The U.S. Army Pueblo Chemical Depot (PCD) is located in southeastern Colorado, encompassing approximately 23,000 acres. The depot’s mission is the safe, secure storage of mustard agent in projectiles and mortar rounds, while protecting the environment, workforce and surrounding communities. The weapons, stored and monitored at the depot since the 1950s, are obsolete and are being destroyed in accordance with Chemical Weapons Convention commitments and Congressional mandate. The local community, in addition to state and federal regulators, is extensively involved in the chemical weapons destruction program.
Pueblo Chemical Agent-Destruction Pilot Plant
Located on PCD, the Pueblo Chemical Agent-Destruction Pilot Plant (PCAPP) includes a variety of facilities for purposes including agent processing, energetic processing, control and storage, munitions storage, biotreatment, entry control, utility, laboratory, personnel maintenance and other support tasks. The Bechtel Pueblo Team (BPT) was awarded the systems contract to design, construct, systemize, pilot test, operate and close the main facility.
The Program Executive Office, Assembled Chemical Weapons Alternatives program, known as PEO ACWA, is responsible for managing the destruction of the Pueblo chemical weapons stockpile and overseeing the BPT contract. PEO ACWA is headquartered at Aberdeen Proving Ground, Maryland.
In July 2002, Department of Defense officials selected neutralization followed by biotreatment as the disposal technology to destroy the stockpile. Neutralization followed by biotreatment uses hot water to neutralize the chemical agent, effectively destroying the mustard agent molecules. The resulting hydrolysate is mostly water and thiodiglycol, a common industrial chemical that is readily biodegradable. Ordinary sewage treatment bacteria, or microbes, consume the organics in the hydrolysate. Besides being a common phenomenon in nature, the science of using microbes to help dispose of hazardous waste has existed for decades. Sewage treatment facilities across the country use microbes every day to help break down raw sewage.
Some munitions will not be able to be easily processed through the main destruction plant. These problematic munitions included those that leaked or were sampled in the past and were overpacked, as well as “rejects” whose condition does not allow for automated processing. These munitions will be safely processed in PCAPP’s Static Detonation Chambers.
The Pueblo Chemical Stockpile Outreach Office and the Pueblo Chemical Depot Public Affairs Office keep the community informed of issues regarding chemical weapons destruction. The offices respond to inquiries, provide information materials and coordinate guest speakers for a variety of different civic groups and organizations. The offices work closely with the Army, state regulatory agencies and local and state emergency preparedness authorities to create a comprehensive public involvement and outreach program.