RA-18-0252, Seismic Probabilistic Risk Assessment (Spra), Response to March 12, 2012 Request for Information Regarding Recommendation 2.1 Seismic of the Near-Term Task Force Related to the Fukushima Dai-ichi Nuclear Power Plant Accident

Seismic Probabilistic Risk Assessment (Spra), Response to March 12, 2012 Request for Information Regarding Recommendation 2.1 Seismic of the Near-Term Task Force Related to the Fukushima Dai-ichi Nuclear Power Plant Accident

ML19004A127
Person / Time
Site:	Oconee
Issue date:	12/21/2018
From:	Burchfield J Duke Energy Carolinas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
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ML19009A128	List: RA-18-0252, Seismic Probabilistic Risk Assessment (Spra), Response to March 12, 2012 Request for Information Regarding Recommendation 2.1 Seismic of the Near-Term Task Force Related to the Fukushima Dai-ichi Nuclear Power Plant Accident
References
RA-18-0252
Download: ML19004A127 (3)

Text

J. Ed Burchfield, Jr.

Vice President Oconee Nuclear Station Duke Energy ON01 VP I 7800 Rochester Hwy Seneca, SC 29672 o: 864.873.3478 f., 864.873.5791

_ Ed.Burchfield@duke-energy.com RA-18-0252 10 CFR 50.4 December 21, 2018 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Duke Energy Carolinas, LLC (Duke Energy)

Oconee Nuclear Station (ONS), Units 1, 2, and 3 Docket Numbers 50-269, 50-270, 50-287 Renewed License Numbers DPR-38, DPR-47, DPR-55'

Subject:

Oconee Nuclear Station Units 1, 2, and 3 - Seismic Probabilistic Risk Assessment (SPRA),

Response to March 12, 2012 Request for Information Regarding Recommendation 2.1 "Seismic" of the Near-Term Task Force Related to the Fukushima Dai-ichi Nuclear Power Plant Accident

References:

1. NRC Letter, Request for Information Pursuant to 10 CFR 50.54({) Regarding Recommendations 2.1, 2.3, and 9.3 of the Near-Term Task Force review of Insights from the Fukushima Dai-ichi Accident, dated March 12, 2012 (Mli.12053A340)

2. EPRI 1025287, Seismic Evaluation Guidance: Screening, Prioritization and Implementation Details (SPID) for the Resolution of Fukushima Near-Term Task Force Recommendation 2.1: Seismic, dated February, 2013 (ML12333A170)

3. Duke Energy Letter, Seismic Hazard and $creening Report (CEUS Sites), Response to NRC 10 CFR 50.54(() Request for Informf}tion Pursuant to Title 1 O of the Code of Federal Regulations 50.54({)

regarding Recommendations 2.1, 2.3, and 9.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated March 31, 2014 (ML14092A024)

4. NRC Letter, Oconee Nuclear Station, Units 1, 2, and 3 - StaffAssessment of Information provided Pursuant to Title 10 of the Code of Federal Regulations Part 50, Section 50.54({), Seismic Hazard Reevaluationsfor Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated July 22, 2015 (ML15201A008)

5. NRC Letter, Final Determination of Licensee Seismic Probabilistic RiskAssessments, dated October 27, 2015. ML15194A015

RA-18-0252 December 21, 2018 Ladies and Gentlemen, On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued a request for information pursuant to 1 O CFR 50.54(f) associated with the recommendations of the Fukushima Near-Term Task Force (NTTF)

(Reference 1). Enclosure 1 of Reference 1 requested each licensee to reevaluate the seismic hazards at their sites using present-day NRC requirements c:1nd guidance, and to identify actions taken or planned to address plant-specific vulnerabilities associated with the updated seismic hazards.

Reference 2 contains industry guidance developed by EPRI that provide the screening, prioritization and implementation details for the resolution of Fukushima Near-Term Task Force Recommendation 2.1:

Seismic. The SPID (Reference 2) was used to compare the reevaluated seismic hazard to the design basis hazard. The Oconee Nuclear Station (ONS) Units 1, 2, and 3 reevaluated seismic;: hazard (Reference 3) concluded that the ground motion response spectrum (GMRS) exceeded the design basis seismic response spectrum in the 1 to 10 Hz range, and therefore a seismic probabilistic risk assessment was required.

Reference 4 contains the NRC Staff Assessment of the ONS Units 1, 2, and 3 seismic hazard submittal that concluded the reevaluated seismic hazard prepared for ONS is suitable for other activities associa.ted with the NRC Near-Term Task Force Recommendation 2.1: Seismic.

Reference 5 contains the NRC letter "Final Determination of Licensee Seismic Probabilistic Risk

' Assessments." In that letter (Table 1 a - Recommendation 2.1 Seismic- Information Requests) the NRC instructed ONS Units 1, 2, and 3 to submit an SPRA by December 31, 2018.

• Enclosure 1 of this letter contains the ONS Units .1, 2, and 3 Seismic Probabilistic Risk Assessment (SPRA)

Summary Report which provides the information requested in Enclosure 1, Item (8) B. of Reference 1.

This letter contains no new Regulatory Commitments and no revision to existing Regulatory Commitments; however, it does contain a new planned action to provide an alternate letdown isolation method which will achieve a seismic Large Early Release Frequency value below lxl0-6/reactor-year based on sensitivity analysis.

Should you have any questions regarding this submittal, please contact Laura Todd with Oconee Regulatory Affairs at (86:4) 873-6774.

I declare* under penalty of perjury that the foregoing is true and correct. Executed on December 21st, '2018.

Sincerely, J. Ed Burchfield, Jr.

Vice President Oconee Nuclear Station

Enclosure:

Oconee Nuclear Station Units 1, 2, and 3 Seismic Probabilistic Risk Assessment in Response to S0.54(f) Letter Regarding NTTF 2.1 Seismic Summary Report Page2

RA-18-0252 December 21, 2018 ,,

cc w/enclosure:

Ms. Catherine Haney, Regional Administrator U.S. Nuclear Regulatory Commission - Region II Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, Georgia 30303-1257 Mr. Ho Nieh, Director, Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738 Ms. Audrey Klett, Project Manager (by electronic mail only)

Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Mail Stop 0-8G9A 11555 Rockville Pike Rockville, Maryland 20852 Mr. Eddy Crowe NRC Senior Resident Inspector Oconee Nuclear Station Page 3