Risk associated with the demilitarization of the United States chemical weapons stockpile

A risk assessment was performed in support of the Programmatic Environmental Impact Statement for the Demilitarization of the US Chemical Weapons Stockpile. The risks of five disposal alternatives were assessed. These were: (1) continued storage for 25 more years; (2) a single disposal site (national alternative); (3) two disposal sites (regional); (4) disposal at each of eight storage sites (on-site altenative); and (5) on-site disposal except for two sites located near high population areas, where the stockpiles from these sites would be shipped to Tooele Army Depot for disposal (partial relocation). The shipping off-site was assumed by rail except for partial relocation which was assumed to be by air. The on-site shipping was by truck. Specially designed packaging was provided similar to that used to ship nuclear materials. The assessment examined the risks assciated with transportation, incinerator operation, and handling and included both risks from internally initiated events as well as externally initiated events such as earthquakes and tornadoes. Several measures of risk were used since it was necessary to properly assess impacts on human health, the environment, and socioeconomic resources. Each measure was treated as equal since risk impacts vary among the population. Results for each of the five alternatives are presented. A selection methodology was implemented to determine an environmentally preferred alternative. The on-site alternative was judged the preferred alternative based on risk and from an emergency planning perspective.