominalsteamflow.'IlieanalysisverifiesthattheMSSVcapacityissufficient topreventsecondary sidepressurefimm.exceeding 110percentofthedesignpressure.
0%418.vq>f:tb411994
TheFSARonlyanalyzestheLOIJITtransient GomtheMpowerinitialcondition, withcasesexamining theeffectsofassumingprimarysidepressurecontrolanddifferent reactivity feedbackconditions.
Withfullyoperational MSSVs,itcanbedemonstrated thatoverpressure protection isprovidedforallinitialpowerlevels.However,formostplants,Technical Specification 3.7.1.1allowsoperation withareducednumberofoperableMSSVsatareducedpowerlevelasdetermined byresetting thepowerrangehighneutronfiuxsetpoint.
ThisTechnical Specification isnotbasedonadetailedanalysis, butratherontheassumption thatthemaximumallowable initialpowerlevelisalinearfunctionoftheavailable MSSVreliefcapacity.
- Recently, ithasbeendetermined thatthisassumption isnotvalid.'Iheproblemisthatifmainfeedwater islost,areactortripisnecessary topreventsecondary sideoverpressurization forallpostulated coreconditions.
Athighinitialpowerlevelsareactortripisactuatedearlyinthetransient as.aresultofeitherhighpressurizer pressureorovertemperature hT.Thereactortripterminates thetransient andtheMSSVsmaintainsteampressurebelow110%ofthedesignvalue.Atlowerinitialpowerlevelsareactortripmaynotbeactuatedearlyinthetransient.
Anovertempeiature hTtripisn'tgenerated sincethecorethermalmarginsareincreased atlowerpowerlevels.Ahighpressurizer pressuretripisn'tgenerated iftheprimarypressurecontrolsystemsfunctionnormally.
Thisresultsinalongertimeduringwhichprimaryheatistransferred tothesecondary side.'Ihereactoreventually, tripsonlowsteamgenerator waterlevel,butthismaynotoccurbeforesteampressureexceeds110%ofthedesignvalueifoneormoreMSSVsareinoperable inaccordance withtheTechnical Specification.
Duetothewidevarietyofplantdesignfeaturesthatareimportant totheLOIJITanalysis, itisdifficult toperformagenericevaluation toshowthattheissuedoesnotapplytocertainplants.Thefollowing keyparameters haveasignificant effectonthesecondary sidepressuretransient MSSVreliefcapacityModerator Temperature Coefficient (MTC)MarginbetweentheMSSVsetpressures (including tolerance) andtheoverpressure limitLow-lowsteamgenerator waterlevelreactortripsetpointSafetSinificance TheTechnical Specifications formostplantsallowoperation atareducedpowerlevelwithinoperable MSSVs.Fromalicensing basisperspective, thiscondition mayresultinsecondary sideoverpressurization intheeventofaLOIJITtransient.
Thelicensing basisforanticipated operational occurrences (ANSCondition IIevents)typically requiresthatthesecondary sideprcssureremainbelow110%ofthedesignvalue.a%418.wpf:
Ib411994 Westinghouse hasdetermined thatthisissuedoesnotrepresent asubstantial safetyhazard.Thereareseveralmitigating factorswhichprovideassurance thatthereisnolossofsafetyfunctiontotheexteatthatthereisamajorreduction inthedegreeofprotection providedtothepublichealthandsafety.Theseinclude,butarenotlimitedto,thefollowing:
1.Adequateoverpressure protection isprovidedatallpowerlevelsifalloftheMSSVsareoperable.
2.Ifareactortripdoesnotoccurbutmainfeedwater fiowismaintained, operation inaccordance withtheTechnical Specification Table3.7-1willnotresultinanoverpressure condition.
3.InanyLOIJITtransient, theatmospheric steamdumpvalvesand/orcondenser steamdumpvalvesactuatetorelieveenergyiromthesteamgenerators priortotheopeningoftheMSSVs,andcontinuetorelievesteamiftheMSSVsdoopen.Sinceitisnotasafety-grade
- function, steamdumpisnotassumedtooperateinthesafetyanalysis; however,inrealityitisthefirstlineofdefenseinprotecting thesecondary systemagainstoverpressurizatioa.
Itisveryimprobable thatallthesecompoaents wouldbeinoperable coincident withinoperable MSSVs.4.Evennearthebeginning ofcorelifewithapositiveorzeroMTC,theprimaryvolantheatupresulting fromthetransient wouldtendtodrivethehGCnegative, whichwould.reducethecorepoweraadheatinputtothecoolaat.Thiswouldresultin'alowerrequiredMSSVcapacitytopreventsecondary ovegressurization.
Thesafetyanalysisdoesnotcreditthereduction ofMTCduringthetransient.
NRCAwareness IReortabilit Westinghouse hasnotnotifiedtheNRCofthisissue,baseduponthedetermination thatitdoesaotrepresent asubstantial safetyhazardpursuantto10CFR21.However,Westinghouse willsendacopyofthislettertotheNRCsincethisissueimpactsinformation contained inNUREG-1431, "Standard Technical Specifications, Westinghouse Plants".Recommendations Toaddressthisissue,thefollowing actionsmaybeconsidered:
(1)ModifyTechaical Specificatioa 3.7.1.1(orequivalent) andtheassociated basissuchthatthemaximumpowerlevelallowedforoperation withinoperable MSSVsisbelowtheheatremovingcapability oftheoperableMSSVs.Aconservative waytodothisistosetthepowerrangehighaeutmnfiuxsetpointtothispowerlevel,thusensuringthattheactualpowerlevelcannotexceed@%418.wpf:1b411994
~~thisvalue.Tocalculate thissetpoint, thegoverning equationistherelationship q=mhh,whereqistheheatinputfmmtheprimaryside,misthesteamflowrateandhhistheheatofvaporization atthesteamreliefpressure(assuming nosubcooled fecdwater).
Thus,analgorithm foruscindefiningtherevisedTechnical Specification tablesetpointvalueswouldbe:Hig=(100/Q)~(wPN)Kwhere:'ig=SafetyAnalysispowerrangehighneutronfluxsetpoint, percentQ=NominalNSSSpowerratingoftheplant(including reactorcoolantpumpheat),MwtK=Conversion factor,947.82MwtwsMinimumtotalsteamlowratecapability oftheoperableMSSVsonanyonesteamgenerator atthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate, inib/sec.Forexample,ifthemaximumnumberofinoperable MSSVsonanyonesteamgenerator isone,thenw,shouldbeasummation ofthecapacityoftheoperableMSSVsatthehighestoperableMSSVoperating
- prcssure, excluding thehighestcapacityMSSV.Ifthemaximumnumberofinoperable MSSVsperstcamgenerator isthreethenw,shouldbeasummation ofthecapacityofthcoperableMSSVsatthehighestoperableMSSVoperating
- prcssure, excluding thethreehighestcapacityMSSVs.h+=heatofvaporization forstcamatthehighestMSSVopeningpressureincluding tolerance andaccumulation, asappropriate, Btu/1bmN=Numberofloopsin plantThevaluescalculated fromthisalgorithm mustthenbeadjustedlowerforuscinTechnical Specification 3.7.1.1toaccountforinstrument andchanneluncertainties (typically 9%power).Themaximumplantoperating powerlevelwouldthenbelowerthanthereactorprotection systemsetpointbyanappropriate operating margin.0%418.wpf:
1b411994 kk
~y~0C~c.Itshouldbenotedthattheuscofthisequatioawillresolvetheissueideatified inthisletterbyeaablingyoutore~culate yourTechnical Specification 3.7.1.1setpoints withoutfurthermodifications tothestructure oftheTcchnical Specification.
There-calculated setpoints arelikelytobelowerthanthosecurrently allowedbytheTechaical Specification.
However,youshouldbeawareofatleasttwoconscrvatisms withtheequationYoumaywishtoreviewtheseconservatisms toevaluatetheuseoftheequationrelativetoyourplantspecificoperating objectives.
Itispossibletorelaxsomeoftheseconservatisms foruseintheTechnical Specificatioa However,relaxation oftheconservatisms arelikelytoresultinmoresignificant changestothestructure oftheTechnical Spccificatioa First,theaboveequatioa(andtheexistingTechaical Specification 3.7.1.1)isconservative sinceitisbasedonthemaximumnumberofinoperable MSSVsperloop.Forexample,arepresentative fourloopplant,inaccordance withthecurrentTechnical Specification, shouldreduce'he neutronfluxsetpointto87%ifithasuptooneinoperable MSSVoneachloop.Thismeansthattheplantshouldusethissetpointwhetherthereareone,two,threeorfourinoperable MSSVs,aslongasthereisonlyoneinoperable MSSVpcrloop.Thus,theexistingTechnical Specification andtheaboveequationareconservative andbounding.
However,anyrelaxation ofthisconservatism mustbeinterpreted withcare.Thereasonisthatthesteamgenerators mustbeprotcctcd 6'omanovcrpressurization condition duringalossofloadtransient.
'I%ereareseveraleventsthatcouldleadtoalossofload,including theinadvertent closureofoneorallMSIVs.Theaffectedsteamgenerator musthaveasufficient numberofoperableMSSVstoprotectitfromanoverpressurizatioa condition, iftheMSIV(orMSIVs)wasiaadvertently closed.Anotherconservatism intheaboveequation(andtheexistingTechnical Specification 3.7.1.1)isinwwhichistheminimumtotalsteamQowratecapability oftheoperableMSSVsonanyonesteamgenerator.
Thisvalueisconservative sinceitassumesthatifoneormoreMSSVsareinoperable perloop,theinoperable MSSVsarethelargestcapacityMSSVs,regardless ofwhetherthelargestcapacityMSSVsorthesmallercapacityMSSVsareinoperable.
Theassumption hasbeenmadesothattheaboveequationisconsistent withthecurrentstructure ofTechnical Specification 3.7.1.1.(2)Asanalternative, plant-specific LOIJITanalysescouldbeperformed tomaximizetheallowable power.level foragivennumberofinoperable MSSVs.Depending onkeyspecificplantparameters, theseanalysesmaybeabletojustifythecoatinued validityofthecurrentTechnical Specificatioa (3)Considermodifying, asrequired, theBasesSectionforTechaical Specification 3/4.7.1.1 sothat.itisconsistent withtheplantsafetyanalysis.
Thesafetyanalysiscriterion forpreventiag ovciprcssurization ofthesecondary sideisthattheprcssuredoesnotexceed110%ofthedesignpessureforanticipated transients.
However,inreviewing severalplanttechaical specifications, a%418.wpf:
tbsp11994 itwasnotedthatthebasesforsomeplantsstatethatthesafetyvalvesinsurethatthesecondary systempressurewillbelimitedtowithin10Soreven100%%uoofdesignprcssure.
Thisisnotconsistent withthesafetyanalysisbasisandshouldberevisedtoindicate110%.@%418.vg)f:1b411994