The Calvert Cliffs Nuclear Power Plant plans to spend about $2 million upgrading emergency sirens within the facility's 10-mile fallout zone, company officials said last week.

The upgrade will affect 72 sirens in Calvert, St. Mary's and Dorchester counties, according to Angela Walters, a company spokeswoman.

The project will begin after the first of the year and be completed by next fall, Walters said. The current sirens were installed just over 20 years ago, she added.

"The old sirens will remain in place until the new sirens are installled, tested and activated properly," Walters said.

The Nuclear Regulatory Commission requires that nuclear facilities such as Calvert Cliffs have emergency sirens with the 10-mile fallout zone and that they test them annually. The sirens are designed to alert the public to tune to a particular radio station for information in an emergency.

Rick Woods, who oversees emergency planning for Calvert Cliffs, said one of the benefits of the new sirens is that any malfunction can be detected remotely at a centralized computer grid. During tests of the current sirens, Woods said, the plant has to have spotters at each of them to make sure they operate properly.

"Right now . . . you don't know if any or all of the sirens had sounded," he said.

With its feedback capabilities, Woods said, "The new system will tell us if there are any individual failures."

The upgrade will replace the three individual siren systems deployed in the affected counties with one uniform system, Woods said.

The new sirens also will be available for use by emergency management officials in the three counties. The system will allow the counties to blow sirens selectively when specific areas are threatened by non-plant emergencies, such as last April's tornado, according to Donald Hall, Calvert County's emergency management director.

"This system will allow us to choose any one" of the sirens, Hall said. "Right now we have one option. That's blowing all of them."

Calvert Cliffs will test its current sirens at noon Nov. 4.

Last month, the NRC cited Calvert Cliffs for violating safety regulations governing the operation of emergency sirens. The citation stemmed from the annual test in November 2001 when the 49 sirens in Calvert County that are within 10 miles of the plant failed to sound. Though the failure was traced to a computer problem at the county's Emergency Operations Center, Calvert Cliffs was still bound by the NRC rules requiring working warning systems. The plant agreed with the finding and worked with the county to correct the problem.

The NRC reported in a written statement last month that it requires that "members of the public within the emergency planning zone be notified within about 15 minutes from the time that state and local officials are notified of an emergency condition."

The remaining sirens within the 10-mile radius -- 17 in St. Mary's County and six in Dorchester County across the Chesapeake Bay -- all worked properly in the 2001 test.

The plant now conducts weekly and quarterly testing to identify individual sirens that might need maintenance.