The National Nuclear Security Administration (NNSA) a separately organized agency within the U.S. Department of Energy (DOE) is responsible for providing the Nation with nuclear weapons and ensuring that those nuclear weapons remain safe, secure, and reliable. As one of the DOE major production facilities, the Y-12 National Security Complex has been DOE's primary site for enriched uranium processing and storage, and one of the manufacturing facilities for maintaining the U.S. nuclear weapons stockpile. In response to the end of the Cold War and changes in the world's political regimes, the emphasis of the U.S. weapons program has shifted dramatically over the past few years from developing and producing new weapons to dismantlement and maintenance of a smaller, enduring stockpile. The ''Stockpile Stewardship and Management Programmatic Environmental Impact Statement'' [SSM PEIS], DOE/EIS-0236, issued in September 1996, evaluated alternatives for maintaining the safety and reliability of the nuclear weapons stockpile without underground nuclear testing or production of new-design weapons. In the SSM PEIS Record of Decision (ROD), DOE decided to maintain the national security missions at the Y-12 National Security Complex, but to downsize Y-12 consistent with reduced requirements. These national security missions include (1) maintaining the capability and capacity to fabricate secondaries, limited life components, and case parts for nuclear response; (2) evaluating components and subsystems returned from the stockpile; (3) storing enriched uranium that is designated for national security purposes; (4) storing depleted uranium and lithium parts; (5) dismantling nuclear weapons secondaries returned from the stockpile; (6) processing uranium and lithium (which includes chemical recovery, purification, and conversion of enriched uranium and lithium to a form suitable for long-term storage and/or further use); and (7) providing support to weapons laboratories. During the same time period as the SSM PEIS, DOE also prepared the ''Storage and Disposition of Weapons-Usable Fissile Materials Programmatic Environmental Impact Statement'' [S & D PEIS], DOE/EIS-0229, which was issued in December 1996. This S & D PEIS evaluated alternatives for the long-term storage of fissile material. In the S & D PEIS ROD, DOE decided that Y-12 would also store surplus enriched uranium pending disposition.