HERMISTON - A small amount of mustard agent was discovered at a sampling station on the Umatilla Chemical Depot on Friday. Officials say subsequent tests revealed that the agent was in a sampling tube and never in the air.
The depot uses diluted amounts of chemical agents in its sampling tubes to test equipment in its 13 on-base stations, the Army said. The stations are designed to sample air to test both what is in the air already and for the possible presence of mustard, GB or VX agents, the three chemical agents stored at the depot.
Depot Commander Lt. Col. Tom Woloszyn said depot staff used mobile air monitors to do additional testing on Friday and found no trace of agent in the air. Visual inspection of tanks in the mustard igloo showed no leaks, Woloszyn said in a press release.
Mustard solidifies at 58 degrees, yet the highest temperature on Friday was 41 degrees, the Army says. Because of this, "it is not possible for mustard to have been present in the ambient air," the release said. Deport workers reported the temperature inside the mustard igloo at 34 degrees.
The monitoring station was near the standard magazine, roughly in the center of the depot, not far from the administrative area, said depot spokeswoman Mary Binder.
Chris Early, the protocol manager for Washington Demilitarization Co., said this morning that the mobile air monitors tested the air on Friday and the visual inspection of the mustard shed was conducted on Saturday morning.
The air stations pull air in through sampling tubes so that any airborne materials will cling to absorbent materials in the tubes. The unit was apparently tested Friday morning.
Early said this is the first time something like this has happened. It may have been caused by a sampling tube that wasn't washed out well enough - the cold temperature may have caused a small amount of the diluted agent to solidify in the tube.
Early said the scientists who test the sample tubes have identified procedural changes that should keep this from happening again.
"There wasn't any mustard agent in the ambient air, that's the key thing that people have to remember," Early said.