Dominion Virginia Power is still trembling with aftershocks from the 5.8-scale earthquake that hit Aug. 23.
The quake in Louisa County, whose epicenter was 12 miles from the North Anna Nuclear Power Station, shook the plant harder than it was designed to withstand, utility officials told the U.S. Nuclear Regulatory Commission on Sept. 8. Even though the quake was powerful enough to move 115-ton casks of spent fuel at the site, Dominion officials insist that the two-reactor plant is safe and should be able to return to full service next month.
Another question involves the status of the dam at Lake Anna, about 60 miles northwest of Richmond. The dam, which keeps the 1,300-acre lake filled with fresh water, was put on a watch list of vulnerable structures by the American Society of Civil Engineers, which gave it a D-plus rating.
There were questions about the dam immediately after the quake because some Lake Anna residents noticed that the lake’s water level seemed to drop 22 inches. The lake is critically important to Dominion because it’s the sole source of cooling water for the nuclear station. Richard Zuercher, a Dominion spokesman, says there’s no damage to the dam.
Historically, Dominion has had a lot of trouble with North Anna. In 1976 the utility was fined by federal regulators for making “materially false statements” about the presence of geological fault lines underneath the plant. The plant is built to withstand a 6.1-magnitude earthquake, and the Aug. 23 event was close to that.
The questions will become pressing for Dominion if it tries to proceed with winning regulatory approval and financing for a third nuclear unit at North Anna.