The NRC has reviewed documents relating to an incident last fall at the Browns Ferry nuclear plant and concluded that the event was of “high safety significance” and “could have led to core damage” in the event of a particular accident.
On October 23, 2010, a valve in the low pressure coolant injection system failed to open when operators attempted to use the residual heat removal system cooling loop during refueling of the Unit 1 reactor. A records search by plant operators Tennessee Valley Authority showed that the last time that the valve had been demonstrated to work was March 12, 2009.
NRC will taking a number of steps as a result of the finding:
The finding results in increased NRC oversight at Browns Ferry including a supplemental inspection to evaluate safety, organizational and programmatic issues at the plant. The inspection, which has not yet been scheduled, will include extensive reviews of programs and processes not inspected as part of the NRC’s baseline inspection program. The facility’s safety culture will also be assessed.