The Vermont Yankee Nuclear Power Plant reconnected to the New England power grid at 5:18 am, Thursday morning. Operators manually shut the plant down on Sunday night to repair a leak on a 24-inch feed water pipe located in the turbine building feed pump room.
The minor leak was found to be from a weld on a one half inch metal access plug in the pipe. The access plug was used for radiography of pipe welds during the original construction of the plant. Technicians have replaced the seal weld with a more substantial weld to the plug. The minor leakage, estimated at 120 drops per minute was collected via a floor drain and returned to the reactor. There was no threat to public health or safety or to plant personnel at any time.
Operators made the conservative decision to shut the plant down Sunday night based on the information available at the time regarding the leak in the high pressure feed water system and for worker safety. Plant personnel also repaired a leak on a one inch drain line connected to the plant’s high pressure coolant injection (HPCI) system.
Prior to the shut down on Sunday, the 650 megawatt plant had been operating continuously for 163 days.
Source: Vermont Yankee. 11.11.2010
Vermont Yankee reconnects to grid
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on