ML21140A299

Response to Request for Additional Information for Proposed License Amendment Request to Add an Analytical Methodology to the Core Operating Limits Report for a Large Break Loss of Coolant Accident

ML21140A299
Person / Time
Site:	Millstone
Issue date:	05/20/2021
From:	Mark D. Sartain Dominion Energy Nuclear Connecticut
To:	Document Control Desk, Office of Nuclear Reactor Regulation
Shared Package
ML21140A298	List: ML21140A299
References
21-154
Download: ML21140A299 (17)

Text

PROPRIETARY INFORMATION-WITHHOLD UNDER10CFR2.390 Dominion Energy Nuclear Connecticut, Inc.

5000 Dominion Boulevard, GlenAllen, VA23060 DominionEnergy,com

@QQ May20,2021 U.S.

Nuclear Regulatory Commission Serial No.21-154 Attention:

Document ControlDesk NRA/SS RO Washington, DC 20555 Docket No.

50-423 License No.

NPF-49 I

MILLSTONE POWER STATION UNIT 3

RESPONSE

TO REQUESTFOR ADDITIONAL INFORMATION FORPROPOSED I

LICENSEAMENDMENT REQUEST TOADDANANALYTICALMETHODOLOGY TO THE COREOPERATING LIMITS REPORT FORA LARGEBREAKLOSSOF COOLANTACCIDENT t

Byletter datedNovember 5,2020(Agencywide Documents Access andManagement System(ADAMS)

Accession No.ML20310A324),

Dominion Energy Nuclear Connecticut, Inc.

(DENC),

submitted a license amendment request (LAR) totheNuclear Regulatory Commission (NRC) forMillstone PowerStation,Unit No.3 (MPS3).Theproposed amendment would revise Technical Specification (TS)6.9.1.6.b byadding WCAP-16996-P-A,Revision 1,"Realistic LOCAEvaluation Methodology Applied totheFull Spectrum ofBreakSizes (Full Spectrum LOCAMethodology),"

tothe list of methodologies approved forreference intheCoreOperating Limits Report (COLR) for MPS3.

Theaddedreference identifies theanalytical methods usedtodetermine thecore operating limits forthelarge j

breaklossofcoolant accident (LBLOCA) eventdescribed inthe MPS3 FinalSafety Analysis Report.

Inan emaildatedMarch31,2021,theNRCissued a draft request for additional information (RAI) related totheproposed LAR. OnApril 13,2021,theNRC staff conducted aconference call withDENCstaff toclarify therequest.

Inanemail dated E

April 15,2021,theNRCtransmitted thefinal version oftheRAI(ADAMS Accession No. ML21105A115).

DENCagreed torespond totheRAlwithin 45daysofissuance, orno later thanMay31,2021.

Theproprietary information inAttachment 3issupported byanaffidavit (Attachment 2) signed byWestinghouse Electric CompanyLLC.,theowneroftheinformation.

The attached affidavit setsforth thebasis onwhichtheinformation maybewithheld from public disclosure bytheNRCandaddresses, with specificity, theconsiderations listed in paragraph (b)(4) of10CFR2.390.Accordingly, itisrespectfully requested thatthe information thatisproprietary toWestinghouse bewithheld frompublic disclosure in accordance with 10CFR2.390.

3i1 Attachment 3contains proprietary information thatisbeingwithheld frompublic disclosure under10CFR2.390.

Uponseparation ofAttachment 3,thisletter isdecontrolled.

g I

s

Serial No.21-154 Docket No.50-423 Page2of3 Correspondence with respect tothecopyright orproprietary aspects oftheitems listed

above, or thesupporting Westinghouse affidavit, shouldreference CAW-21-5177 (Attachment 2)andshould beaddressed toCamille T.zozula,

Manager, Regulatory Compliance Corporate Licensing, Westinghouse Electric Company,1000 Westinghouse

Drive, Cranberry Township, Pennsylvania 16066.

DENC'sresponse to theRAIisprovided inAttachment 1 (non-proprietary) and Attachment 3 (proprietary).

Westinghouse's affidavit forwithholding proprietary information isprovidedin Attachment 2.

Ifyouhaveanyquestions orrequire additional information, please contact Shayan Sinha at(804) 273-4687.

Sincerely,

/

y j, MarkD.Sartain VicePresident

- Nuclear Engineering

&Fleet Support COMMONWEALTH OFVIRGINIA))

COUNTYOFHENRICO

)

Theforegoing document wasacknowledged before me,inandforthe County and Commonwealth aforesaid, today byMr.MarkD.Sartain, whoisVicePresident

- Nuclear Engineering andFleet Support ofDominion Energy Nuclear Connecticut, Inc.Hehasaffirmed before me thatheisduly authorized toexecute andfile theforegoing document inbehalf ofthat

company, and thatthe statements inthedocument aretrue tothebestofhisknowledge andbelief.

Acknowledged before methis204dayof

, 2021.

MyCommission Expires:

CRAIGDSLY Notary Public Commonwealth ofVirginia Reg.#7518653 Notaryublic MyCommission Expires December 31,2D Attachments:

1.Response toRequest forAdditional Information Regarding LARtoAddan Analytical Methodology totheCOLRforaLBLOCA(Non-Proprietary) 2.Westinghouse Affidavit forWithholding Proprietary Information (Non-Proprietary) 1 3.Response toRequest forAdditional Information Regarding LARtoAddan Analytical Methodology totheCOLRforaLBLOCA(Proprietary)

Commitments madeinthis letter:

None l

Serial No.21-154 Docket No.50-423 Page3of3 cc:

U.S. NuclearRegulatory Commission Region I

2100 Renaissance

Blvd, Suite 100 King of Prussia, PA19406-2713 R.V.Guzman Senior Project Manager U.S.NuclearRegulatory Commission OneWhite FlintNorth, MailStop08-C2 11555 Rockville Pike Rockville, MD20852-2738 NRCSenior Resident Inspector Millstone PowerStation

Director, Radiation Division Department ofEnergy andEnvironmental Protection 79ElmStreet

Hartford, CT 06106-5127

Serial No.21-154 Docket No.50-423 ATTACHMENT 1

INon-PmpffetgyJ bl il MILLSTONE POWERSTATIONUNIT3 DOMINION ENERGYNUCLEARCONNECTICUT, INC.

Serial No.21-154 Docket No.50-423 Attachment 1,Page1of9 By letter datedNovember5,2020(Agencywide Documents AccessandManagement System (ADAMS) AccessionNo.ML20310A324),

Dominion Energy Nuclear Connecticut, Inc.

(DENC),

submitted alicense amendment request (LAR) totheNuclear Regulatory Commission (NRC) forMillstone PowerStation, UnitNo.3 (MPS3).

Theproposed amendmentwould revise TechnicalSpecification (TS) 6.9.1.6.b byadding WCAP-16996-P-A,Revision1, "Realistic LOCAEvaluation Methodology Applied totheFull Spectrum ofBreak Sizes (Full Spectrum LOCAMethodology),"

tothelist ofmethodologies approved forreference inthe Core Operating Limits Report (COLR) forMPS3.Theaddedreference identifies theanalyticalmethods usedtodetermine thecoreoperating limits forthelarge breaklossofcoolant accident (LBLOCA) eventdescribed intheMPS3Final Safety Analysis Report.

InanemaildatedMarch31,2021, theNRCissued a draft request foradditional information (RAI) related totheproposed LAR.OnApril 13,2021,theNRCstaff conducted aconference call with DENC staff toclarify therequest.

Inanemail dated April 15,2021,theNRCtransmitted thefinal version oftheRAl(ADAMS Accession No.

ML21105A115).

DENCagreed torespondto the RAlwithin 45daysofissuance, orno later thanMay31,2021 Thenon-proprietary version ofDENC'sresponse tothe RAI is providedinthis attachment.

BM!mrounSi Theaddedreference identifies theanalytical methods used to determine thecore operating limits forthelarge break loss ofcoolant accident (LBLOCA) event describedin theMPS3FinalSafety Analysis Report(FSAR),

Section 15.6.5, "Loss-of-Coolant f

Accidents Resulting froma Spectrum ofPostulated Piping Breakswithin theReactor Coolant Pressure Boundary."

Theamendment alsoproposes toremove an obsolete COLRreference that isnolonger usedtosupport MPS3corereload analysis.

TheNRCstaff hasdetermined thatadditional information isneededtocomplete its

review, asdescribed intherequest foradditional information (RAI) shownbelow.

Regulatory Basis:

Theregulations in10CFR50.46(b) require during LOCAevents, thefollowing criteria are met:

(1)Peakcladding temperature.

Thecalculated maximumfuelelement cladding temperature shall notexceed 2200"F.

(2)Maximumcladding oxidation.

Thecalculated total oxidation ofthecladding shall nowhere exceed 0.17times thetotal cladding thickness before oxidation.

Serial No.21-154 Docket No.50-423 Attachment 1,Page2of9 (3)

Maximum hydrogen generation.

Thecalculated total amountofhydrogen generated fromthechemical reaction ofthecladding withwater orsteamshall not exceed 0.01times thehypothetical amountthat wouldbegenerated ifallof the metal inthecladding cylinders surrounding

thefuel, excluding thecladding surrounding theplenum

volume, weretoreact.

(4)Coolablegeometry.

Calculated changes incoregeometry shall besuchthat the core remains amendable tocooling R.Aj1 InReference 1,Attachment 3,Limitation andCondition 2,under"Compliance" (a)

Thelicensee refers toLTR-NRC-18-30 (Reference3)andLTR-NRC-19-6 (Reference 4)which describechanges tothe Westinghouse small-break loss-of-coolant accident (LOCA) andLBLOCA emergency corecooling system(ECCS) evaluation modelsandtheimpact of these changes.

Thesereferences provide generically estimated effect on the peak cladding temperature (PCT).

In Reference 1,Attachment 3,Section 5.0, the FSLOCA Evaluation Model(EM) referred toisRevision 1,dated November 2016 whichisnotupdated by incorporating theerrors reported inReferences 3 and 4.Confirmthat theMPS3 LBLOCAanalysis wasperformed with the updated code afterremovingall errors reported inReferences 3and4.Ifthecodewasnot updated, provide

reasons, andjustify quantitatively thattheMPS3LBLOCA analysis performed (without updating thecode) hasnoimpact onPCT,maximum local oxidation (MLO),

core wideoxidation (CWO),

andminimum containment back pressure.

(b)References 3and4donotreport theerror identified inReference 5 that impacts thegammaenergy redistribution multiplier.

Ifapplicable toMPS3, provide an evaluation ofitsimpact ontheMPS3LBLOCAanalysis PCTresult and its thermal-hydraulic response.

Incaseitis notapplicable toMPS3,provide reasons.

i TheMPS3analysis using theFSLOCA EMutilized aversion oftheWCOBRA/TRAC-TF2 codewhich incorporated thechanges anderror corrections described inLTR-NRC-18-30 i

(Reference 3)andLTR-NRC-19-6 (Reference 4).

Itisconfirmed thattheanalysis was performed withtheupdated codewhich removed theerrors applicable totheFSLOCA EM,asreported inReferences 3and4.

Serial No.21-154 Docket No.50-423 Attachment 1,Page3of9 Theerror related togammaenergy redistribution discussed therein wasnotanerror in theFSLOCA EMortheWCOBRA/TRAC-TF2 code,butrather anerror intheplant-specific implementation ofthemethodology forNorth AnnaUnits 1and2.Assuch, the error wasnot reported inthe Westinghouse communications asamethodology error for theFSLOCAEM.The implementation error didnotoccur intheexecution oftheMPS3 analysis using the FSLOCA EM,andasaresult theas-approved methodology related to gammaenergy redistribution wascorrectlyapplied.

Therefore, theerror isnotapplicable totheMPS3FSLOCAEM analysis.

RAl-2 InReference 1,Attachment 3,Section3.0, thedescriptionof Region IIanalysis doesnot provide theLBLOCAbreak spectrum scenarios that wereanalyzed.

Provide thebreak

spectrum, i.e.,

thePCTsversus break areasand MLOs versus PCTsthat wereanalyzed fromwhich thelimiting results reported inTable 5 were obtained.

M

[

Ja,C Theuncertainty analysis methodology usedintheFSLOCAEMisdescribed inSection 30 ofWCAP-16996-P-A, Revision 1.A MonteCarlosampling ofall uncertainty contributors leads tothegeneration ofasample ofsimulated results fromwhich upper tolerance limits arederived fortheanalysis figures ofmerit (PCT,MLO,CWO).

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Serial No.21-154 Docket No.50-423 Attachment 1,Page8of9 E

InReference 1,Attachment 3,Section 4.0,undercompliance with 10CFR50.46(b)(4),

second paragraph, last sentence

states, "Inboard griddeformation duetocombined LOCAandseismic loadsisnotcalculated tooccur forMillstone Unit 3."Thisstatement doesnot explicitly state howthis conclusion wasdetermined.

Provide thetechnical basis forthis assertion.

M Section 32.1ofthe NRC-approved FSLOCA EM(Reference 2)discusses that theeffects ofLOCAandseismic loads onthe core geometry donotneedtobeconsidered unless fuel assembly grid deformation extends beyond thecoreperiphery (i.e.,

deformation ina fuel assembly with nosides adjacentto the corebaffle plates).

TheFSLOCAEManalysis doesnotaffect theexisting analysis ofrecord related tothecombined LOCAandseismic loads.

Thisconclusion isretained from prior calculations andiscredited inthecurrent LOCAdesign basis analysis.

Asdescribedin Section 4.2.3.4.1oftheMPS3FSAR,the combined LOCAandseismic loads remain below the allowable grid strength:

"Themaximumgridimpact forces forboth the seismic accidentandasymmetric LOCAoccur attheperipheral fuel assembly locations adjacent tothebaffle wall.

The maximumgrid impact forces result frompostulated LOCA andseismicloadings, and arerequired tobeless thantheallowable grid crush strength.

A calculation ofthe maximumLOCAandseismic gridimpact

forces, combined using thesquare root sumofthesquares method inaccordance with SRP4.2, Appendix A,demonstrated that themaximumvalue isbelow theallowable grid strength."

7 REFERENCES 1.Dominion EnergyNuclear Connecticut, Incletter toNRC, "Dominion Energy Nuclear Connecticut, Inc.Millstone PowerStation Unit3 Proposed License Amendment Request Addition ofAnalytical Methodology totheCoreOperating Limits Report foraLargeBreak LossofCoolant Accident (LBLOCA),"

November 5,2020,(ADAMS Accession No.ML20310A324).

2.Westinghouse Topical Report WCAP-16996-P-A, Revision 1,"Realistic LOCA Evaluation Methodology Applied totheFullSpectrum ofBreakSizes(FULL SPECTRUM LOCAMethodology),"

November 2016.

l 3.Westinghouse Electric Companyletter toNRC,LTR-NRC-18-30, "U.S.

Nuclear Regulatory Commission 10CFR50.46AnnualNotification andReporting for 2017,"

July 18,2018(ADAMS Accession No.ML19288A174).

Serial No.21-154 Docket No.50-423 Attachment 1,Page9of9 4.

Westinghouse Electric Companyletter toNRC,LTR-NRC-19-6, "U.S.

Nuclear Regulatory Commission10CFR50.46AnnualNotification andReporting for 2018,"

February 7,2019(ADAMS Accession Package No.ML19042A378).

5.Virginia Electric andPowerCompanyletter toNRC,"Virginia Electric andPower Company North AnnaPowerStation Units 1and2Proposed License Amendment Request Addition ofAnalytical Methodology totheCoreOperating Limits Report fora Full Spectrum LossofCoolant Accident (FSLOCA)

GammaEnergy RedistributionInformation,"

August31, 2020,(ADAMS Accession No.

ML20244A336).

p 1

Serial No.21-154 Docket No.50-423 ATTACHMENT 2

fN.gjlf.tgpffetary.1 t

I MILLSTONEPOWERSTATIONUNIT3 DOMINIONENERGYNUCLEARCONNECTICUT, INC.

Serial No.21-154 Docket No.50-423 Attachrnent 2,Page1of3 Westinghouse Non-Proprietary Class 3

CAW-21-5177 Page1of3 COMMONWEALTH OFPENNSYLVANIA:

COUNTYOFBUTLER:

(1) I,Camille T.zozula, have beenspecificallydelegated andauthorized toapply for withholding andexecutethis Affidavit onbehalf ofWestinghouse Electric Company LLC (Westinghouse).

(2) Iamrequesting theproprietary portions ofLTR-LIS-21-115, Attachment 1bewithheld from public disclosure under 10CFR2.390.

(3) Ihavepersonal knowledge ofthecriteria andprocedures utilized byWestinghouse in designating information asatrade

secret, privileged, oras confidential commercial or financial information.

(4) Pursuant to10CFR2.390, thefollowing isfurnished for consideration bythe Commission in determining whether theinformation sought tobewithheld from publicdisclosure should be withheld.

(i) Theinformation sought tobewithheld frompublic disclosure isownedandhas been held inconfidence byWestinghouse andisnotcustomarily disclosed tothe public.

(ii)Theinformation sought tobewithheld isbeing transmitted totheCommission in confidence

and, toWestinghouse's knowledge, isnotavailable inpublic sources.

(iii)

Westinghouse notes that ashowing ofsubstantial harmisnolonger anapplicable

,I criterion foranalyzing whether adocument should bewithheld frompublic disclosure.

Nevertheless, public disclosure ofthis proprietary information islikely to cause substantial harmtothecompetitive position ofWestinghouse because itwould enhance theability ofcompetitors toprovide similar technical evaluation justifications andlicensing defense services forcommercial power reactors without commensurate expenses.

Also, public disclosure oftheinformation wouldenable

• • • Thisrecord wasfinal approved on5/5/2021 5:30:04 PM.(This statement wasadded bythePRIMEsystem uponitsvalidation)

Serial No.21-154 Docket No.50-423 Attachment 2,Page2of3 Westinghouse Non-Proprietary Class 3

CAW-21-5177 Page2of3 others tousetheinformation tomeetNRCrequirements forlicensing documentation without purchasing theright tousetheinformation (5) Westinghouse haspolicies inplace toidentify proprietary information.

Under that

system, information isheld inconfidence ifitfalls inoneormoreofseveral

types, therelease of which might result inthe loss of anexisting orpotential competitive advantage, asfollows:

(a)Theinformation reveals thedistinguishing aspects ofaprocess (or component, structure,

tool, method, etc.)

whereprevention ofits usebyany ofWestinghouse's competitors without license fromWestinghouse constitutes acompetitive economic advantage overother companies.

(b) Itconsists ofsupporting

data, including test data, relative toaprocess (or component, structure,

tool, method, etc.),

the application ofwhich data secures acompetitive economic advantage (e.g.,

by optimization orimproved marketability).

(c)Itsusebyacompetitor wouldreduce hisexpenditure ofresources or improve hiscompetitive position inthedesign, manufacture,

shipment, installation, assurance ofquality, orlicensing asimilar product.

(d) Itreveals costorprice information, production capacities, budget

levels, or commercial strategies ofWestinghouse, its customers orsuppliers.

(e)Itreveals aspects

ofpast, present, orfuture Westinghouse orcustomer funded development plans andprograms ofpotential commercial value to Westinghouse.

(f) Itcontains patentable

ideas, forwhich patent protection maybedesirable.

• • • This record wasfinal approved on5/5/2021 5:30:04 PM.(This statement wasaddedbythePRIMEsystem uponitsvalidation)

Serial No.21-154 Docket No.50-423 Attachment 2,Page3of3 Westinghouse Non-Proprietary Class 3

CAW-21-5177 Page3of3 (6) Theattached documents arebracketed andmarked toindicate thebases forwithholding.

The justification for withholding isindicated inbothversions bymeansoflower-case letters (a) through (f) located asasuperscript immediately following thebrackets enclosing eachitemof information being identified asproprietary orinthemargin opposite such information.

These lower-case letters referto the types ofinformationWestinghouse customarily holds in confidence identified inSections (5)(a) through(f) ofthis Affidavit.

Ideclare that theaverments offact setforthin this Affidavit aretrueandcorrect tothebest ofmy i

knowledge, information, andbelief.

Ideclare under penalty ofperjury that theforegoing istrueand correct.

i Executed on:04May2021 Q

a fd Camille T.zozula, Manager Regulatory Compliance &

Corporate Licensing

1. 8 i

lfI E

i i

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• • • Thisrecord wasfinal approved on5/5/2021 5:30:04 PM.(This statement wasaddedbythePRIMEsystem uponitsvalidation)