The U.S. Army yesterday said it had found an open container of mustard blister agent buried in a vacant property in an upscale Washington, D.C. neighborhood, the Associated Press reported (see GSN, July 13).
The Army Corps of Engineers over the last 15 years had conducted four excavations of old chemical weapons and related materials buried near the American University campus, which the military used as a chemical-weapon development and testing site during World War I.
The corps began the latest project in 2007 and thought that all dangerous materials by now had been removed. The airtight structure over the dig site had been removed in March. However, workers digging in the backyard last week found the uncapped glass flask containing a minute amount of mustard agent buried at a depth of about 2 feet.
"We had judged the likelihood of making a discovery like this was low probability, but not zero probability," said project manager Dan Noble. "We have a high level of confidence that there was absolutely no public exposure here."
There was no indication from air monitors installed near the site that any mustard vapor had escaped, Noble said. Eight workers are being tested for exposure, but none have exhibited any symptoms or negative health effects.
Officials transported the flask to the Edgewood Arsenal in nearby Maryland. Further excavations have been postponed while the Army reassesses its safety protocols at the site (Brett Zonger, Associated Press/Washington Examiner, Aug. 12).