ML17334A425

Documents Discussions on Request for License Amend Granting Relief from Requirements of Tech Spec 3.5.2 Re Safety Injection Pump Out of Svc.Safety Evaluation Prepared in Conjunction W/Westinghouse Supports Relief Request

ML17334A425
Person / Time
Site:	Cook
Issue date:	09/07/1982
From:	JURGENSEN R W AMERICAN ELECTRIC POWER SERVICE CORP.
To:	DENTON H R, VARGA S A NRC, Office of Nuclear Reactor Regulation
References
AEP:NRC:0739, AEP:NRC:739, NUDOCS 8209130234
Download: ML17334A425 (5)

Text

~~ANEPICANELECTR1CPGWERSe>viceCorpo~etio)s2Broadu:ay.Xeu:Pork,.l.}.Ir)00.t(2/2p.S>0.9000September7,1982AEP:NRC:0739DonaldC.CookNuclearPlantUnitNo.1DocketNo.50-315LicenseNo.DPR-58REQUESTFORRELIEFFROMTECHNICALSPECIFICATION3.5.2Mr.HaroldR.Denton,DirectorOfficeofNuclearReactorRegulationU.S.NuclearRegulatoryCommissionWashington,D.C.20555Attention:Mr.StevenA.'Varga

DearMr.Denton:

ThisletterdocumentsthediscussionsheldwithmembersofyourStaffconcerningourrequestforalicenseamendmentgrantingrelieffromtherequirementsof.TechnicalSpecification3.5.2.EachUnitoftheCookNuclearPlanthastwoSafetyInjectionPumpsplustwoCentrifugalChargingPumpsandtwoResidualHeatRemovalPumps.InpreparationfortheblackouttestperformedonAugust14,1982,UnitNo.1'sNorthSafetyInjectionPumpsufferedseveredamage.We",haveproceededtorepairthepumpexpeditiouslybuthavenotbeenabletocompletetherepairsasofthetimeofthisletter.UnitNo.1TechnicalSpecification(T/S)No.3.5.2requires,amongotherthings,thattwoSafetyInjection(SI)PumpsbeoperableinModes1,2and3.UnitNo.1iscurrently'completingitsrefuelingoutageandthereturntoModes3,2and1ispreventedbytheinoperabilityoftheSIpumpandtheT/Smentionedabove.Inordertoproceedwiththelowpowerphysicstesting,werequestawaiveroftherequirementtohavetwoSIpumpsoperableinModes2(reactorthermalpowerlessthanorequalto5%)and3foraperiodofoneweekbeginningatthetimetheUnitentersMode3.TheSouthSIpumpwillbedemonstratedoperablepriortoenteringMode3.Allremainingtechnicalspecificationrequirementswillbemet.Attachment1tothislettercontainsthesafetyevaluationpreparedbyusinconjunctionwithWestinghouse.Theconclusionisthatevenifweweretolosetheoperable1SSafetyInjectionPumpsufficientmarginKP wy,@5"-&~9'M~-'a wrMr.H.R.Dent.AEP:NRC:0739wouldstillexisttothelimitsspecifiedin10CFR50.46.Thus,thisreliefisnotdetrimentaltothehealthandsafetyofthepublic.IWewouldappreciatetheexpeditioushandlingofthisrequestbyyourStaff.AEPSCinterprets10CFR170.22asrequiringthataClassIIIAmendmentFeebepaidforthechange.Acheckintheamountof$4,000willbetransmittedtoyouinafutureletter.hThisTechnicalSpecificationreliefrequesthasbeenreviewedbytheCookPlantPNSRC.ItwillbereviewedbyAEPSC'sNSDRCatthenext~scheduledmeeting.Duetothisletterbeingwrittenonshortnotice,ithasnotbeenpreparedfollowingourstanda"dCorporateProceduresforsuchletters.Weshall,however,reviewtheletteraccordingtoourCorporateProceduresandwil'nformyouifanymodificationisrequired.Verytrulyyours,/emcAttachmentcc:JohnE.Dolan-ColumbusR.S.HunterM.P.AlexichW.G.Smith,Jr.-BridgmanR.C.CallenG.CharnoffJoeWilliams,Jr.NRCResidentInspectoratCookPlant-Bridgman'~~

AttachmenttoAEP:NRC:0739LOCAEvaluationforD.C.CookUnit1withOneSafetInectionPumOutofServiceThepurposeofthisevaluationistoassesstheeffectofonesafetyinjectionpumpoutofservicefortheCookUnit1NuclearPlantonLossofCoolantAccident(LOCA)consequences.Presently,theplantisfueledbyExxonNuclearCompany.However,theevaluationprovidedbelowisjudgedtobeapplicabletothenon'Westinghousefuel,sincetherearenoknownmajordesigndifferencesthatwouldhaveasignificantimpactontheLOCAbehaviorimportantforthisevaluation.LareBreakLOCASafetyinjectionpumpflowprovidesaninsignificantproportionofthetotalECCSflowduringalargebreakaccident,whereRCSpressurerapidlydropstonearatmospheric.Accumulatorandlowheadsafetyinjection(RHR)flowareimportantforthisaccident.Therefore,thelossofasafetyinjectionpumphasanegligibleeffectonlargeLOCAcalculatedpeakcladtemperature.SmallBreakLOCATheplant'sprotectionagainstsmallLOCAscomesfromatwotrainsystemincludingatotaloftwosafetyinjectionpumpsandtwohighheadchargingpumps.SmallLOCAFSARlicensinganalysesassumetheworstsinglefailuretobelossofatrain,leavingoneintermediateheadSIpumpandonechargingpump.ThesmallLOCAanalysisyieldscladtemperatureswellbelow10CFR50.46limits.Thisanalysisassumptionboundsthepresentplantconfigurationwithonesafetyinjectionpumpoutofserviceandnosinglefailure.Iftheworstsinglefailureassumptionisconsideredinadditiontothe;lossofthesafetyinjectionpump,andfurther,thetrainlostisassumed'tohavetheoperationalsafetyinjectionpump,ECCSflowisdeliveredfromonlythehighheadchargingpump.Thefollowingparagraphsevaluatethisscenario.ReductionofECCSflowintherangeof600to1200psiahasanadverse--"effectoncalculatedcladtemperatureforarangeofsmallLOCAbreaksizes.ThelossofasafetyinjectionpumphastheeffectofreducingdeliveredECCSflowinthatimportantpressurerange.TotalECCSflowwillbedegradedbyapproximately56%averagedoverthispressureinterval.Establishedsensitivitystudieshaveindicatedthatsuchadegradationresultsinasmuchasa550oFsmallLOCAPCTincrease.

~~0t~.ThesmallbreakanalysisforCook1doesnotusethelatestNRCapprovedWsmallLOCAEvaluationModel.ThecurrentsmallbreakLOCAEMwouldcalculateaPCTofapproximately1200oF,reducedfrom1493F,predictedbytheanalysisintheFSAR.ThisnewPCTisestablishedfromanalysisofasubstantiallyequivalentplant(3250MWt,4Loop,sameSISdesign)analyzedinHCAP-8970-P-A,,"WestinghouseEmergencyCoreCo'olingSystemSmall8reakOctober,1975Model",andappliestoCook.Additionally,creditforconservativeassumptionsinthesmallLOCAFSARanalysiscanmitigatethePCTpenalty.Also,thecurrentsmallLOCAFSARanalysisisperformedat100%powerwhileduringtheperiodoftimeforwhichweareseekingT/Sreliefthereactorwillnotexceed5%power.Thelowerpower.levelof5%versus100%wouldmorethanoffsettheconsequencesofreducedECCSflow.Inconclusion,operationofCook1withasafetyinjectionpumpoutofserviceandamaximumpowerlevelof5%forabrief'periodoftimeisstillboundedbythesmallLOCAFSARanalysis.Inaddition,thefactthatthepresentanalysishassignificantmarginto10CFR50.46PCTlimitsindicatesthatstartupoftheplantfromthisrefuelingoutageisnotasafetyconcern.