ML15314A061
| ML15314A061 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 11/24/2015 |
| From: | Juan Uribe Japan Lessons-Learned Division |
| To: | Koehl D South Texas |
| Marshall, Michael, NRR/JLD 415-2871 | |
| References | |
| CAC MF1110, CAC MF1111 | |
| Download: ML15314A061 (3) | |
Text
Mr. Dennis L. Koehl President and CEO/CNO UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 November 24, 2015 STP Nuclear Operating Company South Texas Project P.O. Box 289 Wadsworth, TX 77 483
SUBJECT:
SOUTH TEXAS PROJECT, UNITS 1AND2-MITIGATING STRATEGIES ASSESSMENT WITH RESPECT TO THE REEVALUATED FLOOD HAZARDS SUBMITTED IN RESPONSE TO 10 CFR 50.54(f) INFORMATION REQUEST -FLOOD-CAUSING MECHANISM REEVALUATION (CAC NOS. MF1110 AND MF1111)
Dear Mr. Koehl:
The purpose of this letter is to describe the next steps following the review of the reevaluated flood hazard as directed by the Commission.
Specifically, this letter addresses the next steps associated with the mitigation strategies assessment (MSA) with respect to the reevaluated flood hazard. By letter dated March 12, 2012 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML12053A340), 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 letter dated March 11, 2013 (ADAMS Accession No ML13079A806), STP Nuclear Operating Company (STP, the licensee) responded to this request for South Texas Project, Units 1 and 2 (STP). This response was supplemented by letters dated January 22, 2014 (ADAMS Accession No. ML14041A336) and February 13, 2014 (ADAMS Accession No. ML14056A195).
By letter dated September 30, 2014 (ADAMS Accession No. ML14259A195), the NRC staff transmitted to you its staff assessment of the information provided in the above mentioned letters. The NRC staff has completed its review of the information provided.
The current flood hazard reevaluation approach is described in NRC letter dated September 1, 2015 (ADAMS Accession No. ML15174A257), concerning the coordination of requests for information regarding flooding hazard reevaluations and mitigating strategies for basis external events. This letter describes the changes in the NRC's approach to the flood hazard reevaluations that were approved by the Commission in its Staff Requirements Memorandum (ADAMS Accession No. ML15209A682) to COMSECY-15-0019 (ADAMS Accession No. ML15153A104) that described the NRC's mitigating strategies and flooding hazard reevaluation action plan.
D. Koehl As described in the staff assessment, the NRC staff confirmed that the licensee responded appropriately to Enclosure 2 of the 50.54(f) letter. The NRC staff confirmed that the reevaluated hazard results for each reevaluated flood-causing mechanism are bounded by the current design-basis flood hazard and an integrated assessment or a focused evaluation is not necessary for STP. The NRC staff has no additional information needs at this time with respect to Enclosure 2 of the 50.54(f) letter. The September 1, 2015, letter described expectations for sites to perform an assessment of their mitigation strategies with respect to the reevaluated hazard. The licensee is expected to perform an MSA for STP. The Nuclear Energy Institute (NEI) guidance document NEI 12-06, "Diverse and Flexible Coping Strategies (FLEX) Implementation Guide" is currently being revised. This revision will include a methodology to perform an MSA with respect to the reevaluated flood hazards. The NRC staff has concluded that the licensee's reevaluated hazard information is suitable for the assessment of mitigation strategies developed in response to Order EA-12-049 (i.e., defines the mitigation strategies flood hazard information described in the revised NEI 12-06 guidance currently being finalized by the industry and NRC staff). If you have any questions, please contact me at (301) 415-3809 or e-mail at Juan.Uribe@nrc.gov.
Docket Nos. 50-498 and 50-499 cc: Distribution via Listserv Juan ribe, Project Manager Hazards Management Branch Japan Lessons-Learned Division Office of Nuclear Reactor Regulation D. Koehl As described in the staff assessment, the NRC staff confirmed that the licensee responded appropriately to Enclosure 2 of the 50.54(f) letter. The NRC staff confirmed that the reevaluated hazard results for each reevaluated flood-causing mechanism are bounded by the current design-basis flood hazard and an integrated assessment or a focused evaluation is not necessary for STP. The NRC staff has no additional information needs at this time with respect to Enclosure 2 of the 50.54(f) letter. The September 1, 2015, letter described expectations for sites to perform an assessment of their mitigation strategies with respect to the reevaluated hazard. The licensee is expected to perform an MSA for STP. The Nuclear Energy Institute (NEI) guidance document NEI 12-06, "Diverse and Flexible Coping Strategies (FLEX) Implementation Guide" is currently being revised. This revision will include a methodology to perform an MSA with respect to the reevaluated flood hazards. The NRC staff has concluded that the licensee's reevaluated hazard information is suitable for the assessment of mitigation strategies developed in response to Order EA-12-049 (i.e., defines the mitigation strategies flood hazard information described in the revised NEI 12-06 guidance currently being finalized by the industry and NRC staff). If you have any questions, please contact me at (301) 415-3809 or e-mail at Juan.Uribe@nrc.gov.
Sincerely, IRA! Juan Uribe, Project Manager Hazards Management Branch Japan Lessons-Learned Division Office of Nuclear Reactor Regulation Docket Nos. 50-498 and 50-499 cc: Distribution via Listserv DISTRIBUTION:
PUBLIC VHall, NRR RidsNrrDorllpl4-1 Resource RidsRgn4MailCenter Resource RidsOpaMail Resource JThompson, NRO ARivera-Varona, NRO LQuinn-Willingham, NRO BHayes, NRO JLD R/F JUribe, NRR RidsNrrDorl Resource RidsNrrLASLent RidsAcrsAcnw_MailCtr Resource LHibler, NRO KErwin, NRO RidsNroDsea Resource RidsNRRJLD Resource MShams, NRR RidsNrrPMSouthTexas Resource RidsOgcMailCenter Resource PChaput, NRO CCook, NRO ACampbell, NRO MBensi, NRO ADAMS Accession No.: ML15314A061
- via email OFFICE NRR/JLD/JHMB/PM NRR/JLD/LA NAME MMarshall SLent DATE 11/23/2015 11/23/2015 OFFICE NRR/JLD/JHMB/BC NRR/JLD/JHMB/PM NAME MS hams JUribe DATE 11/24/2015 11/24/2015 OFFICIAL RECORD COPY