ML15349A808

2015/06/30 Email from W.Craft to R.Guzman Millstone Unit 3 Information Regarding LAR to Adopt Dominion Core Design and Safety Analysis Methods

ML15349A808
Person / Time
Site:	Millstone
Issue date:	06/30/2015
From:	Craft W D Dominion Resources Services
To:	Guzman R V Plant Licensing Branch 1
Guzman R V
References
TAC MF6251
Download: ML15349A808 (1)

Text

1Guzman, RichardFrom:Wanda D Craft (Generation - 6) <wanda.d.craft@dom.com>Sent:Tuesday, June 30, 2015 10:23 AMTo:Guzman, RichardCc:John Harrell (Generation - 6)Subject:[External_Sender] Information related to MPS3 LAR to Adopt Dominion Core Design and Safety Analysis MethodsCategories:FollowupRich,TheNAFgroupdiscoveredadiscrepancybetweentheMPS3RETRANBaseModelPressurizerShellHeatConductorandtheDominionRETRANTopicalReportthispastweekend(June27/28).TheMPS3RETRANbaseinputdeckmodelsthepressurizershellasaheatconductor,whichdiffersfromTopicalReportVEPFRD41.VEPFRD41states,"Dominioncontinuestomodelthenonequilibriumwallasanadiabaticsurface."Thismodelisnotusedinanyanalysesofrecord,sothisdiscrepancyhasnoimpactonplantlicensingoroperations.However,theRETRANbasemodelwasusedtobenchmark/replicateWestinghouseanalysesofrecordinsupportofthesubjectLARsubmittedonMay8,2015forgenericNRCapprovalofapplicationofDominionreloaddesignanalysismethodstoMPS3.EachofthefivebenchmarkingcasessupportingtheMay8,2015LARwerererunwiththeneededcorrection.ThisresultedineitheressentiallynodifferenceorimprovedreplicationoftheWestinghouseanalysisofrecordresults(i.e.inthecaseoftheofthepredictedpressurizerwatervolumeforthelossofnormalfeedwaterbenchmark).

ThisinformationwasnotknownatthetimeofourJune25clarificationcall.WeanticipatethatmodifiedgraphsandtextfortheaffectedLossofNormalFeedwaterbenchmarkcaseintheLARmaybeneededbytheNRCtechreviewertocompletehisreviewoftheLAR,andthathemaywishforustoprovidethisadditionalinformationinconjunctionwithresponsestoforthcomingRAIs.

ACRisbeingwrittentodocumentthisissue.Iwillbehappytosendyouacopyafterithasbeensubmitted.Ifyouhaveanyquestions,pleaseletmeknow.Weareavailabletodiscussthisatanytime.Thanks. Wanda D. Craft Nuclear Licensing and Operations Support Dominion Resources Services, Inc (804) 273-4687 tie-line 730-4687 CONFIDENTIALITY NOTICE: This electronic message contains information which may be legally confidential and or privileged and does not in any case represent a firm ENERGY COMMODITY bid or offer relating thereto which binds the sender without an additional express written confirmation to that effect. The information is intended solely for the individual or entity named above and access by anyone else is unauthorized. If you are not the intended recipient, any disclosure, copying, distribution, or use of the contents of this information is prohibited and may be unlawful. If you have received this electronic transmission in error, please reply immediately to the sender that you have received the message in error, and delete it. Thank you.