Assessment of Approaches for Using Process Safety Metrics at the Blue Grass and Pueblo Chemical Agent Destruction Pilot PlantsAssessment of Approaches for Using Process Safety Metrics at the Blue Grass and Pueblo Chemical Agent Destruction Pilot Plants The Department of Defense, through the Assembled Chemical Weapons Alternatives program, is currently in the process of constructing two full scale pilot plants at the Pueblo Chemical Depot in Colorado and the Blue Grass Army Depot in Kentucky to destroy the last two remaining inventories of chemical weapons in the U. S.