On Friday, the plant’s operator, Dominion Virginia Power, informed the NRC that the ground motion produced by the 5.8 magnitude quake “may have exceeded” the amount of shaking the plant was designed to withstand.
That notice prompted the deployment of the NRC team, which will also focus on why the plant lost primary electrical power for several hours and how the plant’s operators responded to the situation, said Roger Hannah, a spokesperson for the NRC’s southeast region.
The inspection is unusual, said Scott Burnell, a spokesman for NRC. Such “augmented inspection teams” are dispatched to nuclear plants “infrequently. If I had to put a number on it I’d say once every couple of years.”
During the quake, 36 “scratch plates” at the facility recorded ground motion in three dimensions, said Richard Zuercher, a Dominion spokesman. Preliminary analysis of the plates performed by a seismologist contracted by Dominion showed “the plant may have exceeded design basis for ground-force acceleration,” Zuercher said.
Zuercher would not provide details on the amount of shaking revealed by the preliminary analysis. “We want to know for sure what we have,” he said, adding that Dominion would make available a fuller analysis of the shaking by the end of the week.
Dominion has not said when the plant might be operational again. Zuercher said the company has enough power available to continue uninterrupted service despite the loss of the 450,000-home generating capacity of the North Anna plant.
- NRC ramps up inspection at Va. nuclear plant; earthquake may have exceeded plant’s design base – Signs That Utilities Knew Of Shortfall (enformable.com)
- North Anna Nuke Plant: Quake May Have Exceeded Nuclear Plant’s Safety Specs (ex-skf.blogspot.com)
- Nuclear Expert: Quake-hit Virginia nuke plant should be distributing bottled water to nearby residents – Pipes under North Anna are potentially a grave public danger (enenews.com)
- NRC Commits North Anna Nuclear Power Plant to Further Investigation – Likely to have extra margins built into the design” (enformable.com)
- North Anna Workers Find 150 Gallon Oil Spill While Purging Carbon Dioxide from Unit 2 Generator (enformable.com)
- NRC requires new look at quake risks for reactors after criticism of official response (enformable.com)
- New Photos Of North Anna Nuclear Power Plant Venting Steam And Inspections After Earthquake (enformable.com)