ML14182A099

From kanterella
Jump to: navigation, search
July 1, 2014 Public Meeting Slides TVA - NTTF 2.1 - Seismic Reevaluation - GMRS
ML14182A099
Person / Time
Site: Watts Bar Tennessee Valley Authority icon.png
Issue date: 07/01/2014
From:
Tennessee Valley Authority
To:
Office of Nuclear Reactor Regulation
Balazik M F, NRR/JLD, 415-2856
References
Download: ML14182A099 (40)


Text

Information Exchange WBN Seismic Hazard 1

Information Exchange WBN Seismic Hazard

  • NRC May 9 Prioritization Letter-Seismic Risk Evaluation *Prioritization Group 1-WBN Acknowledges *Prioritization Group 1*Seismic risk evaluation by June 30, 2017
  • ESEP -RLGM -2 x SSE
  • NRC May 21 Support Document-Preliminary graphical representation*NRC staff GMRS differs from Licensee GMRS 2

Information Exchange WBN Seismic Hazard EPRIMaximum: 0.77g@15HzNRCMaximum: 0.98@30Hz 3 Information Exchange WBN Seismic Hazard

  • WBNunderstandingofthecausesoftheprimarydifferencesbetweenthepreliminaryNRCandlicenseeresults.*ElementsofNRCstaffpreliminaryassessment
  • FSARprimarysourceforinformationonsubsurfacematerials-narrowervelocityprofile>>4,500fpslower>>6,500fpsupper-Hardrockat1,000ft.*UseofEPRIrockcurvesandlowstraindampingvalues*KappaValuesandweights 4 Information Exchange WBN Seismic Hazard
  • WBNadditionaldataforsubsurfacematerials*Expandsitegeologicprofileduetocurrentunderstandingofhardrockcharacteristics-shearwavevelocity>9200fps.*Reduceuncertaintythroughoutprofiletobasement>10,000ft.*SupportEPRIGMRSDevelopment*SupportDevelopmentofSeismicHazardinputforSPRA 5 Information Exchange WBN Seismic Hazard
  • UtilizedAcademic/IndustryExpertise-AMEC-ProgramManagement;regional/localgeology-Dr.RobertHatcher,ProfessorofGeology,UniversityofTennessee-Knoxville>>Regional/localgeology-Dr.KenStokoe,ProfessorofCivilEngineering,UniversityofTexas-Austin>>SpectraAnalysisSurfaceWave(SASW)Survey>>RockTesting-IvanWong(URS)and>>SeismicHazard&EvaluationofSASW/RockTesting-WaltSilva(PE&A)>>SiteModeling/Characterization

-FacilityRiskConsultants>>3 rd partyseismicconsultantreview 6 Information Exchange WBN Seismic Hazard Source:AMEC(2013)7 Information Exchange WBN Seismic Hazard 8

Information Exchange WBN Seismic Hazard 9

Information Exchange WBN Seismic Hazard 10 Information Exchange WBN Seismic Hazard

  • SASWSurvey(8testsites)-Sites6&7profileddepthsofapprox.1400'and1700'-SASWTeambelievesresultsfromSite8wouldhavebeensimilarhadsufficientlateralspacebeenavailableforalongersurveyline.-Achievingprofiledepthsof1400 1700'isuncommonlygoodresultsforSASWsurvey!*RockTesting-6IntactRockCores(URCfreefreeunconfinedresonantcolumntests)-PumpkinValleyShale(2),ConsaugaMiddle,PondSpringsFormation,NolichuckyShale,andRomeFormation 11 Information Exchange WBN Seismic Hazard Source:AMEC(2013)12 Information Exchange WBN Seismic Hazard
  • BenefitsDerivedfromSASWSurvey/RockTesting-Providedshear wavevelocitydataforimportantgeologicformationsbeneaththesite-Capturedthevariabilityinshear wavevelocitybeneaththesite-Providedsite specificmeasurementswhichreducedtheepistemicuncertaintyintheprofiles(1.25whereappropriate)

-Demonstratesthatassumptionsofshear wavevelocitiesfromthetypeofrockwouldhavebeenmisleading.Forexample,itwassurprisingthattheRomesandstonewasasfastasitwasandthedolomiteslowerthanwasthought.Nosubstituteforrealdata!-SASWmeasurementswereperformedtoadepthupto1700ftrightnexttothereactor,someofthedeepestmeasurementstakeninthecentralandeasternUS.13 Information Exchange WBN Seismic HazardFigure2.3.2 1Shear wavevelocityprofilesforWattsBarNuclearPlant(EPRI,2014)BaseCase600'LowerBound600'UpperBound592'UpperBound936'LowerBound936'BaseCase936'14 Information Exchange WBN Seismic Hazard

  • DevelopmentOfTotalEffectiveKappa-FollowingSPIDGuidelinesForFirmRockProfile<3,000ftDeep-TotalEffectiveKappaBasedonFirmRockDampingof1.25%(Q S=40)-PlusHardRockContribution0.006s*UncertaintyInDepthToHardRockAccommodatedWithTwoMeanDepths600ft,900ft-ResultsInSixKappaEstimatesForBase Case,UpperRange,LowerRangeProfilesandTwoDepthstoHardRock 15 Information Exchange WBN Seismic Hazard
  • EpistemicUncertaintyInBase CaseV SProfilesOf1.25ResultsInNarrowRangeOfKappa-FollowingSPIDGuidelines,EpistemicUncertaintyInKappaTakenasln 0.4AboutMeanEstimate-ShallowProfile0.012s+/-,range0.007sto0.020s-DeepProfile0.013s+/-,range0.008sto0.022s 16 Information Exchange WBN Seismic Hazard
  • Summary-WattsBardevelopedasignificantlyenhancedsitegeologicalprofiletosupportsitecharacterization

-SupplementedbySASWsurveytoprovideadditionalclarityforstrataaboveTopofHardRock-AccountsforvariationinthetopoftheRomeFormationunderlyingWBN-Rocktestingof6intactcorestodetermineparametersforsitecharacterization

-SitecharacterizationandEPRIGMRSperformedinconformancewithSPIDandisappropriatecharacterizationofseismichazardforWattsBarsite.17 Information Exchange SQN Seismic Hazard 1

Information Exchange SQN Seismic Hazard*NRC May 9 Prioritization Letter-Seismic Risk Evaluation *Prioritization Group 2-SQN Acknowledges *Prioritization Group 2*Seismic risk evaluation by December 31, 2019

  • ESEP -RLGM = 2 x SSE*NRC May 21 Support Document-Preliminary graphical representation*NRC staff GMRS differs from Licensee GMRS 2

Information Exchange SQN Seismic Hazard EPRIMaximumSA: 0.76g@20HzNRCMaximumSA: 0.84g@40Hz 3 Information Exchange SQN Seismic Hazard

  • SQNunderstandingofthecausesoftheprimarydifferencesbetweenthepreliminaryNRCandlicenseeresults.*ElementsofNRCstaffpreliminaryassessment
  • Velocityprofile*UseofEPRIrockcurvesandlowstraindampingvalues*KappaValuesandweights 4 Information Exchange SQN Seismic Hazard
  • SQNadditionaldataforsubsurfacematerials*Expandsitegeologicprofileduetocurrentunderstandingofhardrockcharacteristics-shearwavevelocity>9200fps.*FSARhadlimitedrockcharacteristicsdataavailableatdepth(>103ft)*Definitionofrockprofiletobasement12,000ft.*SupportEPRIGMRSDevelopment5 Information Exchange SQN Seismic Hazard
  • UtilizedAcademic/IndustryExpertise-AMEC-ProgramManagement;regional/localgeology-Dr.RobertHatcher,ProfessorofGeology,UniversityofTennessee-Knoxville

>>Regional/localgeology-Dr.KenStokoe,ProfessorofCivilEngineering,UniversityofTexas-Austin>>SpectraAnalysisSurfaceWave(SASW)Survey@WBN>>RockTesting-IvanWong(URS)>>SiteModeling/Characterization 6

Information Exchange SQN Seismic Hazard Source:AMEC(2013)7 Information Exchange SQN Seismic HazardFigure2.3.2 1Shear wavevelocityprofilesforSequoyahNuclearPlant(EPRI,2014)0500100015002000250030003500400045005000550060006500010002000300040005000600070008000900010000Depth(ft)Vs(ft/sec)VsprofilesforSequoyahSiteProfile1Profile2Profile3 BaseCaseLowerBound UpperBound 8 Information Exchange SQN Seismic Hazard

  • DevelopmentofTotalEffectiveKappa*FollowingSPIDGuidelinesForFirmRockProfile>3,000ftDeep-TotalEffectiveKappaBasedonAvg.V S overTop100ft,SurfaceOutcrop-P16,000ft/s,0.012s-P23,821ft/s,0.020s-P39,285ft/s,0.006sHardRock-LikelyConservative(low),0to40ftSoil,NoWeatheredZone*Range0.006sto0.020sConsideredSufficientExpressionOfEpistemicUncertainty 9

Information Exchange SQN Seismic Hazard

  • Summary-Sequoyahdevelopedanenhancedsitegeologicalprofile*Supplementedbyregionalgeologymaps,industryexperts,andnearbySASWsurveys-EPRIGMRSandsitecharacterizationperformedinconformancewithSPIDandisappropriatecharacterizationofseismichazardforSequoyahsite.10 Information ExchangeBFN Seismic Hazard 11 Information Exchange BFN Seismic Hazard*NRC May 9 Prioritization Letter-Seismic Risk Evaluation *Prioritization Group 2*NRC May 21 Support Document-Preliminary graphical representation*NRC staff GMRS differs from Licensee GMRS 12 Information Exchange BFN Seismic Hazard LicenseeMaximumSA:

0.58g@25HzNRCMaximumSA: 0.68g@40Hz 13 Information Exchange BFN Seismic Hazard

  • BFNunderstandingofthecausesoftheprimarydifferencesbetweenthepreliminaryNRCandlicenseeresults.*ElementsofNRCstaffpreliminaryassessment
  • Narrowervelocityprofile-7,000fpslowerbound-9,285fpsupperbound(hardrock)*UseofEPRIrockcurvesandlowstraindampingvalues*KappaValuesandweights 14 Information Exchange BFN Seismic Hazard
  • BFNadditionaldataforsubsurfacematerials*Expandsitegeologicprofileduetocurrentunderstandingofhardrockcharacteristics-shearwavevelocity>9200fps.*FSARhadlimitedrockcharacteristicsdataavailableatdepth(>200ft)*Definitionofrockprofiletobasement5,000ft.*SupportEPRIGMRSDevelopment15 Information Exchange BFN Seismic Hazard
  • UtilizedAcademic/IndustryExpertise-AMEC-ProgramManagement;regional/localgeology-Dr.RobertHatcher,ProfessorofGeology,UniversityofTennessee-Knoxville

>>Regional/localgeology-Dr.KenStokoe,ProfessorofCivilEngineering,UniversityofTexas-Austin>>SpectraAnalysisSurfaceWave(SASW)Survey@WBN>>RockTesting-IvanWong(URS)>>SiteModeling/Characterization 16 Information Exchange BFN Seismic Hazard Source:AMEC(2013)17 Information Exchange BFN Seismic HazardFigure2.3.2 1Shear wavevelocityprofilesforBrownsFerryNuclearPlant(EPRI,2014)VsprofilesforBrownsFerrySite BaseCaseLowerBound UpperBound 18 Information Exchange BFN Seismic Hazard

  • DevelopmentofTotalEffectiveKappa*FollowingSPIDGuidelinesForFirmRockProfile>3,000ft Deep-TotalEffectiveKappaBasedonAvg.VsOverTop100ft,surfaceoutcrop-ProfilesP1,P3HardRockNearSurface,=0.006s-ProfileP2Vs(100ft)5,914ft/s,=0.012s-LikelyConservative(low),0to50ftSoil,NoWeatheredZone*Range0.006sto0.012sConsideredSufficientExpressionofEpistemicUncertainty19 Information Exchange BFN Seismic Hazard
  • Summary-BrownsFerrydevelopedanenhancedsitegeologicalprofile*Supplementedbyregionalgeologymapsandindustryexperts-EPRIGMRSandsitecharacterizationperformedinconformancewithSPIDandisappropriatecharacterizationofseismichazardforBrownsFerrysite.20 BFN Seismic Risk Evaluation Screening Results 21
  • BFNunderstandstheIPEEEevaluationdidnotmeetNRCstaffsexpectationforscreeningpurposes-Prerequisite #3-Adequacy Demonstration #3*BFN adequacy review acknowledged the SER identified weakness and provided justification for

addressing the weakness as part of the ESEP

  • BFNhassubsequentlycompletedseismiccapacityevaluationsfortheadditionalRCICcomponents-Minimum HCLPF > 0.50g Information Exchange BFN Seismic Hazard*Additional information-BFN reevaluated minimum HCLPF SSC (Auxiliary Diesel Generator Transformers)*HCLPF > 0.30g in current configuration and replacement configuration*BFN commitment to complete transformer replacement by Sept 30, 2014 to resolve PCB/IPEEE screening capacity *TVA requests that the NRC staff reconsider the May 9, 2014 screening result that BFN screens

in for seismic risk evaluation