Maine earthquake prompts ‘unusual event’ at Seabrook nuclear plant
October 18, 2012 – New Hampshire — An “unusual event” indeed. The 4.0 magnitude earthquake that rumbled across the Seacoast and beyond Tuesday evening triggered normal safety protocols at the Seabrook Station nuclear power plant. The Nuclear Regulatory Commission declared an “unusual event” — NRC-speak for the lowest of its four levels of emergency classifications — at 7:20 p.m. Tuesday. The declaration was prompted by on-site ground motion resulting from an earthquake centered near Hollis, Maine — about 50 miles from the plant. “There was absolutely no impact to the plant from the earthquake,” said Al Griffith, spokesman for NextEra Energy, the plant’s owner. Griffith said a series of mandated safety checks were conducted at the plant, concluding at 1:49 a.m., some six and a half hours after the tremor. Citing the “robustness” of the plant’s design, Griffith assured that it is capable of withstanding a far, far greater impact than Tuesday’s quake. There are seismic monitors on site and Griffith said officials will be conducting “a very thorough examination and analysis of all of our data.” An NRC resident inspector assigned to Seabrook responded to the site last night to confirm that there were no immediate safety issues at the plant, which is currently shut down for a scheduled refueling and maintenance outage. “The reactor was fully shut down at the time the earthquake occurred,” said Neil Sheehan, regional public officer for the NRC. “Following procedures used when there is seismic activity affecting the plant, NextEra personnel conducted initial walkdowns, i.e., visual inspections, and confirmed that all key safety systems were functioning properly and that there was no significant structural damage,” Sheehan said in a statement. “The company will subsequently gather more seismic data and perform more detailed inspections.” Asked about the need to be vigilant in preparing for and reacting to any seismic activity, particularly in the wake of the March 2011 disaster following an earthquake and tsunami at the Fukushima Nuclear Power Plant in Japan, Sheehan said, “What happened at Fukushima served as a vivid reminder” of why the highest safety protocols are put in place and enforced. Last April, NextEra Energy conducted a tsunami drill Tuesday at the Seabrook Station plant in order to identify strengths and weaknesses of the plant in case of such a disaster. –Sea Coast On-line
