The Army is preparing to begin the second phase of a pollution study project that will require 180 burning and explosive tests during the next two years in Utah's western desert, officials say.

"The purpose of the tests is to measure the amount of pollution, if any, obtained by the local environment during open burning of old explosives, powder and munitions," said Ken Jones, a scientist with Dugway Proving Ground's Materiel Test Directorate.The research, using an airplane specially equipped with pollution monitoring gear, stems from pressure by the Environmental Protection Agency to re-examine methods of disposing of old munitions.

For years the military has disposed of obsolete powder, explosives and munitions by either burning or exploding them outdoors, Dugway officials say. But, in recent years, the EPA has questioned the method as possibly damaging to the environment.

In the first phase of the study, managed by the Tooele Army Depot, researchers collected data by using a pollution monitoring helicopter. But officials said, because of aircraft vibration and other problems, little useful information was obtained.

The second phase, jointly managed by Dugway and the Army Materiel Command, based in Alexandria, Va., is to begin in March. It will utilize a twin-engine Otter, an atmospheric research plane equipped with a variety of pollution detectors and a massive computer system for sample collection and analysis, Jones said.

Air samples from open burning and detonations of munitions and explosives will be piped into the craft's analyzers and bags. And, on the ground, soil and vegetation samples will be collected and analyzed for contamination.

"The project started out at $2.5 million, and has now been expanded to $3.5 million," said Jones. "It's a very big program for Dugway, and could very well lead to a second test mission for us."

Dugway's primary mission is chemical and biological defense testing, and testing of battlefield smoke and obscurants.