ML22115A072

Supplement to Annual Changes, Tests, and Experiments Report Regulatory Commitment Evaluation Report

ML22115A072
Person / Time
Site:	Surry
Issue date:	04/22/2022
From:	Henderson J Virginia Electric & Power Co (VEPCO)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
22-058A
Download: ML22115A072 (2)

Text

VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 APR 2 2 W22 U.S. Nuclear Regulatory Commission Serial No. 22-058A Attn: Document Control Desk SPS/MMT RO Washington, DC 20555-0001 Docket Nos. 50-280 50-281 License Nos. DPR-32 DPR-37 VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNITS 1 AND 2 SUPPLEMENT TO ANNUAL CHANGES, TESTS, AND EXPERIMENTS REPORT REGULATORY COMMITMENT EVALUATION REPORT Virginia Electric and Power Company hereby submits the annual report of Changes, Tests, and Experiments pursuant to 10 CFR 50.59(d)(2) implemented at Surry Power Station. The Attachment provides the descriptions and summaries of the Regulatory Evaluations and the Regulatory Commitment Change Evaluation completed in 2021. Upon further review, it has been recognized that a Regulatory Commitment Change Evaluation was not included in the report. This supplement to the annual report provides a summary of the Regulatory Commitment Change Evaluation in Attachment 1.

Should you have any questions regarding this report, please contact Michael M. True, Jr. at (757) 365-2446.

Jo n ...._.._,,,,...., erson Director Nuclear Safety & Licensing Surry Power Station - Regulatory Commitment Change Evaluation Commitments made in this letter: None cc: United States Nuclear Regulatory Commission, Region II Marquis One Tower, Suite 1200 245 Peachtree Center Avenue, NE Atlanta, Georgia 30303-1257 NRC Senior Resident Inspector Surry Power Station

Serial No. 22-058A 10 CFR 50.59 Annual Report Page 2 of 2 Attachment 1 Surry Units 1 & 2 Regulatory Commitment Change Evaluation for 2021 Commitment Change Evaluation Summary 10/28/2021 Original Commitment Summary:

In response to NRC Bulletin 88-09 dated October 7, 1988, Dominion established a program to inspect each reactor thimble tubes every other operational cycle (in letter Serial No. 88-515C, dated July 8, 1991).

Revised Commitment Summary:

Extend the flux thimble tubes eddy current inspections frequency from every other operational cycle to every fourth operational cycle.

Justification:

The amount of thimble tube degradation identified over the years for Unit 1 and Unit 2 is minor.

There has not been a trend associated with any degradation. The Surry thimble tubes design is a double wall versus a single wall. The double wall thimble tube design itself provides an added level of protection in that both walls must be breeched prior to leakage. Therefore, it is acceptable to extend the flux thimble tubes eddy current inspections frequency from every other operational cycle to every fourth operational cycle.

It is noted that in the original commitment made to NRC by Letter Serial No. 88-515C stated the following: "this inspection frequency is subject to change based on accumulation of data or evidence of wear on inner tube". The letter also states that "The inner tube can lose 60% of its wall thickness without exceeding ASME Code material allowable under design conditions. This thimble tube wear limit was determined using finite element structural analysis under the assumption that the outer tube would be completely worn through. The inner tube wear limit of 60% is also identified in Westinghouse WCAP-12292.