The H.B. Robinson nuclear power plant will receive additional oversight, including a follow-up inspection, from the Nuclear Regulatory Commission after a violation related to the company's failure to perform adequate preventive maintenance on the dedicated shutdown diesel generator.
The Robinson plant is located near Hartsville, about 26 miles northwest of Florence, and is operated by Duke Energy.
The violation and increased oversight is linked to an inspection finding, which was discussed at a regulatory conference between Duke and the NRC in August.
After reviewing the information from the inspection and the conference, the NRC staff determined that the finding was a violation and should be classified as white, meaning it has low to moderate safety significance
The NRC evaluates inspection findings and performance indicators at commercial nuclear power plants with a color-coded system which classifies them as green, white, yellow or red, in increasing order of safety significance.
As the significance increases, the NRC heightens the level of oversight for that plant. If a plant takes appropriate corrective actions and improves safety performance, the agency returns to its normal, but still extensive, inspection schedule.
The issue was identified after the failure of the diesel's radiator fan belts and the subsequent automatic shutdown of the generator in October 2012.
There was no actual event requiring the use of that diesel generator and it was repaired and returned to service. However, the fan belts were degraded, in part, because of inadequate inspection, maintenance and periodic replacement, according to the NRC.
The belt failures could have prevented the shutdown diesel generator from being available during a loss of power or a fire.
"Overall, the Robinson plant continues to be operated safely," said NRC Region II Administrator Victor McCree. "However, the additional oversight and inspection by the NRC is warranted because we expect plants to ensure that all important equipment is properly inspected and maintained."
The additional NRC inspection will provide assurance that the causes of the issue are understood and corrective actions are sufficient to prevent recurrence.
The additional inspection has not yet been scheduled.