Published: August 07, 2008 08:26 am            

Second leak detected in two weeks

Depot: Mustard gas confined to igloo

The second leak of mustard gas in two weeks has been detected in a storage igloo at the Blue Grass Army Depot.

“The extremely low-level leak was detected by a mobile gas chromatograph and then confirmed using a more detailed procedure that requires a longer period of analysis,” said Dick Sloan, public information officer for the depot’s chemical activity.

“This leak, like the one that occurred July 28, is an extremely low concentration, confined to the interior of the igloo and poses no threat to the community or the environment,” he said.

Both leaks came from 155-millimeter artillery shells.

The amount detected was 0.33 STEL, “an extremely low level,” Sloan said.

STEL stands for Short Term Exposure Limit. One STEL is the maximum concentration to which workers can be exposed for short periods, usually about 15 minutes or less, he said.

“Typically, low-concentration mustard leaks are detected at one-fourth to three-fourths of a STEL,” Sloan said.

“One STEL equals about 0.00001 milligrams per cubic meter,” he said. The Army’s detection capability compares to detecting one grain of salt in 34 freight cars of potato chips, he said.

A 1,000-cubic-foot-per-minute filter has been connected to the igloo to ensure no mustard vapor escapes the igloo, Sloan said.

The igloos are normally vented, but based on size of the leak, “There is a very low probability that any agent escaped from the two igloos,” he said.

Each igloo contains thousands of artillery shells, Sloan said, and chemical activity employees are still searching for the second leaker.

The July 28 leak was the first leak of mustard agent at the depot since Aug. 7, 2005, Army officials said then.

That leak was located Wednesday within the igloo and overpacked into a leakproof container.

“The toxic chemical workers who spent hours in very hot protective clothing are the true heroes of this incident,” said Lt. Col. David Musgrave, commander of the Blue Grass Chemical Activity. “They spent countless man-hours sweltering in rubber protective clothing wearing gas masks sorting through thousands of artillery shells to find one that was leaking.”

It will be a few days until the overpacked shell will be moved into another igloo that contains only overpacked mustard munitions.

In the meantime, the original igloo will be monitored daily to ensure that there are no other leaking shells that were masked by the one that was overpacked.

“It is not until we are sure that the igloo contains no further leaking munitions that we can close out this incident,” said Musgrave.

The second mustard leak is now undergoing the same intense scrutiny that located the first leak.

Local and state emergency management agencies as well as environmental agencies are being constantly updated about this incident

Leaks occurring during the hottest time of the year is not a coincidence, Sloan said.

Warm summer temperatures “tend to thaw the volatile blister agent, occasionally causing higher internal pressures,” he said. “That, plus the age of the munitions, may have some bearing on the frequency of leaks.”

The likely location of the leaks is around the O-rings near the top of a projectile, where lifting plugs are attached, Sloan said.

“To the best of our knowledge, the O-rings are OK,” he said. “If the internal pressure builds up to a certain point, however, it can defeat the O-ring for an instant and let a little vapor out.”

The two recent leaks should not be interpreted as a trend indicating heightened volatility of the mustard agent weapons, Sloan said.

“We track trends, and until last month, we hadn’t had a mustard-agent leak for three years,” he said.

The leak appears to be “very minor, nothing to be concerned about,” said Craig Williams of the Chemical Destruction Citizens Advisory Board. “Once again, the Army has shown that it can monitor this thing with diligence.

“Just because there’s a couple in a row, doesn’t mean there’s a pattern of leaks over time. In fact, its just the opposite.

“We just need to keep pushing to get the (destruction) plant up and going, so we can be rid of (the chemical weapons.)”

Williams disputed critics who claim the depot’s chemical munitions already would have been destroyed, as they have in Alabama and Arkansas, if the Army had chosen to build the originally proposed incinerator at the depot instead of a chemical destruction plant.

“That’s factually inaccurate,” he said. “I’ve explained the chronology of the U.S. (chemical weapons destruction) program to these people many times. If we had stuck with incineration, (the incinerator) would still not have been built.”

Williams says he understands the critics’ frustration.

“They are frustrated, as I am, that the stuff is still here, and they’re looking for somebody to blame it on, so they are picking me,” he said.

“I don’t mind being criticized, but they should get their facts straight.”

Bill Robinson can be reached at brobinson@richmondregister.com or at 623-1669, Ext. 267.

        

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