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Federal officials will put the North Anna nuclear plant under closer watch

The plant's reactors shut down when the August 2011 quake struck

One of its four backup generators failed to start after power was lost

CNN —  

A Virginia nuclear power plant will get closer scrutiny from regulators after one of its backup generators failed to work during the earthquake that rattled the state and surrounding region in August.

The Nuclear Regulatory Commission found workers at the North Anna plant failed to properly maintain the generator, one of four designed to keep cooling systems running in case of a power outage, the agency announced Monday. The remaining diesel-powered units operated as planned, allowing the reactors to cool after they shut down because of the earthquake, the NRC said at the time.

The plant is about 90 miles southwest of Washington and about 10 miles from the epicenter of the magnitude 5.8 quake, which was felt across much of the East Coast. There was no immediate reaction to the increased scrutiny from the plant’s owner, Richmond-based Dominion Resources, but the NRC said the company has revised its maintenance procedures since the incident.

The NRC classified the problem as one that had a low to moderate impact on safety, the third-lowest rating on its four-point scale. But the finding means the plant will be subject to additional inspections.