United States completes destruction of obsolete chemical weapons stockpile

Last week the United States destroyed its last declared chemical weapons stockpile, allowing the Organization for the Prohibition of Chemical Weapons (OPCW) to confirm that all such stockpiles worldwide are now verified gone.

It was work spanning decades, following on from the ratification of the Chemical Weapons Convention in 1997. That treaty prohibited development, production, acquisition, stockpiling, retention, transfer or use of chemical weapons by all members. The final U.S. contribution to this was a sarin nerve agent-filled M55 rocket, which was destroyed on July 7, 2023, at the Blue Grass Army Depot in Kentucky.

A joint-venture team led by Bechtel National, Inc. and Parsons Corporation handled the effort, using neutralization and explosive destruction technologies to remove more than 100,000 mustard agent and nerve agent-filled projectiles and nerve agent-filled rockets. Their work began in June 2019, and ultimately destroyed more than 523 tons of chemical agents over the intervening years.

“We have a national security imperative and moral obligation to work toward eliminating the threat posed by weapons of mass destruction,” Dr. William LaPlante, Under Secretary of Defense for Acquisition and Sustainment, said. “This is the first time an international body has verified destruction of an entire category of declared weapons of mass destruction — reinforcing the United States’ commitment to creating a world free of chemical weapons.”

At one time, the U.S. chemical weapons stockpile included more than 30,000 tons of chemical warfare agents stuffed into explosives and bulk containers. Congress first mandated destruction of that stockpile in 1986, although work to do so did not begin until 1990. Time brought new assessments, though, and requirements for alternative technologies to destroy chemical weapons by means other than incineration. The nature and location of the work changed, time and again, and included a team of companies in Colorado led by Bechtel National, which finished destroying more than 780,000 mustard agent-filled projectiles at the U.S. Army Pueblo Chemical Depot on June 22, 2023.

“This is a momentous day for the U.S. chemical demilitarization program,” Secretary of the Army Christine Wormuth said. “After years of design, construction, testing and operations, these obsolete weapons have been safely eliminated. The Army is proud to have played a key role in making this demilitarization possible.”

Now, the facilities involved in destruction will enter a closure phase for the next three to four years, according to Michael Abaie, DoD’s Assembled Chemical Weapons Alternatives Program Executive Officer. This will include disposal of secondary wastes, decontamination and decommissioning efforts for buildings and equipment, demolition, environmental permits and more.