Note: Unfavorable weather conditions at the U.S. Army Pueblo Chemical Depot caused a one-day delay, moving the start of chemical weapons destruction from March 17, 2015 to March 18, 2015.

ABERDEEN PROVING GROUND, Md. – March 17, 2015 – The process of destroying the chemical stockpile at the U.S. Army Pueblo Chemical Depot is set to begin today in Colorado. Final approval to commence destroying the 2,611 tons of World War II-era mustard agent stored near Pueblo was granted by the Under Secretary of Defense for Acquisition, Technology, and Logistics, Frank Kendall.

“After months of preparation, testing and scrutiny by oversight and regulatory agencies, the Pueblo team is ready to play its part in meeting our nation’s commitment to the 100 percent destruction of the U.S. chemical weapons stockpile,” said Conrad F. Whyne, program executive officer for Assembled Chemical Weapons Alternatives, the responsible government agency here.

Stockpile destruction will be initiated by the Explosive Destruction System, or EDS as it is known, located on the depot near the Pueblo Chemical Agent-Destruction Pilot Plant, or PCAPP. The EDS is an Army system selected to destroy an estimated 1,300 problematic chemical munitions that cannot be easily processed by the main plant’s automated equipment. These include munitions that have leaked in the past and are now overpacked in sealed containers, as well as “rejects” from the PCAPP, which have deteriorated physically and may not be easily processed through the main plant. The problematic munitions slated for destruction by the EDS account for roughly 0.2 percent of the total Pueblo chemical weapons stockpile.

The EDS uses explosive “cutting” charges to access the chemical agent inside a munition. Neutralization chemicals are then added and heated to destroy the chemical agent. The detonation of the cutting charge also eliminates the explosive components of the munition. The blast, vapor and fragments from this process are all contained within a heavy, sealed stainless steel vessel. Before the vessel is reopened, destruction of the chemical agent is confirmed by laboratory sampling of residual liquid and air from the interior of the vessel.

EDS has a well-documented history of safe and successful operations at various sites throughout the U.S., to include employment in Colorado at the former Rocky Mountain Arsenal, where it was used to destroy a number of recovered non-stockpile chemical munitions.

This week’s destruction operations will begin with Department of Transportation (DOT) bottles which contain chemical agent drained from selected munitions over the years to assess the condition of the stockpile. DOT bottles are approximately 25 inches high with a 7-inch diameter and are constructed of seamless stainless steel. They were developed under rigorous federal guidelines for the purpose of transporting various hazardous chemicals.

The full-scale plant, built by Bechtel Pueblo Team, is currently undergoing systemization and will destroy the majority of the stockpile beginning in the late 2015/early 2016 timeframe.