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

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Xeu:Pork,.l.}.Ir)00.t(2/2p.S>0.9000September 7,1982AEP:NRC:0739 DonaldC.CookNuclearPlantUnitNo.1DocketNo.50-315LicenseNo.DPR-58REQUESTFORRELIEFFROMTECHNICAL SPECIFICATION 3.5.2Mr.HaroldR.Denton,DirectorOfficeofNuclearReactorRegulation U.S.NuclearRegulatory Commission Washington, D.C.20555Attention:

Mr.StevenA.'Varga

DearMr.Denton:

Thisletterdocuments thediscussions heldwithmembersofyourStaffconcerning ourrequestforalicenseamendment grantingrelieffromtherequirements of.Technical Specification 3.5.2.EachUnitoftheCookNuclearPlanthastwoSafetyInjection PumpsplustwoCentrifugal ChargingPumpsandtwoResidualHeatRemovalPumps.Inpreparation fortheblackouttestperformed onAugust14,1982,UnitNo.1'sNorthSafetyInjection Pumpsufferedseveredamage.We",haveproceeded torepairthepumpexpeditiously buthavenotbeenabletocompletetherepairsasofthetimeofthisletter.UnitNo.1Technical Specification (T/S)No.3.5.2requires, amongotherthings,thattwoSafetyInjection (SI)PumpsbeoperableinModes1,2and3.UnitNo.1iscurrently

'completing itsrefueling outageandthereturntoModes3,2and1isprevented bytheinoperability oftheSIpumpandtheT/Smentioned above.Inordertoproceedwiththelowpowerphysicstesting,werequestawaiveroftherequirement tohavetwoSIpumpsoperableinModes2(reactorthermalpowerlessthanorequalto5%)and3foraperiodofoneweekbeginning atthetimetheUnitentersMode3.TheSouthSIpumpwillbedemonstrated operablepriortoenteringMode3.Allremaining technical specification requirements willbemet.Attachment 1tothislettercontainsthesafetyevaluation preparedbyusinconjunction withWestinghouse.

Theconclusion isthatevenifweweretolosetheoperable1SSafetyInjection Pumpsufficient marginKP wy,@5"-&~9'M

~-'a wrMr.H.R.Dent.AEP:NRC:0739wouldstillexisttothelimitsspecified in10CFR50.46.Thus,thisreliefisnotdetrimental tothehealthandsafetyofthepublic.IWewouldappreciate theexpeditious handlingofthisrequestbyyourStaff.AEPSCinterprets 10CFR170.22asrequiring thataClassIIIAmendment Feebepaidforthechange.Acheckintheamountof$4,000willbetransmitted toyouinafutureletter.hThisTechnical Specification reliefrequesthasbeenreviewedbytheCookPlantPNSRC.ItwillbereviewedbyAEPSC'sNSDRCatthenext~scheduled meeting.Duetothisletterbeingwrittenonshortnotice,ithasnotbeenpreparedfollowing ourstanda"dCorporate Procedures forsuchletters.Weshall,however,reviewtheletteraccording toourCorporate Procedures andwil'nform youifanymodification isrequired.

Verytrulyyours,/emcAttachment cc:JohnE.Dolan-ColumbusR.S.HunterM.P.AlexichW.G.Smith,Jr.-BridgmanR.C.CallenG.CharnoffJoeWilliams, Jr.NRCResidentInspector atCookPlant-Bridgman'~~

Attachment toAEP:NRC:0739 LOCAEvaluation forD.C.CookUnit1withOneSafetInectionPumOutofServiceThepurposeofthisevaluation istoassesstheeffectofonesafetyinjection pumpoutofservicefortheCookUnit1NuclearPlantonLossofCoolantAccident(LOCA)consequences.

Presently, theplantisfueledbyExxonNuclearCompany.However,theevaluation providedbelowisjudgedtobeapplicable tothenon'Westinghouse fuel,sincetherearenoknownmajordesigndifferences thatwouldhaveasignificant impactontheLOCAbehaviorimportant forthisevaluation.

LareBreakLOCASafetyinjection pumpflowprovidesaninsignificant proportion ofthetotalECCSflowduringalargebreakaccident, whereRCSpressurerapidlydropstonearatmospheric.

Accumulator andlowheadsafetyinjection (RHR)flowareimportant forthisaccident.

Therefore, thelossofasafetyinjection pumphasanegligible effectonlargeLOCAcalculated peakcladtemperature.

SmallBreakLOCATheplant'sprotection againstsmallLOCAscomesfromatwotrainsystemincluding atotaloftwosafetyinjection pumpsandtwohighheadchargingpumps.SmallLOCAFSARlicensing analysesassumetheworstsinglefailuretobelossofatrain,leavingoneintermediate headSIpumpandonechargingpump.ThesmallLOCAanalysisyieldscladtemperatures wellbelow10CFR50.46limits.Thisanalysisassumption boundsthepresentplantconfiguration withonesafetyinjection pumpoutofserviceandnosinglefailure.Iftheworstsinglefailureassumption isconsidered inadditiontothe;lossofthesafetyinjection pump,andfurther,thetrainlostisassumed'tohavetheoperational safetyinjection pump,ECCSflowisdelivered fromonlythehighheadchargingpump.Thefollowing paragraphs evaluatethisscenario.

Reduction ofECCSflowintherangeof600to1200psiahasanadverse--"effect oncalculated cladtemperature forarangeofsmallLOCAbreaksizes.Thelossofasafetyinjectionpumphastheeffectofreducingdelivered ECCSflowinthatimportant pressurerange.TotalECCSflowwillbedegradedbyapproximately 56%averagedoverthispressureinterval.

Established sensitivity studieshaveindicated thatsuchadegradation resultsinasmuchasa550oFsmallLOCAPCTincrease.

~~0t~.ThesmallbreakanalysisforCook1doesnotusethelatestNRCapprovedWsmallLOCAEvaluation Model.ThecurrentsmallbreakLOCAEMwouldcalculate aPCTofapproximately 1200oF,reducedfrom1493F,predicted bytheanalysisintheFSAR.ThisnewPCTisestablished fromanalysisofasubstantially equivalent plant(3250MWt,4Loop,sameSISdesign)analyzedinHCAP-8970-P-A,

,"Westinghouse Emergency CoreCo'olingSystemSmall8reakOctober,1975Model",andappliestoCook.Additionally, creditforconservative assumptions inthesmallLOCAFSARanalysiscanmitigatethePCTpenalty.Also,thecurrentsmallLOCAFSARanalysisisperformed at100%powerwhileduringtheperiodoftimeforwhichweareseekingT/Sreliefthereactorwillnotexceed5%power.Thelowerpower.levelof5%versus100%wouldmorethanoffsettheconsequences ofreducedECCSflow.Inconclusion, operation ofCook1withasafetyinjection pumpoutofserviceandamaximumpowerlevelof5%forabrief'periodoftimeisstillboundedbythesmallLOCAFSARanalysis.

Inaddition,thefactthatthepresentanalysishassignificant marginto10CFR50.46PCTlimitsindicates thatstartupoftheplantfromthisrefueling outageisnotasafetyconcern.