Johnston Atoll Chemical Agent Disposal System (JACADS), the first fully integrated chemical agent disposal facility, is located on Johnston Island some 800 miles southwest of Hawaii. JACADS completed ten years of operations in November 2000, which resulted in the disposal of more than 2000 tons of nerve and mustard agents. In 1998, the Army began planning for closure and dismantling of the facility. In 1999, the NRC was asked to review the Army's planning. This book presents an assessment of planned and ongoing closure activities on Johnston Island in some detail. It also provides an analysis of the likely implications for closure of disposal facilities at eight continental U.S. storage sites.