The Pueblo Chemical Agent-Destruction Pilot Plant (PCAPP) is destroying the remaining U.S. chemical weapons stockpile stored at the U.S. Army Pueblo Chemical Depot (PCD) in Colorado. The original stockpile consisted of approximately 780,000 total chemical weapons containing mustard agent. The Colorado stockpile originally comprised three chemical munition types: 155mm and 105mm projectiles and 4.2-inch mortar rounds. The first two campaigns are complete. The remaining 4.2-inch mortar round campaign is expected to end by the Chemical Weapons Convention treaty commitment of Sept. 30, 2023. U.S. public law mandates stockpile destruction by Dec. 31, 2023.

Project Update:

• Government officials and systems contractor management convened in January for what may be the last operational In Process Review meeting. Discussions focused on the current plan for finishing demilitarization activities before transitioning to closure and its associated tasks. During the meeting, officials were briefed on the plan to process the remaining 68,500 4.2-inch mortar rounds that contain two mustard agent types, HD and HT, with HD being the most difficult to process. Walton Levi, site project manager, PCAPP, received the Department of the Army Civilian Accommodation Medal as part of the review.
• Pre-closure activities have begun as the plant has destroyed more than 92% of the chemical agent stored at PCD. Patrick Sullivan, research scientist, PCAPP, has taken on closure lead responsibilities.

Main Plant Update:

• In late January, state regulators approved the full processing rate for the destruction of HT mustard-agent 4.2-inch mortar rounds in the main plant. With approval from the Colorado Department of Public Health and Environment (CDPHE), crews can begin to destroy the more than 18,000 HT mustard rounds that remain. Destruction operations for the 47,000 HD 4.2-inch rounds have yet to receive CDPHE consent as crews are in testing to resolve the issue of residue lingering in the base of the mortars.

SDC Update:

• CDPHE personnel approved the Multiple Pathway Health Risk Assessment submitted in November for the SDC complex, which will allow the SDC units to operate at 100% capacity. The workforce is awaiting approval of a permit modification request before full processing can commence.
• Crews operating the SDC complex at the Pueblo plant ended the year with the highest monthly destruction totals since the elimination of 4.2-inch mortar rounds began in February 2022. The SDC workforce destroyed 5,139 4.2-inch mortar rounds in December, which surpassed the previous best month total of 4,101 in November. In the last 11 months, workers at the SDC complex have eliminated more than 29,000 rounds from the original stockpile of more than 97,000 4.2-inch mortar rounds.

PCAPP Class 2 Permit Modification Requests B060 and B061–Public Meeting
Feb. 22, 2023, at 2 p.m. MST. The meeting can be accessed with Zoom via computer or mobile app by typing https://tinyurl.com/4t9hppwv into your browser or call by dialing 1 (719) 359-4580 and, when prompted, use Meeting ID 844 3279 1550.

Permitting Working Group and Biotreatment Utilization Group Meetings
Feb. 22, 2023, at approximately 3 p.m. MST

Colorado Chemical Demilitarization Citizens’ Advisory Commission Meeting
Feb. 22, 2023, at approximately 3 p.m. MST
Zoom meeting information:
Computer: Zoom
Phone: 1 (669) 444 9171 Meeting ID: ‪844 3279 1550#
For information, please contact the Pueblo Chemical Stockpile Outreach Office at 1 (719) 546‑0400, or pueblooutreach@iem.com

PCAPP is a facility built to destroy the chemical weapons stockpile stored at the U.S. Army Pueblo Chemical Depot in Colorado. The main plant uses neutralization followed by biotreatment and is supplemented by Static Detonation Chamber units in destroying 4.2-inch mortar rounds. The safety of the workforce, neighboring communities and the environment is the project’s priority.