ML15310A085

Watts Bar Nuclear Plant, Units 1 and 2 (Public Version) - Staff Assessment of Response to Request for Information Pursuant to 10 CFR 50.54(f) Flood Causing Mechanisms Reevaluation

ML15310A085
Person / Time
Site:	Watts Bar
Issue date:	12/01/2015
From:	Uribe J F Japan Lessons-Learned Division
To:	Shea J W Tennessee Valley Authority
Uribe J F
References
TAC MF5858, TAC MF5857
Download: ML15310A085 (3)

Text

{{#Wiki_filter:. OFFICIAL USE ONbY SECYRITY RELATED INFORMATION UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 Mr. Joseph W. Shea Vice President, Nuclear Licensing Tennessee Valley Authority 1101 Market Street, LP 3R-C Chattanooga, TN 37402-2801 December 1, 2015

SUBJECT:

WATTS BAR NUCLEAR PLANT, UNITS 1 AND 2 -STAFF ASSESSMENT OF RESPONSE TO REQUEST FOR INFORMATION PURSUANT TO 10 CFR 50.54(f) FLOOD-CAUSING MECHANISMS REEVALUATION (TAC NOS. MF5857 AND MF5858)

Dear Mr. Shea:

By letter dated March 12, 2012, the U.S. Nuclear Regulatory Commission (NRC) issued a request for information pursuant to Title 10 of the Code of Federal Regulations, Section 50.54(f) (hereafter referred to as the 50.54(f) letter). The request was issued as part of implementing lessons-learned from the accident at the Fukushima Dai-ichi nuclear power plant. Enclosure 2 to the 50.54(f) letter requested licensees to reevaluate flood-causing mechanisms using present-day methodologies and guidance. By letters dated March 12, 2015 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML 15084A323), and June 16, 2015 (ADAMS Accession No. ML 15169A906, Non-Public, Security Related Information), Tennessee Valley Authority (TVA, the licensee) responded to this request for Watts Bar Nuclear Plant, Units 1 and 2 (Watts Bar). By letter dated September 3, 20151, the NRC staff transmitted to TVA a summary of the staff's review of the licensee's reevaluated flood-causing mechanisms. The enclosed staff assessment provides the documentation supporting the NRC staff's conclusions summarized in the letter1. As stated in the letter, the reevaluated flood hazard results for local intense precipitation and streams and rivers were not bounded by the current design-basis flood hazard. In order to complete its response to Enclosure 2 to the 50.54(f) letter, the licensee is expected to submit a revised integrated assessment or a focused evaluation, as appropriate, to address these reevaluated flood hazards, as described in the NRC's September 1, 2015, letter (ADAMS Accession No. ML 15174A257). The enclosed staff assessment, determined that you provided sufficient information in response to the 50.54(f) letter. This closes out the NRC's efforts associated with TAC Nos. MF5857 and MF5858. The Enclosure transmitted herewith contains Security-Related Information. When separated from the Enclosure, this document is decontrolled. 1 ADAMS Accession No. ML 152398292 Of'.f'.ICIAL USE ONLY SECURITY RELATED INFORMATION OFFICIAL' 'SE ONLY SECURITY RELATED INFORMATION J. Shea If you have any questions, please contact me at (301) 415-3809 or e-mail at Juan.Uribe@nrc.gov. Docket Nos. 50-390 and 50-391

Enclosure:

Staff Assessment of Flood Hazard Reevaluation Report cc w/encl: Distribution via Listserv Sincerely, -{-Juan Uribe, Project Manager Hazards Management Branch Japan Lessons-Learned Division Office of Nuclear Reactor Regulation OFFICIAL I !SE ONLY SECURITY REb.ATED INFORMATION

Pkg. ML 1531 OA080; PUBLIC Letter. ML 15310A085; NON PUBLIC. ML 15302A408 *via email OFFICE NRR/JLD/JHMB/PM NRR/JLD/LA NRO/DSEA/RHM2/BC NAME JUribe SLent CCook DATE 11/9/2015 11/9/2015 11/27/2015 OFFICE NRR/JLD/JHMB/BC NRR/JLD/JHMB/PM NAME MS hams JUribe DATE 12/1/2015 12/1/2015}}