A buildup of ice caused the Fort Calhoun nuclear power plant to temporarily shut down just weeks after it restarted.
Workers with the Omaha Public Power District were making routine inspections at Unit 1 when they noticed a block of ice had formed on the shaft and the top of one of six sluice gates that control the flow of water into the plant on Jan. 8. The ice also bent the sluice gate operating shaft, which caused the gate to not close and made all four raw water pumps inoperable. Workers shut the plant down as a precaution, and there was no danger to the public or to workers, OPPD said.
The ice has since been cleared and the plant will be restarted once the gate can be lowered.
Fort Calhoun restarted in December after a two-year shutdown. The plant was down for maintenance in April 2011, but the nearby Missouri River inundated the plant and caused it to be shut down longer. A series of violations and a fire kept the plant offline. The NRC had to approve the restart of the plant.
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