PUEBLO, Colo. (AP) — The Army has resumed destruction of obsolete chemical weapons at the Pueblo Chemical Depot after a shutdown prompted by liquid hazardous waste seeping from a storage tank. Officials say the work resumed Wednesday when another tank was returned to service. The cause of the seep is under investigation.

(credit: Bechtel.com)

Pueblo Chemical Depot is destroying 780,000 shells containing 2,500 U.S. tons of mustard agent.

Officials say the liquid that seeped out is a byproduct of the process and contained no chemical weapons. They say less than 8 ounces escaped the tank.

(credit: Bechtel.com)

Mustard blisters skin, scars eyes and inflames airways. The U.S. is destroying it under a treaty banning chemical weapons.

Pueblo Chemical Depot (credit: earthobservatory.nasa.gov)

Since starting in 2016, the plant has eradicated 132,000 shells and 774 U.S. tons of mustard.

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