The U. S. Army Corps of Engineers (Corps) estimates that it will spend at least $15 billion to $20 billion to clean up contamination and other hazards (hereafter hazards) at thousands of properties formerly owned, leased, possessed, or operated by the Department of Defense (DOD) or its components. These properties, located throughout the United States, are known as formerly used defense sites (FUDS). The properties may contain hazardous, toxic, and radioactive wastes in the soil and water or in containers such as underground storage tanks. Such wastes can contribute to mortality and serious illness, or pose a threat to the environment. Other hazards, including unexploded ordnance and unsafe buildings, may also be present on the properties. Concerned about the ongoing presence of defense-related hazards on property that is no longer controlled by DOD, John D. Dingell, Ranking Minority Member, Committee on Energy and Commerce, House of Representatives, and Representative Tom Sawyer asked us to determine (1) how many properties identified for potential inclusion in the FUDS cleanup program are actually eligible for cleanup under the program and require or have required cleanup, and (2) the geographic distribution, by state, of the potentially eligible FUDS properties and their locations, type(s) of hazard, including unexploded ordnance, and cleanup status. For those properties with unexploded ordnance, Representatives Dingell and Sawyer also asked us to indicate if the properties are former training ranges, which often have large amounts of ordnance present after many years of use and may be costly to clean up. Our findings are reported in Environmental Contamination: Cleanup Actions at Formerly Used Defense Sites (GAO-01-557). Appendix I of this report provides detailed information on individual properties, and appendix II provides detailed information on individual cleanup projects on those properties.