A moderate breeze keeps gnats from pestering artillery soldiers positioned under camouflage netting with their 8-inch Howitzers while F-16s roar overhead.

Any stiffer and the breeze would kick tons of Dugway real estate into the air, covering the landscape with the same light-colored dust that follows convoys of military vehicles that have continually traversed the desert flatlands for the past 10 days.The steady thumping of choppers is interrupted by bursts of artillery shells from gun batteries that pound target sights.

All of the activity is part of FIREX '88 maneuvers that are in full swing in Utah's West Desert. Billed as the largest non-combat firing exercise ever, FIREX has demonstrated to Brig. Gen. James M. Miller, I Corps artillery commander, that his troops could perform their wartime mission if called on.

The 12,400 artillery troops plus several thousand more from the

Army National Guard and Army Reserve from 20 states, he said,

were anxious to come to the Utah desert to train. The exercise is giving them psychological and moral support about their ability to perform. "We didn't drag anybody here kicking and screaming," Miller said. "The people here are saying it's the greatest thing that ever happened to them."

I Corps, nicknamed America's Corps, is well-known among civilians because of the movie and television series "M*A*S*H." I Corps soldiers train for combat in the northern Pacific - primarily Korea. About 65 percent of I Corps' strength comes from guard and reserve soldiers, and about half of the 11 artillery battalions Miller commands are staffed with part-timers who could potentially be sent to Korea ahead of active-duty soldiers in the event of a conflict.

"I've done everything I can to assure those soldiers and their families that they will be safe and well-trained," Miller said.

Miller estimated the exercise put $20 million into the Utah economy. Most of the money was spent on soldiers' salaries, fuel, transportation and food. But the rental and service for portable toilets was the exercise's third largest single expense, Miller said. The fiberglass outhouses are a "luxury" not available to soldiers in an actual combat situation, but they were brought to the areas of Camp Williams, Tooele Army Depot and Dugway Proving Ground used for the exercise to mitigate environmental concerns.

Miller takes one brigade of about 1,000 reservists to Korea each summer for annual training, but FIREX provides broader training designed to help the soldiers in the trenches, and the brass behind the lines, know what works and what doesn't in the military's deployment plans.

Individually, soldiers have the heat, sand and bugs to contend with. For the commanding officers, there's the logistics of getting soldiers, equipment, food and other supplies the right places at the right times. Some of those details are done only on paper in smaller exercises. In FIREX, any more realism would require the entire exercise to be classified.

Ammunition was moving too slow during the first days of the exercise, Miller said. That's his only real complaint about how the operation has been going. To remedy the problem, shells that were delivered to gun batteries by truck were delivered by helicopter beginning Monday.

Statistics indicated there would be a number of casualties, even seven to nine fatalities, in an exercise of this magnitude. The heaviest firing is still ahead, scheduled Wednesday sometime between 10 a.m. and 2 p.m., but there had been no fatalities as of Monday. Scores of medical problems, most of them associated with the heat and dust of the desert range, have been treated at an evacuation hospital set up at Dugway, said Lt. Col. Reece Stein.

The desert has also been swarming with VIPs and military attaches from a dozen foreign countries - Sweden, Australia, Turkey, Honduras, West Germany, Denmark, Norway, Canada, Spain, Belgium, Japan and the United Kingdom.

Four-star Gen. Joseph Palastra, U.S. forces commander, a "737-load" of Pentagon officials including the general over the National Guard Bureau have also visited the exercise, Miller said. Gov. Norm Bangerter was briefed on the operation at the Utah National Guard Headquarters Tuesday morning, then was taken by helicopter to observe field exercises at Dugway. Rep. Wayne Owens, D-Utah, observed operations for several hours Saturday, and other members of the Utah congressional delegation had made tentative plans to visit before the troops start to pack their equipment Thursday.