Engineers at the Davis-Besse nuclear reactor near Toledo found a pinhole coolant leak in a pipe weld Wednesday evening while inspecting the plant.
The company's report to the NRC noted that the coolant was spraying from a pinhole in the socket weld of a three-quarter inch pipe at a 90 degree elbow between a reactor coolant pump and a safety valve.
When the leak was spotted, reactor operators immediately began a shutdown and engineers began repair preparations. The plant reached cold shutdown about 1 p.m. Thursday, said Young. Repairs were expected to be completed over the weekend.