Summary: The Energy Department's (DOE) nuclear material and facility stabilization program, created in 1992, has become a major part of DOE's environmental management efforts. At the beginning of fiscal year 1995, DOE was planning to spend $813 million on managing surplus facilities that were awaiting decontamination and decommissioning and on providing electrical, transportation, and other landlord-type services at key environmental management sites near Hanford, Washington; Idaho Falls, Idaho; and Rocky Flats, Colorado. DOE officials say that they can reduce future program costs by deactivating surplus facilities--which involves removing radioactive and hazardous materials that DOE must otherwise safeguard and monitor until the facilities are decontaminated and decommissioned--and by upgrading inefficient utilities and other services at sites managed by the program. This report (1) determines the proportion of the program's fiscal year 1995 budget that is allocated to projects that could reduce the program's future costs, (2) estimates the difference between the savings that these projects could generate and the costs DOE could incur to obtain these savings, and (3) determines the reliability of DOE's estimates for net savings from major deactivation projects.