STOCKTON, Tooele County — Near this small ranching community 45 miles southwest of Salt Lake City, the first incinerator of its kind in United States is burning a toxic legacy of the Cold War — 13,616 tons of nerve gas and blister agent.

With numerous shutdowns and one acknowledged release of nerve agent into the atmosphere, the Tooele Chemical Disposal Facility (TOCDF) has been a lightning rod for criticism. But residents of nearby communities seem at peace with the plant, which employs about 700. More than half of the employees live in Tooele County.

The Army's $1 billion incinerator is based at Deseret Chemical Depot, a base that also houses rows of storage igloos for the thousands of rounds of chemical arms and storage tanks.

The incinerator began its task in August 1996. By mid-January, it had burned 4,917 tons of chemical agent, 36 percent of the stockpile. The only type of material destroyed so far is GB nerve agent (a k a sarin), with VX nerve agent and mustard agent yet to be burned.

The Tooele stockpile — thousands of munitions, including bombs, projectiles, land mines, spray tanks, rockets and one-ton storage containers loaded with nerve gas or blister agent — once amounted to 44 percent of the country's entire chemical armory.

TOCDF's work is scheduled for completion by 2004.

The campaign is given urgency by the fact that nearly every month, some of the aging munitions stored in protective igloos are discovered leaking, and must be specially double-packed until they are destroyed.

The fact that the incinerator is reducing that risk doesn't mean the picture is entirely rosy. The plant has a history of controversy, mistakes and breakdowns.

But the plant's neighbors have grown used to seeing alarm systems mounted on power poles and hearing the weekly test sirens. They are not worried.

Environmentalists insist the plant may not be safe. The types of incidents that concern them were demonstrated within the past year:

The most serious release happened the night of May 8-9, 2000, when the plant vented nerve gas to the outside air. The incinerator immediately shut down and remained closed for several months.

Only a minute amount of GB leaked from the stack, but none should have escaped. State, Army and federal officials investigated. All concluded that nobody was harmed.

The Centers for Disease Control recommended changes, most of them procedural. After improvements, the plant was back in full operation in September.