ML22119A172

Post-Accident Monitoring (PAM) Report

ML22119A172
Person / Time
Site:	North Anna
Issue date:	04/13/2022
From:	Hilbert L Virginia Electric & Power Co (VEPCO)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
22-118
Download: ML22119A172 (3)

Text

VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 April 13, 2022 U.S. Nuclear Regulatory Commission Serial No.22-118 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 March 6, 2022, with Unit 1 in Mode 1, the Channel 1 Wide Range Ex-Core Neutron Monitor, 01-NM-NFl-190~ 1, was found failed high, indicating 200% .. There was also a loss of trending noted on the Plant Computer System (PCS) and the indication on the Remote Monitoring Panel, 01-NM-NFl-190B2, located in the Fuel Building was also at 200%.

The cause of the inoperable neutron monitor is currently unknown. Troubleshooting to determine the cause of the failure will occur after the Unit 2 refueling outage has been completed and resources become available to support the effort. The associated repairs will occur at the nearest maintenance* opportunity. Technical Specification (TS) 3.3.3 Condition A requires restoration of the neutron monitor to operable within thirty days. If the neutron monitor is 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 neutron monitor to service.

Continued operation w,ith the neutron monitor inoperable is permitted because there is another train of wide range neutron monitoring that is operable. Both trains of the source range neutron monitors are operable if they become necessary. Additionally, the normal power range nuclear instruments (PRNI) are operable to provide power indication during normal plant operation:,*

• This report has been r~viewed and approved by the Facility Safety Review Committee.

If you have any quest.ions or require additional information, please contact Mr. Marcus Hofmann (540) 894-2190.

Serial No.22-118 Docket No. 50-338 PAM Report Page 2 of 3 Sincerely, Lisa Hilbert Site Vice President Commitments made in this letter: Repair and restoration to operability for 01-NM-NFl-190B1 at the nearest maintenance opportunity.

Serial No.22-118 Docket No. 50-338 PAM Report Page 3 of 3 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 0-8 G9A 11555. Rockville Pike Rockville, Maryland 20852-2738