Nov. 06--SHIPPINGPORT -- The cause of the fire at Unit 1 at the Beaver Valley Nuclear Power Station Tuesday night is still being determined, officials said Wednesday.
"We are continuing to assess both the cause of the small electrical fire and any potential damage today," said FirstEnergy spokeswoman Jennifer Young. "The affected electrical cables are in an overhead area in the turbine building, and scaffolding is being built this morning to access the area."
Unit 1 -- which was brought back to power Tuesday after a scheduled maintenance and refueling, was shut down at about 6 p.m. the same day after operators detected a problem at the main generation breaker in the generation area of the plant, went to inspect and found a small electrical fire.
"It was really just a small area of smoking wires," Young said.
Plant workers extinguished the fire, and while outside fire departments were called, they did not enter the property because they weren't necessary. Young also said the event posed no threat to public safety.
According to the NRC event notification report, the event included both an explosion and fire in a cable tray -- a rack on which electrical and other cables sit -- located in Unit 1.
However, Young said there was no indication of an explosion in the traditional sense.
"'Explosion and fire' are words used in the plant's emergency action level guidance," she said. "We don't have indications of an explosion as we tend to think of the word -- like a large blast. Rather, the technical definition of explosion is any rapid release of energy. An electrical fault such as what occurred in this cable may cause popping or sparking -- which are considered explosions."
The incident was declared an "unusual event," the lowest level of notification required by the NRC. The unusual event has since been terminated.
It's not yet clear what caused the fire, officials said.
An NRC engineering team will be assessing the situation today and determining the next steps regarding repairs, said NRC spokesman Neil Sheehan.
"As for the NRC Resident Inspectors assigned to Beaver Valley, they responded to the plant last evening to independently verify that plant conditions were stable and to perform an initial visual inspection of the area where the damage occurred," he said. "They will closely follow the company's investigation into the cause of the event and any repair plans. Beaver Valley Unit 1 will remain shut down until those actions are completed."
Unit 2 at the Beaver Valley plant was unaffected and remains at 100 percent power. As for Unit 1, Young said Wednesday it was unclear when it would be back up and running.
"At this point, it would be premature to speculate when Beaver Valley Unit 1 will return to service," she said.
Mike Pound of The Times contributed to this report.
Copyright 2013 - Beaver County Times, Pa.
