NRC issues white safety finding to V.C. Summer
The Nuclear Regulatory Commission has upheld and finalized a “white” safety finding at V.C. Summer power plant in Jenkinsville, S.C., over the plant’s failure to properly preplan and perform maintenance on its turbine-driven emergency feedwater pump (TDEFW) governor valve linkage. The 966-MWe three-loop Westinghouse pressurized water reactor at Summer started commercial operation in 1982.
Under the NRC’s reactor oversight process, a white inspection finding reflects low-to-moderate safety significance. A white finding is the second-lowest in the four-color grading scale, with “green” being the lowest and “yellow” and “red” warranting greater scrutiny. A white finding may require additional NRC inspections.
The decision: An NRC inspection conducted from November 2025 through March 2026 found that the plant's licensee, Dominion Energy South Carolina, has failed since 2017 to preplan or perform preventive maintenance on the TDEFW governor valve linkage using written procedures, documented instructions, or drawings. In a final determination issued June 29, NRC Region II acting regional administrator Julio Lara said this failure to act ultimately affected the performance of the equipment.
The governor valve’s last maintenance was conducted in 2017, the determination said. Since then, the licensee did not schedule maintenance activities to implement procedures that could have identified any degradation of the governor valve linkage, such as excessive play or worn subcomponents.
“As a result, degradation of the governor valve linkage progressed over time and remained undetected until it caused sufficient binding to trigger an overspeed trip of the TDEFW pump during a surveillance test on November 12, 2025,” said the notice of violation, which was included in the final determination.
Background: The NRC submitted its preliminary white finding on March 31. On May 7, Dominion responded to the preliminary finding, arguing that the violation merited a green finding of very low safety significance. Dominion said the pump would have successfully performed its safety function and injected into the steam generators “due to steam generator injection conditions that are inherently less challenging to turbine initial speed control than surveillance test conditions.”
“DESC takes this matter seriously and has thoroughly evaluated the condition and are implementing corrective actions to prevent recurrence. Based on the supplemental information provided, DESC’s perspective is that the significance of the finding is low safety significance (GREEN),” Dominion’s letter to the NRC said.
Inspectors, however, stood by their original finding. And as a result, V.C. Summer will remain in the second column of the NRC’s action matrix: regulatory response; that status begins in the fourth quarter of 2025. The plant was already under the regulatory response column because the NRC had issued a white finding to the plant for the third quarter of 2025. The previous violation involved much of the same equipment, according to the records. In this finding, the NRC said the licensee had failed to establish preventive maintenance on the TDEFW pump’s overspeed trip device. The NRC successfully completed and exited the extra inspection for the previous violation in early June.
V.C. Summer will remain under the regulatory response column until supplemental inspections verify the root cause of the issues, appropriate actions are taken to prevent recurrence, and the white findings are closed, according to the finding. Dominion has 30 days from the issuance of the final determination to appeal the decision.
In fall 2023, the plant received a preliminary yellow finding of substantial safety significance over an inoperable emergency diesel generator. A few months later, the NRC downgraded it to white in its final determination following a regulatory conference where the Dominion team provided additional information.
