North Anna, Va., #1 and #2 nuclear power generation stations operated by Dominion Virginia Power seen at Lake Anna, Virginia in this aerial photo. (Paul Richards/AFP/Getty Images)

Two power plants in North Anna, Va., near the earthquake epicenter, shut down automatically when the quake hit. The Washington Post’s Steve Mufson reports that the plants lost power from the grid and switched to four diesel generators to power their electrical and cooling systems, according to a spokesman at the Nuclear Regulatory Commission.

Willie Martin, now “80-something,” worked with the contractor that built the North Anna plants in the 1970s. Martin, who felt the quake at his Virginia home, said they had built the plants specifically to withstand an earthquake. Experts came out from James Madison to show the construction workers where the fault line ran. “They said it was a fault, but the ditch looked pretty much the same on both sides to me,” he recalled.

“They must have done a pretty good job. It shaked, rattled and rolled and it didn't hurt,” Martin said.

Constellation Energy, the Baltimore-based utility and power company, said that it declared an “unusual event” at its two Calvert Cliffs, Md. nuclear power plants, the lowest of four levels of emergency.

Both units continue operating at 100 percent of capacity and are “stable,” company spokesman Mark Sullivan said in an e-mail, but the company was stepping up monitoring and inspections of its facilities.

In the Fukushima disaster, a combination of a devastating earthquake and a tsunami took out the plant’s emergency generators, leading to a nuclear meltdown.

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