In the United States, destruction of the chemical weapons stockpile began in 1990, when Congress mandated that the Army and its contractors destroy the stockpile while ensuring maximum safety for workers, the public, and the environment. The destruction program has proceeded without serious exposure of any worker or member of the public to chemical agents, and risk to the public from a storage incident involving the aging stockpile has been reduced by more than 90 percent from what it was at the time destruction began on Johnston Island and in the continental United States. At this time, safety at chemical agent disposal facilities is far better than the national average for all industries. Even so, the Army and its contractors are desirous of further improvement. To this end, the Chemical Materials Agency (CMA) asked the NRC to assist by reviewing CMA's existing safety and environmental metrics and making recommendations on which additional metrics might be developed to further improve its safety and environmental programs.