ML25351A278
| ML25351A278 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 12/17/2025 |
| From: | Joel Jenkins Dominion Energy, Dominion Energy Virginia, Virginia Electric & Power Co (VEPCO) |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| 25-298 | |
| Download: ML25351A278 (0) | |
Text
Dominion Energy Virginia North Anna Power Station 1022 Haley Drive, Mineral, VA 23117 Dominion Energy.com December 17, 2025 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555 Serial No.
NAPS:
Docket No.
License No.25-298 RAP 50-338 NPF-4 VIRGINIA ELECTRIC AND POWER COMPANY (DOMINION ENERGY VIRGINIA)
NORTH ANNA POWER STATION UNIT 1 POST ACCIDENT MONITORING (PAM) REPORT On November 9, 2025, with Unit 1 in Mode 1, the open indication light for the Phase B containment isolation valve (CIV) 1-CC-TV-102C (B" RCP CC Return Outside Isolation Valve) was determined to be inoperable. This Regulatory Guide 1.97 CIV is located outside of containment in the component cooling (CC) water return line from the "B" reactor coolant pump (RCP). The cause of the inoperable open light is a failed bulb.
Technical Specification (TS) 3.3.3 Condition A requires restoration of the CIV indication to operable within thirty days. If CIV indication 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 and includes our plan and schedule for restoring the CIV indication to service.
This is a valve position open indication operability issue only. The replacement of the bulb with the unit on-line can lead to grounding of the circuit due to possible separation of the bulb glass from its base. This could possibly result in the associated trip valve closing which would be detrimental to Unit 1 operation. Therefore, due to the inherent risks involved with performing maintenance on-line, repairs are scheduled to be performed at the first entry into a unit condition of sufficient duration to allow the repair. The risks associated with performing repairs on-line include maintenance in a sensitive area (i.e.,
Control Room Safeguards Equipment Panel) and by-passing the air supply to prevent the CIV from inadvertently closing, which may require manually tripping the reactor and shutting down the running "B" RCP.
Continued operation with this valve open indication inoperable is permitted because there are several levels of alternate indication. The Plant Computer System (PCS) provides an alternate reliable indication (PCS computer point S1 CC017D, "B" RCP CC Return Outside Isolation Valve) to determine valve position. Flow indicators will also indicate zero flow for various "B" RCP parameters when 1-CC-TV-102C is closed. The closed light indication is operable. In addition, 1-CC-TV-102D ("B" RCP CC Return Inside Isolation Valve) is operable.
Serial No.25-298 Docket No. 50-338 PAM Report Page 2 of 2 Both inside and outside CIVs cycled properly during their last valve position indication tests completed on October 9, 2025. If a containment depressurization actuation (CDA) were to occur, the CIV would receive a signal to close.
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. Matt Hayes (540) 894-2100.
Sincerely, ;(~~
- v/A--r-r ;.le W -;; IZ-CZ-FS, h/C_ JA-~e S James Jenkins Site Vice President Commitments made in this letter
- Replacement of the open indication light for 1-CC-TV-102C during the next entry into a unit condition of sufficient duration to allow the repair.
cc:
J. Lara - NRG Region II Administrator G.E. Miller - NRG Senior Project Manager NRG Senior Resident Inspector - North Anna Power Station