Calvert Cliffs Nuclear Plant shuts down

Calvert Cliffs Nuclear Power Plant in Maryland shut down automatically at 12:40 p.m. Tuesday because of an off-site grid disturbance that caused power outages in the area.  

Exelon Corp., the plant's owner, explained that automatic shutdowns in the case of electronic disturbances are programmed in order to prevent an accident with the nuclear reactors. The reactors will be operational as soon as the power disturbances are resolved.

A report from thebaynet.com said the grid disturbance was caused by a transmission conductor becoming dislodged and falling from its support structure at the Southern Maryland Electric Cooperative's Ryceville switching station.

The Southern Maryland news site also reported that power was rerouted through the 230-kV system in Calvert and St. Mary's County.

No injuries were reported. 

On the banks of the Chesapeake Bay in Calvert County, the nuclear facility features two pressurized water reactors and is the only nuclear power facility in Maryland. The two reactors can produce 1,768 megawatts combined. Unit 1 began commercial operation in 1975 and Unit 2 started in 1977.