ML19141A194

Regulatory Audit Summary Regarding Request to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors

ML19141A194
Person / Time
Site:	Calvert Cliffs
Issue date:	05/30/2019
From:	Marshall M Plant Licensing Branch 1
To:	Bryan Hanson Exelon Generation Co, Exelon Nuclear
Marshall M, NRR/DORL/LPLI, 415-2871
References
EPID L-2018-LLA-0482
Download: ML19141A194 (7)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 Ma. y 30 , 2 i) 1 9 Mr. Bryan C. Hanson Senior Vice President Exelon Generation Company, LLC President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

CALVERT CLIFFS NUCLEAR POWER PLANT, UNITS 1 AND 2-REGULATORY AUDIT

SUMMARY

REGARDING REQUEST TO ADOPT 10 CFR 50.69, "RISK-INFORMED CATEGORIZATION AND TREATMENT OF STRUCTURES, SYSTEMS AND COMPONENTS FOR NUCLEAR POWER REACTORS" (EPID L-2018-LLA-0482)

Dear Mr. Hanson:

By letter dated November 28, 2018 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML18333A022), as supplemented by letters dated November 29, 2018, and May 10, 2019 (ADAMS Accession Nos. ML18337A038 and ML19130A180, respectively), Exelon Generation Company, LLC (the licensee) submitted a license amendment request regarding Calvert Cliffs Nuclear Power Plant, Units 1 and 2. The proposed amendment would modify the licensing basis to allow for the implementation of the provisions of Title 10 of the Code of Federal Regulations (10 CFR) Part 50.69, "Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors."

The proposed amendments would include an exception to the U.S. Nuclear Regulatory Commission (NRC)-endorsed categorization process in Nuclear Energy Institute 00-04, Revision 0, "10 CFR 50.69 SSC [Structures, Systems and Components] Categorization Guideline," dated July 2005 (ADAMS Accession No. ML052910035), to apply an alternative approach for the seismic hazard specified in Electric Power Research Institute Report 3002012988, "Alternative Approaches for Addressing Seismic Risk in 10 CFR 50.69 Risk-Informed Categorization," dated July 2018. 1 The NRC staff conducted a regulatory audit to support the review of the license amendment request. The purpose of the audit was to gain a more detailed understanding of the basis and implementation of the licensee's alternate seismic approach in its proposed categorization. A summary of the regulatory audit is enclosed with this letter.

1 A copy of Report 3002012988 is available online at https://www.epri.com/#/pages/product/000000003002012988/.

B. Hanson If you have any questions, please contact me at (301) 415-2871 or Michael.Marshall@nrc.gov.

Sincerely, Michael L. Marshall, Jr., Senior Project Manager Plant Licensing Branch I Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-317 and 50-318

Enclosure:

Summary of Regulatory Audit cc: Listserv

SUMMARY

OF REGULATORY AUDIT BY THE OFFICE OF NUCLEAR REACTOR REGULATION REGARDING LICENSE AMENDMENT REQUEST TO ADOPT RISK-INFORMED CATEGORIZATION EXELON GENERATION COMPANY, LLC CALVERT CLIFFS NUCLEAR POWER PLANT, UNITS 1 AND 2 DOCKET NOS. 50-317 AND 50-318

1.0 INTRODUCTION

By letter dated November 28, 2018 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML18333A022), as supplemented by letters dated November 29, 2018, and May 10, 2019 (ADAMS Accession Nos. ML18337A038 and ML19130A180, respectively), Exelon Generation Company, LLC (Exelon, the licensee) submitted a license amendment request regarding Calvert Cliffs Nuclear Power Plant, Units 1 and 2 (Calvert Cliffs).

The proposed amendments would modify the licensing basis to allow for the implementation of the provisions of Title 10 of the Code of Federal Regulations ( 10 CFR) Part 50.69, "Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors." The proposed amendments include an exception to the U.S. Nuclear Regulatory Commission (NRC)-endorsed categorization process in Nuclear Energy Institute (NEI) 00-04, Revision 0, "10 CFR 50.69 SSC [Structures, Systems and Components]

Categorization Guideline," dated July 2005 (ADAMS Accession No. ML052910035), to apply an alternative seismic approach for the seismic hazard specified in Electric Power Research Institute (EPRI) Report 3002012988, "Alternative Approaches for Addressing Seismic Risk in 10 CFR 50.69 Risk-Informed Categorization," dated July 2018. 1 2.0 AUDIT LOCATION AND DATES The NRC staff conducted the regulatory audit on March 26, 2019 - March 28, 2019, at the Exelon offices in Kennett Square, Pennsylvania. The audit plan is available in ADAMS at Accession No. ML19065A044. This audit was limited to the alternate seismic approach described in the license amendment request.

3.0 AUDIT TEAM MEMBERS

• Michael Marshall, Project Manager, NRC

• Mehdi Reisi-Fard, Team Leader, Probabilistic Risk Assessment (PRA), NRC

• Shilp Vasavada, Reliability and Risk Analyst, PRA, NRC

• David Heeszel, Geophysicist, NRC (participation by telephone) 1A copy of Report 3002012988 is available online at https://www.epri.com/#/pages/product/000000003002012988/.

Enclosure

4.0 LICENSEE STAFF AND OTHERS THAT PARTICIPATED IN SUBSTANTIVE DISCUSSIONS Some of the participants below participated in the audit by telephone.

Exelon and Its Contractors

• Enrique Villar (Exelon)

• Jeffery Stone (Exelon)

• Philip Tarpinian (Exelon)

• Shannon Rafferty-Czincila (Exelon)

• James Landale (Exelon)

• Gene Kelly (Exelon)

• Preeti Furtado (Exelon)

• Charlotte Geiger (Exelon)

• Barry Sloane (Jensen Hughes)

• Lawrence Lee (Jensen Hughes)

• Charles Young (Jensen Hughes)

• Brian Albinson (Jensen Hughes)

• Nicholas Lovelace (Jensen Hughes)

Other Industry Participants

• John Richards (Electric Power Research Institute)

• Patrick O'Regan (Electric Power Research Institute)

• Gregory Hardy (Simpson, Gumpertz & Heger)

• Steve Kimbrough (Duke Energy)

• Heather Szews (Duke Energy)

• Thomas Jones (Dominion Energy)

• William Webster (Dominion Energy)

• Gregory Krueger (NEI)

• Partha Chandran (Southern Nuclear Company)

• Jacob Johnson (Tennessee Valley Authority) 5.0 LIST OF DOCUMENTS The NRC staff had access to documents requested in the audit plan via an electronic document reading room established by the licensee. The following documents were available in the electronic document reading room:

• A listing of SSCs identified as low saf~ty significant based on the corresponding internal events and fire PRAs that either have a design-basis function during seismic events or functions credited for mitigation and prevention of severe accidents caused by seismic events for each of Plants A through D in the EPRI report

• Seismic Walkdown Report for Calvert Cliffs in response to Near-Term Task Force Recommendation 2.3

• Calvert Cliffs Individual Plant Examination of External Events submittal

The NRC staff did not review any additional documents during the audit. Except for an audit agenda, the NRC staff did not remove any documents from the audit site or electronic document reading room .

6.0 DESCRIPTION

OF AUDIT ACTIVITIES During the audit, the NRC staff discussed each of the information needs in the audit plan with the licensee, as well as its support staff. The technical discussions were entirely related to the alternate seismic approach proposed by the licensee and its implementation in the categorization process. Specifically, the discussions were focused on:

• The inclusion of qualitative and/or quantitative consideration of seismic events as part of the categorization process in the proposed Calvert Cliffs alternate seismic approach, including specific areas of the categorization process for such inclus_ion

• The available information that can support the inclusion of qualitative and/or quantitative consideration of seismic events as part of the categorization process

• The technical acceptability of PRAs used for the case studies in the EPRI report

• The SSC 'mapping' between the different PRAs used for the _case studies in the EPRI report

• The insights from case studies performed in the EPRI report and their inclusion in the proposed Calvert Cliffs alternate seismic approach 7.0 AUDIT OBSERVATIONS No final licensing.conclusions or regulatory findings were made during the audit regarding the proposed license amendment request. The licensee was informed of _the following:

• This audit was very helpful in increasing the NRC staff's understanding of the alternate seismic approach process.

• The audit and review of the license amendment request is limited to the Tier 1 option described in the alternative seismic approach.

• The NRC staff does not plan to rely on Case Study B in making a regulatory decision on the Calvert Cliffs 50.69 license amendment request.

• The NRC staff is relying on information that has been provided on dockets for Case Studies A, C, and D. This information will need to be added to the Calvert Cliffs license amendment request.

o Use of and documentation of the use of docketed information for Case Studies A, C, and D will result in disclosing the names of Case Studies A, C, and D.

Potential Request for Additional Information The NRC staff informed the licensee that a request for additional information (RAI) will be issued, and the licensee will be expected to provide the requested information on the docket.

The NRC staff informed the licensee that the following information needs included in the audit plan may be issued to the licensee as part of an RAI: 1, 2, 3, 4, 6, 7, 9, 11 , 12, 13, and 14 (see the audit plan for a description of each of the information needs). For the potential RAls involving the case studies, the NRC staff indicated which of the potential RAls would apply to which case study.

During the audit, the licensee informed the NRC staff that it intended to supplement its application to address a subset of information needs (i.e., 1, 2, 3, 4, 6, and 7) in the audit plan.

Description of Open items The NRC staff informed the licensee that the license condition proposed by the licensee in the license amendment request may need to be revised because the proposed license condition does not account for the possibility of changing from Tier 1 described in EPRI Report 3002012988. The NRC staff informed the licensee that the audit team would need to consult with NRC staff not participating in the audit and consider the need to change the proposed license condition against the requirements in 10 CFR 50.69.

Deviations from the Audit Plan Based on the discussions during the audit, the NRC staff determined that the need for a second audit identified in the audit plan and scheduled between April 8, 2019, and April 12, 2019, was unnecessary.

ML19141A194 OFFICE DORL/LPL 1/PM DORL/LPL 1/LA DRA/APLB/TL DORL/LPL 1/BC DORL/LPL 1/PM NAME MMarshall LRonewicz MReisi-Fard JDanna MMarshall DATE 05/24/2019 05/22/2019 05/24/2019 05/24/2019 05/30/2019