From kanterella
Jump to: navigation, search

Tennessee Valley Authority Presentation to NRC on Tpbar LAR 8-12-15
Person / Time
Site: Watts Bar Tennessee Valley Authority icon.png
Issue date: 08/12/2015
Tennessee Valley Authority
To: Dion J A
Watts Bar Special Projects Branch
Dion J A, NRR/DORL/LPWB, 415-1349
Download: ML15225A377 (17)


Watts Bar Nuclear Plant Unit 1TPBAR Loading Increase License Amendment RequestAlignment Meeting 2AgendaIntroduction and Purpose WBN Unit 1 TPBAR Loading PlansLicensing Activities Schedule Timeline for WBN Unit 1 TPBAR ProgramProposed Technical Specification ChangesPost-LOCA SubcriticalityAnalysisRadiological AnalysisNRC Review with TVA and DOE SupportSummary 3IntroductionTVA requested a change to the Watts Bar Nuclear Plant (WBN) Unit 1 Technical Specifications to increase the number of Tritium Producing Burnable Absorber Rods (TPBARs) that can be irradiated from 704 to 1792TVA requested NRC approval by August 31, 2016, to support an increased TPBAR loading in Cycle 15 (spring of 2017) for DOE National Nuclear Security Administration (NNSA) needs 4PurposeProvide a high level overview of the License Amendment Request (LAR)Discuss the schedule of the LAR review to meet the NNSA need dateOffer TVA and DOE support of NRC technical reviews 5WBN Unit 1 TPBAR Loading PlansCycleDateTPBAR LoadingTech Spec Limit C13April 2014 704 704 C14October 2015 704 704 C15March 2017 1104 1792*C16October 2018 1504 1792*C17April 2020 1792 1792** Proposed LAR Licensing Activities Schedule 6 July 2014 June 2017 January 2015 January 2016 January 2017 1792 TPBAR License Amendment Key MilestonesApril 2015 - August 2016 NRC Review August 2016 NRC SER for 1792 TPBARs June 2015 Submit LAR Supplemental Response April 2017 Cycle 15 Startup August 2014 Pre-Application Meeting with NRC March 2016 Start Cycle 15 Fuel Design August 2015 Review Kickoff Meeting with NRC March 2015 Submit LAR February 2016 NRC Management Meeting on Review Status March 2016 - October 2016Fuel Design & Delivery July 2016 Start Cycle 15 Fuel FabricationFebruary 2016 7Timeline for WBN Unit 1 TPBAR ProgramMay 1996 -DOE/NRC Memorandum of Understanding (MOU) formed the basis for NRC review and consultation on possible use of Commercial Light Water Reactors (CLWRs) for producing tritiumOct 1996 -TVA agreed to irradiate 32 TPBARs in four Lead Test Assemblies (LTAs) at WBN Unit 1May 1997 -NUREG-1607 (LTAs) issuedSept 1997

-WBN Unit 1 Amendment 8 (LTAs) issuedOct 1997 -32 TPBARs loaded in Cycle 2 8Timeline for WBN Unit 1 TPBAR Program (cont.)Sept 2002

-WBN Unit 1 Amendment 40 approved up to 2304 TPBARsOct 2003 -WBN Unit 1 Amendment 48 reduced loading to 240 TPBARs to address post-LOCA subcriticalitymargin issueOct 2003 -240 TPBARs loaded in Cycle 6Mar 2005 -TVA notified NRC of interim cumulative TPBAR tritium release limits

-While higher than projected permeation rates were investigated Apr 2005 -240 TPBARs loaded in Cycle 7 9Timeline for WBN Unit 1 TPBAR Program (cont.)Nov 2006 -240 TPBARs loaded in Cycle 8Jan 2008 -WBN Unit 1 Amendment 67 approved up to 400 TPBARsMar 2008 -368 TPBARs loaded in Cycle 9May 2009 -WBN Unit 1 Amendment 77 approved up to 704 TPBARs Oct 2009 -240 TPBARs loaded in Cycle 10May 2011 -544 TPBARs loaded in Cycle 11 10Timeline for WBN Unit 1 TPBAR Program (cont.)Oct 2012 -544 TPBARs loaded in Cycle 12May 2014 -704 TPBARs loaded in Cycle 13Jan 2015 -TVA notified NRC of updated program controls to remove interim measures for permeation while maintaining doses and release concentrations within regulatory requirementsOct 2015 -704 TPBARs planned for loading in Cycle 14 11Current License Amendment RequestPre-application meeting with NRC on August 14, 2014LAR submitted to NRC on March 31, 2015Correction letter submitted to NRC on April 28, 2015Provided supplemental information in letters dated May27,2015, and June 15, 2015, in response to NRC requestsNRC accepted LAR for review on June 26, 2015 Proposed Technical Specification ChangesRevise Technical Specification 4.2.1 to reflect new upper limit of 1792 TPBARsRevise Surveillance Requirement to remove dependence of accumulator boron concentration on number of TPBARsRevise Surveillance Requirement to remove dependence of RWST boron concentration on number of TPBARs 12Number of TPBARsBoron Concentration Ranges 0 -xxxx>yyyyppm and <zzzz ppm 13Post-LOCA SubcriticalityAnalysisPost-LOCA subcriticalityanalysis method consistent with method previously used in WBN Unit 1 Amendment 77 with the following key changes:

-Eliminated 40 gpmdilution source in containment sump (requires plant modifications)

-Updated time

-dependent lithium leaching rate based on testingRCS boron concentration reduced by increased Integral Fuel Burnable Absorber (IFBA) loadingResults demonstrate sufficient margin for 1792 TPBARs 14Radiological AnalysisRadiological analysis in WBN Unit 1 Amendment 40 assumed 2304 TPBARs and permeation rate of 1 Ci/TPBAR/yearCurrent LAR supported by new radiological analysis for:

-Realistic scenario of up to 1900 TPBARs at 5 Ci/TPBAR/year

-Bounding (Design Basis) scenario of up to 2500 TPBARs at 10 Ci/TPBAR/yearRegulatory criteria in 10 CFR Part 20, Part 50.67, Part 50 Appendix I, and Part 100 are all satisfied 15NRC Review with TVA and DOE SupportDue to the importance of meeting the NNSA need for increased TPBAR irradiation in WBN Unit 1 Cycle 15, TVA requests essential completion of NRC technical reviews prior to initiation of fuel and core design activities on March 2, 2016 TVA and DOE will provide any support needed for expeditious technical reviews

-TVA and DOE are willing to send technical experts to meet with NRC reviewers to provide any needed background information or discussion of the various LAR sectionsTVA requests at least monthly updates from the NRC Project Manager regarding the progress of the technical reviews 16SummaryLAR requests increased TPBAR loadings beginning with WBN Unit 1 Cycle 15 to meet NNSA needsLAR addresses post

-LOCA subcriticalitymargin, required plant modifications, lithium leaching rates, and radiological analysis TVA and DOE offer technical support for NRC reviewersTVA requests monthly progress updates from NRC Project ManagerTVA requests NRC technical reviews near completion by March 2, 2016TVA requests NRC approval by August 31, 2016