The U.S. Army Chemical Materials Agency reported a trace amount of mustard gas leaked from a storage container Thursday at the Deseret Chemical Depot in Tooele County.

Workers wearing protective clothing tightened a plug from which the chemical was leaking and decontaminated the container, the agency said in a press release.

"The earth-covered storage structure was filtered and no vapor escaped to the environment," according to the agency. "Tooele County officials were notified and there was no danger to depot workers or surrounding communities."