The Pueblo chemical agent destruction pilot plant (PCAPP), based in Pueblo, Colorado, has been safely destroying chemical weapons stored at the U.S. Army Pueblo chemical depot since 2015.

The PCAPP team is starting its final chemical weapons destruction campaign. The operation of a state detonation chamber (SDC) complex will destroy munitions that are decades old including 4.2 inch mortar rounds containing mustard agent.

"Safe elimination of the Pueblo stockpile helps the U.S. government meet its international obligations and removes a threat from the community," said Mike Costas, general manager of Bechtel's Defense & Space business line. "We're honored to continue this important mission."

Heating munitions and treating the pollution

This final campaign will be conducted in three static detonation chambers — armored, stainless steel vessels. The process involves detonating the munitions in electrically heated vessels. The agent and munitions components are destroyed. A pollution abatement system treats the gases.Igor, a training robot, lifts a 155 millimeter shell to demonstrate how liquid mustard agent is removed. Source: PCAPPIgor, a training robot, lifts a 155 millimeter shell to demonstrate how liquid mustard agent is removed. Source: PCAPP

"After years of work and preparation in getting the SDC units up and running, it is gratifying to be on our way with destruction of the third and final campaign," said Todd Ailes, project manager, Bechtel Pueblo Team. "We are making our community safer with every munition we destroy."

PCAPP began with a presidential directive and the ratification of the Chemical Weapons Conventions in 1997. This international treaty asked all member nations to destroy their chemical weapons and production facilities. Bechtel oversees the teams under contract to the Pentagon’s Program Executive Office, Assembled Chemical Weapons Alternatives to help the United States complete its treaty obligations.

Remaining weapons are stored in facilities in Pueblo, Colorado, and Richmond, Kentucky. These two stockpiles make up the last 10% of what was originally a national stockpile of more than 30,000 tons of chemical weapons at seven sites. Weapons destruction at both sites is expected to be completed by December 31, 2023.

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