The Bechtel-led team at the Pueblo Chemical Agent-Destruction Pilot Plant, or PCAPP, is marking a significant milestone: safely eliminating 100,000 munitions from the chemical weapons stockpile located at the U.S. Army Pueblo Chemical Depot in Colorado. The destruction of these weapons – all containing mustard agent – is a requirement of the Chemical Weapons Convention, an international arms control treaty signed by more than 190 nations.
“This milestone is a key step forward in achieving our mission here at PCAPP,” said Bechtel Project Manager Bret Griebenow. “It is significant, and shows the operational ability of the plant, and our team, to safely and effectively destroy the remaining weapons.”
The work is being conducted under contract to the U.S. Department of Defense Program Executive Office for Assembled Chemical Weapons Alternatives (PEO ACWA). The first-of-a-kind plant began pilot operations in 2016 after years of design, construction, and testing. The plant is processing an average of 400 munitions per day and has now disposed of more than 500 U.S. tons of chemical agent. When operations are complete, the team will have destroyed more than 2,600 tons of mustard agent in three types of chemical weapons: 155mm projectiles, 105mm projectiles, and 4.2-inch mortar rounds. When the mission is complete, the Bechtel Pueblo Team will ultimately close PCAPP.
“As we conclude our pilot testing and move to obtain our final operating permit, we are excited to see increased and consistent productivity, reliability, and sustainability of our processes and procedures,” said PEO ACWA Site Project Manager Greg Mohrman. “Achieving this milestone is a time to pause and document our successes, while continuing to focus on the safe destruction of the remaining stockpile.”
How it works: State-of-the-art robotic technology
A first-of-a-kind robotic process is used at PCAPP to neutralize weapons by removing the explosive components from each projectile. The robotics then remotely access the weapon’s interior and drain the liquid agent. The agent is chemically neutralized using hot water followed by the addition of a caustic solution so the chemical process can’t be reversed. The resulting wastewater is transferred to the biotreatment stage, which consists of large tanks containing microbes that digest and further break down the solution into brine. The brine salt is separated and disposed at a permitted facility, and the water recycled back into the plant. The metal munition bodies are heated to 1,000 degrees Fahrenheit for 15 minutes and later shipped off site to be recycled.
Moving toward completion
Once operations are complete, which is scheduled for 2023, the facility will be closed. The equipment will be dismantled, decontaminated and removed in accordance with agreements between the State of Colorado and the U.S. Army.
The Pueblo plant is the first of two remaining chemical agent destruction facilities in the U.S. to enter operations. A Bechtel-led team is currently conducting systems testing and employee training at Blue Grass Chemical Agent-Destruction Pilot Plant in Richmond, Kentucky.
Learn more about PCAPP and chemical agent destruction: