WASHINGTON - A 2.7 magnitude aftershock struck around 2:12 a.m. Sunday near Louisa, Va. It is the latest in a series of small quakes following August's 5.8 quake.
Following last year's quake, the North Anna Power station was forced to shutdown. In order to re-open, the power plant was required by the Nuclear Regulatory Commission to install a seismic detector.
Richard Zuercher, with Dominion Virginia Power, says a temporary motion detector was installed before the plant reopened in November.
He says the detector measures major ground movement and then quickly assesses the impact of a quake on the power plant.
Zuercher says after the August earthquake it took time for the information to be collected from different sites and evaluated.
"What we had to do was send this information out to experts which took some time," he says.
They waited at least a week before getting any information back.
The power plant will be installing a permanent seismic detector by the end of the year.
Zuercher says the seismic detector will help to immediately understand the impact of an earthquake.
WTOP's Kathy Stewart contributed to this report. Follow WTOP on Twitter.
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