LUSBY, Md. - Constellation Energy Nuclear Group says it has shut down one of two reactors at its Calvert Cliffs plant in southern Maryland after a malfunction caused a drop in power generation.
A spokesman said Monday that a control rod unexpectedly dropped into the reactor core. Control rods are used to regulate the pace of the nuclear reaction.
A Nuclear Regulatory Commission spokesman says such events are infrequent but do not pose a risk to the public. He says shutting down the unit for inspections and maintenance was a prudent decision.
Plant spokesman Kory Raftery says he can't predict when Unit 1 will return to operation. He says Unit 2 is running at full power.
The plant is located along the Chesapeake Bay near Lusby, about 70 miles south of Baltimore.
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