ML14080A335

Request for Additional Information Related to License Amendment Request to Updated Final Safety Analysis Report Changes Associated with Hydrologic Analysis

ML14080A335
Person / Time
Site:	Watts Bar
Issue date:	03/21/2014
From:	Andrew Hon Plant Licensing Branch II
To:	James Shea Tennessee Valley Authority
Andy Hon
References
TAC ME9130
Download: ML14080A335 (3)

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Mr. Joseph W. Shea Han, Andrew Friday, March 21, 2014 2:05 PM Shea, Joseph W Uwshea@tva.gov); Schrull, Edward Dustin (edschrull@tva.gov); Arent, Gordon (garent@tva.gov); Hess, Thomas A (tahess@tva.gov)

Lingam, Siva; Poole, Justin; Hoang, Dan; McMurtray, Anthony; Cheng, Yuan; Quichocho, Jessie WATTS BAR NUCLEAR STATION, UNIT 1-REQUEST FOR ADDITIONAL INFORMATION RELATED TO UCENSE AMENDMENT REQUEST TO UPDATED FINAL SAFETY ANALYSIS REPORT CHANGES ASSOCIATED WITH HYDROLOGIC ANALYSIS (TAC NO. ME9130)

Vice President, Nuclear Licensing Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801

SUBJECT:

WATTS BAR NUCLEAR STATION, UNIT 1 -REQUEST FOR ADDITIONAL INFORMATION RELATED TO LICENSE AMENDMENT REQUEST TO UPDATED FINAL SAFETY ANALYSIS REPORT CHANGES ASSOCIATED WITH HYDROLOGIC ANALYSIS (TAC NO. ME9130)

Dear Mr. Shea:

By letter dated July 19, 2012, you submitted an application for license amendment to revise the Updated Final Safety Analysis Report (UFSAR) to adopt a revised hydrologic analysis for Watts Bar Nuclear Plant (WBN)

Unit 1. These changes to the WBN Unit 1 UFSAR incorporated updates previously submitted in support of the initial licensing of WBN Unit 2 as well as more recently discovered input information.

The U.S. Nuclear Regulatory Commission (NRC) staff is reviewing your submittal and has determined that additional information is required to complete the review. The specific information requested is addressed in the enclosure to this letter. The proposed questions were discussed by telephone with your staff on March 21 2014. Your staff confirmed that these questions did not include proprietary or security-related information. We request you to respond by March 28, 2014 and your staff will confirm or propose alternate date of your response by March 24, 2014.

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The NRC staff considers that timely responses to RAis help ensure sufficient time is available for staff review and contribute toward the NRC's goal of efficient and effective use of staff resources. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-8480 or via e-mail Andrew.Hon@ nrc.gov.

Docket No. 50-390 ADAMS Accession No. ML14080A335

Enclosure:

Request for Additional Information Sincerely, RIA Andrew Hon, Project Manager Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation 2

REFERENCES:

REQUEST FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST TO UPDATED FINAL SAFETY ANALYSIS REPORT CHANGES ASSOCIATED WITH HYDROLOGIC ANALYSIS TENNESSEE VALLEY AUTHORITY WATTS BAR NUCLEAR PLANT, UNIT 1 DOCKET NO. 50-390

1) Letter from J.W. Shea, TVA, to NRC Document Control Desk, "Application to Revise Watts Bar Nuclear Plant Unit 1 Updated Final Safety Analysis Report Regarding Changes to Hydrologic Analysis, TAC No.

ME8200 (WBN-UFSAR-12-01)," dated July 19,2012. (ADAMS Accession No.: ML12236A167)

2) Letter from R.A. Hruby, Jr. to NRC Document Control Desk, Watts Bar Nuclear Plant (WBN) Unit 2-Long-Term Stability Analysis Methodology," dated September 6, 2012. (ADAMS Accession No.:

ML12279A191)

EMCB-RAI-2.4.3-7 The Reference 1 license amendment request (LAR) seeks approval to revise the WBN 1 Updated Safety Analysis Report (UFSAR) to adopt a revised hydrologic analysis for the WBN 1 site. For embankment breaching, the updated hydrologic analysis in Reference 1 assumed that no breaching would occur except Watts Bar West Saddle Dike which fails completely. Therefore, the Cherokee and Douglas dams were assumed to not be breached with the revised hydraulic analysis and new peak maximum flood (PMF) height and flow.

Reference 2 notes that TVA recently completed finite element analyses to re-evaluate the stability analysis for both the Cherokee and Douglas Dams utilizing current industry standards. This re-evaluation indicated the potential for failure of portions of the dams in extreme flood events. As a result, the Cherokee and Douglas dams will require modifications to ensure that the dams meet current industry stability criteria. These modifications are currently scheduled to not be completed until the end of 2014. TVA also noted in Reference 2 that these new analyses do not invalidate the nuclear design basis analysis of record.

Please provide a description of which stability analysis for the Cherokee and Douglas dams will be the analysis of record if the proposed LAR noted by Reference 1 is approved and provide any additional details regarding the stability assumptions for these dams in Reference 1 based on the information provided to the NRC in Reference 2.

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