Army to conduct mock aerial chem-bio attack

MIAMI, Florida (CNN) -- The U.S. Army will drop hundreds of pounds of clay dust and egg whites off the Florida coast next week, part of a four-day mock aerial terrorist attack.

The exercise aims to determine how well existing U.S. radar systems can detect weapons of mass destruction that might be dispersed from the sky using crop dusters and other aircraft.

"These tests will provide the U.S. government with initial data on the feasibility and current capability of commonly used radars to detect chemical-biological attack," said an Army statement.

An Environmental Protection Agency crop duster will drop several "environmentally benign" materials, including 1,812 pounds of clay dust, 756 pounds of egg whites, 40 pounds of an irradiated and neutralized vegetable spore called bacillus subtilis and 1,812 pounds of a chemical solution said to resemble a nerve agent.

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The Army says the materials are "routinely used" in Defense Department studies, selected in part because they will not harm humans or the environment. The substances are also said to simulate a number of chemical and biological threats.

The Army conducted a similar crop duster test on an unspecified date after September 11 at the Dugway Proving Grounds in western Utah, said Mickey Morales, spokesman for the U.S. Army Soldier Biological and Chemical Command.

That test was successful, as military radar picked up the mock chemicals, he said. But civilian radar such as Doppler, used in weather forecasting, is not as sophisticated as that used by the military -- one reason why the military decided to stage next week's tests, added Morales.

Beginning Monday, the materials will be dispersed six to 12 miles off the Florida Keys, said Morales. The entire process will take more than 40 hours, although it could be delayed if weather conditions are unfavorable, according to the Army statement.

The Army's Aberdeen Proving Grounds in northeast Maryland is running the experiment in conjunction with several government agencies. The agencies include the Federal Aviation Administration, National Weather Service, U.S. Fish and Wildlife Service, Florida Keys National Marine Sanctuary, U.S. Coast Guard and other unnamed Defense Department divisions.