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{{#Wiki_filter:EMERGENCYCORECOOLINGSYSTEMSSURVEILLANCEREUIREMENTSContinued2.Atleastonceper18months.BoronInjectionThrottleValvesValveNumberl.2-SI-141Ll2.2-SI-141L23.2-SI-141L34.2-SI-141L4SafetyInjectionThrottleValvesValveNumber1.2-SI-121N2.2-SI-121'Sh.ByperformingaflowbalancetestduringshutdownfollowingcompletionofmodificationstotheECCSsubsystemthatalterthesubsystemflowcharacteristicsandverifyingthefollowingflowrates:BoronInjectionSystemSinlePuLoop1BoronInjectionFlow117.5gpmLoop2BoronInjectionFlow117.5gpmLoop3BoronInjectionFlow117.5gpmLoop4BoronInjectionFlow117.5gpmSafetyInjectionSystemSinlePumo""Loop1and4ColdLeg.Flow>300@pmLoop2and3ColdLegFlow>300gpm**CombinedLoop1,2,3and4ColdLegFlow(singlepump)<640gpm.TotalSIS(singlepump)flow,includingminiflow,shallnotexceed700gpm.AmendmentNo."TheflowrateineachBoronInjection(BI)lineshouldbeadjustedtoprovide117.5gpm(nominal)flowintoeachloop.Undertheseconditionsthereiszeromini-flowand80gpmsimulatedRCPsealinjectionlineflow.TheactualflowineachBIlinemaydeviatefromthenominalsolongasthedifferencebetweenthehighestandlowestflowis10gpmorlessandthetotalflowtothefourbranchlinesdoesnotexceed470gpm.Minimumflow(totalflow)requiredis345.8gpmtothethreemostconservative(lowest&low)branchlines.84032002i48403l5PDRADOCK05000316PPDR0.C.COOK-UNIT23/45-6 SPECIALTESTEXCEPTIONPOSITIONXNDXCATORCHANNELSSKJTDONNLIMITINGCONDITIONFOROPERATION3.10.5ThelimitationsofSpecification3.1.3.3maybesuspendedduzingtheperformanceofindividualfulllength(shutdownandcontrol)roddroptimemeasuzementsprovided;a.Onlyoneshutdownorcontrolbankiswithdrawnfromthefullyinsertedpositionatatime,andb.ThegroupdemandpositionindicatorisOPERABLEduringthewithdrawaloftherods.APPLICABILITY:MODES3,4and5duringperformanceofroddroptlmemeasurements.ACTION>liththegroupdemandpositionindicatorinoperable,ormorethanonebankofrodswithdrawn,immediatelyopenthereactortripbreakers.SURVEILLANCEREQUIREMENTS4.10.5Eachoftheaboverequiredgroupdemandpositionindicator(s)shallbedetexminedtobeOPERABLEbymovementoftheassociatedshutdownorcontrolrodsatleast8stepsinanyonedirectionwithin24hourspriortothestartoftherod,droptimemeasurements.D.C.COOK-UNIT23/410-5 Mr.HaroldR.Dent-10-AEP:NRC:0860A~~ATTACHMENT4TOAEP:NRC:0860AWESTINGHOUSESUMMARYOFTHESAFETYEVALUATIONFORINCREASEDSZPUMPMINIFLOW LOCAEVALUATIONFORD.C.COOKUNIT2WITHREDUCEDHIGHHEADSAFFTYINJECTIONThisevaluationassessestheimpactofreducedhighheadsafetyinjectiononECCSperformanceinresponsetoaLOCAforthe0.CCookUnit2plant.WSafeguardsSystemsperformedanindependentcalcula-tionevaluatingtheimpacttohighheadsafetyinjection{HHSI)ofincmasingHHSIpumpminiflowfrom30gpmto60gpm.Thecalculationassumeda60gpmminiflowandthateachpairofcoldlegsreceivesgreaterthan300gpmduringflowbalancetesting.TheECCSflowrateswerethencalculatedusingthevendorperformancecurvedegradedby5%ofdesignhead.ThetotaldeliveredsafetyinjectionflowratestotheRCSforboth30gpmand60gpmareshowninTableI.Thereductionoft'otal'afetyinjectionis-3-5Xintherangeof1200-600psiaimportantfor'-this'valuation.LareBreakLOCAImactHHSIpumpflowprovidesaninsignificantproportionofthetotal6IflowduringalargebreakaccidentwhereRCSpressurerapidlydropstonearatmospheric.Accumulatorandlowheadsafetyinjection(RHR)flowareimportantforthispostulatedaccident.Forthisreason,smallchangesinHHSIpumpflowhaveanegligibleeffectonthelargeLOCAcalculatedpeakcladtemperature.SmallBreakLOCAImactTheeffectofHHSI'reductiononsmallbreakLOCAisdetermined.viaananalysiswiththeapprovedWsmallbreakLOCAevaluationmodelnerformedonthe0.C.CookUnit1plant,whichwasanalyzedat3411MWtcorepower.ThecalculatedPCTincreasederivedfromthisLOCAanalysisis86.1'F,calculatedontheworstbreaksize.TheinclusionofthisPCTincreaseeffecttothebasePCTof1668'F(worstbreaksize)for0.C.CookUnit2yieldsavaluewellbelowthe10CFR50.46limitof2200'FandislesslimitingthanthecurrentworstlargebreakPCT.Thesensit'ivityofPCTduetosmallHHSIflowreductionsdevelopedwithD.C.CookUnit1isapplicableandboundingfor0.C.CookUnit2forthefollowingreasons:
{{#Wiki_filter:EMERGENCY CORECOOLINGSYSTEMSSURVEILLANCE REUIREMENTS Continued 2.Atleastonceper18months.BoronInjection ThrottleValvesValveNumberl.2-SI-141Ll2.2-SI-141L23.2-SI-141L34.2-SI-141L4SafetyInjection ThrottleValvesValveNumber1.2-SI-121N2.2-SI-121'Sh.Byperforming aflowbalancetestduringshutdownfollowing completion ofmodifications totheECCSsubsystem thatalterthesubsystem flowcharacteristics andverifying thefollowing flowrates:BoronInjection SystemSinlePuLoop1BoronInjection Flow117.5gpmLoop2BoronInjection Flow117.5gpmLoop3BoronInjection Flow117.5gpmLoop4BoronInjection Flow117.5gpmSafetyInjection SystemSinlePumo""Loop1and4ColdLeg.Flow>300@pmLoop2and3ColdLegFlow>300gpm**Combined Loop1,2,3and4ColdLegFlow(singlepump)<640gpm.TotalSIS(singlepump)flow,including miniflow,shallnotexceed700gpm.Amendment No."TheflowrateineachBoronInjection (BI)lineshouldbeadjustedtoprovide117.5gpm(nominal) flowintoeachloop.Undertheseconditions thereiszeromini-flow and80gpmsimulated RCPsealinjection lineflow.TheactualflowineachBIlinemaydeviatefromthenominalsolongasthedifference betweenthehighestandlowestflowis10gpmorlessandthetotalflowtothefourbranchlinesdoesnotexceed470gpm.Minimumflow(totalflow)requiredis345.8gpmtothethreemostconservative (lowest&low) branchlines.84032002i4 8403l5PDRADOCK05000316PPDR0.C.COOK-UNIT23/45-6 SPECIALTESTEXCEPTION POSITIONXNDXCATOR CHANNELSSKJTDONNLIMITINGCONDITION FOROPERATION 3.10.5Thelimitations ofSpecification 3.1.3.3maybesuspended duzingtheperformance ofindividual fulllength(shutdown andcontrol)roddroptimemeasuzements provided; a.Onlyoneshutdownorcontrolbankiswithdrawn fromthefullyinsertedpositionatatime,andb.Thegroupdemandpositionindicator isOPERABLEduringthewithdrawal oftherods.APPLICABILITY:
1.Thetwoplants'ydrauliccharacteristicsarenearlyidentical.TheonlysignificantdifferenceisUnit1has15x15fuelandUnit2has17x17fuel.Hutmoreimportantlythedifferenceinfuelassemblyf1owareasbetweenthetwodesignsislesstha'n0.3%.2.TheeffectofreducedHHSIonthetransientishydrau-.lic.ReductioninSIdiminishestheeffectsofbofloffreplenishingfnthecore.Thus,smallreductionindowncomerlevelandcoremixtureheightwillresult.Thiseffectiswellbehavedandobservedthrough.smallLOCAanalysesperformedfornumerousplantsstudyingSleffects.3.Theeffectofareductionincoremixtureheightin-creasesthelengthofcoreuncoveredandthustheenthalpyriseofthesteam.Thesteamenthalpyattheuncoveredelevationsdeterminescladtemperaturesincethetransientisquasi-steadystateduringthecladheatupperiod.4.ThesmallLOCAanalysisforUnit1wasperformedat3411MMt,similartotheCookUnit2power.There-fore,theadditionalenthalpyrisewillbecalculatedcorrectly.5.TheheatlineargenerationrateForUnit1isgreaterthanUnit2duetofewerfuelrods.Therefore,theeffectonPCTofreducedHHSIwillbemaximized.6.Otherconservatismsintheanalysisexist.Forexample,thesmallLOCAanalysisforUnit2assumedanFgof2.32whiletheplantislimitedinoperationto2.04bylargebreakconsiderations.
MODES3,4and5duringperformance ofroddroptlmemeasurements.
ThisevaluationhasassessedtheimpactofreducedHHSIontheperformanceoftheECCSattheD.C.CookUnit2plant.ThereducedHHSIhasamaximumimpactof86.1'FonpeakcladtemperatureforasmallLOCA.TheinclusionofthisPCTincreasetothebasesmallLOCAPCTof1668'FforD.C.CookUnit2yieldsavaluewellbelowthe10CFR50.46limitof2200'FandislesslimitingthanthecurrentworstlargebreakPCT.  
ACTION>liththegroupdemandpositionindicator inoperable, ormorethanonebankofrodswithdrawn, immediately openthereactortripbreakers.
SURVEILLANCE REQUIREMENTS 4.10.5Eachoftheaboverequiredgroupdemandpositionindicator(s) shallbedetexmined tobeOPERABLEbymovementoftheassociated shutdownorcontrolrodsatleast8stepsinanyonedirection within24hourspriortothestartoftherod,droptimemeasurements.
D.C.COOK-UNIT23/410-5 Mr.HaroldR.Dent-10-AEP:NRC:0860A~~ATTACHMENT 4TOAEP:NRC:0860A WESTINGHOUSE SUMMARYOFTHESAFETYEVALUATION FORINCREASED SZPUMPMINIFLOW LOCAEVALUATION FORD.C.COOKUNIT2WITHREDUCEDHIGHHEADSAFFTYINJECTION Thisevaluation assessestheimpactofreducedhighheadsafetyinjection onECCSperformance inresponsetoaLOCAforthe0.CCookUnit2plant.WSafeguards Systemsperformed anindependent calcula-tionevaluating theimpacttohighheadsafetyinjection
{HHSI)ofincmasing HHSIpumpminiflowfrom30gpmto60gpm.Thecalculation assumeda60gpmminiflowandthateachpairofcoldlegsreceivesgreaterthan300gpmduringflowbalancetesting.TheECCSflowrates werethencalculated usingthevendorperformance curvedegradedby5%ofdesignhead.Thetotaldelivered safetyinjection flowrates totheRCSforboth30gpmand60gpmareshowninTableI.Thereduction oft'otal'afetyinjection is-3-5Xintherangeof1200-600psiaimportant for'-this'valuation.
LareBreakLOCAImactHHSIpumpflowprovidesaninsignificant proportion ofthetotal6IflowduringalargebreakaccidentwhereRCSpressurerapidlydropstonearatmospheric.
Accumulator andlowheadsafetyinjection (RHR)flowareimportant forthispostulated accident.
Forthisreason,smallchangesinHHSIpumpflowhaveanegligible effectonthelargeLOCAcalculated peakcladtemperature.
SmallBreakLOCAImactTheeffectofHHSI'reduction onsmallbreakLOCAisdetermined.
viaananalysiswiththeapprovedWsmallbreakLOCAevaluation modelnerformed onthe0.C.CookUnit1plant,whichwasanalyzedat3411MWtcorepower.Thecalculated PCTincreasederivedfromthisLOCAanalysisis86.1'F,calculated ontheworstbreaksize.Theinclusion ofthisPCTincreaseeffecttothebasePCTof1668'F(worstbreaksize)for0.C.CookUnit2yieldsavaluewellbelowthe10CFR50.46 limitof2200'FandislesslimitingthanthecurrentworstlargebreakPCT.Thesensit'ivi tyofPCTduetosmallHHSIflowreductions developed withD.C.CookUnit1isapplicable andboundingfor0.C.CookUnit2forthefollowing reasons:
1.Thetwoplants'ydraulic characteristics arenearlyidentical.
Theonlysignificant difference isUnit1has15x15fuelandUnit2has17x17fuel.Hutmoreimportantly thedifference infuelassemblyf1owareasbetweenthetwodesignsislesstha'n0.3%.2.TheeffectofreducedHHSIonthetransient ishydrau-.lic.Reduction inSIdiminishes theeffectsofbofloffreplenishing fnthecore.Thus,smallreduction indowncomer levelandcoremixtureheightwillresult.Thiseffectiswellbehavedandobservedthrough.smallLOCAanalysesperformed fornumerousplantsstudyingSleffects.3.Theeffectofareduction incoremixtureheightin-creasesthelengthofcoreuncovered andthustheenthalpyriseofthesteam.Thesteamenthalpyattheuncovered elevations determines cladtemperature sincethetransient isquasi-steady stateduringthecladheatupperiod.4.ThesmallLOCAanalysisforUnit1wasperformed at3411MMt,similartotheCookUnit2power.There-fore,theadditional enthalpyrisewillbecalculated correctly.
5.Theheatlineargeneration rateForUnit1isgreaterthanUnit2duetofewerfuelrods.Therefore, theeffectonPCTofreducedHHSIwillbemaximized.
6.Otherconservatisms intheanalysisexist.Forexample,thesmallLOCAanalysisforUnit2assumedanFgof2.32whiletheplantislimitedinoperation to2.04bylargebreakconsiderations.
Thisevaluation hasassessedtheimpactofreducedHHSIontheperformance oftheECCSattheD.C.CookUnit2plant.ThereducedHHSIhasamaximumimpactof86.1'Fonpeakcladtemperature forasmallLOCA.Theinclusion ofthisPCTincreasetothebasesmallLOCAPCTof1668'FforD.C.CookUnit2yieldsavaluewellbelowthe10CFR50.46 limitof2200'FandislesslimitingthanthecurrentworstlargebreakPCT.  


ComparisonofTotalSafetyInjectionFlowDeliveredtotheRCS(IncludesCharging,HHSIandLHSIWhereApplicable)RCSPressureSIa30ow(1b/s)60Minxow1b/s)14.7114.7140.7214.7414.7614.7814.71014.71214.71314.7p~510.7213.2105.0103.093.584.373+661.948.239.5509.3210.8103.3100.,591.181.470.659.045.436.6 APPENDIXOFADDITIONALRESULTSFROMTHE0.C.COOKUNIT1REDUCED(60GPMMINIFLOW)HHSIEYALUATION D.C.COOK1REDUCEDHHSISENSITIVITYSHALLBREAKTIMESEQUENCEOFEVENTS(SEC)EVENTTIME4IlICIISTARTREACTORTRIPSIGNALTOPOFCOREUNCOVERYACCUMULATORINJECTIONBEGINSPEAKCLADTEMPERATUREOCCURSTOPOFCORECOVERED0.017.5413.0800.0823.31310 D.C.COOKUNIT1REDUCEDHHSISENSITIVITY~~St1ALLBREAKRESULTSRESULTS4INCHPEAKCLADTEMPERATURE(oF)PEAKCLADTEMPERATURELOCATION(FT)LOCALZr/H20REACTION,HAXIHUM(X)LOCALZr/H20LOCATION(FT)TOTALZr/H20REACTION(X)HOTRODBURSTTINE(SEC)HOTRODBURSTLOCATION(FT)CALCULATION171611.750.9311.750.3NSSSPowerMWt102KofpeakLinearPowerkw/ft102KofHotRodPowerDistribution(AccumulatorHaterVolume,cu.ft.Fuelregion+cycleanalyzedUNIT1Cycle8341115.50950Region'klFUEL*SAMECOOKUNIT1CYCLE8RELOADSHALLBKANALYSIS R$00.0tS00.00CCOOKUNlflAEPSHBK4lsSKRCOUCESlSE~S3allRCSPRCSSUREOPSIAVl;O.F000.0.ih~~~VIl500.0y.~l000.0500.00~.04TFig.1TIHE(SEC)RCSPRESSURE-4IHDIA.CLBK II.OOOI2.S00CCOOKUllllIAEPSHSKIHSKAfDUCfSISfNS3iIIAfHEICHORlAiI0.000,Ll>l~'I75000R.SOOO1~r}llCkyl:rJlgl~.0Fig.28.88ChCITIHElSECI.COREflIXTUREHEIGHT-4INDIACLBK  
Comparison ofTotalSafetyInjection FlowDelivered totheRCS(Includes
: Charging, HHSIandLHSIWhereApplicable)
RCSPressureSIa30ow(1b/s)60Minxow1b/s)14.7114.7140.7214.7414.7614.7814.71014.71214.71314.7p~510.7213.2105.0103.093.584.373+661.948.239.5509.3210.8103.3100.,591.181.470.659.045.436.6 APPENDIXOFADDITIONAL RESULTSFROMTHE0.C.COOKUNIT1REDUCED(60GPMMINIFLOW)
HHSIEYALUATION D.C.COOK1REDUCEDHHSISENSITIVITY SHALLBREAKTIMESEQUENCEOFEVENTS(SEC)EVENTTIME4IlICIISTARTREACTORTRIPSIGNALTOPOFCOREUNCOVERYACCUMULATOR INJECTION BEGINSPEAKCLADTEMPERATURE OCCURSTOPOFCORECOVERED0.017.5413.0800.0823.31310 D.C.COOKUNIT1REDUCEDHHSISENSITIVITY
~~St1ALLBREAKRESULTSRESULTS4INCHPEAKCLADTEMPERATURE (oF)PEAKCLADTEMPERATURE LOCATION(FT)LOCALZr/H20REACTION, HAXIHUM(X)LOCALZr/H20LOCATION(FT)TOTALZr/H20REACTION(X)HOTRODBURSTTINE(SEC)HOTRODBURSTLOCATION(FT)CALCULATION 171611.750.9311.750.3NSSSPowerMWt102KofpeakLinearPowerkw/ft102KofHotRodPowerDistribution (Accumulator HaterVolume,cu.ft.Fuelregion+cycleanalyzedUNIT1Cycle8341115.50950Region'klFUEL*SAMECOOKUNIT1CYCLE8RELOADSHALLBKANALYSIS R$00.0tS00.00CCOOKUNlflAEPSHBK4lsSKRCOUCESlSE~S3allRCSPRCSSUREOPSIAVl;O.F000.0.ih~~~VIl500.0y.~l000.0500.00~.04TFig.1TIHE(SEC)RCSPRESSURE-4IHDIA.CLBK II.OOOI2.S00CCOOKUllllIAEPSHSKIHSKAfDUCfSISfNS3iIIAfHEICHORlAiI0.000,Ll>l~'I75000R.SOOO1~r}llCkyl:rJlgl~.0Fig.28.88ChCITIHElSECI.COREflIXTUREHEIGHT-4INDIACLBK  


5000.0DCCOOKUNlflAfPSHBKlNSKRCOUCCSlSCNS3illCLADAVC.ffHPNofRODBURST12.00foallPEAKll.lSfBel;w2500.0h~.'w'2000.0Ch4.-glSoo.ol000.0soo.oo0.0IfthhFig.38CChtlHElSCClHOTSPOTCLADTEt1PERATURF-4INOK 4$0.00$00.000CCOOK.:)IFlAEPSHQKIINQK.k(tjUCESlSENS311lSIEAHFlou<LBISEC~%0.00~85oIOO.OOX0.0-l00.00-200.00-)OO.OO-N0.008Fig.4lIHEDECICORESTElNFLO'lRATE4INBK  
5000.0DCCOOKUNlflAfPSHBKlNSKRCOUCCSlSCNS3illCLADAVC.ffHPNofRODBURST12.00foallPEAKll.lSfBel;w2500.0h~.'w'2000.0Ch4.-glSoo.ol000.0soo.oo0.0IfthhFig.38CChtlHElSCClHOTSPOTCLADTEt1PERATURF
-4INOK 4$0.00$00.000CCOOK.:)IFlAEPSHQKIINQK.k(tjUCE SlSENS311lSIEAHFlou<LBISEC~%0.00~85oIOO.OOX0.0-l00.00-200.00-)OO.OO-N0.008Fig.4lIHEDECICORESTElNFLO'lRATE4INBK  
,0C~,r}}
,0C~,r}}

Revision as of 09:01, 29 June 2018

Proposed Tech Specs Re Flowrate for Flow Balance Test of Safety Injection Pumps
ML17326B106
Person / Time
Site: Cook American Electric Power icon.png
Issue date: 03/15/1984
From:
INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:
Shared Package
ML17326B107 List:
References
NUDOCS 8403200214
Download: ML17326B106 (17)
v • d • e


Text

EMERGENCY CORECOOLINGSYSTEMSSURVEILLANCE REUIREMENTS Continued 2.Atleastonceper18months.BoronInjection ThrottleValvesValveNumberl.2-SI-141Ll2.2-SI-141L23.2-SI-141L34.2-SI-141L4SafetyInjection ThrottleValvesValveNumber1.2-SI-121N2.2-SI-121'Sh.Byperforming aflowbalancetestduringshutdownfollowing completion ofmodifications totheECCSsubsystem thatalterthesubsystem flowcharacteristics andverifying thefollowing flowrates:BoronInjection SystemSinlePuLoop1BoronInjection Flow117.5gpmLoop2BoronInjection Flow117.5gpmLoop3BoronInjection Flow117.5gpmLoop4BoronInjection Flow117.5gpmSafetyInjection SystemSinlePumo""Loop1and4ColdLeg.Flow>300@pmLoop2and3ColdLegFlow>300gpm**Combined Loop1,2,3and4ColdLegFlow(singlepump)<640gpm.TotalSIS(singlepump)flow,including miniflow,shallnotexceed700gpm.Amendment No."TheflowrateineachBoronInjection (BI)lineshouldbeadjustedtoprovide117.5gpm(nominal) flowintoeachloop.Undertheseconditions thereiszeromini-flow and80gpmsimulated RCPsealinjection lineflow.TheactualflowineachBIlinemaydeviatefromthenominalsolongasthedifference betweenthehighestandlowestflowis10gpmorlessandthetotalflowtothefourbranchlinesdoesnotexceed470gpm.Minimumflow(totalflow)requiredis345.8gpmtothethreemostconservative (lowest&low) branchlines.84032002i4 8403l5PDRADOCK05000316PPDR0.C.COOK-UNIT23/45-6 SPECIALTESTEXCEPTION POSITIONXNDXCATOR CHANNELSSKJTDONNLIMITINGCONDITION FOROPERATION 3.10.5Thelimitations ofSpecification 3.1.3.3maybesuspended duzingtheperformance ofindividual fulllength(shutdown andcontrol)roddroptimemeasuzements provided; a.Onlyoneshutdownorcontrolbankiswithdrawn fromthefullyinsertedpositionatatime,andb.Thegroupdemandpositionindicator isOPERABLEduringthewithdrawal oftherods.APPLICABILITY:

MODES3,4and5duringperformance ofroddroptlmemeasurements.

ACTION>liththegroupdemandpositionindicator inoperable, ormorethanonebankofrodswithdrawn, immediately openthereactortripbreakers.

SURVEILLANCE REQUIREMENTS 4.10.5Eachoftheaboverequiredgroupdemandpositionindicator(s) shallbedetexmined tobeOPERABLEbymovementoftheassociated shutdownorcontrolrodsatleast8stepsinanyonedirection within24hourspriortothestartoftherod,droptimemeasurements.

D.C.COOK-UNIT23/410-5 Mr.HaroldR.Dent-10-AEP:NRC:0860A~~ATTACHMENT 4TOAEP:NRC:0860A WESTINGHOUSE SUMMARYOFTHESAFETYEVALUATION FORINCREASED SZPUMPMINIFLOW LOCAEVALUATION FORD.C.COOKUNIT2WITHREDUCEDHIGHHEADSAFFTYINJECTION Thisevaluation assessestheimpactofreducedhighheadsafetyinjection onECCSperformance inresponsetoaLOCAforthe0.CCookUnit2plant.WSafeguards Systemsperformed anindependent calcula-tionevaluating theimpacttohighheadsafetyinjection

{HHSI)ofincmasing HHSIpumpminiflowfrom30gpmto60gpm.Thecalculation assumeda60gpmminiflowandthateachpairofcoldlegsreceivesgreaterthan300gpmduringflowbalancetesting.TheECCSflowrates werethencalculated usingthevendorperformance curvedegradedby5%ofdesignhead.Thetotaldelivered safetyinjection flowrates totheRCSforboth30gpmand60gpmareshowninTableI.Thereduction oft'otal'afetyinjection is-3-5Xintherangeof1200-600psiaimportant for'-this'valuation.

LareBreakLOCAImactHHSIpumpflowprovidesaninsignificant proportion ofthetotal6IflowduringalargebreakaccidentwhereRCSpressurerapidlydropstonearatmospheric.

Accumulator andlowheadsafetyinjection (RHR)flowareimportant forthispostulated accident.

Forthisreason,smallchangesinHHSIpumpflowhaveanegligible effectonthelargeLOCAcalculated peakcladtemperature.

SmallBreakLOCAImactTheeffectofHHSI'reduction onsmallbreakLOCAisdetermined.

viaananalysiswiththeapprovedWsmallbreakLOCAevaluation modelnerformed onthe0.C.CookUnit1plant,whichwasanalyzedat3411MWtcorepower.Thecalculated PCTincreasederivedfromthisLOCAanalysisis86.1'F,calculated ontheworstbreaksize.Theinclusion ofthisPCTincreaseeffecttothebasePCTof1668'F(worstbreaksize)for0.C.CookUnit2yieldsavaluewellbelowthe10CFR50.46 limitof2200'FandislesslimitingthanthecurrentworstlargebreakPCT.Thesensit'ivi tyofPCTduetosmallHHSIflowreductions developed withD.C.CookUnit1isapplicable andboundingfor0.C.CookUnit2forthefollowing reasons:

1.Thetwoplants'ydraulic characteristics arenearlyidentical.

Theonlysignificant difference isUnit1has15x15fuelandUnit2has17x17fuel.Hutmoreimportantly thedifference infuelassemblyf1owareasbetweenthetwodesignsislesstha'n0.3%.2.TheeffectofreducedHHSIonthetransient ishydrau-.lic.Reduction inSIdiminishes theeffectsofbofloffreplenishing fnthecore.Thus,smallreduction indowncomer levelandcoremixtureheightwillresult.Thiseffectiswellbehavedandobservedthrough.smallLOCAanalysesperformed fornumerousplantsstudyingSleffects.3.Theeffectofareduction incoremixtureheightin-creasesthelengthofcoreuncovered andthustheenthalpyriseofthesteam.Thesteamenthalpyattheuncovered elevations determines cladtemperature sincethetransient isquasi-steady stateduringthecladheatupperiod.4.ThesmallLOCAanalysisforUnit1wasperformed at3411MMt,similartotheCookUnit2power.There-fore,theadditional enthalpyrisewillbecalculated correctly.

5.Theheatlineargeneration rateForUnit1isgreaterthanUnit2duetofewerfuelrods.Therefore, theeffectonPCTofreducedHHSIwillbemaximized.

6.Otherconservatisms intheanalysisexist.Forexample,thesmallLOCAanalysisforUnit2assumedanFgof2.32whiletheplantislimitedinoperation to2.04bylargebreakconsiderations.

Thisevaluation hasassessedtheimpactofreducedHHSIontheperformance oftheECCSattheD.C.CookUnit2plant.ThereducedHHSIhasamaximumimpactof86.1'Fonpeakcladtemperature forasmallLOCA.Theinclusion ofthisPCTincreasetothebasesmallLOCAPCTof1668'FforD.C.CookUnit2yieldsavaluewellbelowthe10CFR50.46 limitof2200'FandislesslimitingthanthecurrentworstlargebreakPCT.

Comparison ofTotalSafetyInjection FlowDelivered totheRCS(Includes

Charging, HHSIandLHSIWhereApplicable)

RCSPressureSIa30ow(1b/s)60Minxow1b/s)14.7114.7140.7214.7414.7614.7814.71014.71214.71314.7p~510.7213.2105.0103.093.584.373+661.948.239.5509.3210.8103.3100.,591.181.470.659.045.436.6 APPENDIXOFADDITIONAL RESULTSFROMTHE0.C.COOKUNIT1REDUCED(60GPMMINIFLOW)

HHSIEYALUATION D.C.COOK1REDUCEDHHSISENSITIVITY SHALLBREAKTIMESEQUENCEOFEVENTS(SEC)EVENTTIME4IlICIISTARTREACTORTRIPSIGNALTOPOFCOREUNCOVERYACCUMULATOR INJECTION BEGINSPEAKCLADTEMPERATURE OCCURSTOPOFCORECOVERED0.017.5413.0800.0823.31310 D.C.COOKUNIT1REDUCEDHHSISENSITIVITY

~~St1ALLBREAKRESULTSRESULTS4INCHPEAKCLADTEMPERATURE (oF)PEAKCLADTEMPERATURE LOCATION(FT)LOCALZr/H20REACTION, HAXIHUM(X)LOCALZr/H20LOCATION(FT)TOTALZr/H20REACTION(X)HOTRODBURSTTINE(SEC)HOTRODBURSTLOCATION(FT)CALCULATION 171611.750.9311.750.3NSSSPowerMWt102KofpeakLinearPowerkw/ft102KofHotRodPowerDistribution (Accumulator HaterVolume,cu.ft.Fuelregion+cycleanalyzedUNIT1Cycle8341115.50950Region'klFUEL*SAMECOOKUNIT1CYCLE8RELOADSHALLBKANALYSIS R$00.0tS00.00CCOOKUNlflAEPSHBK4lsSKRCOUCESlSE~S3allRCSPRCSSUREOPSIAVl;O.F000.0.ih~~~VIl500.0y.~l000.0500.00~.04TFig.1TIHE(SEC)RCSPRESSURE-4IHDIA.CLBK II.OOOI2.S00CCOOKUllllIAEPSHSKIHSKAfDUCfSISfNS3iIIAfHEICHORlAiI0.000,Ll>l~'I75000R.SOOO1~r}llCkyl:rJlgl~.0Fig.28.88ChCITIHElSECI.COREflIXTUREHEIGHT-4INDIACLBK

5000.0DCCOOKUNlflAfPSHBKlNSKRCOUCCSlSCNS3illCLADAVC.ffHPNofRODBURST12.00foallPEAKll.lSfBel;w2500.0h~.'w'2000.0Ch4.-glSoo.ol000.0soo.oo0.0IfthhFig.38CChtlHElSCClHOTSPOTCLADTEt1PERATURF

-4INOK 4$0.00$00.000CCOOK.:)IFlAEPSHQKIINQK.k(tjUCE SlSENS311lSIEAHFlou<LBISEC~%0.00~85oIOO.OOX0.0-l00.00-200.00-)OO.OO-N0.008Fig.4lIHEDECICORESTElNFLO'lRATE4INBK

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