CNL-14-211, Expedited Seismic Evaluation Process Report (CEUS Sites) Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima

Expedited Seismic Evaluation Process Report (CEUS Sites) Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima

ML14365A055
Person / Time
Site:	Sequoyah   (DPR-077, DPR-079)
Issue date:	12/22/2014
From:	James Shea Tennessee Valley Authority
To:	Document Control Desk, Division of Operating Reactor Licensing
References
CNL-14-211
Download: ML14365A055 (64)

Text

Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402 CNL-14-211 December 22, 2014 10 CFR 50.4 10 CFR 50.54(f)

Attn: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001

Sequoyah Nuclear Plant, Units 1 and 2 Facility Operating License Nos. DPR-77 and DPR-79 NRC Docket Nos. 50-327 and 50-328

Subject:

Tennessee Valley Authoritys Sequoyah Nuclear Plant Expedited Seismic Evaluation Process Report (CEUS Sites) Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident

References:

NRC Letter, Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendations 2.1, 2.3, and 9.3, of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated March 12, 2012 (ML12056A046)

On March 12, 2012, the U.S. Nuclear Regulatory Commission (NRC) issued the referenced letter to all power reactor licensees and holders of construction permits in active or deferred status. Enclosure 1 of the referenced letter requested each addressee located in the Central and Eastern United States (CEUS) to submit a Seismic Hazard Evaluation that includes an interim evaluation and actions taken or planned to address the higher seismic hazard relative to the design basis, as appropriate, prior to completion of the risk evaluation.

In accordance with the referenced letter above, TVA is enclosing the Expedited Seismic Evaluation Process (ESEP) Report for Sequoyah Nuclear Plant.

provides a list of new regulatory commitments as described in Section 8.0 of the enclosed ESEP Report.

U.S. Nuclear Regulatory Commission CNL-14-211 Page 2 December 22, 2014 Should you have any questions concerning the content of this letter, please contact Kevin Casey at (423) 751-8523.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 22nd day of December 2014.

. Shea President, Nuclear Licensing

Enclosures:

1. Expedited Seismic Evaluation Process (ESEP) Report for Sequoyah Nuclear Plant

2. List of Commitments cc (Enclosures):

NRR Director-NRC Headquarters NRO Director - NRC Headquarters NRR JLD Director-NRC Headquarters NRC Regional Administrator - Region II NRR Project Manager - Sequoyah Nuclear Plant NRR JLD Project Manager-Sequoyah Nuclear Plant NRC Senior Resident Inspector-Sequoyah Nuclear Plant

ENCLOSURE 1 EXPEDITED SEISMIC EVALUATION PROCESS (ESEP) REPORT FOR SEQUOYAH NUCLEAR PLANT

Page1 EXPEDITED SEISMIC EVALUATION PROCESS (ESEP) REPORT FOR SEQUOYAH NUCLEAR PLANT

SequoyahNuclearPlantESEPReport Page2 TableofContents Page LISTOFTABLES............................................................................................................................................4 LISTOFFIGURES..........................................................................................................................................5 1.0 PURPOSEANDOBJECTIVE...............................................................................................................6 2.0 BRIEF

SUMMARY

OFTHEFLEXSEISMICIMPLEMENTATIONSTRATEGIES......................................6 3.0 EQUIPMENTSELECTIONPROCESSANDESEL..................................................................................8 3.1 EquipmentSelectionProcessandESEL..............................................................................8 3.1.1 ESELDevelopment...............................................................................................9 3.1.2 PowerOperatedValves.....................................................................................10 3.1.3 PullBoxes...........................................................................................................10 3.1.4 TerminationCabinets.........................................................................................10 3.1.5 CriticalInstrumentationIndicators....................................................................10 3.1.6 Phase2and3PipingConnections.....................................................................10 3.2 JustificationforUseofEquipmentThatisNotthePrimaryMeansforFLEX Implementation................................................................................................................11 4.0 GROUNDMOTIONRESPONSESPECTRUM(GMRS)......................................................................11 4.1 PlotofGMRSSubmittedbytheLicensee.........................................................................11 4.2 ComparisontoSSE............................................................................................................13 5.0 REVIEWLEVELGROUNDMOTION(RLGM)...................................................................................14 5.1 DescriptionofRLGMSelected..........................................................................................14 5.2 MethodtoEstimateInStructureResponseSpectra(ISRS)..............................................15 6.0 SEISMICMARGINEVALUATIONAPPROACH.................................................................................17 6.1 SummaryofMethodologiesUsed....................................................................................17 6.2 HCLPFScreeningProcess..................................................................................................18 6.3 SeismicWalkdownApproach...........................................................................................19 6.3.1 WalkdownApproach..........................................................................................19 6.3.2 ApplicationofPreviousWalkdownInformation...............................................20 6.3.3 SignificantWalkdownFindings..........................................................................20 6.4 HCLPFCalculationProcess................................................................................................21 6.5 FunctionalEvaluationsofRelays......................................................................................21 6.6 TabulatedESELHCLPFValues(IncludingKeyFailureModes)..........................................22 7.0 INACCESSIBLEITEMS.....................................................................................................................22 7.1 IdentificationofESELItemInaccessibleforWalkdowns..................................................22 7.2 PlannedWalkdown/EvaluationSchedule/CloseOut....................................................23 8.0 ESEPCONCLUSIONSANDRESULTS...............................................................................................24 8.1 SupportingInformation....................................................................................................24

SequoyahNuclearPlantESEPReport TableofContents (continued)

Page Page3 8.2 IdentificationofPlannedModifications...........................................................................25 8.3 ModificationImplementationSchedule...........................................................................25 8.4 SummaryofRegulatoryCommitments............................................................................26

9.0 REFERENCES

..................................................................................................................................27 ATTACHMENTA-SEQUOYAHNUCLEARPLANTESEL.............................................................................A1 ATTACHMENTB-ESEPHCLPFVALUESANDFAILUREMODESTABULATIONFORSEQUOYAH NUCLEARPLANT.........................................................................................................B1

SequoyahNuclearPlantESEPReport Page4 List of Tables Page TABLE41:GMRSFORSEQUOYAHNUCLEARPLANT...............................................................................11 TABLE42:SSEFORSEQUOYAHNUCLEARPLANT...................................................................................13 TABLE51:2XSSEFORSEQUOYAHNUCLEARPLANT..............................................................................15 TABLE81:

SUMMARY

OFREGULATORYCOMMITMENTS......................................................................26 TABLEA1:EXPEDITEDSEISMICEQUIPMENTLIST(ESEL)FORSEQUOYAHNUCLEARPLANT................A2 TABLEB1:ESEPHCLPFVALUESANDFAILUREMODESFORSEQUOYAHNUCLEARPLANT...................B2

SequoyahNuclearPlantESEPReport Page5 List of Figures Page FIGURE41:GMRSFORSEQUOYAHNUCLEARPLANT.............................................................................12 FIGURE42:GMRSTOSSECOMPARISONFORSEQUOYAHNUCLEARPLANT.........................................14 FIGURE51:2XSSEFORSEQUOYAHNUCLEARPLANT............................................................................15 FIGURE52:NUREG/CR0098(0.3G)VERSUSSEQUOYAHNUCLEARPLANTSSE....................................16 FIGURE61:84THPERCENTILEOFTHEENSEMBLEOFTHE30RESPONSESPECTRA..............................18 FIGURE62:SEQUOYAHNUCLEARPLANTIPEEEADJUSTEDHCLPFVSESEPTARGETHCLPF..................18

SequoyahNuclearPlantESEPReport Page6 1.0 PURPOSEANDOBJECTIVE FollowingtheaccidentattheFukushimaDaiichinuclearpowerplantresultingfromtheMarch11, 2011,GreatTohokuEarthquakeandsubsequenttsunami,theNuclearRegulatoryCommission(NRC) establishedaNearTermTaskForce(NTTF)toconductasystematicreviewofNRCprocessesand regulationsandtodetermineiftheagencyshouldmakeadditionalimprovementstoitsregulatory system.TheNTTFdevelopedasetofrecommendationsintendedtoclarifyandstrengthenthe regulatoryframeworkforprotectionagainstnaturalphenomena.Subsequently,theNRCissueda 50.54(f)letteronMarch12,2012[1],requestinginformationtoassurethattheserecommendations areaddressedbyallU.S.nuclearpowerplants.The50.54(f)letterrequeststhatlicenseesandholders ofconstructionpermitsunder10CFRPart50reevaluatetheseismichazardsattheirsitesagainst presentdayNRCrequirementsandguidance.Dependingonthecomparisonbetweenthereevaluated seismichazardandthecurrentdesignbasis,furtherriskassessmentmayberequired.Assessment approachesacceptabletothestaffincludeaseismicprobabilisticriskassessment(SPRA),oraseismic marginassessment(SMA).Basedupontheassessmentresults,theNRCstaffwilldeterminewhether additionalregulatoryactionsarenecessary.

ThisreportdescribestheExpeditedSeismicEvaluationProcess(ESEP)undertakenforSequoyah NuclearPlantUnits1and2.TheintentoftheESEPistoperformaninterimactioninresponsetothe NRCs50.54(f)lettertodemonstrateseismicmarginthroughareviewofasubsetoftheplant equipmentthatcanbereliedupontoprotectthereactorcorefollowingbeyonddesignbasisseismic events.

TheESEPisimplementedusingthemethodologiesintheNRCendorsedguidanceinElectricPower ResearchInstitute(EPRI)3002000704,SeismicEvaluationGuidance:AugmentedApproachforthe ResolutionofFukushimaNearTermTaskForceRecommendation2.1:Seismic[2].

TheobjectiveofthisreportistoprovidesummaryinformationdescribingtheESEPevaluationsand results.ThelevelofdetailprovidedinthereportisintendedtoenabletheNRCtounderstandthe inputsused,theevaluationsperformed,andthedecisionsmadeasaresultoftheinterimevaluations.

ThisESEPreportisforbothSequoyahUnit1andUnit2whichareidentical.Unlessnotedotherwise,all descriptionsinthisreportapplytobothUnit1andUnit2structures,systems,andcomponents.For thisreason,unitdesignationsarenotincludedonequipmentunitidentificationsintheFLEXstrategyor ExpeditedSeismicEquipmentList(ESEL)descriptions.

2.0 BRIEF

SUMMARY

OFTHEFLEXSEISMICIMPLEMENTATIONSTRATEGIES TheSequoyahFLEXstrategiesforReactorCoreCoolingandHeatRemoval,ReactorInventoryControl, andContainmentFunctionaresummarizedbelow.ThissummaryisderivedfromtheSequoyahOverall IntegratedPlan(OIP)inResponsetotheMarch12,2012,CommissionOrderEA12049submittedin February2013[3][4]andisconsistentwiththethirdsixmonthstatusreportissuedtotheNRCin August2014[5].

ForAtPowerConditions CoreCoolingandHeatRemoval ReactorcorecoolingandheatremovalisachievedviasteamreleasefromtheSteamGenerators(SGs) withSGmakeupfromtheTurbineDrivenAuxiliaryFeedwaterPump(TDAFWP)duringFLEXPhase1 withsuctionfromtheCondensateStorageTank(CST)[5].LocalcontrolandoperationoftheSG

SequoyahNuclearPlantESEPReport Page7 AtmosphericReliefValves(ARVs)andtheTDAFWPsystemisavailableandproceduralizedsothat operationfromthemaincontrolroomisnotrequired.

ToprovideanunlimitedsupplyofwaterforcorecoolingduringPhase2,lowpressureFLEXPumpswill bestagedattheIntakePumpStation(IPS)andtakesuctionfromtheintakechannelanddischargeto four,EmergencyRawCoolingWater(ERCW)FLEXconnectionsinsidetheIPS.Theywillbeusedto pressurizetheERCWheaders,whichcanthenbeusedfordirectsupplytotheTDAFWPsuction.

WhentheTDAFWPbecomesunavailableduetoreductioninavailablesteampressure,aportable intermediatepressureFLEXpumpwillbeusedtocontinuetosupplyfeedwatertotheSGs.Suction wouldbefromanERCWFLEXconnection.ThedischargeisroutedbyhosetotheTDAFWPdischarge FLEXconnectionsdownstreamofFlowElement3142.

ReactorInventoryControl ForPhase1,ReactorCoolantSystem(RCS)makeupwillbeprovidedbythecoldlegaccumulators.RCS depressurizationandcooldownwillbeinitiatedassoonaspossibletoreducetheReactorCoolant Pump(RCP)sealleakagerate.

InPhase2,RCSmakeupwillbeprovidedbyrepoweringexistingSafetyInjection(SI)pumpsandusing thepumpstoinjectboratedwaterasneededintotheRCS.TheSIpumpswillberepoweredwitha6.9 kVAFLEXDieselGenerator.TheSIpumpscanbemanuallycontrolledwithhandswitchesonPanelM 6.ThesourceofRCSmakeupwillbetheRefuelingWaterStorageTank(RWST).

LaterinPhase2,whentheRCSisdepressurizedsufficiently,ahighpressureFLEXpumpwillbeusedto injectboratedwaterintotheRCSthroughSIpiping.Thesepumpswouldbealignedwithasuction hosefromRWSTFLEXconnectionsandadischargehoseroutedtoaSIpumpdischargeFLEXheader connection.ThehighpressureFLEXpumpsarefedfromandoperatedfromthe480vControland AuxiliaryBuilding(C&A)VentBoards1A1Aand2A1A.

ContainmentFunction TherearenoPhase1FLEXactionstomaintaincontainmentintegrity.TheprimaryPhase2FLEX strategyforcontainmentintegrityentailsrepoweringonetrainofhydrogenigniters.Phase2may entailrepoweringtheContainmentAirReturnFansinsideofcontainment.

SupportSystems KeyreactorparameterstobemonitoredduringFLEXimplementationaremeasuredandindicatedby instrumentationthatispoweredbythe125VDCvitalbattery.DuringPhase1,thevitalbatteries providepowertoneededinstrumentationthroughthevitalbatteryboards,vitalinvertersandvital instrumentpowerboards.

DuringPhase2,powertovitalinstrumentationwillbemaintainedbysupplying480VACpowertothe vitalbatterychargersthroughnew,fused,FLEXdistributionpanels,whichwillbeconnecteddirectlyto thebatterychargers.480VACpowerwillbesuppliedtothedistributionpanelsbyprestaged,480VAC FLEXdieselgeneratorsthatwillbelocatedontheroofoftheauxiliarybuilding.

DuringtheearlyportionofPhase2,the6.9kVswitchgearand6.9kVShutdownBoardswillbeenergized withaprestaged6.9kVFLEXdieselgeneratorthatwillbelocatedintheadditionaldieselgenerator building.ThiswillallowreenergizingtheSIpumpsforinventorycontrol.

SequoyahNuclearPlantESEPReport Page8 ForShutdownConditions Duringshutdown,bothsafetyfunctions(maintainingcorecoolingandheatremovalandmaintaining RCSinventorycontrol)areaccomplishedbythesameFLEXstrategyandrelyonthesameFLEX equipmentneededfortheatpowercondition.Corecoolingandheatremovalisachievedbycoolant boiloff.InjectionofboratedwatertotheRCSisneededtoreplenishthecoolantlosttoboiling.For shutdownconfigurationswheretheRCSisdepressurizedandopenbutthecavityisnotflooded,gravity feedfromtheRWSTmaybeusedtomaintainRCSinventoryinPhase1.AflowpathfromtheRWSTto theRCSwouldbeestablished.IfgravityfeedisnotsufficienttomakeupcoolanttotheRCS,apre staged,intermediatepressureFLEXpumpwillbeusedtomaintainRCSinventory(inPhase2).

Sufficientflushingflowwillbeneededtopreventboronprecipitation.ConnectionoftheFLEXpump dischargehoseswillbetothesafetyinjectionpipingusingthesameFLEXconnectionsplannedforRCS inventorycontrolunderatpowerconditions.TheFLEXconnectionsareshownin[6]

ForshutdownconfigurationswheretheRCSheadisoffandthecavityisfilled,therewillbesufficient timetomobilizeportableFLEXpumpstoprovideRCSmakeupfromtheBATsoranalternateborated watersource.ThesameFLEXconnectionstothesafetyinjectionsystempipingwillbeusedinthis mode.

Inaccordancewith[7](footnotetoTableD1),someshutdownconfigurationswheretheRCSisclosed orpressurizedsothatinjectionofboratedwatercannotbeaccomplishedareconsideredoutsideof ESEPbecausetheseconfigurationshaveshortdurations.

3.0 EQUIPMENTSELECTIONPROCESSANDESEL TheselectionofequipmentfortheESELfollowedtheguidelinesofEPRI3002000704[2].TheESELfor SequoyahUnits1and2ispresentedinAttachmentA.InformationpresentedinAttachmentAis drawnfrom[8].

3.1 EquipmentSelectionProcessandESEL TheselectionofequipmenttobeincludedontheESELwasbasedoninstalledplantequipment creditedintheFLEXstrategiesduringPhase1,2and3mitigationofaBeyondDesignBasisExternal Event(BDBEE),asoutlinedintheSequoyahOIPinResponsetotheMarch12,2012,CommissionOrder EA12049[3]andisconsistentwiththesecondandthirdsixmonthstatusreportsissuedtotheNRC

[4][5].TheOIPprovidestheSequoyahFLEXmitigationstrategyandservesasthebasisforequipment selectedfortheESEP.

ThescopeofinstalledplantequipmentincludesequipmentrelieduponfortheFLEXstrategiesto sustainthecriticalfunctionsofcorecoolingandcontainmentintegrityconsistentwiththeSequoyah OIP.FLEXrecoveryactionsareexcludedfromtheESEPscopeperEPRI3002000704[2].Theoveralllist ofplannedFLEXmodificationsandthescopeforconsiderationhereinislimitedtothoserequiredto supportcorecooling,reactorcoolantinventoryandsubcriticality,andcontainmentintegrityfunctions.

PortableandprestagedFLEXequipment(notpermanentlyinstalled)areexcludedfromtheESELper EPRI3002000704.

TheESELcomponentselectionfollowedtheEPRIguidanceoutlinedinSection3.2ofEPRI3002000704.

1. Thescopeofcomponentsislimitedtothatrequiredtoaccomplishthecorecoolingand containmentsafetyfunctionsidentifiedinTable32ofEPRI3002000704.The instrumentationmonitoringrequirementsforcorecooling/containmentsafetyfunctions

SequoyahNuclearPlantESEPReport Page9 arelimitedtothoseoutlinedintheEPRI3002000704guidance,andareasubsetofthose outlinedintheSequoyahOIP.

2. ThescopeofcomponentsislimitedtoinstalledplantequipmentandFLEXconnections necessarytoimplementtheSequoyahOIP,asdescribedinSection2.

3. ThescopeofcomponentsassumesthecreditedFLEXconnectionmodificationsare implemented,andarelimitedtothoserequiredtosupportasingleFLEXsuccesspath(i.e.,

eitherPrimaryorBackup/Alternate).

4. ThePrimaryFLEXsuccesspathistobespecified.SelectionoftheBackup/Alternate FLEXsuccesspathmustbejustified.

5. Phase3copingstrategiesareincludedintheESEPscope,whereasrecoverystrategiesare excluded.

6. Structures,systems,andcomponentsexcludedpertheEPRI3002000704guidanceare:

Structures(e.g.containment,reactorbuilding,controlbuilding,auxiliarybuilding,etc.).

Piping,cabling,conduit,HVAC,andtheirsupports.

Manualvalvesandrupturedisks.

PoweroperatedvalvesnotrequiredtochangestateaspartoftheFLEXmitigation strategies.

Nuclearsteamsupplysystemcomponents(e.g.RPVandinternals,reactorcoolant pumpsandseals,etc.).

7. Forcasesinwhichneithertrainwasspecifiedasaprimaryorbackupstrategy,thenonly onetraincomponent(generally'A'train)isincludedintheESEL.

3.1.1 ESELDevelopment TheESELwasdevelopedbyreviewingtheSequoyahNuclearPlantOIP[3][4][5]todeterminethe majorequipmentinvolvedintheFLEXstrategies.Furtherreviewsofplantdrawings(e.g.,Pipingand InstrumentationDiagrams(P&IDs)andElectricalSingleLineDiagrams)wereperformedtoidentifythe boundariesoftheflowpathstobeusedintheFLEXstrategiesandtoidentifyspecificcomponentsin theflowpathsneededtosupportimplementationoftheFLEXstrategies.Boundarieswereestablished atanelectricalormechanicalisolationdevice(e.g.,isolationamplifier,valve,etc.)inbranchcircuits/

branchlinesoffthedefinedstrategyelectricalorfluidflowpath.P&IDsweretheprimaryreference documentsusedtoidentifymechanicalcomponentsandinstrumentation.Theflowpathsusedfor FLEXstrategieswereselectedandspecificcomponentswereidentifiedusingdetailedequipmentand instrumentdrawings,pipingisometrics,electricalschematicsandonelinedrawings,system descriptions,designbasisdocuments,etc.,asnecessary.Hostcomponentswereidentifiedforsub assemblies.

Cabinetsandequipmentcontrolscontainingrelays,contactors,switches,potentiometers,circuit breakersandotherelectricalandinstrumentationthatcouldbeaffectedbyhighfrequencyearthquake motionsandthatimpacttheoperationofequipmentintheESELarerequiredtobeontheESEL.These cabinetsandcomponentswereidentifiedintheESEL.

ForeachparametermonitoredduringtheFLEXimplementation,asingleindicationwasselectedfor inclusionintheESEL.Foreachparameterindication,thecomponentsalongtheflowpathfrom

SequoyahNuclearPlantESEPReport Page10 measurementtoindicationwereincluded,sinceanyfailurealongthepathwouldleadtofailureofthat indication.Componentssuchasflowelementswereconsideredaspartofthepipingandwerenot includedintheESEL.

3.1.2 PowerOperatedValves Page33ofEPRI3002000704[2]notesthatpoweroperatedvalvesnotrequiredtochangestateas partoftheFLEXmitigationstrategiesareexcludedfromtheESEL.Page32alsonotesthatfunctional failuremodesofelectricalandmechanicalportionsoftheinstalledPhase1equipmentshouldbe considered(e.g.AuxiliaryFeedwater(AFW)trips).Toaddressthisconcern,thefollowingguidanceis appliedintheSequoyahESELforfunctionalfailuremodesassociatedwithpoweroperatedvalves:

PoweroperatedvalvesthatremainenergizedduringtheELAPevents(suchasDCpowered valves),wereincludedontheESEL.

PoweroperatedvalvesnotrequiredtochangestateaspartoftheFLEXmitigationstrategies werenotincludedontheESEL.TheseismiceventalsocausestheELAPevent;therefore,the valvesareincapableofspuriousoperationastheywouldbedeenergized.

PoweroperatedvalvesnotrequiredtochangestateaspartoftheFLEXmitigationstrategies duringPhase1,andarereenergizedandoperatedduringsubsequentPhase2and3 strategies,werenotevaluatedforspuriousvalveoperationastheseismiceventthatcaused theELAPhaspassedbeforethevalvesarerepowered.

3.1.3 PullBoxes PullboxesweredeemedunnecessarytobeaddedtotheESELsasthesecomponentsprovide completelypassivelocationsforpullingorinstallingcables.Nobreaksorconnectionsinthecabling wereincludedinpullboxes.Pullboxeswereconsideredpartofconduitandcabling,whichwere excludedinaccordancewithEPRI3002000704[2].

3.1.4 TerminationCabinets Terminationcabinets,includingcabinetsnecessaryforFLEXPhase2andPhase3connections,provide consolidatedlocationsforpermanentlyconnectingmultiplecables.Theterminationcabinetsandthe internalconnectionsprovideacompletelypassivefunction;however,thecabinetsareincludedinthe ESELtoensureindustryknowledgeonpanel/anchoragefailurevulnerabilitiesisaddressed.

3.1.5 CriticalInstrumentationIndicators Criticalindicatorsandrecordersaretypicallyphysicallylocatedonpanels/cabinetsandareincludedas separatecomponents;however,seismicevaluationoftheinstrumentindicationmaybeincludedinthe panel/cabinetseismicevaluation(ruleofthebox).

3.1.6 Phase2and3PipingConnections Item2inSection3.1abovenotesthatthescopeofequipmentintheESELincludesFLEX connectionsnecessarytoimplementtheSequoyahOIP[3][4][5]asdescribedinSection2.Item3in Section3.1alsonotesthatThescopeofcomponentsassumesthecreditedFLEXconnection modificationsareimplemented,andarelimitedtothoserequiredtosupportasingleFLEXsuccesspath (i.e.,eitherPrimaryorBackup/Alternate).

SequoyahNuclearPlantESEPReport Page11 Item6inSection3.1abovegoesontoexplainthatPiping,cabling,conduit,HVAC,andtheirsupports areexcludedfromtheESELscopeinaccordancewithEPRI3002000704[2].

Therefore,pipingandpipesupportsassociatedwithFLEXPhase2andPhase3connectionsare excludedfromthescopeoftheESEPevaluation.However,anyactivevalvesinFLEXPhase2andPhase 3connectionflowpathareincludedintheESEL.

3.2 JustificationforUseofEquipmentThatisNotthePrimaryMeansforFLEXImplementation TheSequoyahNuclearPlantESELisbasedontheprimarymeansofimplementingtheFLEXstrategy.

Therefore,noadditionaljustificationisrequired.

4.0 GROUNDMOTIONRESPONSESPECTRUM(GMRS) 4.1 PlotofGMRSSubmittedbytheLicensee TheSafeShutdownEarthquake(SSE)controlpointelevationisdefinedatthebaseoftheContainment Structures,whichcorrespondstoadepthof64ft.(Elevation641ft.)andisthedeepeststructure foundationelevationcontrolpoint.Table41showstheGMRSaccelerationsforarangeof frequencies.TheGMRSatthecontrolpointelevationisshowninFigure41[9].

Table41: GMRSforSequoyahNuclearPlant Frequency(Hz)

GMRS(g) 100 3.79E01 90 3.83E01 80 3.89E01 70 3.98E01 60 4.18E01 50 4.65E01 40 5.54E01 35 6.14E01 30 6.72E01 25 7.41E01 20 7.59E01 15 7.57E01 12.5 7.49E01 10 7.06E01 9

6.82E01 8

6.53E01 7

6.11E01 6

5.58E01 5

5.00E01

SequoyahNuclearPlantESEPReport Page12 Table41:GMRSforSequoyahNuclearPlant (Continued)

Frequency(Hz)

GMRS(g) 4 4.05E01 3.5 3.78E01 3

3.13E01 2.5 2.50E01 2

2.30E01 1.5 1.92E01 1.25 1.68E01 1

1.42E01 0.9 1.36E01 0.8 1.25E01 0.7 1.14E01 0.6 9.98E02 0.5 8.34E02 0.4 6.67E02 0.35 5.84E02 0.3 5.00E02 0.25 4.17E02 0.2 3.34E02 0.15 2.50E02 0.125 2.08E02 0.1 1.67E02

Figure41:GMRSforSequoyahNuclearPlant

SequoyahNuclearPlantESEPReport Page13 4.2 ComparisontoSSE TheSSEwasdevelopedinaccordancewith10CFRPart100AppendixAthroughanevaluationofthe maximumearthquakepotentialfortheregionsurroundingthesite.Consideringthehistoricseismicity ofthesiteregion,themaximumpotentialearthquakewasdeterminedtobeanintensityVIIIonthe ModifiedMercalliIntensityScaleof1931.TheSSEisdefinedintermsofaPeakGroundAcceleration (PGA)andadesignresponsespectrum.ConsideringasiteintensityofVIII,aPGAof0.18gwas estimated.TobeconsistentwithEPRIReportNos.EPRI3002000704[2]andEPRI1025287[22]thesite licensingbasisearthquakeisusedfortheSSEtoGMRScomparisoninthisreport.Thedesignbasis earthquakewasusedinthepriorTVAsubmittal[9]whichconcludedthatariskanalysiswouldbe performed.However,theapplicationofeitherthedesignbasisorthelicensingbasisSSEcurvetothe priorevaluationwillnotaltertheconclusion.TheSequoyahlicensingbasisSSEisbasedonapeak groundaccelerationof0.18gwithaHousnerspectralshape.Table42showsthespectralacceleration valuesasafunctionoffrequencyforthe5%dampedhorizontalSequoyahlicensingbasisSSE.

Table42:SSEforSequoyahNuclearPlant Frequency (Hz)

SpectralAcceleration (g) 100 0.18 25 0.18 10 0.19 5

0.27 2.5 0.26 1.0 0.14 0.5 0.08

SequoyahNuclearPlantESEPReport Page14

Figure42: GMRStoSSEComparisonforSequoyahNuclearPlant TheSSEandtheGMRSinthelowfrequencyrangeuptoabout2.5Hzareessentiallythesame amplitude.TheGMRSexceedstheSequoyahNuclearPlantSSEbeyondabout2.5Hz.AstheGMRS exceedstheSSEinthe1to10Hzrange,theplantdoesnotscreenoutoftheESEPaccordingtoSection 2.2ofEPRI3002000704[2].ThetwospecialscreeningconsiderationsasdescribedinSection2.2.1of EPRI3002000704,namelya)LowSeismicHazardSiteandb)NarrowBandExceedancesinthe1to10Hz rangedonotapplyforSequoyahNuclearPlantandhenceHighConfidenceofaLowProbabilityof Failure(HCLPF)evaluationsarerequired.

5.0 REVIEWLEVELGROUNDMOTION(RLGM) 5.1 DescriptionofRLGMSelected Section4ofEPRI3002000704[2]presentstwoapproachesfordevelopingtheRLGMtobeusedinthe ESEP:

1. TheRLGMmaybederivedbylinearlyscalingtheSSEbythemaximumratiooftheGMRS/SSE betweenthe1and10Hzrange(nottoexceed2xSSE).InstructureRLGMseismicmotions wouldbederivedusingexistingSSEbasedinstructureresponsespectra(ISRS)withthesame scalefactor.

2. Alternately,licenseeswhohavedevelopedappropriatestructural/soilstructureinteraction (SSI)modelscapableofcalculatingISRSbasedonsiteGMRS/uniformhazardresponsespectrum (UHRS)inputmayopttousetheseISRSinlieuofscaledSSEISRS.

BasedonareviewoftabulateddatainTable41andtheSSEvaluesinTable42,intherangebetween 1and10HzthemaximumratioofGMRStotheSSEiscalculatedtobe:

SFmax=SAGMRS(10HZ)/SASSE10Hz)=0.71g/0.19g=3.7

SequoyahNuclearPlantESEPReport Page15 Sincethecomputedscalefactorisgreaterthan2.0,theRLGMwouldbesetalevelof2xSSE.Thisis showninTable51andFigure51.

Table51: 2xSSEforSequoyahNuclearPlant Frequency (Hz)

SpectralAcceleration (g) 100 0.36 25 0.36 10 0.38 5

0.54 2.5 0.52 1.0 0.28 0.5 0.16

Figure51: 2xSSEforSequoyahNuclearPlant 5.2 MethodtoEstimateInStructureResponseSpectra(ISRS)

AfullscopeSMAwasperformedtosupporttheIPEEEforSequoyahNuclearPlantUnits1and2[11].

TheReviewLevelEarthquake(RLE)isdefinedastheNUREG/CR0098[10]medianspectralshapefor rock,anchoredto0.3gPGA.TheRLEISRSweredefinedatthe84%NonExceedanceProbability(NEP).

Todeterminethe84%NEPresponse,aprobabilisticmethodofgeneratingISRSwasusedwhich accountsfortheuncertaintyinboththegroundmotiondescriptionandinthestructuralandsoil parameters.

Uncertaintiesinthestructuralpropertiesareaccountedforbyrepresentingstructuralnatural frequenciesanddampingratiosasalognormallydistributedrandomvariablewithspecifiedmedian andCoefficientofVariation(COV)values.Atotalofthirty(30)earthquaketimehistories(eachwith 0

0.1 0.2 0.3 0.4 0.5 0.6 0.1 1

10 100 Acceleration(g)

Frequency(Hz)

SQN2xSSEDesignSpectra,5%Damping 2xSSE

SequoyahNuclearPlantESEPReport Page16 threecomponents)weregeneratedsuchthatthespectralordinateswerelognormallydistributedwith aCOVequalto0.25,andthe84%NEPvaluematchestheNUREG/CR0098medianrockshape.

TheresultsoftheIPEEEforSequoyahNuclearPlantUnits1and2weresubmittedtotheNRC[11].It shouldbenotedthattheNRC[12]tookexceptiontotheapproachusedforSequoyahNuclearPlantin thatTennesseeValleyAuthority(TVA)definedtheRLEasbeinginthefreefieldatthetopofthesoil surface,whereastheNRCconcludedtheRLEshouldhavebeendefinedonarock.TVAreviewedthe NRCRequestforAdditionalInformation(RAI)andmadeadjustmentstotheoriginallydefiedHCLPF capacityof0.3g.Theresultsoftheadjustmentsofthefullscopeseismicmarginassessmentwere submittedtotheNRC[13],concludingthatSequoyahNuclearPlantUnits1and2hadaplantlevel HCLPFcapacityof0.23g.SubsequenttoTVA'sdocketedresponse[13]theNRCissuedtheirStaff EvaluationReport(SER)[14].IntheSER,theNRCrecognizedtheTVAHCLPFcapacityvalueof0.23gfor SequoyahNuclearPlant,butalsoacknowledgedalowerHCLPFvalueof0.2gthatwasdevelopedbythe staffconsultant.DuringtheIPEEEadequacyreview,TVAreviewedtheNRCstaffconsultant'sopinion regardingalowerHCLPFcapacityof0.2gforSequoyahNuclearPlantandconcludedthatthetechnical basisdescribedbytheNRCstaffconsultantintheSERistechnicallycorrect.Consequently,TVA decidedthattheassignmentof0.2gHCLPFcapacitywasappropriate.

BecauseofthesignificanteffortexpendedbyTVAtodevelopanupdateddynamicanalysisofthe safetyrelatedstructuresforSequoyahNuclearPlantdescribedaboveandintheIPEEEsubmittal[11],

TVAfeltthismodelprovidedimproveddynamicbehaviorofSequoyahNuclearPlantstructures.

Consequently,forthepurposeofevaluatingseismiccapacityofESEPcomponents,TVAchosetoscale the84thpercentilevaluesbyanincreasescalefactorof1.5(0.3g/0.2g)toachievearesponse equivalenttoa0.3gNUREG/CR0098shapedresponse. Figure52demonstratesthattheuseofa0.3g NUREG/CR0098shaperesponsebounds2xSSEforSequoyahNuclearPlantfrom1to10Hz.

Figure52:NUREG/CR0098(0.3g)versusSequoyahNuclearPlantSSE

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.01 0.1 1

10 100 Acceleration(g)

Frequency(Hz) 2xSSE CR00980.3g SSE(.18g)

SequoyahNuclearPlantESEPReport Page17

6.0 SEISMICMARGINEVALUATIONAPPROACH ItisnecessarytodemonstratethatESELitemshavesufficientseismiccapacitytomeetorexceedthe demandcharacterizedbytheRLGM.TheseismiccapacityischaracterizedasthePGAforwhichthere isaHCLPF.ThePGAisassociatedwithaspecificspectralshape,inthiscasethe5%dampedRLGM spectralshape.TheHCLPFcapacitymustbeequaltoorgreaterthantheRLGMPGA.Thecriteriafor seismiccapacitydeterminationaregiveninSection5ofEPRI3002000704[2].

TherearetwobasicapproachesfordevelopingHCLPFcapacities:

1.

Deterministicapproachusingtheconservativedeterministicfailuremargin(CDFM) methodologyofEPRINP6041SL,AMethodologyforAssessmentofNuclearPower PlantSeismicMargin(Revision1)[15].

2.

ProbabilisticapproachusingthefragilityanalysismethodologyofEPRITR103959, MethodologyforDevelopingSeismicFragilities[16].

6.1 SummaryofMethodologiesUsed SequoyahNuclearPlantcompletedSMAforUnits1and2in1995.TheSMAisdocumentedin[11]that consistedofdevelopmentofaSafeShutdownEquipmentList(SSEL),probabilisticapproachfor determiningseismicdemandbasedon84%NEP,newbuildingmodels,associatedgenerationofISRS, screeningwalkdowns,andHCLPFcapacitycalculations.

ThescreeningwalkdownsusedthescreeningtablesfromChapter2ofEPRINP6041SL[15].The walkdownswereconductedbyengineerstrainedinEPRINP6041SL(theengineersattendedtheEPRI SMAAddOncourseinadditiontotheSQUGWalkdownScreeningandSeismicEvaluationTraining Course),andweredocumentedonScreeningEvaluationWorkSheetsfromEPRINP6041SL.

AnchoragecapacitycalculationsusedtheCDFMcriteriafromEPRINP6041SL.Theseismicdemandis basedonaprobabilisticapproachthatinvolvesthegenerationofanensembleofartificialearthquake (groundmotion)timehistoriesaswellasstructuralandsoilparametersvalues.Theprobabilistic approachofdeterminingseismicdemandisbasedonguidancefromEPRINP6041SL:

"FortheSpecifiedSME,theelasticcomputedresponse(SMEdemand)ofstructuresandcomponents mountedthereonshouldbedefinedatthe84%nonexceedanceprobability(NEP)."

TheresultsoftheprobabilisticapproachfordevelopmentofseismicdemandforSequoyahNuclear plantisdocumentedin[11].

Figure61showsthefitofthe84thpercentileoftheensembleofthe30responsespectra(ofthe30 generatedtimehistories)tothetargetspectralshape(NUREG/CR0098medianrockspectrum).Note thisfigurerepresentstheinputmotionassumingthetargetspectrumisatthetopoffreefieldonthe soilsurface.Figure62showstheadjustedSequoyahNuclearPlantIPEEEHCLPFRLEresponse spectrumadjustedto0.2g,comparedtotheESEPRLGMresponsespectrumusedfortheSequoyah NuclearPlantESEP.Notebothspectraarerockinputmotionsatthebaseofthecontainment structure.ThisdemonstratesthattheESEPRLGMenvelopestheRLGMusedforSMAatallfrequencies byanamplitudefactorof1.5.

SequoyahNuclearPlantESEPReport Page18

Figure61:84thPercentileoftheEnsembleofthe30ResponseSpectra

Figure62:SequoyahNuclearPlantIPEEEadjustedHCLPFvsESEPTargetHCLPF 6.2 HCLPFScreeningProcess ForESEP,thecomponentsarescreenedatRLGM(NUREG/CR0098curve)anchoredat0.3gPGA.The screeningtablesinEPRINP6041SL[15]arebasedongroundpeakspectralaccelerationsof0.8gand 1.2g.ThesebothexceedtheRLGMpeakspectralacceleration.Theanchoragecapacitycalculations

SequoyahNuclearPlantESEPReport Page19 wereonbasedfloorresponsespectradevelopedfortheSequoyahNuclearPlantIPEEEandscaledto theadjustedRLGM.Equipmentforwhichthescreeningcaveatsweremetandforwhichthe anchoragecapacityexceededtheRLGMseismicdemand,canbescreenedoutfromESEPseismic capacitydeterminationbecausetheHCLPFcapacityexceedstheRLGM.

TheUnit1ESELcontains182items.Ofthese,27arevalves,bothpoweroperatedandrelief.In accordancewithTable24ofEPRINP6041SL[15],activevalvesmaybeassignedafunctionalcapacity of0.8gpeakspectralaccelerationwithoutanyreviewotherthanlookingforvalveswithlargeextended operatorsonsmalldiameterpiping,andanchorageisnotafailuremode.Therefore,valvesonthe ESELmaybescreenedoutfromESEPseismiccapacitydetermination,subjecttothecaveatregarding largeextendedoperatorsonsmalldiameterlines.

ThenonvalvecomponentsintheESELaregenerallyscreenedbasedontheSMAmethodology.Ifthe SMAshowedthatthecomponentmettheEPRINP6041SLscreeningcaveatsandtheCDFMcapacity exceededtheRLEdemand,thenthecomponentcanbescreenedoutfromtheESEPcapacity determination.

6.3 SeismicWalkdownApproach 6.3.1 WalkdownApproach WalkdownswereperformedinaccordancewiththecriteriaprovidedinSection5ofEPRI3002000704

[2],whichreferstoEPRINP6041SL[15]fortheSeismicMarginAssessmentprocess.Pages226 through230ofEPRINP6041SLdescribetheseismicwalkdowncriteria,includingthefollowingkey criteria.

TheSRT[SeismicReviewTeam]shouldwalkby100%ofallcomponentswhicharereasonably accessibleandinnonradioactiveorlowradioactiveenvironments.Seismiccapability assessmentofcomponentswhichareinaccessible,inhighradioactiveenvironments,orpossibly withincontaminatedcontainment,willhavetorelymoreonalternatemeanssuchas photographicinspection,morerelianceonseismicreanalysis,andpossibly,smallerinspection teamsandmorehurriedinspections.A100%walkbydoesnotmeancompleteinspectionof eachcomponent,nordoesitmeanrequiringanelectricianorothertechniciantodeenergize andopencabinetsorpanelsfordetailedinspectionofallcomponents.Thiswalkdownisnot intendedtobeaQAorQCrevieworareviewoftheadequacyofthecomponentattheSSElevel.

IftheSRThasareasonablebasisforassumingthatthegroupofcomponentsaresimilarandare similarlyanchored,thenitisonlynecessarytoinspectonecomponentoutofthisgroup.The similaritybasisshouldbedevelopedbeforethewalkdownduringtheseismiccapability preparatorywork(Step3)byreferencetodrawings,calculationsorspecifications.Theone componentoreachtypewhichisselectedshouldbethoroughlyinspectedwhichprobablydoes meandeenergizingandopeningcabinetsorpanelsforthisverylimitedsample.Generally,a sparerepresentativecomponentcanbefoundsoastoenabletheinspectiontobeperformed whiletheplantisinoperation.Atleastfortheonecomponentofeachtypewhichisselected, anchorageshouldbethoroughlyinspected.

Thewalkdownprocedureshouldbeperformedinanadhocmanner.Foreachclassof componentstheSRTshouldlookcloselyatthefirstitemsandcomparethefieldconfigurations withtheconstructiondrawingsand/orspecifications.Ifaonetoonecorrespondenceisfound, thensubsequentitemsdonothavetobeinspectedinasgreatadetail.Ultimatelythe

SequoyahNuclearPlantESEPReport Page20 walkdownbecomesawalkbyofthecomponentclassastheSRTbecomesconfidentthatthe constructionpatternistypical.Thisprocedureforinspectionshouldberepeatedforeach componentclass;although,duringtheactualwalkdowntheSRTmaybeinspectingseveral classesofcomponentsinparallel.Ifseriousexceptionstothedrawingsorquestionable constructionpracticesarefoundthenthesystemorcomponentclassmustbeinspectedincloser detailuntilthesystematicdeficiencyisdefined.

The100%walkbyistolookforoutliers,lackofsimilarity,anchoragewhichisdifferentfrom thatshownondrawingsorprescribedincriteriaforthatcomponent,potentialSI[Seismic Interaction]problems,situationsthatareatoddswiththeteammemberspastexperience,and anyotherareasofseriousseismicconcern.Ifanysuchconcernssurface,thenthelimited samplesizeofonecomponentofeachtypeforthoroughinspectionwillhavetobeincreased.

Theincreaseinsamplesizewhichshouldbeinspectedwilldependuponthenumberofoutliers anddifferentanchorages,etc.,whichareobserved.ItisuptotheSRTtoultimatelyselectthe samplesizesincetheyaretheoneswhoareresponsiblefortheseismicadequacyofallelements whichtheyscreenfromthemarginreview.AppendixDgivesguidanceforsamplingselection.

6.3.2 ApplicationofPreviousWalkdownInformation SeveralESELitemswerepreviouslywalkeddownduringtheSequoyahNuclearPlantUnits1and2 seismicIPEEEprogram.Thosewalkdownresultswerereviewedandthefollowingstepsweretakento confirmthatthepreviouswalkdownconclusionsremainedvalid.

Awalkbywasperformedtoconfirmthattheequipmentmaterialconditionandconfigurationis consistentwiththewalkdownconclusionsandthatnonewsignificantinteractionsrelatedto blockwallsorpipingattachedtotanksexist.

IftheESELitemwasscreenedoutbasedonthepreviouswalkdown,thatscreeningevaluation wasreviewedandreconfirmedfortheESEP.

ExceptforinaccessibleitemsasdescribedbelowinSection7,inallcasesitwasdeterminedthatthe HCLPFcapacitiesestablishedfortheseitemsundertheseismicIPEEEprogramremainedvalid.Thus,all ESELcomponentsthatwerepartoftheIPEEEprogramhaveaHCLPFcapacityof0.3gorgreaterandare thusadequateforESEP[9].

6.3.3 SignificantWalkdownFindings ConsistentwiththeguidancefromEPRINP6041SL[15],nosignificantoutliersandonlyone(1) anchorageconcernwasidentifiedduringtheSequoyahNuclearPlantseismicwalkdowns.The followingfindingswerenotedduringthewalkdowns.

OneanchorforSequoyahUnit2TDAFWPumpControlPanel2L381wasobservedtobesignificantly corroded.Anevaluationwasperformedoftheconfigurationassumingthattheanchorwasinactive.

Theevaluationdeterminedthattheconfiguration(using3of4anchors)satisfieddesignrequirements.

ThecorrodedanchoredisscheduledtobereplacedinupcomingU2R20outage.

Basedonwalkdownresults,HCLPFcapacityevaluationswererecommendedforthefollowingtwelve (12)components,onaboundingbasis:

TurbineDrivenAuxiliaryFeedwaterPump InstrumentRack

SequoyahNuclearPlantESEPReport Page21 RPanels BenchboardMPanels VerticalMandLPanels MainControlRoomCeiling WallMountedPanel BoricAcidStorageTank TDAFWPControlPanel PHMSTransformersandDistributionPanel Valves BlockWalls 6.4 HCLPFCalculationProcess ESELitemsnotincludedinthepreviousIPEEEevaluationsatSequoyahwereevaluatedusingthe criteriainEPRINP6041[7].Thoseevaluationsincludedthefollowingsteps:

Performingseismiccapabilitywalkdownsforequipmentnotincludedinpreviousseismic walkdowns(SQUG,IPEEE,orNTTF2.3)toevaluatetheequipmentinstalledplantconditions PerformingscreeningevaluationsusingthescreeningtablesinEPRINP6041asdescribedin Section6.2and PerformingHCLPFcalculationsconsideringvariousfailuremodesthatincludebothstructural failuremodes(e.g.anchorage,loadpathetc.)andfunctionalfailuremodes.

AllHCLPFcalculationswereperformedusingtheCDFMmethodologyandaredocumentedinaTVA Calculation:CDQ9992014000140SQNExpeditedSeismicEvaluationProcess(ESEP)HCLPFCapacity Calculation[17].

6.5 FunctionalEvaluationsofRelays ESEPconsiderscabinetsandequipmentcontrolscontainingrelays,contactors,switches,circuit breakersandotherelectricalandinstrumentationcomponentsthatcouldbeaffectedbyhigh frequencyearthquakemotionsandthatimpacttheoperationofequipmentintheESEL.

AfullscopeSMAwasperformedtosupporttheIPEEEforSequoyahNuclearPlantUnits1and2as summarizedintheIPEEEsubmittal[11].AslightlymodifiedversionoftheEPRINP6041SL[15]

recommendedapproachwasimplementedfortheSequoyahNuclearPlantIPEEEinordertoincrease efficiency.Allrelayswerescreenedoutby:(1)groundrulesandassumptions;(2)comparisonofdesign qualificationtestspectrum(orgenericequipmentruggednessspectra)withSeismicMargin Earthquake(SME)incabinetresponsespectrum;or(3)analysisshowingthatrelaychatterdoesnot disablesafeshutdownequipmentwithoutthepossibilityofrecovery.Inallcases,equipmentactuation wasdeterminedtonotaffectthesafeshutdowncapabilityoftheequipmentintheSSEL.Low ruggednessrelayswerescreenedoutonlyiftheeffectsofchattercouldberesetbyoperatoraction.

Allbuttwolowruggednessrelaysfellintothiscategory.Theremainingtworelayswerefoundtonot beusedinsafeshutdownequipmentatSequoyahNuclearPlant.Theprincipalconclusionfromthe

SequoyahNuclearPlantESEPReport Page22 IPEEErelayevaluationwasthatsafeshutdownsystemswillnotbeadverselyaffectedbyrelay malfunctionduringorafteranSME.

FortheSequoyahNuclearPlantESEPanalysis,anevaluationwasperformedtoidentifycomponents thatare(1)neededforFLEXimplementation,(2)notontheSequoyahIPEEESSEL,and(3)thathavethe potentialforrelaychatterissues.TheonlycasesidentifiedaretheFCV117andFCV118steam isolationvalvesthatcanisolatethesteamsupplytotheTDAFWpump.Intheeventofasteamline break,bothofthesevalvescanreceiveaclosesignalifhightemperatureisdetectedintheTDAFW pumproom.However,becausethesevalvesaremotoroperatedvalves(MOVs),withaLossofOffsite Power(LOOP)thevalveswillnotisolateevenwithaspuriousclosesignal.Therefore,thesevalvesdo notpresentaproblemforsuccessfulFLEXimplementation.Nootherrelaychattercaseswere identified.NoseismiccapacitytodemandrelayevaluationswerenecessaryforESEP.

6.6 TabulatedESELHCLPFValues(IncludingKeyFailureModes)

TabulatedESELHCLPFvaluesareprovidedinAttachmentB.Thefollowingnotesapplytothe informationinthetables.

ItemspreviouslyincludedintheseismicIPEEEprogramsarenotlisted.Walkbyverificationsre confirmedtheHCLPFcapacitiesfromtheIPEEE,andtheIPEEE0.3gRLEHCLPFcapacityexceeds theRLGM[18].

HCLPFcapacityevaluationswereperformedforthenonIPEEEitemsontheESEL,addressing bothstructural/anchorageandfunctionalfailuremodes.TheHCLPFcapacityofeachitemis listedinthetables,withassociatedgoverningfailuremode.

Ruggeditemsnotspecificallyevaluatedareconservativelyassigneda0.50gHCLPFcapacity basedontheEPRIscreeningtablesorbyengineeringjudgment.

NewprestagedandpermanentlyinstalledFLEXitemsarenotlisted.TVAdesigncriteriaSQN DCV48.0[19]requiresthatnewFLEXitemshaveHCLPFcapacityexceedingtheRLGM.

AllESEPcomponentshaveaHCLPFcapacitygreaterthantheRLGMforthefrequencyrangeof1to 10Hz.

7.0 INACCESSIBLEITEMS 7.1 IdentificationofESELItemInaccessibleforWalkdowns Therearefour(4)valvesandseven(7)instrumentracksthatcouldnotbewalkeddownsincetheyare intheUnit1ReactorBuilding(inaccessiblearea).ThesecomponentsUnit2counterpartswere walkeddownduringtherecentUnit2outage.TheUnit2componentsweredeterminedtobe acceptable.ItisexpectedthatthesameconclusioncanbemadefortheUnit1components.The followingisalistoftheUnit1componentslocatedintheReactorBuildingthatwerenotwalkeddown:

1FCV63118ColdlegAccumulatorIsolationValve#1 1FVC6367ColdlegAccumulatorIsolationValve#4 1FCV6380ColdlegAccumulatorIsolationValve#3 1FCV6398ColdlegAccumulatorIsolationValve#2 InstrumentRack1L182locatedinFanRoom2

SequoyahNuclearPlantESEPReport Page23 InstrumentRack1L183locatedinFanRoom1 InstrumentRack1L179 InstrumentRack1L185 InstrumentRack1L704 InstrumentRack1L706 InstrumentRack1L194 Alsotherearetwo(2)panelsthatcouldnotbewalkeddownintheUnit1AuxiliaryBuildingbecause thecomponentsareinaContaminatedandRadiationArea.Theyare:

InstrumentRack1L196 InstrumentRack1L216 Inaddition,awalkbyinsideUnit1containmentwasnotpossible.

7.2 PlannedWalkdown/EvaluationSchedule/CloseOut ThefollowingUnit1componentswillbewalkeddowninupcomingUnit1outage:

FCV63118ColdLegAccumulatorIsolationValve#1 FVC6367ColdLegAccumulatorIsolationValve#4 FCV6380ColdLegAccumulatorIsolationValve#3 FCV6398ColdLegAccumulatorIsolationValve#2 InstrumentRack1L182locatedinFanRoom2 InstrumentRack1L183locatedinFanRoom1 InstrumentRack1L179 InstrumentRack1L185 InstrumentRack1L704 InstrumentRack1L706 InstrumentRack1L194 InstrumentRack1L196 InstrumentRack1L216 Inaddition,asperformedinsidetheUnit2containment,awalkbywillbeconductedtoverifythat HCLPFcapacityofatleast0.3gismaintainedforIPEEEitemsontheESEL.Itisexpectedthatthesame conclusionswillbemadefortheUnit1componentsthatwerecompletedforthecounterpart componentsinUnit2.

SequoyahNuclearPlantESEPReport Page24 8.0 ESEPCONCLUSIONSANDRESULTS 8.1 SupportingInformation SequoyahNuclearPlantUnits1and2haveperformedtheESEPasaninterimactioninresponsetothe NRCs50.54(f)letter[1].ItwasperformedusingthemethodologiesintheNRCendorsedguidancein EPRI3002000704[2].

TheESEPprovidesanimportantdemonstrationofseismicmarginandexpeditesplantsafety enhancementsthroughevaluationsandpotentialneartermmodificationsofplantequipmentthatcan bereliedupontoprotectthereactorcorefollowingbeyonddesignbasisseismicevents.

TheESEPispartoftheoverallSequoyahNuclearPlantUnits1and2inresponsetotheNRCs50.54(f) letter.OnMarch12,2014,NEIsubmittedtotheNRCresultsofastudy[21]ofseismiccoredamage riskestimatesbasedonupdatedseismichazardinformationasitappliestooperatingnuclearreactors intheCentralandEasternUnitedStates(CEUS).Thestudyconcludedthatsitespecificseismic hazardsshowthattherehasnotbeenanoverallincreaseinseismicriskforthefleetofU.S.plants basedonthereevaluatedseismichazards.Assuch,thecurrentseismicdesignofoperatingreactors continuestoprovideasafetymargintowithstandpotentialearthquakesexceedingtheseismicdesign basis.

TheNRCsMay9,2014NTTF2.1ScreeningandPrioritizationletter[20]concludedthatthefleetwide seismicriskestimatesareconsistentwiththeapproachandresultsusedintheGl199safety/risk assessment.TheletteralsostatedthatAsaresult,thestaffhasconfirmedthattheconclusions reachedinGl199safety/riskassessmentremainvalidandthattheplantscancontinuetooperate whileadditionalevaluationsareconducted.

AnassessmentofthechangeinseismicriskforSequoyahNuclearPlantUnits1and2wasincludedin thefleetriskevaluationsubmittedintheMarch12,2014NEIletter[21];therefore,theconclusionsin theNRCsMay9letteralsoapplytoSequoyahNuclearPlantUnits1and2.

Inaddition,theMarch12,2014NEIletterprovidedanattachedPerspectivesontheSeismicCapacity ofOperatingPlants,which(1)assessedanumberofqualitativereasonswhythedesignofSSCs inherentlycontainmarginbeyondtheirdesignlevel,(2)discussedindustrialseismicexperience databasesofperformanceofindustryfacilitycomponentssimilartonuclearSSCs,and(3)discussed earthquakeexperienceatoperatingplants.

Thefleetofcurrentlyoperatingnuclearpowerplantswasdesignedusingconservativepractices,such thattheplantshavesignificantmargintowithstandlargegroundmotionssafely.Thishasbeenborne outforthoseplantsthathaveactuallyexperiencedsignificantearthquakes.Theseismicdesignprocess hasinherent(andintentional)conservatismswhichresultinsignificantseismicmarginswithinSSCs.

Theseconservatismsarereflectedinseveralkeyaspectsoftheseismicdesignprocess,including:

Safetyfactorsappliedindesigncalculations DampingvaluesusedindynamicanalysisofSSCs BoundingsynthetictimehistoriesforISRScalculations BroadeningcriteriaforISRS ResponsespectraenvelopingcriteriatypicallyusedinSSCanalysisandtestingapplications

SequoyahNuclearPlantESEPReport Page25 Responsespectrabasedfrequencydomainanalysisratherthanexplicittimehistorybasedtime domainanalysis Boundingrequirementsincodesandstandards Useofminimumstrengthrequirementsofstructuralcomponents(concreteandsteel)

Boundingtestingrequirements Ductilebehavioroftheprimarymaterials(thatis,notcreditingtheadditionalcapacityof materialssuchassteelandreinforcedconcretebeyondtheessentiallyelasticrange,etc.)

ThesedesignpracticescombinetoresultinmarginssuchthattheSSCswillcontinuetofulfilltheir functionsatgroundmotionswellabovetheSSE.

TheintentoftheESEPistoperformaninterimactioninresponsetotheNRCs50.54(f)letterto demonstrateseismicmarginthroughareviewofasubsetoftheplantequipmentthatcanberelied upontoprotectthereactorcorefollowingbeyonddesignbasisseismicevents.Inordertocomplete theESEPinanexpeditedamountoftime,theRLGMusedfortheESEPevaluationisascaledversionof theplantsSSEratherthantheactualGMRS.Tomorefullycharacterizetheriskimpactsoftheseismic groundmotionrepresentedbytheGMRSonaplantspecificbasis,amoredetailedseismicrisk assessment(SPRAorriskbasedSMA)istobeperformedinaccordancewithEPRI1025287[22].As identifiedintheSequoyahNuclearPlantUnits1and2SeismicHazardandGMRSsubmittal[9],

SequoyahNuclearPlantUnits1and2screensinforariskevaluation.Thecompleteriskevaluationwill morecompletelycharacterizetheprobabilisticseismicgroundmotioninputintotheplant,theplant responsetothatprobabilisticseismicgroundmotioninput,andtheresultingplantrisk characterization.SequoyahNuclearPlantUnits1and2willcompletethatevaluationinaccordance withthescheduleidentifiedinNEIsletterdatedApril9,2013[23]andendorsedbytheNRCintheir May7,2013letter[24].

8.2 IdentificationofPlannedModifications Onemodificationwasidentifiedinunit2,torepairacorrodedanchorobservedforTDAFWpump ControlPanel2L381.

8.3 ModificationImplementationSchedule PlantmodificationswillbeperformedinaccordancewiththescheduleidentifiedinNEIletterdated April9,2013[23],whichstatesthatplantmodificationsnotrequiringaplannedrefuelingoutagewill becompletedbyDecember2016andmodificationsrequiringarefuelingoutagewillbecompleted withintwoplannedrefuelingoutagesafterDecember31,2014.

TheplantmodificationidentifiedinSection8.2requiresarefuelingoutagethatwillbeperformedin theupcomingunit2refuelingoutage(U2R20)andwillbecompletedbytheendofDecember2015.

SequoyahNuclearPlantESEPReport Page26 8.4 SummaryofRegulatoryCommitments ThefollowingactionswillbeperformedasaresultoftheESEP.

Table81:SummaryofRegulatoryCommitments Action Equipment ID Equipment Description ActionDescription CompletionDate 1

NA N/A Performseismicwalkdowns,generate HCLPFcalculations,anddesignand implementanynecessary modificationsforUnit1inaccessible itemslistedinSection7.1 Nolaterthantheend ofthesecond plannedUnit1 refuelingoutage afterDecember31, 2014 2

2L381 TDAFP Control Panel Modifyanchoragetoreplace corrodedanchorsuchthatHCLPF

>RLGM Nolaterthantheend ofU2R20Refueling Outage,December 31,2015 3

N/A N/A SubmitalettertoNRCsummarizing theHCLPFresultsofItem1and confirmingimplementationofthe plantmodificationsassociatedwith Item2 Within60days followingcompletion ofESEPactivities, includingItems1 through2

SequoyahNuclearPlantESEPReport Page27

9.0 REFERENCES

1.

NRC(ELeedsandMJohnson)LettertoAllPowerReactorLicenseesetal.,Requestfor InformationPursuanttoTitle10oftheCodeofFederalRegulations50.54(f)Regarding Recommendations2.1,2.3and9.3oftheNearTermTaskForceReviewofInsightsfromthe FukushimaDaiIchiAccident,March12,2012.

2.

EPRI3002000704,SeismicEvaluationGuidance,AugmentedApproachfortheResolutionof FukushimaNearTermTaskForceRecommendation2.1:Seismic,May2013.

3.

TVALettertoU.S.NRC,TennesseeValleyAuthority-OverallIntegratedPlaninResponseto March12,2012,CommissionOrderModifyingLicenseswithRegardtoRequirementsfor MitigationStrategiesforBeyondDesignBasisExternalEvents(OrderNumberEA12049),

February28,2013.

4.

TVALettertoU.S.NRC,SecondSixMonthStatusReportandRevisedOverallIntegratedPlanin ResponsetotheMarch12,2012,CommissionOrderModifyingLicenseswithRegardto RequirementsforMitigationStrategiesforBeyondDesignBasisExternalEvents(OrderNumber EA12049)forSequoyahNuclearPlant,February28,2014.

5.

TVALettertoU.S.NRC,ThirdSixMonthStatusReportinResponsetotheMarch12,2012, CommissionOrderModifyingLicenseswithRegardtoRequirementsforMitigationStrategies forBeyondDesignBasisExternalEvents(OrderNumberEA12049)forBrownsFerryNuclear Plant(TACNos.MF0864andMF0865),August28,2014.

6.

TVADrawing147W8111FLEX,FlowDiagramSafetyInjectionSystem,Revision74(Modified forFLEX).

7.

NEI1206,DiverseandFlexibleCopingStrategies(FLEX)ImplementationGuide,Revision0, August2012.

8.

AREVANPDocument519217523005,ESEPExpeditedSeismicEquipmentList(ESEL)-

SequoyahNuclearPlant.

9.

TVALettertoU.S.NRC,letternumberCNL14038,TennesseeValleyAuthoritysSeismic HazardandScreeningReport(CEUSSites),responsetoNRCRequestforInformationPursuant to10CFR50.54(f)regardingRecommendation2.1oftheNearTermTaskForceReviewof InsightsfromtheFukushimaDaiichiAccident,March31,2014 10.

U.S.NRCNUREG/CR0098,DevelopmentofCriteriaforSeismicReviewofSelectedNuclear PowerPlants,May1978.

11.

TVALetterfromR.H.ShelltoU.S.NRC,SequoyahNuclearPlant(SQN)-GenericLetterGL88 20,SupplementNo.4,IndividualPlantExaminationofExternalEvents(IPEEE)forSevere AccidentVulnerabilities-10CFR50.54(f),June29,1995.

12.

NRCLettertoTVA,SequoyahNuclearPlant,Units1and2-RequestforAdditionalInformation onIndividualPlantExaminationofExternalEvents(TACNos.M86374andM86375),August2, 2000.

13.

LetterfromPedroSalastoNRC,SequoyahNuclearPlantUnits1and2-ResponsetoRequest forAdditionalInformationoftheIndividualPlantExaminationofExternalEvents(IPEEE)(TAC Nos.M83674andM83675),December5,2000.

SequoyahNuclearPlantESEPReport Page28 14.

LetterfromNRCtoJ.A.Scalice,SequoyahNuclearPlant,Units1and2-ReviewofSequoyah IndividualPlantExaminationofExternalEventsSubmittal(TACNos.M83764andM83675),

February21,2001.

15.

EPRINP6041SL,MethodologyforAssessmentofNuclearPowerPlantSeismicMargin, Revision1,August1991.

16.

EPRITR103959,MethodologyforDevelopingSeismicFragilities,July1994.

17.

TVACalculationCDQ9992014000140,SQNExpeditedSeismicEvaluationProcess(ESEP)

HCLPFCapacityCalculation.

18.

TVAlettertoU.S.NRC,LetternumberCNL14013,HighlightsofImprovementstothe SequoyahNuclearPlantIPEEESeismicAnalysisResultsandSupplementalResponsetoNRC RequestforInformationPursuanttoTitle10oftheCodeofFederalRegulations50.54(f) regardingtheSequoyahNuclearPlantUnit1SeismicWalkdownResultsofRecommendations 2.3oftheNearTermTaskForceReviewofInsightsfromtheFukushimaDaiichiAccident, January31,2014.

19.

TVADesignCriteria,SQNDCV48.0,Revision4,FLEXResponseSystem.

20.

NRC(E.Leeds)LettertoAllPowerReactorLicenseesetal.,ScreeningandPrioritizationResults RegardingInformationPursuanttoTitle10oftheCodeofFederalRegulations50.54(F)

RegardingSeismicHazardReEvaluationsforRecommendation2.1oftheNearTermTaskForce ReviewofInsightsFromtheFukushimaDaiIchiAccident,May9,2014.

21.

NuclearEnergyInstitute(NEI),A.Pietrangelo,LettertoD.SkeenoftheUSNRC,SeismicCore DamageRiskEstimatesUsingtheUpdatedSeismicHazardsfortheOperatingNuclearPlantsin theCentralandEasternUnitedStates,March12,2014.

22.

EPRI1025287,SeismicEvaluationGuidance:Screening,PrioritizationandImplementation Details(SPID)fortheResolutionofFukushimaNearTermTaskForceRecommendation2.1:

Seismic.ElectricPowerResearchInstitute,February2013.

23.

NuclearEnergyInstitute(NEI),A.Pietrangelo,LettertoD.SkeenoftheUSNRC,ProposedPath ForwardforNTTFRecommendation2.1:SeismicReevaluations,April9,2013.NRCAdams AccessionNo.ML13101A379.

24.

NRC(ELeeds)LettertoNEI(JPollock),ElectricPowerResearchInstituteFinalDraftReport xxxxx,SeismicEvaluationGuidance:AugmentedApproachfortheResolutionofFukushima NearTermTaskForceRecommendation2.1:Seismic,asanAcceptableAlternativetothe March12,2012,InformationRequestforSeismicReevaluations,May7,2013.

SequoyahNuclearPlantESEPReport PageA1 ATTACHMENTA-SEQUOYAHNUCLEARPLANTESEL

SequoyahNuclearPlantESEPReport PageA2 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 1

VLV1512 SteamGenerator#3MainSteamSafety Valve Operational Operational

2 VLV1517 SteamGenerator#2MainSteamSafety Valve Operational Operational

3 VLV1522 SteamGenerator#1MainSteamSafety Valve Operational Operational

4 VLV1527 SteamGenerator#4MainSteamSafety Valve Operational Operational

5 PCV15 SteamGenerator#1ARV(SGPORV)

Operational Operational FailclosedonlossofTrainAessentialair 6

PCV112 SteamGenerator#2ARV(SGPORV)

Operational Operational FailclosedonlossofTrainBessentialair 7

PCV123 SteamGenerator#3ARV(SGPORV)

Operational Operational FailclosedonlossofTrainAessentialair 8

PCV130 SteamGenerator#4ARV(SGPORV)

Operational Operational FailclosedonlossofTrainBessentialair 9

PCV15 SteamGenerator#1ARV(SGPORV)Hand wheel Operational Operational LocalcontrolofsteamgeneratorPORV duringELAP 10 AirBottles SteamGenerator#2ARV(SGPORV)Local ControlStation Operational Operational EmergencycontrolstationperEA12 FLEXcompressedaircylinders 11 AirBottles SteamGenerator#3ARV(SGPORV)Local ControlStation Operational Operational EmergencycontrolstationperEA12 FLEXcompressedaircylinders 12 PCV130 SteamGenerator#4ARV(SGPORV)Hand wheel Operational Operational LocalcontrolofsteamgeneratorPORV duringELAP

SequoyahNuclearPlantESEPReport PageA3 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 13 L501 PCV112LocalControlStation Operational Operational EmergencycontrolstationperEA12 14 L502 PCV123LocalControlStation Operational Operational EmergencycontrolstationperEA12 15 PMP3142 TurbineDrivenAFWPump Standby Operating AutomaticstartonLOOP 16 FCV151 TDAFWPumpTripandThrottleValve Closed Open Normalpowersupplyisfrom125VVital BatteryBoardIII 17 FCV152 TDAFWPumpGovernorValve Closed Open FailsopenonlossofDCcontrolpower 18 XS4657 AFWTASBackupControlTransferSwitch Operational Operational ThesecomponentsareontheESELifmanual operationofTDAFWisimplemented 19 HS151B TDAFWPumpTripandThrottleValve Handswitch Operational Operational

20 SI4656B TDAFWPumpSpeedIndicator Operational Operational

21 FIC4657 TDAFWPumpMasterSpeedController Operational Operational

22 L381 TDAFWPumpControlPanel Operational Operational

23 PI3138 TDAFWPumpDischargePressure Indicator Operational Operational

24 L215 AFWFlowMonitoringPanel Operational Operational Portabledeltapressgaugecanbeusedfor localmonitoringofAFWflow

SequoyahNuclearPlantESEPReport PageA4 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 25 FT3147 AFWFlowtoSteamGenerator#3Flow Transmitter Operational Operational

26 FT3155 AFWFlowtoSteamGenerator#2Flow Transmitter Operational Operational

27 FT3163 AFWFlowtoSteamGenerator#1Flow Transmitter Operational Operational

28 FT3170 AFWFlowtoSteamGenerator#4Flow Transmitter Operational Operational

29 FI3147B AFWFlowtoSteamGenerator#3Flow Indication Operational Operational

30 FI3155B AFWFlowtoSteamGenerator#2Flow Indication Operational Operational

31 FI3163B AFWFlowtoSteamGenerator#1Flow Indication Operational Operational

32 FI3170B AFWFlowtoSteamGenerator#4Flow Indication Operational Operational

33 L341 AFWFlowtoSteamGenerator#3Flow TransmitterRack Operational Operational

34 L217 AFWFlowtoSteamGenerator#2Flow TransmitterRack Operational Operational

35 L216 AFWFlowtoSteamGenerator#1Flow TransmitterRack Operational Operational

36 L703 AFWFlowtoSteamGenerator#4Flow IndicationRack Operational Operational

SequoyahNuclearPlantESEPReport PageA5 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 37 LCV3172 SteamGenerator#3LevelControlValve Closed Open FailsopenonlossofAXpowerorcontrolair.

Backupairsupplybottlesavailable.Manual operationwithhandwheelisavailable.

38 LCV3173 SteamGenerator#2LevelControlValve Closed Open FailsopenonlossofACpowerorcontrolair.

Backupairsupplybottleavailable.Manual operationwithhandwheelisavailable.

39 LCV3174 SteamGenerator#1LevelControlValve Closed Open FailsopenonlossofACpowerorcontrolair.

Backupairsupplybottlesavailable.Manual operationwithhandwheelisavailable.

40 LCV3175 SteamGenerator#4LevelControlValve Closed Open FailsopenonlossofACpowerorcontrolair.

Backupairsupplybottlesavailable.Manual operationwithhandwheelisavailable.

41 XS3172 SteamGenerator#3LevelControlValve TransferSwitch Operational Operational

42 XS3173 SteamGenerator#2LevelControlValve TransferSwitch Operational Operational

43 XS3174 SteamGenerator#1LevelControlValve TransferSwitch Operational Operational

44 XS3175 SteamGenerator#4LevelControlValve TransferSwitch Operational Operational

45 L11A SteamGeneratorLevelControlPanel Operational Operational

46 L11B SteamGeneratorLevelControlPanel Operational Operational

47 HS3172B SteamGenerator#3LevelControlValve HandSwitch Operational Operational

SequoyahNuclearPlantESEPReport PageA6 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 48 HS3173B SteamGenerator#2LevelControlValve HandSwitch Operational Operational

49 HS3174B SteamGenerator#1LevelControlValve HandSwitch Operational Operational

50 HS3175B SteamGenerator#4LevelControlValve HandSwitch Operational Operational

51 L661 SteamGenerator#2LevelControlValve FLEXBackupAirStation Operational Operational

52 L662 SteamGenerator#1LevelControlValve FLEXBackupAirStation Operational Operational

53 L663 SteamGenerator#3LevelControlValve FLEXBackupAirStation Operational Operational

54 L664 SteamGenerator#4LevelControlValve FLEXBackupAirStation Operational Operational

55 LT343 SteamGenerator#1WideRangeLevel Transmitter Operational Operational

56 1LT356 SteamGenerator#2WideRangeLevel Transmitter Operational Operational

57 2LT356 SteamGenerator#2WideRangeLevel Transmitter Operational Operational Unit2SG3LevelTransmitteronRackL182 Unit1SG3LevelTransmitteronRackL706 58 LT398 SteamGenerator#3WideRangeLevel Transmitter Operational Operational

59 LT3111 SteamGenerator#4WideRangeLevel Transmitter Operational Operational

60 L183 SteamGeneratorLevelTransmitterRack Operational Operational

SequoyahNuclearPlantESEPReport PageA7 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 61 L706 SteamGeneratorLevelTransmitterRack (Unit1)

Operational Operational

62 L704 SteamGeneratorLevelTransmitterRack Operational Operational

63 L185 SteamGeneratorLevelTransmitterRack Operational Operational

64 L182 SteamGeneratorLevelTransmitterRack (Unit2)

Operational Operational

65 LI343 SteamGenerator#1WideRangeLevel Indicator Operational Operational

66 LI356 SteamGenerator#2WideRangeLevel Indicator Operational Operational

67 LI398 SteamGenerator#3WideRangeLevel Indicator Operational Operational

68 LI3111 SteamGenerator#4WideRangeLevel Indicator Operational Operational

69 PT12A SteamGenerator#1DischargePressure Transmitter Operational Operational 120VVIPBIRack3 70 PT19A SteamGenerator#2DischargePressure Transmitter Operational Operational 120VVIPBIRack3 71 PT120A SteamGenerator#3DischargePressure Transmitter Operational Operational 120VVIPBIRack4 72 PT127A SteamGenerator#4DischargePressure Transmitter Operational Operational 120VVIPBIRack4 73 L194 SteamGeneratorDischargePressure TransmitterRack Operational Operational

SequoyahNuclearPlantESEPReport PageA8 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 74 L196 SteamGeneratorDischargePressure TransmitterRack Operational Operational

75 PI12D SteamGenerator#1DischargePressure Indicator Operational Operational ChannelAinput 76 PI19D SteamGenerator#2DischargePressure Indicator Operational Operational ChannelAinput 77 PI120D SteamGenerator#3DischargePressure Indication Operational Operational ChannelAinput 78 PI127D SteamGenerator#4DischargePressure Indication Operational Operational ChannelAinput 79 1TNK0020229 Unit1CondensateStorageTank Operational Operational DCN23191willseismicallyqualifyCSTto2x SSEHCLPF 80 2TNK0020232 Unit2CondensateStorageTank Operational Operational DCN23191willseismicallyqualifyCSTto2x SSEHCLPF 81 FCV3179A ERCWHeaderBAFWSupplyValve Closed Open SwitchovertoERCWheader480VMOV Board1(2)B2B/11Eorhandwheel 82 FCV3179B ERCWHeaderBAFWSupplyValve Closed Open SwitchovertoERCWheader480VMOV Board1(2)B2B/11Borhandwheel 83 FCV3136A ERCWHeaderAAFWSupplyValve Closed Open SwitchovertoERCWheader480VMOV Board1(2)A2A/2Eorhandwheel 84 FCV3136B ERCWHeaderAAFWSupplyValve Closed Open SwitchovertoERCWheader480VMOV Board1(2)A2A/2Borhandwheel 85 FCV63118 ColdLegAccumulator#1IsolationValve Open Closed

86 FCV6398 ColdLegAccumulator#2IsolationValve Open Closed

SequoyahNuclearPlantESEPReport PageA9 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 87 FCV6380 ColdLegAccumulator#3IsolationValve Open Closed

88 FCV6367 ColdLegAccumulator#4IsolationValve Open Closed

89 1PMP6310A SafetyInjectionPump Standby Operational

90 2PMP6310A SafetyInjectionPump Standby Operational

91 HS6310A SafetyInjectionPumpHandSwitch Operational Operational

92 M6 PanelM6 Operational Operational

93 1TNK0620239 BoricAcidTank(BAT)A Available Available

94 2TNK0620239 BoricAcidTank(BAT)B Available Available

95 0TNK0620243 BoricAcidTank(BAT)C Available Available

96 HEX0740015 RHRHeatExchanger1A Intact Intact RWSTgravityfeedpath 97 TNK063044 RWST Operational Operational

98 PCV0680340A RCSPressurizerPowerReliefValve Operational Operational 125VDCVitalBatteryBoardI 99 HS68340AA PressurizerPORVHandSwitch Operational Operational

SequoyahNuclearPlantESEPReport PageA10 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 100 PDT3044 ContainmentPressureDifferential Transmitter Operational Operational

101 PDI3044 ContainmentPressureDifferential Indicator Operational Operational

102 1FAN0300038 Unit1ContainmentAirReturnFanA Standby Operational Poweredby480VSDB1A1 103 2FAN0300038 Unit2ContainmentAirReturnFanA Standby Operational Poweredby480VSDB2A1 104 HS3038A ContainmentAirReturnFanAHand Switch Operational Operational

105 M9 PanelM9 Operational Operational

106 1XFA2681AA PHMSXfrm1A Operational Operational Powersupplytohydrogenigniters 107 2XFA2682AA PHMSXfrm2A Operational Operational Powersupplytohydrogenigniters 108 1PNL268YA 120VACPHMSDistributionPanel1A Operational Operational Powersupplytohydrogenigniters 109 2PNL268YC 120VACPHMSDistributionPanel2A Operational Operational Powersupplytohydrogenigniters 110 TNK01838 1AA7DayOilSupplyTank Available Available UsetosupplydieselpoweredFLEX equipment 111 TNK01840 1BB7DayOilSupplyTank Available Available UsetosupplydieselpoweredFLEX equipment 112 TNK01839 2AA7DayOilSupplyTank Available Available UsetosupplydieselpoweredFLEX equipment

SequoyahNuclearPlantESEPReport PageA11 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 113 TNK01841 2BB7DayOilSupplyTank Available Available UsetosupplydieselpoweredFLEX equipment 114 1BDB201DJ 480VShutdownBoardA1A Operational Operational

115 1BDB201DK 480VShutdownBoardA2A Operational Operational

116 1BDB201DL 480VShutdownBoardB1B Operational Operational

117 1BDB201DM 480VShutdownBoardB2B Operational Operational

118 2BDB201DN 480VShutdownBoardA1A Operational Operational

119 2BDB201DO 480VShutdownBoardA2A Operational Operational

120 2BDB201DP 480VShutdownBoardB1B Operational Operational

121 2BDB201DQ 480VShutdownBoardB2B Operational Operational

122 1BDC201GG 480VReactorMOVBoard1A1A Operational Operational Powertosafetyinjectionaccumulator isolationMOVs 123 1BDC201GJ 480VReactorMOVBoard1B1B Operational Operational Powertosafetyinjectionaccumulator isolationMOVs 124 2BDC201GL 480VReactorMOVBoard2A1A Operational Operational Powertosafetyinjectionaccumulator isolationMOVs 125 2BDC201GN 480VReactorMOVBoard2B1B Operational Operational Powertosafetyinjectionaccumulator isolationMOVs

SequoyahNuclearPlantESEPReport PageA12 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 126 1BDC201JE 480VC&AVentBoard1A1A Operational Operational PowertohighpressureFLEXpump Repoweredby6.9kVFLEXdieselgenerator 127 1BDC201JF 480VC&AVentBoard1A2A Operational Operational PowertointermediatepressureFLEXpump Repoweredby6.9kVFLEXdieselgenerator 128 2BDC201JJ 480VC&AVentBoard2A1A Operational Operational PowertohighpressureFLEXpump Repoweredby6.9kVFLEXdieselgenerator 129 2BDC201JK 480VC&AVentBoard2A2A Operational Operational PowertointermediatepressureFLEXPump Repoweredby6.9kVFLEXdieselgenerator 130 BDG250KE 125VDCVitalBatteryBoardI Operational Operational

131 BDG250KF 125VDCVitalBatteryBoardII Operational Operational

132 BDG250KG 125VDCVitalBatteryBoardIII Operational Operational

133 BDG250KH 125VDCVitalBatteryBoardIV Operational Operational

134 1BDE250NCD 120VACVitalInstrumentPowerBoard1I Operational Operational

135 1BDE250NEE 120VACVitalInstrumentPowerBoard1II Operational Operational

136 1BDE250NGF 120VACVitalInstrumentPowerBoard1 III Operational Operational

137 1BDE250NJG 120VACVitalInstrumentPowerBoard1 IV Operational Operational

138 2BDE250NDD 120VACVitalInstrumentPowerBoard2I Operational Operational

SequoyahNuclearPlantESEPReport PageA13 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 139 2BDE250NFE 120VACVitalInstrumentPowerBoard2II Operational Operational

140 2BDE250NHF 120VACVitalInstrumentPowerBoard2 III Operational Operational

141 2BDE250NKG 120VACVitalInstrumentPowerBoard2 IV Operational Operational

142 0BATB250QV 125VDCVitalBatteryI Operational Operational

143 0BATB250QW 125VDCVitalBatteryII Operational Operational

144 0BATB250QX 125VDCVitalBatteryIII Operational Operational

145 0BATB250QY 125VDCVitalBatteryIV Operational Operational

146 0CHGB250QE 125VDCVitalBatteryChargerI Operational Operational

147 0CHGB250QG 125VDCVitalBatteryChargerII Operational Operational

148 0CHGB250QH 125VDCVitalBatteryChargerIII Operational Operational

149 0CHGB250QJ 125VDCVitalBatteryChargerIV Operational Operational

150 1INVB250QL 120VACVitalInverter1I Operational Operational

151 1INVB250QN 120VACVitalInverter1II Operational Operational

SequoyahNuclearPlantESEPReport PageA14 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 152 1INVB250QR 120VACVitalInverter1III Operational Operational

153 1INVB250QT 120VACVitalInverter1IV Operational Operational

154 2INVB250QM 120VACVitalInverter2I Operational Operational

155 2INVB250QP 120VACVitalInverter2II Operational Operational

156 2INVB250QS 120VACVitalInverter2III Operational Operational

157 2INVB250QU 120VACVitalInverter2IV Operational Operational

158 1XE925001 N31NeutronDetector Operational Operational Unit1NISChannel1 159 1XM925001A N31NeutronSourceRangeAmplifier Operational Operational

160 1XM925001B N31NeutronSourceRangeOptical Isolator Operational Operational

161 1XI925 N31SignalProcessorAppR Operational Operational

162 1XX925001 N31SourceRangeIndicator Operational Operational

163 1XI925001A N31BSourceRangeIndicator Operational Operational

164 2XE925002 N32NeutronDetector Operational Operational Unit2NISChannel2

SequoyahNuclearPlantESEPReport PageA15 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 165 2XM925002A N32NeutronSourceRangeAmplifier Operational Operational

166 2XE925002B N32NeutronSourceRangeOptical Isolator Operational Operational

167 2XI925 N32SignalProcessorAppR Operational Operational

168 2XX925002 N32SourceRangeIndicator Operational Operational

169 2XI925002B N32BSourceRangeIndicator Operational Operational

170 L10 InstrumentRack Operational Operational

171 M4 InstrumentPanel Operational Operational

172 M13 InstrumentPanel Operational Operational

173 PT6869 RCSLoopWRPressureTransmitterLoop1 Operational Operational

174 PT6866 RCSLoopWRPressureTransmitterLoop3 Operational Operational

175 PI6869 RCSLoopWRPressureIndicationLoop1 Operational Operational

176 PI6866A RCSLoopWRPressureIndicationLoop3 Operational Operational

177 L388 Instrumentpanel Operational Operational

SequoyahNuclearPlantESEPReport PageA16 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 178 L340 InstrumentPanel Operational Operational

179 L649 InstrumentPanel Operational Operational

180 R4 InstrumentRack Operational Operational

181 R5 InstrumentRack Operational Operational

182 TE6818 ColdLegWRTemperatureElementLoop1 Operational Operational

183 TE6841 ColdLegWRTemperatureElementLoop2 Operational Operational

184 TE6860 ColdLegWRTemperatureElementLoop3 Operational Operational

185 TE6883 ColdLegWRTemperatureElementLoop4 Operational Operational

186 TI6818 ColdLegWRTemperatureIndicationLoop 1

Operational Operational

187 TI6841 ColdLegWRTemperatureIndicationLoop 2

Operational Operational

188 TI6860 ColdLegWRTemperatureIndicationLoop 3

Operational Operational

189 TI6883 ColdLegWRTemperatureIndicationLoop 4

Operational Operational

190 TE681 HotLegWRTemperatureElementLoop1 Operational Operational

SequoyahNuclearPlantESEPReport PageA17 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 191 TE6824 HotLegWRTemperatureElementLoop2 Operational Operational

192 TE6843 HotLegWRTemperatureElementLoop3 Operational Operational

193 TE6865 HotLegWRTemperatureElementLoop4 Operational Operational

194 TI681 HotLegWRTemperatureIndicationLoop 1

Operational Operational

195 TI6824 HotLegWRTemperatureIndicationLoop 2

Operational Operational

196 TI6843 HotLegWRTemperatureIndicationLoop 3

Operational Operational

197 TI6865 HotLegWRTemperatureIndicationLoop 4

Operational Operational

198 M5 InstrumentPanel Operational Operational

199 R2 InstrumentRack Operational Operational

200 R6 InstrumentRack Operational Operational

201 LT68325C RCSPressurizerLevelTransmitter Operational Operational

202 LI68325C RCSPressurizerLevelIndication Operational Operational

203 L179 InstrumentationPanel Operational Operational

SequoyahNuclearPlantESEPReport PageA18 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 204 0DG360000A 480VFLEXDieselGenerator Standby Operational

205 0DG360003A 6.9kVFLEXDieselGenerator Standby Operational

206 1PNLA082TU DieselGenerator1BBControlPanel Standby Operational

207 1PNLA082TT DieselGeneratorG1AAControlPanel Standby Operational

208 2PNLA082TV DieselGenerator2AAControlPanel Standby Operational

209 2PNLA082TW DieselGenerator2BBControlPanel Standby Operational

210 0BD3600003A FLEXDieselGenerator3ASwitchgear Standby Operational

211 0BKR360 0003A/1/A2 FLEXDG3ASwitchgearBreakerA2 Standby Operational DCN23197 212 0TANK360113 6900V3MWFLEXDGFuelOilStorage Tank3A Standby Operational DCN23197 213 0SW360 0003A/1 6900V3MWFLEXDieselGEN3AFused DisconnectSwitch Standby Operational DCN23197 214 0XFMR360 3A/1 6900V480V3MWFLEXDieselGEN3A20 KVADryTypeTransformer Standby Operational DCN23197 215 0XFMR360 3A/2 480V120/240V3MWFLEXDieselGEN3A 5KVADryTypeTransformer Standby Operational DCN23197 216 0DPL360 0003A/1 480VoltDistributionPanelwith100A MainCircuitBreaker Standby Operational DCN23197

SequoyahNuclearPlantESEPReport PageA19 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 217 0DPL360 0003A/2 120/240VACPanelboard Standby Operational DCN23197 218 0FU1360 0103A PrimaryCntrlFuseforFuelOilPumpA Starter Standby Operational DCN23197 219 0FU1360 0103B SecondaryCntrlFuseforFuelOilPumpA Starter Standby Operational DCN23197 220 0FU1360 0103C PrimaryCntrlFuseforFuelOilPumpA Starter Standby Operational DCN23197 221 0HS360103C FuelOilTransferPmpAEmerStopSW Standby Operational DCN23197 222 0PMP360103 FuelOilSystemTransferPump3A Standby Operational DCN23197 223 0RES360003A 3MWFLEXDieselGeneratorANeutral GroundingResistor Standby Operational DCN23197 224 0STR3600103 3MWFLEXDieselGeneratorFuelOil TransferPumpStarter Standby Operational DCN23197 225 0LS3600103 3MWFLEXDieselGeneratorFuelOilFloat Switch(FillPumpControl)

Standby Operational DCN23197 226 0XSW082 0001A TransferSwitch1A Standby Operational DCN23197 227 0XSW082 0002A TransferSwitch2A Standby Operational DCN23197 228 0XSW082 0003B TransferSwitch2B Standby Operational DCN23197 229 0XSW082 0004B TransferSwitch1B Standby Operational DCN23197

SequoyahNuclearPlantESEPReport PageA20 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 230 1BDA202CM A

6.9kVShutdownBoard1AA Operational Operational

231 2BDA202COA 6.9kVShutdownBoard2AA Operational Operational

232 1BDA202CN 6.9kVShutdownBoard1BB Operational Operational

233 2BDA202CP 6.9kVShutdownBoard2BB Operational Operational

234 1OXF202DL 480VShutdownTransformer1B1 Operational Operational Listedas1XFA2020317inIPEEE 235 1OXF202DM 480VShutdownTransformer1B2 Operational Operational Listedas1XFA2020319inIPEEE 236 1OXF202DJ 480VShutdownTransformer1A1 Operational Operational Listedas1XFA2020313inIPEEE 237 1OXF202DK 480VShutdownTransformer1A2 Operational Operational Listedas1XFA2020315inIPEEE 238 2OXF202DN 480VShutdownTransformer2A1 Operational Operational Listedas2XFA2020315inIPEEE 239 2OXF202DO 480VShutdownTransformer2A2 Operational Operational Listedas2XFA2020313inIPEEE 240 2OXF202DP 480VShutdownTransformer2B1 Operational Operational Listedas2XFA2020319inIPEEE 241 2OXF202DQ 480VShutdownTransformer2B2 Operational Operational Listedas2XFA2020317inIPEEE 242 1PMP360IP01 U1IntermediatePressureFLEXPump Standby Operational Poweredby480VC&AVentBD1A2,DCN 23193

SequoyahNuclearPlantESEPReport PageA21 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 243 2PMP360IP01 U2IntermediatePressureFLEXPump Standby Operational Poweredby480VC&AVentBD2A2,DCN 23193 244 1PMP360HPCS U1HighPressureFLEXPump Standby Operational Poweredby480VC&AVentBD1A1,DCN 23193 245 2PMP360HPCS U2HighPressureFLEXPump Standby Operational Poweredby480VC&AVentBD2A1,DCN 23193 246 SQN1IGN268 0142A Unit1TrainAHydrogenIgniter Standby Operational

247 SQN1IGN268 0130A Unit1TrainAHydrogenIgniter Standby Operational

248 SQN1IGN268 0125A Unit1TrainAHydrogenIgniter Standby Operational

249 SQN1IGN268 0123A Unit1TrainAHydrogenIgniter Standby Operational

250 SQN1IGN268 0116A Unit1TrainAHydrogenIgniter Standby Operational

251 SQN1IGN268 0128A Unit1TrainAHydrogenIgniter Standby Operational

252 SQN1IGN268 0129A Unit1TrainAHydrogenIgniter Standby Operational

253 SQN1IGN268 0114A Unit1TrainAHydrogenIgniter Standby Operational

254 SQN1IGN268 0133A Unit1TrainAHydrogenIgniter Standby Operational

255 SQN1IGN268 0102A Unit1TrainAHydrogenIgniter Standby Operational

SequoyahNuclearPlantESEPReport PageA22 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 256 SQN1IGN268 0115A Unit1TrainAHydrogenIgniter Standby Operational

257 SQN1IGN268 0132A Unit1TrainAHydrogenIgniter Standby Operational

258 SQN1IGN268 0108A Unit1TrainAHydrogenIgniter Standby Operational

259 SQN1IGN268 0127A Unit1TrainAHydrogenIgniter Standby Operational

269 SQN1IGN268 0155A Unit1TrainAHydrogenIgniter Standby Operational

270 SQN1IGN268 0136A Unit1TrainAHydrogenIgniter Standby Operational

271 SQN1IGN268 0131A Unit1TrainAHydrogenIgniter Standby Operational

272 SQN1IGN268 0121A Unit1TrainAHydrogenIgniter Standby Operational

273 SQN1IGN268 0122A Unit1TrainAHydrogenIgniter Standby Operational

274 SQN1IGN268 0135A Unit1TrainAHydrogenIgniter Standby Operational

275 SQN1IGN268 0159A Unit1TrainAHydrogenIgniter Standby Operational

276 SQN1IGN268 0126A Unit1TrainAHydrogenIgniter Standby Operational

277 SQN1IGN268 0107A Unit1TrainAHydrogenIgniter Standby Operational

SequoyahNuclearPlantESEPReport PageA23 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 278 SQN2IGN268 0226A Unit2TrainAHydrogenIgniter Standby Operational

279 SQN2IGN268 0235A Unit2TrainAHydrogenIgniter Standby Operational

280 SQN2IGN268 0202A Unit2TrainAHydrogenIgniter Standby Operational

281 SQN2IGN268 0223A Unit2TrainAHydrogenIgniter Standby Operational

282 SQN2IGN268 0222A Unit2TrainAHydrogenIgniter Standby Operational

283 SQN2IGN268 0231A Unit2TrainAHydrogenIgniter Standby Operational

284 SQN2IGN268 0206A Unit2TrainAHydrogenIgniter Standby Operational

285 SQN2IGN268 0205A Unit2TrainAHydrogenIgniter Standby Operational

286 SQN2IGN268 0234A Unit2TrainAHydrogenIgniter Standby Operational

287 SQN2IGN268 0214A Unit2TrainAHydrogenIgniter Standby Operational

288 SQN2IGN268 0208A Unit2TrainAHydrogenIgniter Standby Operational

289 SQN2IGN268 0259A Unit2TrainAHydrogenIgniter Standby Operational

290 SQN2IGN268 0250A Unit2TrainAHydrogenIgniter Standby Operational

SequoyahNuclearPlantESEPReport PageA24 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 291 SQN2IGN268 0232A Unit2TrainAHydrogenIgniter Standby Operational

292 SQN2IGN268 0201A Unit2TrainAHydrogenIgniter Standby Operational

293 SQN2IGN268 0230A Unit2TrainAHydrogenIgniter Standby Operational

294 SQN2IGN268 0249A Unit2TrainAHydrogenIgniter Standby Operational

295 SQN2IGN268 0254A Unit2TrainAHydrogenIgniter Standby Operational

296 SQN2IGN268 0224A Unit2TrainAHydrogenIgniter Standby Operational

297 SQN2IGN268 0233A Unit2TrainAHydrogenIgniter Standby Operational

298 SQN2IGN268 0255A Unit2TrainAHydrogenIgniter Standby Operational

299 SQN2IGN268 0207A Unit2TrainAHydrogenIgniter Standby Operational

300 SQN2IGN268 0236A Unit2TrainAHydrogenIgniter Standby Operational

301 SQN2IGN268 0221A Unit2TrainAHydrogenIgniter Standby Operational

302 SQN2IGN268 0213A Unit2TrainAHydrogenIgniter Standby Operational

303 SQN2IGN268 0228A Unit2TrainAHydrogenIgniter Standby Operational

SequoyahNuclearPlantESEPReport PageA25 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 304 SQN2IGN268 0216A Unit2TrainAHydrogenIgniter Standby Operational

305 SQN2IGN268 0229A Unit2TrainAHydrogenIgniter Standby Operational

306 SQN2IGN268 0242A Unit2TrainAHydrogenIgniter Standby Operational

307 SQN2IGN268 0227A Unit2TrainAHydrogenIgniter Standby Operational

308 SQN2IGN268 0215A Unit2TrainAHydrogenIgniter Standby Operational

309 SQN2IGN268 0225A Unit2TrainAHydrogenIgniter Standby Operational

310 SQN1IGN268 0105A Unit1TrainAHydrogenIgniter Standby Operational

311 SQN1IGN268 0154A Unit1TrainAHydrogenIgniter Standby Operational

312 SQN1IGN268 0106A Unit1TrainAHydrogenIgniter Standby Operational

313 SQN1IGN268 0113A Unit1TrainAHydrogenIgniter Standby Operational

314 SQN1IGN268 0149A Unit1TrainAHydrogenIgniter Standby Operational

315 SQN1IGN268 0101A Unit1TrainAHydrogenIgniter Standby Operational

316 SQN1IGN268 0150A Unit1TrainAHydrogenIgniter Standby Operational

SequoyahNuclearPlantESEPReport PageA26 TABLEA1:ExpeditedSeismicEquipmentList(ESEL)forSequoyahNuclearPlant(Continued)

ESEL Item Number Equipment OperatingState Notes/Comments ID Description Normal State Desired State 317 SQN1IGN268 0124A Unit1TrainAHydrogenIgniter Standby Operational

318 SQN1IGN268 0134A Unit1TrainAHydrogenIgniter Standby Operational

SequoyahNuclearPlantESEPReport PageB1 ATTACHMENTB-ESEPHCLPFVALUESANDFAILUREMODESTABULATIONFOR SEQUOYAHNUCLEARPLANT

SequoyahNuclearPlantESEPReport PageB2 TABLEB1:ESEP HCLPF Values and Failure Modes for Sequoyah Nuclear Plant Equipment ID EquipmentDescription Equipment Class Building Floor Elevation FailureMode HCLPF Capacity (g) 1PCV15 2PCV15 SteamGenerator#1ARV Handwheel 7

ACB 734 Screen 0.50 1PCV130 2PCV130 SteamGenerator#4ARV Handwheel 7

ACB 734 Screen 0.50 1L501 2L501 PCV112LocalControl Station 18 ACB 714 Functional 0.62 1L502 2L502 PCV123LocalControl Station 18 ACB 714 Functional 0.62 1PMP3142 2PMP3142 TDAFWPump 5

ACB 669 Functional 1.01 1FCV151 2FCV151 TDAFWPumpTripand ThrottleValve 8A ACB 669 Screen 0.50 1FCV152 2FCV152 TDAFWPumpGovernor Valve 7

ACB 669 Functional 1.01 1XS4657 2XS4657 AFWTASBackupControl TransferServiceWater 14 ACB 669 Functional 0.88 1HS151B 2HS151B TDAFWPumpTripand ThrottleValveHS 20 ACB 669 Functional 0.88 1L381 2L381 TDAFWPumpControl Panel 20 ACB 669 Functional 0.85 1L215 2L215 AFWFlowMonitoring Panel 18 ACB 669 Functional 0.62 1L341 2L341 AFWFlowtoSteam Generator#3FTRack 18 ACB 714 Functional 0.62 1L217 2L217 AFWFlowtoSteam Generator#2FTRack 18 ACB 714 Functional 0.62 1L216 2L216 AFWFlowtoSteam Generator#1FTRack 18 ACB 690 Functional 0.62 1L703 2L703 AFWFlowtoSteam Generator#4Flow IndicationRack 18 ACB 690 Functional 0.62 1L11A 2L11A SteamGeneratorLevel ControlPanel 20 ACB 734 Functional 0.75 1L11B 2L11B SteamGeneratorLevel ControlPanel 20 ACB 734 Functional 0.75

SequoyahNuclearPlantESEPReport PageB3 TABLEB1:ESEP HCLPF Values and Failure Modes for Sequoyah Nuclear Plant (Continued)

Equipment ID EquipmentDescription Equipment Class Building Floor Elevation FailureMode HCLPF Capacity (g) 1L183 2L183 SteamGeneratorLevel TransmitterRack 18 RB 697 Functional 0.62 1L706 2L182 SteamGeneratorLevel TransmitterRack 18 RB 697 Functional 0.62 1L704 2L704 SteamGeneratorLevel TransmitterRack 18 RB 697 Functional 0.62 1L185 2L185 SteamGeneratorLevel TransmitterRack 18 RB 697 Functional 0.62 1L194 2L194 SteamGenerator DischargePressure TransmitterRack 18 ACB 690 Functional 0.62 1L196 2L196 SteamGenerator DischargePressure TransmitterRack 18 ACB 690 Functional 0.62 1TNK002 0229 Unit1Condensate StorageTank 21 YARD 705 DCN23191

>2xSSE 2TNK002 0232 Unit2Condensate StorageTank 21 YARD 705 DCN23191

>2xSSE 1FCV63118 2FCV63118 ColdLegAccumulator#1 IsolationValve 8a RB 693 Screen 0.50 1FCV6398 2FCV6398 ColdLegAccumulator#2 IsolationValve 8a RB 693 Screen 0.50 1FCV6380 2FCV6380 ColdLegAccumulator#3 IsolationValve 8a RB 693 Screen 0.50 1FCV6367 2FCV6367 ColdLegAccumulator#4 IsolationValve 8a RB 693 Screen 0.50 1M6 2M6 MCRBenchboardM6 20 ACB 732 MainControl RoomCeiling 0.425 1TNK062 0239 BoricAcidTank(BAT)A 21 ACB 690 Overturning Moment 0.78 2TNK062 0239 BoricAcidTank(BAT)B 21 ACB 690 Overturning Moment 0.78 0TNK062 0243 BoricAcidTank(BAT)C 21 ACB 690 Overturning Moment 0.78 1M9 2M9 MCRVerticalPanelM9 20 ACB 732 MainControl RoomCeiling 0.425

SequoyahNuclearPlantESEPReport PageB4 TABLEB1:ESEP HCLPF Values and Failure Modes for Sequoyah Nuclear Plant (Continued)

Equipment ID EquipmentDescription Equipment Class Building Floor Elevation FailureMode HCLPF Capacity (g)

SQN1IGN 268 (MANY)

HydrogenIgniters 0

RB SCV Screen 0.50 1XFA268 1AA PHMSXfrm1A 4

ACB 759 Functional 0.36 2XFA268 2AA PHMSXfrm2A 4

ACB 759 Functional 0.36 1PNL268 YA 120VACPHMS DistributionPanel1A 14 ACB 759 Functional 0.36 2PNL268YC 120VACPHMS DistributionPanel2A 14 ACB 759 Functional 0.36 TNK01838 1AA7DayOilSupply Tank 21 DGB 719 Screen 0.50 TNK01840 1BB7DayOilSupply Tank 21 DGB 719 Screen 0.50 TNK01839 2AA7DayOilSupply Tank 21 DGB 719 Screen 0.50 TNK01841 2BB7DayOilSupply Tank 21 DGB 719 Screen 0.50 1XE925001 N31NeutronDetector 18 RB 697 Screen 0.50 1XM92 5001A N31NeutronSource RangeAmplifier 20 ACB 734 Screen 0.50 1XM92 5001B N31NeutronSource RangeOpticalIsolation 20 ACB 734 Screen 0.50 2XE925002 N32NeutronDetector 18 RB 697 Screen 0.50 2XM92 5002A N32NeutronSource RangeAmplifier 20 ACB 714 Screen 0.50

SequoyahNuclearPlantESEPReport PageB5 TABLEB1:ESEP HCLPF Values and Failure Modes for Sequoyah Nuclear Plant (Continued)

Equipment ID EquipmentDescription Equipment Class Building Floor Elevation FailureMode HCLPF Capacity (g) 2XM92 5002B N32NeutronSource RangeOpticalIsolation 20 ACB 714 Screen 0.50 1L10 2L10 RemoteControlPanel L10 20 ACB 734 Functional 0.425 1M4 2M4 MCRBenchboardM4 20 ACB 732 MainControl RoomCeiling 0.425 1M13 2M13 MCRVerticalPanelM13 20 ACB 732 MainControl RoomCeiling 0.425 1L388 2L388 RCSLoopWRPTLoop1 InstrumentRack 28 ACB 690 Functional 0.62 1L340 2L340 RCSLoopWRPTLoop3 InstrumentRack 28 ACB 690 Functional 0.62 1R4 2R4 AIRPanelR4 20 ACB 685 Functional 0.64 1R5 2R5 AIRPanelR5 20 ACB 685 Functional 0.64 1TE6818 2TE6818 ColdLegWR TemperatureElement Loop1 19 RB 693 Screen 0.50 1TE6841 2TE6841 ColdLegWR TemperatureElement Loop2 19 RB 693 Screen 0.50 1TE6860 2TE6860 ColdLegWR TemperatureElement Loop3 19 RB 693 Screen 0.50 1TE6883 2TE6883 ColdLegWR TemperatureElement Loop4 19 RB 693 Screen 0.50 1TE681 2TE681 HotLegWRTemperature ElementLoop1 19 RB 679 Screen 0.50 1TE6824 2TE6824 HotLegWRTemperature ElementLoop2 19 RB 679 Screen 0.50 1TE6843 2TE6843 HotLegWRTemperature ElementLoop3 19 RB 679 Screen 0.50 1TE6865 2TE6865 HotLegWRTemperature ElementLoop4 19 RB 679 Screen 0.50 1M5 2M5 MCRBenchboardM5 20 ACB 732 MainControl RoomCeiling 0.425

SequoyahNuclearPlantESEPReport PageB6 TABLEB1:ESEP HCLPF Values and Failure Modes for Sequoyah Nuclear Plant (Continued)

Equipment ID EquipmentDescription Equipment Class Building Floor Elevation FailureMode HCLPF Capacity (g) 1R2 2R2 AIRPanelR2 20 ACB 685 Functional 0.64 1R6 2R6 AIRPanelR6 20 ACB 685 Functional 0.64 1L179 2L179 RCSPressurizerLevel TransmitterInstrument Rack 18 RB

Functional 0.62 2XM92 5002B N32NeutronSource RangeOpticalIso.

20 ACB 714 Screen 0.50 1M2 CabinetM2 20 ACB 732 MainControl RoomCeiling 0.425 1FCV3 136A 2FCV3 136A ERCWHeaderAAFW SupplyValve 8a ACB 669 Screen 0.50 1FCV3136B 2FCV3136B ERCWHeaderAAFW SupplyValve 8a ACB 669 Screen 0.50 1FCV3 179A 2FCV3 179A ERCWHeaderBAFW SupplyValve 8a ACB 669 Screen 0.50 1FCV3179B 2FCV3179B ERCWHeaderBAFW SupplyValve 8a ACB 669 Screen 0.50

E2-1 of 1 ENCLOSURE 2 LIST OF COMMITMENTS

1. Perform seismic walkdowns, generate HCLPF calculations, and design and implement any necessary modification for the following Unit 1 inaccessible items no later than the end of the second planned Unit 1 refueling outage after December 31, 2014:

a. FCV 63-118 - Cold Leg Accumulator Isolation Valve #1

b. FCV 63-067 - Cold Leg Accumulator Isolation Valve #4

c. FCV 63-080 - Cold Leg Accumulator Isolation Valve #3

d. FCV 63-098 - Cold Leg Accumulator Isolation Valve #2

e. Instrument Rack 1 - L - 182 located in Fan Room 2

f.

Instrument Rack 1 - L - 183 located in Fan Room 1

g. Instrument Rack 1 - L - 179

h. Instrument Rack 1 - L - 185

i.

Instrument Rack 1 - L - 704

j.

Instrument Rack 1 - L - 706

k. Instrument Rack 1 - L - 194

l.

Instrument Rack 1 - L - 196

m. Instrument Rack 1 - L - 216

2. Modify TDAFP Control Panel 2-L-381 anchorage to replace the corroded anchor such that HCLPH > RLGM no later than the end of the U2 Cycle 20 refueling outage.

3. Submit a letter to NRC summarizing the HCLPF results of Commitment 1 and confirming implementation of the plant modifications associated with Commitment 2 within 60 days following completion of ESEP activities.