ML23212A944

Post Accident Monitoring Report

ML23212A944
Person / Time
Site:	North Anna
Issue date:	07/11/2023
From:	Hilbert L Virginia Electric & Power Co (VEPCO)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
SSD 23-187
Download: ML23212A944 (1)

Text

• f- .----- ..'

VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 July 11, 2023 U.S. Nuclear Regulatory Commission Serial No.23-187 Attention: Document Control Desk NAPS: RAP Washington, D.C. 20555 Docket No. 50-338 License No. NPF-4 VIRGINIA ELECTRIC AND POWER COMPANY (DOMINION ENERGY VIRGINIA)

NORTH ANNA POWER STATION UNIT 1 POST ACCIDENT MONITORING (PAM) REPORT On May 31, 2023, with Unit 1 in Mode 1, the "A" Main Steam Trip Valve position switch, 1-MS-TV-101A-IBISSW-33-2, roller bearing was identified as being loose and out of place. Following a walkdown by maintenance personnel, the roller retainer was noted as being failed and not retaining the roller. This issue can be corrected by replacing the limit switch arm; however, the limit switch arm replacement would introduce a high probability of actuating the limit switch. If this were to occur, the main steam trip valve would close.

and could cause a transient up to and including a reactor trip and a safety injection unnecessarily. The associated repairs will occur during the nearest outage of sufficient .

duration. Technical Specification (TS) 3.3.3 Condition A requires restoration of the valve position indication to operable within thirty days. Since the valve position indication was not returned to service within thirty days, a Post Accident Monitoring Report is required in accordance with TS 5.6.6. This letter provides the required report including our plan and schedule for restoring the valve position indication to service. Continued operation with the valve position indication inoperable is permitted because there are two trains of valve position indication, and_ the other train remains operable.

• This report has been reviewed and approved by the Facility Safety Review Committee.

If you have any questions or require additional information, please contact Mr. Marcus Hofmann (540) 894-21.00.

Sincerely, ,.

i ~1------f~ L. ~,*t:~'itir (L

Lisa Hilbert Site Vice President Commitments made ir')this letter: Repair and restoration to operability for 01-MS-TV-

• , 101A-IBISSW-33-2 during the nearest outage of sufficient duration. **

L_

Serial No.23-187 Docket No. 50-338 PAM Report Page 2 of 2 cc: U.S. Nuclear Regulatory Commission Region II .

. Marquis One Tower 245 Peachtree Center Ave., NE, Suite 1200

• Atlanta, Georgia 30303-1257 NRC Senior Resident Inspector North Anna Power Station Mr. G. E. Miller NRC Senior Project Manager U.S. Nuclear Regulatory Commission One White Flint North Mail Stop 09 E-3 11555 Rockville Pike Rockville, Maryland 20852-2738