Dominion Virginia Power's North Anna Power Station has restored off-site power after an earthquake struck nearby. The station remains in an Alert, the second lowest of the four emergency classifications of the U.S. Nuclear Regulatory Commission.
The station's two nuclear reactors shut down following an earthquake near the station that occurred at 1:51 p.m. local time. The reactors shut down automatically and no damage has been reported to systems required to maintain the station in a safe condition. Several aftershocks felt in the region that occurred later today did not affect the station.
Four diesel generators supplied power to the station while the off-site power was unavailable. One of the four generators was taken off-line to repair a generator coolant leak, but a fifth generator at the station was activated to replace it until the offsite power was restored. Repairs are complete to the diesel generator, Dominion said.
The company also inspected the Lake Anna Dam after the earthquake and determined it sustained no damage. Station inspections are continuing to assure no damage has resulted from the seismic event.
No release of radioactive material has occurred beyond those minor releases associated with normal station operations.
The earthquake was felt at the company's other nuclear power station, Surry Power Station in southeast Virginia, but not as strongly. Both units at Surry continue to operate safely. Surry has exited a Notification of Unusual Event (NOUE) it declared earlier today, the least serious of four NRC emergency classifications.
U.S. nuclear power stations, including Dominion's four stations, were built to seismic standards for their regions