One of two nuclear reactors at Calvert Cliffs, Md., went off-line automatically overnight because of Hurricane Irene, according to Constellation Energy Nuclear Group.
The facility and community is safe and stable, Constellation spokesman Mark Sullivan said.
Wind from the hurricane apparently blew a piece of aluminum siding into a transformer, causing the Unit 1 reactor to go off-line, Sullivan said. Unit 2 is operating at 100 percent.
A low-level emergency was declared, Sullivan said.
There is no time table for Unit to be back online. Constellation is following its emergency response plan, Sullivan said.
In New Jersey, operators of another nuclear power facility shut the power plant down preemptively. The plant, Oyster Creek Generating Station, sits on N.J.'s coastline at Forked River.
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