ML12276A265

09/20/12 Meeting Summary with Wolf Creek Nuclear Operating Corporation to Discuss Transition from Current to NRC-Approved Westinghouse Methodologies for Performing the Core Design and Non-LOCA Safety Analysis at Wolf Creek

ML12276A265
Person / Time
Site:	Wolf Creek
Issue date:	11/01/2012
From:	Brian Benney Plant Licensing Branch IV
To:	Office of Nuclear Reactor Regulation
Benney B
References
TAC ME9495
Download: ML12276A265 (5)

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• • • • 1' " 0' LICENSEE: Wolf Creek Nuclear Operating Corporation FACILITY: Wolf Creek Generating Station

SUMMARY

OF SEPTEMBER 20,2012, CATEGORY 1 MEETING TO DISCUSS LICENSEE'S PLANS TO TRANSITION FROM CURRENT METHODOLOGIES TO NRC-APPROVED WESTINGHOUSE METHODOLOGIES FOR PERFORMING THE CORE DESIGN AND THE NON-LOSS-OF-COOLANT ACCIDENT SAFETY ANALYSES AT WOLF CREEK (TAC NO. ME9495)

On September 20,2012, a public meeting was held between the U.S. Nuclear Regulatory Commission (NRC), and representatives of Wolf Creek Nuclear Operating Corporation (WCNOC, the licensee), at NRC Headquarters, One White Flint North, 11555 Rockville Pike, Rockville, Maryland. The purpose of the meeting was to discuss changes to the Wolf Creek Generating Station (WCGS) post-fire safe shutdown analysis methods.

A list of meeting attendees is enclosed. Also, the licensee's slides presented at the meeting are located in the Agencywide Documents Access and Management System (ADAMS) at Accession No. ML12263A362.

The licensee presented information on how it would formulate its license amendment request (LAR) regarding a transition from its current methodologies (developed by WCNOC) to the NRC-approved Westinghouse Electric Company LLC (Westinghouse) methodologies for performing the core design and the non-Ioss-of-coolant accident (non-LOCA) safety analyses.

The licensee described how the proposed LAR would revise the WCGS licensing basis by adopting the Alternative Source Term (AST) radiological dose consequence analysis methodology in accordance with Section 50.67, "Accident source term," of Title 10 of the Code of Federal Regulations (10 CFR) for the design-basis accident (DBA) radiological dose consequence analyses. The licensee stated that the LAR would include a full-scope implementation of the AST, as described in NRC Regulatory Guide 1.183, Revision 0, "Alternative Radiological Source Terms for Evaluating Design Basis Accidents at Nuclear Power Reactors," July 2000 (ADAMS Accession No. ML003716792). Full-scope implementation of the AST impacts the LOCA, Fuel Handling Accident (FHA), Main Steam Line Break (MSLB), Steam Generator Tube Rupture (SGTR), Control Rod Ejection Accident (CREA), and Locked Rotor Accident (LRA) analyses. The LAR would include a separate enclosure for the AST to support the NRC staff's review of the request to implement the AST.

The Reactor Trip System (RTS), Engineered Safety Features Actuation System (ESFAS), and Loss of Power Diesel Generator Start (LOP DG Start) Instrument uncertainty analyses and setpoints would be performed consistent with the current Westinghouse setpoint methodology, as it applies to WCGS. The LAR would include an enclosure that contains the plant-specific setpoint methodology for the uncertainty analyses and set points. Changes to the RTS, ESFAS, and LOP DG Start Instrumentation Technical Specifications will include the adoption of

- 2 Technical Specifications Task Force (TSTF)-493, Revision 4, "Clarify Application of Setpoint Methodology for LSSS Functions."

WCNOC discussed its working relationship with Westinghouse for this future submittal. The NRC staff expressed an interest in learning more about the arrangement, as the arrangement appeared rather unique. In addition, the staff provided feedback and discussed lessons learned in a number of areas. General feedback included licensee oversight of vendor-produced documents, in particular, Quality Assurance and audit trails. The NRC staff cautioned the licensee regarding the use or limitations of "NRC-approved" documents, and strict accounting to ensure the analysis bounds the current power level. The NRC staff suggested that the licensee provide a roadmap that clearly describes to the staff which code is used to analyze each postulated accident. The staff also mentioned that detailed plant drawings that show potential release pOints or penetrations to the control room, as well as explanations for unusual meteorological data, are extremely helpful.

The NRC staff questioned whether or not WCNOC and Westinghouse had considered the inadvertent opening of a pressurizer pilot-operated relief valve (PORV) as a mass addition event, as well as a departure from nucleate boiling (DNB) event. The reactor coolant system depressurization leads to a low-pressure safety injection actuation. If the operator does not close the PORV, the continuing depressurization increases the safety injection delivery rate.

The pressurizer could fill very rapidly. This issue was noted to have been discussed recently during the extended power uprate reviews for St. Lucie Plant, Unit Nos. 1 and 2, and Turkey Point Nuclear Plant, Units 3 and 4.

Also discussed during the meeting was the NRC staff's drafting of a Notice of Availability (NOA) providing its guidance regarding an acceptable approach for a licensee who plans to adopt TSTF-493, Option B. to meet the staff's acceptance review criteria. This NOA is planned for completion before December 31,2012.

On June 13, 2012, the NRC staff met with Pacific Gas and Electric (PG&E). the licensee for Diablo Canyon Power Plant, Units 1 and 2 (DCPP), who indicated that it planned to have Westinghouse prepare detailed setpoint calculations for each limiting safety system setting affected by its digital safety system upgrade project currently being evaluated by the NRC staff .

The DCPP meeting summary, dated June 27,2012, is available in ADAMS at Accession No. ML12170A866. During the DCPP meeting, the NRC staff informed PG&E that its expectation was for the licensee to submit such setpoint calculation material on the docket. The representative for Westinghouse at the DCPP meeting stated that it was not Westinghouse's intent to submit the calculations on the docket, but merely to make them available for viewing to the NRC staff at the Westinghouse offices in Rockville, Maryland. The NRC staff informed the DCPP licensee that this practice was unacceptable, and that any safety conclusions reached by the staff must be based on docketed material. During the meeting on September 20, 2012, the NRC advised WCNOC that the practice of submitting calculation materials on the docket was the expectation for WCGS as well.

The NRC's Instrumentation and Controls staff representative stated that to better manage the review; it would likely have two separate reviewers participate in the WCGS submittal when the submittal comes in next year. One reviewer would perform a technical analysis of the setpoint calculation methodology, and a second reviewer would evaluated the licensee's proposed

- 3 Setpoint Control Program methodology for compliance with the NRC staffs guidance to be published in the NOA for TSTF-493, Option B, described above.

The NRC staff questioned the aggressiveness of the proposed schedule as well as the combination of the new code, the AST, and the Option B. At the end of the meeting, the staff expressed appreciation to the licensee for taking the time to hold a pre-licensing meeting to discuss issues that may arise during the review. The NRC staff offered to meet again to discuss the planned submittal.

As a Category 1 meeting, the public was invited to observe and was given opportunities to communicate with the NRC after the business portion, but before the meeting was adjourned.

Public Meeting Feedback forms were not received.

Please direct any inquiries to me at (301) 415-2767 or via e-mail Brian.Benney@nrc.gov.

Brian Benney, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-482

Enclosure:

List of Attendees cc w/encl: Distribution via Listserv

LIST OF ATTENDEES AND BRIDGE LINE PARTICIPANTS SEPTEMBER 20.2012. MEETING U.S. NUCLEAR REGULATORY COMMISSION WOLF CREEK NUCLEAR OPERATING CORPORATION U.S. Nuclear Regulatory Commission Brian Benney - Office of Nuclear Reactor Regulation (NRR)

David Rahn - NRR Pong Chung - NRR Kristy Bucholtz - NRR William Kemper - NRR Sam Miranda - NRR Tony Mendiola - NRR Louis Dumont - Region II Chris Jackson - NRR Travis Tate - NRR Licensee and its Representatives John Broschak - Wolf Creek Nuclear Operating Corporation (WCNOC)

Pete Kennamore - WCNOC Steve Wideman - WCNOC Kevin Roland - Westinghouse Electric Company LLC (Westinghouse)

James Boatwright - Westinghouse Jim Andrachek - Westinghouse Terry Williams - Westinghouse (phone)

Sean Kinnas - Westinghouse (phone)

Jorge Fontes - Westinghouse (phone)

Monica Angoff - Westinghouse (phone)

Jeff Blair - WCNOC (phone)

Melanie Fici - Westinghouse (phone)

Enclosure

Setpoint Control Program methodology for compliance with the NRC staffs guidance to be published in the NOA for TSTF-493, Option B, described above.

The NRC staff questioned the aggressiveness of the proposed schedule as well as the combination of the new code, the AST, and the Option B. At the end of the meeting, the staff expressed appreciation to the licensee for taking the time to hold a pre-licensing meeting to discuss issues that may arise during the review. The NRC staff offered to meet again to discuss the planned submittal.

As a Category 1 meeting, the public was invited to observe and was given opportunities to communicate with the NRC after the business portion, but before the meeting was adjourned.

Public Meeting Feedback forms were not received.

Please direct any inquiries to me at (301) 415-2767 or via e-mail Brian.Benney@nrc.gov.

IRA by KKalyanam fori Brian Benney, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-482

Enclosure:

List of Attendees cc w/encl: Distribution via Listserv DISTRIBUTION:

PUBLIC RidsNrrPMWolfCreek Resource LPLIV r/f RidsOgcRp Resource RidsAcrsAcnw_MailCTR Resource RidsRgn4MailCenter Resource RidsNrrDeEicb Resource SKennedy, EDO RIV RidsNrrDorl Resource TWertz, NRR RidsNrrDorlLpl4 Resource DRahn, NRR/DE/EICB RidsNrrDraAadb Resource KBuckholtz, NRR/DSS/STSB RidsNrrDssSnpb Resource PChung, NRR/DE/EICB RidsNrrDssSrxb Resource WKemper, NRR/DE/EICB RidsNrrDssStsb Resource SMiranda, NRR/DSS/SRXB RidsNrrLAJBurkhardt Resource LDumont, RII ADAMS Accession Nos. Meeting Notice ML12249A029, Meetlng S ummary ML12276A265 *via . e-mal" iOFFICE NRRlDORULPL4/PM NRRlDORULPL4/LA NRR/DE/EICB/BC NRRlDRAlAADB/BC NRRlDSS/SNPB/BC !

!NAME BBenney JBurkhardt JThorp* TTate AMendiola DATE 10/5/12 10/4/12 1015/12 10/17/12 10/17/12 I

• OFFICE NRRlDSS/SRXB/BC NRR/DSS/STSB/BC NRRlDORULPL4/BC NRRlDORULPL4/PM BBenney I NAME CJackson RElliott* MMarkley (KKalyanam for) i DATE 10/18/12 10/5/12 1111/12 1111112 OFFICIAL RECORD COpy