TOLEDO, Ohio – The operator of an Ohio nuclear plant along Lake Erie has found several more cracks in the concrete building housing the nuclear reactor and says some cracks detected earlier have grown a bit.
But the findings do not mean the structure shielding the nuclear reactor at the Davis-Besse plant near Toledo is unsafe, FirstEnergy Nuclear Operating Corp. said Friday.
"The robust building continues to function safely and reliably," Davis-Besse Site Vice President Ray Lieb said in a statement.
The reinforced concrete building surrounds a 161/27-inch thick carbon steel vessel containing the reactor and is intended to protect the plant from events like storms or terrorist attacks and protect the public in the event of a catastrophe.
The company said high-definition cameras now used for inspecting core samples provide greater clarity and mobility and identified cracks that weren't visible with previous inspection equipment.
Several hairline cracks were found in the structure's 2.5-foot thick concrete two years ago. FirstEnergy determined they were caused by wind-blown moisture seeping into the concrete during a blizzard and freezing and that the building's structural integrity wasn't affected.
At that time, the Nuclear Regulatory Commission accepted a company proposal to weatherproof the concrete and set up a monitoring and testing program to make sure the building remains sound. The agency said Friday that it was aware of the latest findings and had been closely following the issue, The Plain Dealer in Cleveland and The Blade in Toledo reported.
"Based on the current information, this issue does not compromise the safety of the plant or the public," the federal agency said in a statement.
NRC spokeswoman Viktoria Mitlyng said in an email to the Plain Dealer that the agency also sent its own structural inspector to Davis-Besse.
FirstEnergy is seeking a 20-year renewal of Davis-Besse's operating license, which expires in 2017.
Michael Keegan, a spokesman for one of four anti-nuclear groups opposed to the renewal told the Blade that he believes the structure is compromised.
Davis-Besse is in Oak Harbor, about 25 miles east of Toledo.