ML26089A113
| ML26089A113 | |
| Person / Time | |
|---|---|
| Site: | Summer  (NPF-012) |
| Issue date: | 03/29/2026 |
| From: | Carr E Dominion Energy South Carolina |
| To: | NRC/RGN-II, Document Control Desk |
| References | |
| 26-048C | |
| Download: ML26089A113 (0) | |
Text
Dominion Energy South Carolina, Inc Virgil C. Summer Nuclear Station Bradham Boulevard & Highway 215, Jenkinsville, SC 29065 Mailing Address:
P.O. Box 88, Jenkinsville, SC 29065 DominionEnergy.com By letter dated March 2, 2026 (Reference 1), the Nuclear Regulatory Commission (NRC) notified Dominion Energy South Carolina (DESC) of the final significance determination of a White Finding and Notice of Violation (NOV)05000395/2025003-01.
The purpose of this letter is to provide the required written response to the NOV, pursuant to 10 CFR 2.201. Attachment 1 provides the reason for the violation, corrective steps taken and results achieved, corrective steps that will be taken, and the date when full compliance was achieved.
Should you have any questions regarding this response or require additional information, please contact Mr. Michael Moore, Manager Nuclear Emergency Preparedness and Licensing at (803) 345-4752.
Sincerely, Eric S. Carr Chief Nuclear Officer, President Nuclear Operations and Contracted Energy Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555 Serial No.: 26-048C VCS-LIC/JB R0 Docket No. 50-395 License No. NPF-12 DOMINION ENERGY SOUTH CAROLINA (DESC)
VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT 1 REPLY TO A NOTICE OF VIOLATION; EAF-RII-2025-0235 March 29, 2026
Serial No. 26-048C Reply to a Notice of Violation; EAF-RII-2025-0235 Page 2 of 2
References:
- 1. Letter from Julio F. Lara (NRC) to Eric S. Carr (DESC), Virgil C. Summer-Final Significance Determination of a White Finding and Notice of Violation and Assessment Follow-up Letter; NRC Inspection Report 05000395/2026091, dated March 2, 2026. (ADAMS Accession No. ML26054A271)
Attachment:
- 1. Reply to a Notice of Violation; EAF-RII-2025-0235 Commitments contained in this letter: None cc:
G. J. Lindamood - Santee Cooper J. F. Lara - NRC Region II M. Fannon - NRC Region II G. E. Miller - NRC Project Mgr.
NRC Resident Inspector
REPLY TO A NOTICE OF VIOLATION; EAF-RII-2025-0235 Dominion Energy South Carolina Virgil C. Summer Nuclear Station Unit 1
Serial No. 26-048C Page 1 of 2 REPLY TO A NOTICE OF VIOLATION; EAF-RII-2025-0235 Reason for the Violation VCSNS failed to implement a preventive maintenance procedure to ensure the reliability of the overspeed trip device for the turbine-driven emergency feedwater pump (TDEFP),
which resulted in the inoperability and unplanned unavailability of the pump. During surveillance testing on August 19, 2025, the TDEFP tripped due to the overspeed trip assembly not being properly engaged. The tappet nut was worn, which resulted in inadequate engagement with the emergency head lever, allowing an inadvertent overspeed trip.
Corrective Steps That Have Been Taken and the Results Achieved The TDEFP overspeed trip assembly was repaired to restore the TDEFP to operable status on August 21, 2025.
A root cause evaluation determined that the recurring TDEFP overhaul preventative maintenance task did not direct performance of the inspection and refurbishment of the overspeed trip assembly. The overspeed trip assembly was replaced in February 2026, establishing a new baseline for preventative maintenance. A design modification was implemented in March to improve performance monitoring capabilities during surveillance testing.
A recurring preventative maintenance task to replace key overspeed trip assembly components was established to eliminate the potential for unknown wear or other factors that could lead to inadvertent TDEFP overspeed trip actuations.
Corrective Steps That Will be Taken MMP-300.015, Turbine Maintenance, Emergency Feedwater Pump TPP0008, Section 7.8 is being revised to incorporate industry best practices, based on EPRI guidance, for overspeed trip assembly service inspection. It will require the TDEFP overspeed trip assembly to be inspected periodically for worn components and refurbished, as necessary. This includes cleaning and inspecting the tappet nut and verifying adequate engagement dimensions. New overspeed trip assembly components were installed in February 2026, and improved performance monitoring capabilities were implemented in March.
Serial No. 26-048C Page 2 of 2 Date When Full Compliance Will be Achieved Regulatory compliance was restored on August 21, 2025, when the overspeed trip assembly was repaired under corrective maintenance and equipment operability was achieved. Preventative maintenance was performed in February 2026, and actions to prevent reoccurrence were implemented when the reoccurring maintenance task was established.