OH Nuke Shuts after Water Leak

Thursday, September 15, 2016 @ 05:09 PM gHale


FirstEnergy Corp.’s Davis-Besse nuclear plant will remain idle for the next few days as the utility tries to figure out how rainwater entered the plant’s turbine building.

The water prompted Davis-Besse’s turbine generator to automatically shut down at 3:43 a.m. Saturday, said Jennifer Young, FirstEnergy spokesman.

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Davis-Besse is along the Lake Erie shoreline, in Ottawa County about 30 miles from downtown Toledo.

The company learned that a roof vent in the plant’s turbine building hadn’t fully closed, but aren’t sure why.

“Some of the water ran to an expansion joint on the turbine deck floor, where it dripped onto an electrical cabinet containing turbine controls, causing a short that shut down the turbine,” she said in explaining the latest unplanned shutdown. “The plant was shut down safely, with no impact on plant workers or the public.”

Plant employees dried out the electrical cabinet and replaced and tested affected components, Young said.

FirstEnergy is not saying how long it expects Davis-Besse to be offline, except to say it appears to be at least a few days. It doesn’t expect a lengthy outage, Young said.

The company is taking the opportunity to also replace a valve on Davis-Besse’s pressurizer, which is part of its reactor coolant system, while the plant is down for maintenance, Young said.

“Replacing this component requires part of the system to be drained, so this work will occur over the next few days,” she said.

The U.S. Nuclear Regulatory Commission (NRC) listed the unplanned shutdown as a nonemergency in online reports the agency posted on its website this morning.

The NRC said Davis-Besse was operating at full power at the time of the automatic shutdown, and also said the cause is under investigation.

“There is no known primary to secondary leakage, and all safety systems functioned as expected,” the NRC said, adding the state of Ohio, Ottawa and Lucas counties were notified according to standard procedures.