ML091390378

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Proposed Technical Specification Approach in Response to Generic Letter 2008-01
ML091390378
Person / Time
Site: Technical Specifications Task Force
Issue date: 05/19/2009
From: Coleman D, Mann B
PWR Owners Group, Technical Specifications Task Force
To:
Office of Nuclear Reactor Regulation
References
GL-08-001
Download: ML091390378 (5)
v • d • e


Text

Technical Specifications Task Force A Joint Owners Group Activity TSTF ProposedTechnicalSpecification ApproachinResponseto GenericLetter200801 DouglasColeman BWROGChairman BrianMann TechnicalSpecificationsTaskForce 1

5/19/2009

Technical Specifications Task Force A Joint Owners Group Activity TSTF

Background

  • GenericLetter(GL)200801waspublished becausetheNRChaspublished20 informationnotices,twoGLs,andaNUREG relatedtomanagementofentrainedgas,and eventscontinuedtooccur.
  • TechnicalSpecificationrequirementstoverify thesystemisfull(performedbyventing systemsinlimitedlocationsandonafixed frequency)didnotpreventtheseoccurrences.

Technical Specifications Task Force A Joint Owners Group Activity TSTF IndustryResponse

  • InresponsetotheGL,theindustryhas:

- FormedaGasAccumulationManagementTeam

- Fullindustryengagement:BWROG,PWROG,NEI,EPRI,INPO

- DevelopedOperabilityacceptancecriteria

- Conductedtestingongastransport

  • InresponsetotheGL,plantshave:

- Performeddetailedwalkdownsofsystemstoconfirmasbuilt configurations

- Determinedcriticallocationsandestablishedacceptancecriteria

- Implementednumerousimprovementsinplant:

  • Monitoringforgas
  • Processes(Operations,WorkManagement,OutagePlanning)
  • Procedures
  • Training
  • CorrectiveActionPrograms

Technical Specifications Task Force A Joint Owners Group Activity TSTF IndustryResponse

  • Theindustrysongoingeffortsinclude:

- Developinganindustryguidancedocumentonpreventing andmitigatingentrainedgas

- Developinggenericindustrytrainingmodulesonentrained gasmanagement

  • Atthispoint,theindustrybelievesthatwehave takenadequateactionstominimizeOperability impactsofentrainedgas.Ongoingplantspecific andindustryprogramswillcontinuetoenhanceand improvetheseefforts.

Technical Specifications Task Force A Joint Owners Group Activity TSTF IndustryResponse

  • GenericLetter200801,states,"theNRCstaffplans tousethisinformationduringactivitiesthatare beingplannedasafollowuptothisGLandfor guidanceintheTechnicalSpecificationsTaskForce programtodevelopimprovedTSs."
  • TheTSTFformedadvisoryteamsfromeachOwners GrouptodetermineappropriateTSchanges regardinggasmanagementinthesubjectsystems.

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Technical Specifications Task Force A Joint Owners Group Activity TSTF Evaluation

  • Theteamsevaluationstartedwiththe followingfacts:

- IntheGL,theNRCreferencedGeneralDesignCriteria (GDC)1,34,35,36,37,38,39,and40andQACriteriaIII,V, XI,XVI,andXVIIastheregulatorybasisforrequiring licenseestoensurethattheOperabilityofthesubject systemsisnotimpairedbyentrainedgas.

- TheNRCalsoreferencedcommitmentstootherQA documents,suchasRegGuide1.33whichrequires instructionsforfillingandventingtheECCSandDHR systems,aswellasfordrainingandrefillingheat exchangers.

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Technical Specifications Task Force A Joint Owners Group Activity TSTF Evaluation

- IntheGL,theNRCnotedthattheISTSandmostTScontain SRstoverifythatportionsofthesubjectsystemsarefullof water,butdidnotrelyonTScomplianceastheregulatory basisfortheGL.

  • Thescope&frequencyoftheverificationvariesbetweendesigns andplants,andsomeplantshavenosimilarTSrequirements.
  • TheTSrequiresverificationthatpipingisfullofwater,whichis subjecttointerpretation.
  • TheconclusionofanNRCTIAresponse,dated10/21/08,stated,in part:"Whenvoidsarediscoveredinpiping,ifthelicenseecan establishthroughanoperabilitydeterminationthatthereisa reasonableexpectationthatthesysteminquestionwillperformits specifiedsafetyfunction,thesystempipingcanbeconsideredfilled withwatersuchthatthesurveillancerequirementismet."

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Technical Specifications Task Force A Joint Owners Group Activity TSTF Evaluation

- ThedefinitionofOperabilitystates:

  • "Asystem,subsystem,train,component,ordeviceshall beOPERABLEorhaveOPERABILITYwhenitiscapable ofperformingitsspecifiedsafetyfunction(s)andwhen allnecessaryattendantinstrumentation,controls, normaloremergencyelectricalpower,coolingandseal water,lubrication,andotherauxiliaryequipmentthat arerequiredforthesystem,subsystem,[train/divison],

component,ordevicetoperformitsspecifiedsafety function(s)arealsocapableofperformingtheirrelated supportfunction(s)."

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Technical Specifications Task Force A Joint Owners Group Activity TSTF Evaluation

- TheNRC'sFinalPolicyStatementforTechnicalSpecification ImprovementsforNuclearPowerPlants(58FR39182) states:

  • "ThepurposeofTechnicalSpecificationsistoimposethose conditionsorlimitationsuponreactoroperationnecessaryto obviatethepossibilityofanabnormalsituationoreventgivingrise toanimmediatethreattothepublichealthandsafetyby identifyingthosefeaturesthatareofcontrollingimportanceto safetyandestablishingonthemcertainconditionsofoperation whichcannotbechangedwithoutpriorCommissionapproval.

(emphasisadded)

(continued) 9

Technical Specifications Task Force A Joint Owners Group Activity TSTF Evaluation

- TheFinalPolicyStatementonTechnicalSpecificationImprovement alsostates,"since1969therehasbeenatrendtowardsincluding intechnicalspecificationsnotonlythoserequirementsderivedfrom theanalysesandevaluationincludedintheplant'ssafetyanalysis reportbutalsoessentiallyallotherNRCrequirementsgoverningthe operationofnuclearpowerplants.IntheCommission'sview,this hasdivertedbothNRCstaffandlicenseeattentionfromthemore importantrequirementsinthesedocumentstotheextentthatit hasresultedinanadversebutunquantifiableimpactonsafety.

- TheISTS,whichweredevelopedinresponsetotheFinalPolicy Statement,retainedintheTechSpecsthoseparametersthatcanbe tiedbacktospecificsafetyanalysisassumptions,suchassetpoints, tankvolumes,pumpflowrates,etc.

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Technical Specifications Task Force A Joint Owners Group Activity TSTF Evaluation

  • Fromthesefacts,weconcluded:

- Averyhighstandardissetforaddingrequirementstothe TechnicalSpecifications.

- Therequirementtomanageentrainedgasisimposedon licenseesbyregulationsandTSOperabilityrequirementsto ensuresystemsarecapableofperformingtheirspecifiedsafety functions.

- TheStaffcorrectlyidentifiedtheappropriatebasisformanaging entrainedgas,whichis10CFR50,AppendixBandsystem Operability.

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Technical Specifications Task Force A Joint Owners Group Activity TSTF Evaluation

  • TheindustrybelievesanychangestotheTSto addressGL200801shouldbe:

1.

Sufficientlyflexibletoadjustthescope(includingwithin systems)andfrequencyofinspectionsbasedonpast performanceandplantspecificvulnerabilities.

- Evaluationshaveidentifiedawidevariationinthesusceptibilityto entrainedgasbetweenplants,systems,portionsofsystems,and operatingconditions.

2.

Sufficientlyflexibletoadjusttheacceptancecriteriaasneeded toensuresystemOperability.

- Theacceptancecriteriawillvarybyplant,system,location,andplant condition,andwillvaryovertimeasinspectionsareperformedand mitigatingactionsandvulnerabilitiesareidentified.

3.

AbletobesubmittedforNRCreviewwithoutincludingplant specificvariationsorevaluations.

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Technical Specifications Task Force A Joint Owners Group Activity TSTF Recommendation

  • TheteamrecommendsthattheexistingSRsbe removedandthemanagementoftheeffectsof entrainedgasontheOperabilitybecontrolledby:

- TheexistingTSrequirementthatasystembeOperable,and

- ThelicenseeactionsinresponsetoGL200801,e.g.,

improved:

  • Monitoringforgas
  • Processes
  • Procedures
  • Training
  • CorrectiveActionPrograms 13

Technical Specifications Task Force A Joint Owners Group Activity TSTF Justification

1. ASurveillanceisnotappropriateforthis application:

a)

Surveillancesrequireperformanceofspecific verificationstomeetstatedacceptancecriteriawithin fixedFrequencies.

b)

ImpositionofanSRwithspecificmethods,scope,and acceptancecriteriawouldlikelyresultinsubstantialover performanceofsomeactivitiesandunderperformance ofothers,dependingonplantdesign.

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Technical Specifications Task Force A Joint Owners Group Activity TSTF Justification

2. ATSAdministrativeControlsprogramis unnecessary:

a)

EntrainedgasisoneofmanyaspectsofOperability, mostofwhicharenotexplicitlystatedinTS,suchas coolingwater,flowbalancing,recirculationflow, componentintegrity,andlubrication.Theseare establishedandverifiedbylicenseedesigncontrol, operationsandmaintenanceprograms,allofwhichare subjecttotheQualityAssurancerequirements establishedin10CFR50,AppendixBandthedefinition ofOperability (continued) 15

Technical Specifications Task Force A Joint Owners Group Activity TSTF Justification 2.ATSAdministrativeControlsprogramis unnecessary:

b)

ATSAdministrativeControlsprogramwouldsimply restateexistingrequirementsasacknowledgedin responsestotheGenericLetter.

i.

Licenseeshavetakenactionstomonitorandmitigate entrainedgasinthespecifiedsystems.

ii.

IntheirresponsetotheGL,licenseeshavedocketed acknowledgmentoftherequirementstomanagegas accumulationaspartofsystemOperability.

iii.

ResponsestoGenericLettersbecomepartoftheplant's licensingbasis.

iv.

NRCmayinspectcompliancewiththoserequirements.

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Technical Specifications Task Force A Joint Owners Group Activity TSTF Justification

3. InothersimilarinstancesinwhichtheNRChas identifiedapotentialthreattosystemOperability, TScontrolshavenotbeenadded.

a)

Bulletin8503,"MotorOperatedValveCommonMode FailuresDuringPlantTransientsDuetoImproperSwitch Settings" b)

GenericLetter8712,"LossofResidualHeatRemoval (RHR)WhiletheSystem(RCS)isPartiallyFilled" c)

GenericLetter8817,"LossofDecayHeatRemoval" d)

GenericLetter8913,"ServiceWaterSystemProblems AffectingSafetyRelatedEquipment" (continued) 17

Technical Specifications Task Force A Joint Owners Group Activity TSTF Justification e)

GenericLetter9704,"AssuranceofSufficientNet PositiveSuctionHeadforEmergencyCoreCooling andContainmentHeatRemovalPumps f)

GenericLetter0402,PotentialImpactofDebris BlockageonEmergencyRecirculationduringDesign BasisAccidentsatPressurizedWaterReactors Licenseesrespondedtotheseissuesbyrevisinginspections, procedures,preventivemaintenancemeasures,etc.,without theadoptionofadditionalTSrequirements.

TheNRCinspectionprocess,theMaintenanceRule,andthe performanceindicatorshaveprovensufficienttoensurethese technicalissuesareaddressedwithoutimposingadditionalTS requirements.

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Technical Specifications Task Force A Joint Owners Group Activity TSTF Justification

4. IntheGL,theNRCdidnotrelyonTSrequirements asthebasisfortheneedtomanageentrainedgas ortodetermineOperabilityofthesubjectsafety systems.

TheNRC'sTIAresponse200803,datedOctober 21,2008,acknowledgedthattheexistingSRsare metbydeterminingsystemoperabilitythroughan operabilitydeterminationwhengasisfound.

Thisisthesameapproachwearesuggesting.

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Technical Specifications Task Force A Joint Owners Group Activity TSTF Conclusion

  • LicenseeresponsestoGenericLettershavehistoricallybeen effectiveinaddressingOperabilityconcerns.
  • NRCandindustryeffortstoaddressGL0801havebeen instrumentalinimprovinglicenseeawarenessofgas managementissues,resultinginsignificantimprovementofgas managementprograms.
  • AddingadditionalTSrequirementstoaddressentrainedgasis unnecessarytoensurethattheissueisadequatelyaddressed.
  • WebelievethatremovingtheexistingSR,combinedwiththe industryactions,clarifiestheroleofgasmanagementinsystem Operability.

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