Closing U.S. Chemical Warfare Agent Disposal Facilities

In July 2023, the last of the approximately 30,500 tons of stockpiled chemical warfare agent was destroyed.  The complete destruction of the stockpile fulfilled the U.S. treaty obligation under the Chemical Weapons Convention.

Chemical agent destruction facilities at each site destroyed the stockpile by incineration or neutralization.

Two organizations managed these activities:

Status of Chemical Agent Disposal Facilities

Two sites are currently in the closure process:

Seven sites have been closed:

  • Aberdeen Chemical Agent Disposal Facility, Aberdeen Proving Ground, Maryland
  • Anniston Chemical Agent Disposal Facility, Anniston, Alabama
  • Johnston Atoll Chemical Agent Destruction System, Johnston Atoll
  • Newport Chemical Agent Disposal Facility, Newport, Indiana
  • Pine Bluff Chemical Agent Disposal Facility, Pine Bluff, Arkansas
  • Tooele Chemical Agent Disposal Facility, Tooele, Utah
  • Umatilla Chemical Agent Disposal Facility, Umatilla, Oregon

Find more information about sites currently going through closure at Program Executive Office, Assembled Chemical Weapons Alternatives (PEO ACWA) (

The Closure Process

Before the closure process begins at a site, the U. S. Department of Defense (DoD) and site managers carefully plan, develop standard operating procedures, and conduct safety reviews. CDC then reviews these plans and procedures for public health and safety considerations.

The closure process involves dismantling, decontaminating, and demolishing the chemical agent disposal equipment and buildings. It also requires considering how the property might be used in the future and verify it meets standards described in the disposal facility’s environmental permit.

During planning of the closure process, reviews of the facility’s history and interviews with facility personnel help identify contaminated and potentially contaminated equipment and buildings. Decontamination methods are designed specifically for each facility’s type of equipment and buildings, and their level of contamination.

Depending on past levels of contamination in a facility, its equipment could be decontaminated, removed, and reused. The equipment could also be removed and disposed of as hazardous waste or left in place and demolished along with the facility’s structures. Equipment is dismantled as needed so interior surfaces can be checked for contamination. Air monitoring and chemical analyses continue during the process to verify that all materials are successfully decontaminated.

After the buildings and remaining equipment are decontaminated, the entire facility is demolished.

Air monitoring and chemical analyses also continue after demolition to verify that all materials are successfully decontaminated. After demolition, soil at the building sites is analyzed and cleaned up should it be necessary. This ensures that the property meets the standards specified in the facility’s environmental permit.

Closure Waste

Closure of chemical agent disposal facilities generates waste that includes the following:

  • Used decontamination solutions,
  • Protective clothing for workers,
  • Cleaning tools and supplies,
  • Equipment that cannot be reused or left at the facility.

In general, closure waste is handled in the same way as waste created during facility operations. Depending on its level of contamination, waste may be thermally treated at the facility, sent to a permitted hazardous waste treatment and disposal facility, or sent to a solid waste disposal facility.

Land Use after Closure of Chemical Agent Disposal Facilities

After a facility closes, its land might be used by DoD or another federal agency. DoD considers local economic conditions and public comments when determining how to use the land.

For example, land at the first facility to close, Johnston Atoll Chemical Agent Destruction System, was given to the U.S. Fish and Wildlife Service and became the Johnston Island National Wildlife Refuge. After the Aberdeen Chemical Agent Disposal Facility closed, DoD kept its office building there for use by other DoD agencies. Plans for the Newport Chemical Agent Disposal Facility’s land include a variety of commercial uses.

Public Participation

DoD holds public meetings to tell the public about closure plans. These meetings are held in communities where the chemical disposal facilities are located.

Learn more: