DENVER—The Army now expects to use explosives to destroy about 38,000 mustard agent shells at the Pueblo Chemical Depot, down slightly from the 40,000 it estimated earlier this month, officials said Tuesday.
The new estimate is at least the fourth one that officials have used in the past 12 months. The changes came as the Army twice revised its plans for getting rid of the obsolete shells stored in Pueblo.
“We’ve had some difficulty coming up with numbers,” said Kevin Flamm, who oversees the destruction of chemical weapons at Pueblo and at the Blue Grass Army Depot in Kentucky.
He said officials are “trying to be transparent in a very dynamic atmosphere where the numbers are changing.”
He disclosed the latest estimate in an interview with The Associated Press. Flamm, whose agency is based in Maryland, was in Colorado to meet with Pueblo community leaders.
Flamm said 40,000 was a rough estimate arrived at by rounding up. He said the final tally could be lower than the new estimate of about 38,000, but officials want to make sure environmental reviews are based on the highest likely number, he said.
The mustard agent is being destroyed to comply with an international treaty.
About 780,000 shells containing 2,600 tons of mustard agent are awaiting destruction at the depot outside Pueblo, about 100 miles south of Denver.
The Army plans to destroy most of the shells by dismantling them and then draining and neutralizing the mustard agent with water and bacteria. Shells deemed unsuitable for that highly automated process will be exploded in closed chambers.
As of late last year, the Army planned to blow up only damaged or leaking shells, which were expected to number between 500 and 1,000.
In December, officials announced a plan to explode as many as 125,000 shells that weren’t leaking or damaged in hopes of speeding up the process and demonstrating to other nations that the U.S. is serious about eliminating chemical weapons—even though it will miss the 2012 treaty deadline.
Earlier this month, the Army shelved that plan, saying it would take too long to meet Environmental Protection Agency requirements.
At the same time, officials raised the number shells they expected to be unsuitable for the automated dismantling process, based on test runs. They also decided to use explosives on 28,375 shells that were older and had fewer safeguards than the others.
That led to Flamm’s estimate of 40,000 shells, now revised to 38,000.
He stressed those are planning numbers and could change again.
“We’re not trying to hide anything, not trying to alarm the community,” he said. “I don’t want them to think I’m low-balling” the number of shells that might be blown up.
