ML16194A115

Staff Assessment of the Response to 10 CFR 50.54(f) Information Request - Flood Causing Mechanism Reevaluations(Public)

ML16194A115
Person / Time
Site:	Sequoyah
Issue date:	07/13/2016
From:	Juan Uribe Japan Lessons-Learned Division
To:	James Shea Tennessee Valley Authority
References
CAC MF6032, CAC MF6033
Download: ML16194A115 (3)

Text

OFFICIAL USE ONLY SECURITY RELATED INFORMATION UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 July 13, 2016 Mr. Joseph W . Shea Vice President, Nuclear Licensing Tennessee Valley Authority 1101 Market Street, LP 3R-C Chattanooga, TN 37402-2801

SUBJECT:

SEQUOYAH NUCLEAR PLANT, UNITS 1AND2-STAFF ASSESSMENT OF RESPONSE TO 10 CFR 50.54(f) INFORMATION REQUEST- FLOOD-CAUSING MECHANISM REEVALUATION (CAC NOS. MF6032 AND MF6033)

Dear Mr. Shea:

By letter dated March 12, 2012, the U.S. Nuclear Regulatory Commission (NRC) issued a request for information pursuant to Title 1O 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 letter dated March 12, 2015 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML15071A462) ,

Tennessee Valley Authority (TVA, the licensee) responded to this request for Sequoyah Nuclear Plant, Units 1 and 2 (Sequoyah) .

By letter dated September 3, 2015 (ADAMS Accession No. ML15240A163), the NRC staff sent 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 letter. 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 focused evaluation or an integrated assessment, as appropriate, to address these reevaluated flood hazards, as described in the NRC's September 1, 2015, letter (ADAMS Accession No. ML15174A257).

The Enclosure transmitted herewith contains Security-Related Information. When sep arated from the Enclosure, this document is decontrolled.

OFFICIAL USE ONLY SECURITY RELATED INFORMATION

OFFICIAL USE 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.

Ju n Uribe, Pro ct Manager Hazards Management Branch Japan Lessons-Learned Division Office of Nuclear Reactor Regulation Docket Nos. 50-327 and 50-328

Enclosure:

Staff Assessment of Flood Hazard Reevaluation Report cc w/o encl: Distribution via Listserv OFFICIAL USE ONLY*SECURITY RELATED INFORMATION

Letter: ML16194A115 (PUBLIC) , ML16188A274 ~ NON-PUBLIC) *via email OFFICE NRR/JLD/JHMB/PM NRR/JLD/LA N RO/DSEA/RHM2/BC NAME JUribe SLent CCook DATE 07/07/2016 07/07/2016 06/29/2016 OFFICE NRR/JLD/JHMB/BC(A) NRR/JLD/JHMB/PM NAME GBowman JUribe DATE 07/13/2016 07/13/2016