One reactor at Calvert Cliffs nuclear power plant in southern Maryland has resumed operations after electrical problems stemming from a leaky roof caused an unexpected shutdown on Feb. 18, a spokesman said Monday. The Lusby plant's second reactor remains out of service for refueling, said David Fitz, a spokesman for Constellation Energy Nuclear Group, a subsidiary of Constellation Energy Group. Inspectors from the U.S. Nuclear Regulatory Commission went to Calvert Cliffs last week to investigate the cause of the shutdown. They will return to the plant in several weeks to review the company's reports on the incident and will produce their own analysis within 45 days, said Diane Screnci, a commission spokeswoman. Company officials said melting snow on an electrical breaker caused loss of power to one reactor, which triggered the second to also shut down. Fitz said the reactor came back on line at 12:18 a.m. Sunday after crews completed repairs and verified there were no safety issues. The unit was operating at 96 percent reactor power Monday afternoon, producing 850 megawatts, Fitz said.

- Liz F. Kay