Defense Environment Alert
an exclusive biweekly report on defense policies for cleanup, compliance and pollution prevention


Vol. 11, No. 26--December 30, 2003


MONITORING PROBLEMS PAUSE AGENT DESTRUCTION AT UTAH

The Army is working to understand and correct a problem with an air monitoring system at its Utah chemical weapons incinerator that has halted agent destruction for more than two weeks. Army sources say the military has not seen this particular monitoring problem before.

Congress has urged the Army to upgrade its monitoring system, pointing to several National Research Council reports that have recommended such changes. Lawmakers included a "sense of the Congress" statement in the Fiscal Year 2004 Defense Authorization Act that calls for improving the airborne chemical agent monitoring systems at all of the Army's chemical stockpile disposal sites in order to improve protection of the public, personnel and the environment (Defense Environment Alert, Nov. 18, p 11).

At issue at the Tooele, UT, incinerator is a passive sampling system, known as the depot area air monitoring system (DAAMS), that draws air through adsorption tubes that are collected periodically for analysis. It is one of two types of air monitors the Army uses. The other type of monitor, the automatic continuous air monitoring system (ACAMS), provides "near-real-time" alarms and continues to work properly at Tooele, sources say.

Because of the DAAMS' structure and lower air temperatures at this time of year in Utah, moisture in the gas sampling stream coming from the plant's incinerator furnaces is condensing and accumulating on the DAAMS tubes, an Army expert says. This condensate would cause any agent captured in the tube to degrade, making it impossible for the Army to confirm any ACAMS alarms, the source says.

The problem was identified through routine quality control measures, the source says.

The expert could not predict when the Tooele plant would resume operations. Army contractors originally suggested it could be as soon as a couple days, but at least one attempt to solve the problem has proven unsuccessful, the source says. "We don't have a good feel of the problem," the source says.

The Army is taking two approaches to solve the problem, focusing on both technical changes that would affect the moisture content of the gas sampling stream and examining past chemical weapons processing to see if there have been any recent changes that could contribute to the problem, the source says.

On the technical front, the Army is using forced air to blow the moisture back into the sampling stream and thus prevent it from accumulating on the DAAMS tubes. The Army is also looking at increasing the furnace temperatures to ensure any moisture remains in vapor form, the source says.