Emergency planners briefed Charles County officials today on what would happen if Baltimore Gas & Electric Co.'s Calvert Cliffs nuclear-fueled electric power plant had a major nuclear accident.

Sixty-seven sirens would blare in a 10-mile area, public information centers would be set up and mobile teams dispatched to measure the spread of radiation in a worst case situation--all contingent upon operators of the facility notifying local and federal authorities. Prompt notification is required by law.

In the past, Calvert Cliffs failed to report two "unusual events" within federal time limits. Plant officials waited more than a day to report a leak of xenon gas in February 1980. That same year, the facility was fined $8,000 by the U.S. Nuclear Regulatory Commission (NRC) when it failed to report that plant workers accidentally disconnected a back-up reactor cooling system.

Planners from BG&E and the Maryland Department of Health and Mental Hygiene told County Commissioners that although county residents are not as close to the plant as are residents of St. Mary's, Calvert and Dorchester counties, wind-borne radiation from the plant could, nevertheless, contaminate crops and animals in the area.

Plant officials are required to inform jurisdictions within 50 miles of the plant about emergency procedures every two years. Today's briefing was in preparation for a Sept. 14 drill of emergency procedures.

U.S. guidelines leave it up to county officials to draft emergency plans and to decide what actions to take during any accident, said George Wall, a BG&E emergency planner. BG&E experts would notify authorities on a conference-call hotline and keep local jurisdictions, state health and NRC officials informed, Wall said.

If dangerous amounts of radioactive gas escaped, nuclear experts would operate from a command post half a mile west of the site, Wall said. Maryland State Police, the Coast Guard, the state health department, the state Department of Natural Resources and state and local Civil Defense agencies could all respond in such a situation, officials said.