OAK HARBOR, Ohio — The public release of a 65-page report outlining more problems at Energy Harbor’s Davis-Besse nuclear plant in Ottawa County has been described as “deeply disturbing” by one of America’s most high-profile nuclear watchdogs.
And while the U.S. Nuclear Regulatory Commission said Monday the company has adequately responded to all five violations cited in a report by a special inspection team, the NRC is still in the process of determining how significant two of them are. The other three were tentatively deemed to be of low safety significance.
NRC online records showed Davis-Besse operating at 100 percent power Monday.
NRC spokesman Prema Chandrathil told The Blade that government regulators are confident the plant will continue operating safely while the agency makes its final determination.
The issues primarily focus on “multiple diesel generator failures” from July, 2019, to June, 2021, as well as a reactor trip “with multiple complicating equipment issues” this past July 8, according to a letter sent Friday to Terry Brown, Energy Harbor Nuclear Corp.’s site vice president, by Michelle W. Hayes, the NRC’s acting deputy division director in the agency’s Division of Reactor Safety.
Emergency diesel generators are one of the most important safety features of a nuclear plant because they provide backup electricity in the event of a blackout or some other emergency that causes a facility to suddenly lose power.
The federal government requires nuclear plants to have theirs in good working order.
A reactor trip is an industry phrase for an unplanned shutdown, when safety features are automatically or manually activated to immediately shut down the reactor.
Edwin Lyman, nuclear power safety director for the Union of Concerned Scientists in Cambridge, Mass., said in a tweet that he found the special NRC inspection team’s report “deeply disturbing,” even though the NRC maintains the public was not endangered.
“A deeply disturbing @NRCgov special inspection report at the Davis-Besse #nuclear reactor in #Ohio details five recent diesel generator failures and a [July] scram with ‘multiple complicating equipment issues’ compounded by operator performance failures,” Mr. Lyman said in his tweet posted Saturday morning.
David Lochbaum, a longtime UCS nuclear safety project director and one-time NRC employee now on the board of the Chattanooga, Tenn.-based Gender + Radiation Impact Project, said all five violations “were self-revealing” and should have been caught long before Energy Harbor made the NRC aware of them.
“Some of the violations involved conditions that existed for over a decade,” Mr. Lochbaum said, adding later that it appears there “were almost too many failures to count in the July trip.”
The NRC mobilized the special inspection team in response to what the agency described in a July 27 letter of at least four known failures over 16 months of emergency diesel generator start circuits, a similar failure of the station blackout diesel within the prior 24 months, and complications with the July 8 reactor trip.
Davis-Besse has two emergency diesel generators and a station blackout diesel, the NRC said.
In her letter to Mr. Brown, the NRC’s Ms. Hayes said the agency intends to issue its “final safety significance determinations and enforcement decisions, in writing, within 90 days from the date of this letter.”
“It should be out in the near future,” Ms. Chandrathil said.
One of the two outstanding violations involved “the apparent failure of licensee personnel to inspect the Emergency Diesel General Field Flash Selector Switch.” The other pertains to “the apparent failure to install an Emergency Diesel Generator Speed Switch that was suitable to the application,” according to the letter signed by Ms. Hayes.
Ms. Chandrathil said the problems, identified by Energy Harbor during testing, have been fixed to the government’s satisfaction, and the NRC is confident the diesel generators will work if there’s a sudden and unexpected loss of power at the plant.
“The plant is safe, the diesel generators have been fixed, and they're able to perform their required function,” Ms. Chandrathil said.
Energy Harbor spokesmen Jason Copsey and Todd Morgano did not respond to a request for an interview or company statement.
The NRC told Energy Harbor it will be given the opportunity to appeal any enforcement action the regulator ultimately decides it wants to take.
Davis-Besse is along the western Lake Erie shoreline, about 30 miles east of downtown Toledo.
It is licensed to operate through April 22, 2037.
First Published November 22, 2021, 11:07 p.m.
