Virginia quake's motion may have exceeded nuclear plant's design
More federal inspectors are en route to Virginia's North Anna nuclear power station after early data indicated the plant may have experienced more shaking than it was designed to withstand during last week's 5.8 earthquake.
The Nuclear Regulatory Commission sent additional inspectors to the site, about a dozen miles from the quake's epicenter near Mineral, Va.
The added scrutiny was triggered by preliminary data reported Friday by the plant's operator, Dominion Virginia Power, which signaled that ground motion caused by the quake surpassed the plant's design. Jim Norvelle, a spokesman for Dominion, said a more detailed seismic analysis should be complete by the end of the week.
The plant remains offline. It cannot be restarted until its operator can show the NRC that it remains safe.
Dominion and NRC inspectors are conducting a thorough inspection of the safety systems and physical structures of the plant. So far, Norvelle said, they have found no indication of significant damage, but there are signs of the quake: thermal insulation that shook off pipes within the nuclear containment units, cracks in ceramic insulators on the plant's transformers and fallen ceiling tiles at a commercial office building just outside the fence that surrounds the power station.
The additional federal inspectors "should not be interpreted to mean that Dominion staff responded inappropriately or that the station is less safe as a result of the quake," NRC Region II administrator Victor McCree said in a news release. "[The team of investigators] provides us with the resources needed to completely understand all the effects at North Anna and gather important information for the NRC's continuing evaluation of earthquake risk at all U.S. nuclear plants."
Photo: The North Anna Power Station operated by Dominion Energy remains offline after the East Coast's 5.8 earthquake. Credit: Scott Olson / Getty Images