ML17030A044

Mitigating Strategies Assessment (MSA) Report for the New Seismic Hazard Information NEI 12-06, Appendix H, Revision 2, H.4.1 Path 1: GMRS ≪ SSE

ML17030A044
Person / Time
Site:
Issue date:	01/26/2017
From:	McCool T P Luminant Power
To:	Document Control Desk, Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation
References
CAC MF3937, CAC MF3938, CP-201700084, TXX-17009
Download: ML17030A044 (2)

Text

II Thomas P. McCool Site Vice President Thomas.McCool@Luminant.com Luminant Power P 0 Box 1002 6322 North FM 56 Glen Rose, TX 76043 Luminant CP-201700084 TXX-17009 Ref: T 254 897 6042 c 817 776 0308 F 254 897 6652 10 CFR 50.54(£) January 26, 2017 U.S. Nuclear Regulatory Commission Attention:

Document Control Desk Director, Office of Nuclear Reactor Regulation Washington, DC 20555-0001

REFERENCES:

Comanche Peak Nuclear Power Plant (CPNPP) Units 1 and 2, Docket Nos. 50-445 and 50-446, 72-74 Mitigating Strategies Assessment (MSA) Report for the New Seismic Hazard Information NEI 12-06, Appendix H, Revision 2, H.4.1Path1:

GMRS :S SSE 1. Nuclear Energy Institute (NEI) guidance, NEI 12-06, Revision 2, "Diverse and Flexible Coping Strategies (FLEX) Implementation Guide, December 2015 (ML 16005A625)

2. U.S. Nuclear Regulatory Commission (NRC), JLD-ISG-2012-01, Revision 1, "Compliance with Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigating Strategies for Beyond-Design-Basis External Events", January 22, 2016(ML15357A163)

3. Luminant Letter logged TXX-14037 from R. Flores to the NRC dated March 27, 2014, Seismic Hazard and Screening Report (CEUS Sites), Response to NRC Request for Information Pursuant to 10 CFR 50.54(£) Regarding Recommendation 2.1 (ML14099A197)

4. NRC Letter from F. Vega to Rafael Flores (Luminant) dated January 22, 2016, "Comanche Peak Nuclear Power Plant, Units 1 and 2 -Staff Assessment of Information Provided Pursuant to Title 10 of the Code of Federal Regulations Part 50, Section 50.54(£), Seismic Hazard Reevaluations For Recommendation 2.1 Of the Term Task Force Review Of Insights From The Fukushima Dai-Ichi Accident And Staff Closure Of Activities Associated With Recommendation 2.1, "Seismic" (CAC NOS. MF3937 and MF3938)" (ML16014A125)

Dear Sir or Madam:

The purpose of this letter is to provide the results of the assessment by Vistra Operations Company LLC ("Vistra OpCo") for Comanche Peak Nuclear Power Plant Units 1and2 (CPNPP) to determine if the FLEX strategies developed, implemented and maintained in accordance with NRC Order EA-12-049 can be implemented considering the impacts of the reevaluated seismic hazard. The assessment was performed in accordance with the guidance provided in Appendix H of NEI 12-06, Revision 2 (Reference

1) which was endorsed by the NRC (Reference 2). )-/ 5 / fJ/vt 5 5 z._(p ;V /( ;vfvf 5 5 U. S. Nuclear Regulatory Commission TXX-17009 Page 2 of 2 01126/2017 The Mitigating Strategies Seismic Hazard Information (MSSHI) is CPNPP's reevaluated seismic hazard information developed using Probabilistic Seismic Hazard Analysis (PSHA). The MSSHI includes a performance-based Ground Motion Response Spectrum (GMRS), Uniform Hazard Response Spectra (UHRS) at various annual probabilities of exceedance, and a family of seismic hazard curves at various frequencies and fractiles developed at the CPNPP control point elevation.

Vistra OpCo submitted the reevaluated seismic hazard information including the UHRS, GMRS and the hazard curves to the NRC on March 27, 2014 (Reference 3). The NRC staff concluded that the GMRS that was submitted adequately characterizes the reevaluated seismic hazard for the CPNPP site (Reference 4). Consistent with H.4.1 of Reference 1, the CPNPP GMRS is bounded by the Safe Shutdown Earthquake (SSE) spectrum at frequencies 1 Hz and greater. The FLEX strategies were developed in consideration of the Current Licensing Basis SSE. Therefore, the FLEX strategies for CPNPP can be implemented as designed and no further seismic evaluations are necessary as noted in the NRC Staff Closure letter for CPNPP (Reference 4). This letter contains no new regulatory commitments and no revision to existing regulatory commitments.

If you have any questions regarding this submittal, please contact Carl B. Corbin at (254) 897-0121 or carl.corbin@luminant.com.

I state under penalty of perjury that the foregoing is true and correct. Executed oriJanuary 26, 2017. c-Kriss Kennedy, Region IV Gregory T. Bowman, NRR Margaret M. Watford, NRR Resident Inspectors, Comanche Peak Sincerely, Vistra Operations Company LLC Tho:::Jft:

Site Vice President