The Army said yesterday that storing 1,500 tons of potentially lethal mustard agent near a Maryland National Guard airstrip in Harford County is not as dangerous as was once thought and that it is studying measures to make it even safer.
After a six-month study, the Army said it is not necessary to take more costly and sensitive safety measures, such as closing Weide Army Airfield at Aberdeen Proving Ground, moving the stockpile or enclosing it in concrete bunkers.
In a letter to members of a state-appointed citizens commission and the Kent County commissioners, the Aberdeen commander, Maj. Gen. Richard W. Tragemann, said the new study confirms that the risk of a serious aircraft accident at the stockpile is 100 million to 1 rather than the 1 million to 1 that was projected in the late 1980s.
"Completely shutting down Weide Airfield will have a negative impact on both military and emergency preparedness for both natural and man-made disasters," General Tragemann said.
Moving the stockpile or enclosing it could cost as much as $30 million and would take several years, he said. Congress told the Army to dispose of Aberdeen's stockpile and seven others in the United States by 2005. Instead, General Tragemann said, a team of Army experts is considering safety measures that could cost several million dollars: constructing a netlike structure of steel cables over the stockpile to deflect aircraft, installing an automatic fire-suppression system and erecting barricades around the stockpile.
The nine-member Army team is to issue a report within 30 days.
Last summer, the Maryland Citizens' Advisory Commission for Chemical Weapons Demilitarization suggested closing Weide Airfield or moving the stockpile to lessen the risk of a serious accident. The commission, chartered by Congress and representing residents of Baltimore, Harford and Kent counties, also asked the Army to study whether the stockpile could be housed in bunkers to protect it in the event of an aircraft crash. If the stockpile caught fire, it could create a toxic cloud that could drift into nearby communities.
The stockpile is about a mile east of the airfield, the Maryland Army National Guard's main airstrip. About 70 helicopters kept at the airstrip would be used to respond to natural disasters and other emergencies in Maryland.
The Army also uses the airstrip to ship small quantities of dangerous and deadly chemicals to private laboratories and military installations throughout the country.
Local, state and federal emergency planners are to meet today and might discuss the Army study, said Jennifer Mann, spokeswoman for the Maryland Emergency Management Agency. Of the eight chemical weapons storage sites in the country, Aberdeen's mustard agent stockpile poses the highest risk of a serious accident, according to a report last year by the National Research Council. Aberdeen's stockpile is the only one kept outdoors so close to an airfield. About 300,000 people live within 15 miles of the stockpile in Baltimore, Harford and Kent counties.
"They have recognized that there are measures the Army can take to mitigate the risk to the general public . . . rather than asking the public to protect itself from the stockpile," John Nunn, a Kent lawyer and co-chairman of the citizens panel, said of the Army study.
Mr. Nunn said the findings also mean that there is no rush to burn the stockpile in a huge incinerator, as the Army has proposed.
The commission's members and others have urged the Army to use chemical and biological means of detoxifying the mustard agent, and the Army is spending $45 million on such "neutralization" research.
In a related matter, the Kent commissioners said yesterday that they see no need for sirens that would warn of an accident at the stockpile. The state hopes to award a contract next month for the installation of 41 warning sirens in Baltimore, Harford and Kent counties.