ANNISTON, Ala. -- The Army destroyed about 530 gallons of sarin nerve agent in the first bulk burn of the lethal chemical at the Army's newest weapons incinerator, and the remaining 270 or so gallons are to be destroyed later this month.

The Army had expected the 15 1/2-hour burn, which began Sunday and ended early Monday, to consume the entire 800 gallons of sarin drained from rockets. Because it did not, workers will be "finetuning" the incinerator during the next burn in about three weeks to make it more efficient, Army spokesman Mike Abrams said.

"In no way would I characterize it as any failure or any problem," Abrams said. "This is what we have characterized as a shakedown period. There's no pressure on us to do any specific production."

Sarin, also known as "GB," is a nerve agent so deadly a drop on the skin can kill.

The chemical was drained from 900 M55 rockets that have been chopped up and burned since the incinerator began operating on Aug. 8.

The sarin burning is the most dangerous part of the process. The burn marked the first time the Army has destroyed a large amount of nerve agent near a populated area. Emergency planners estimate that 35,000 people live within nine miles of the incinerator.

"We are in no way interested in pushing any sort of safety envelope," Abrams said. "We're wanting to make sure everything is working correctly, and we're doing that by beginning the operations very slowly."

Meanwhile, the incinerator will resume destroying rockets later this week, possibly as early as Tuesday, he said.

The Army is testing another incinerator at Pine Bluff Arsenal near Pine Bluff, Ark., a city of about 55,000, and is expected to begin burning chemical weapons there late next year. Its other incinerators are in more remote locations: in the Pacific Ocean and the Utah desert.