The nation’s nuclear weapons stockpile remains a cornerstone of U.S. national security policy. As a result of changes in arms control, arms reduction, and nonproliferation policies, the National Defense Authorization Act for fiscal year 1994 required that DOE develop a science-based Stockpile Stewardship Program to maintain the stockpile without nuclear testing. After this program was established, DOE, in January 1996, initiated the Stockpile Life Extension Program. The purpose of this program is to develop a standard approach for planning nuclear weapons refurbishment activities so that the nuclear weapons complex can extend the operational lives of the weapons in the stockpile by another 20 to 30 years. Within NNSA, the Office of Defense Programs is responsible for the warheads and bombs in the stockpile. This responsibility encompasses many different tasks, including the manufacture, maintenance, refurbishment, surveillance, and dismantlement of weapons in the stockpile; activities associated with the research, design, development, simulation, modeling, and nonnuclear testing of nuclear weapons; and the planning, assessment, and certification of the weapons’ safety and reliability. A national complex of nuclear weapons design laboratories and production facilities carries out the Office of Defense Programs’ mission. Three national laboratories in this complex design nuclear weapons: Lawrence Livermore National Laboratory in California, Los Alamos National Laboratory in New Mexico, and Sandia National Laboratories in New Mexico and California. For the B61 and W76 life extension programs, Los Alamos National Laboratory is responsible for designing and developing these weapons’ nuclear explosives package. Sandia National Laboratories design non- nuclear components, such as arming, fuzing, and firing systems, foams, and electrical cables, and test the weapons’ non-nuclear components to certify safety and reliability. Lawrence Livermore National Laboratory peer reviews design and production activities. Los Alamos and Sandia National Laboratories work closely with the production plants to ensure that components meet design specifications. The complex’s four production sites include the Y-12 National Security Complex plant in Tennessee, the Kansas City Plant in Missouri, the Savannah River Site plant in South Carolina, and the Pantex Plant in Texas. The Y-12 plant manufactures critical nuclear components, such as parts made from enriched uranium, for the nuclear explosives package. The Kansas City plant produces and procures nonnuclear parts and electronic components and manufactures the new arming, fuzing, and firing system for the W76 warhead. The Savannah River Site plant fills gas bottles it receives from Kansas City with tritium and deuterium, which are used to facilitate the nuclear explosion. Last, the Pantex plant assembles all components supplied by other production plants to produce a weapon for the stockpile. See figure 1 for a summary of this process. An end to underground nuclear testing in 1992 in the United States suspended the development of weapons with new, untested designs. This suspension created a shift away from the strategy of replacing older warheads with newer designs to a new strategy of retaining and refurbishing previously produced warheads indefinitely, without nuclear testing, and with no plans to replace the weapons. To manage this new strategy of refurbishing nuclear weapons, NNSA uses a process called Phase 6.X, which it jointly developed with DOD. This process consists of the following elements: Phase 6.1, concept assessment—conducting studies to provide planning guidance and to develop information so that a decision can be made on whether or not to proceed to phase 6.2. Phase 6.2, feasibility study—developing design options and studying their feasibility. Phase 6.2A, design definition and cost study—completing definition of selected design option(s) from phase 6.2 and determining the cost of pursuing the design option(s). Phase 6.3, development engineering—conducting experiments, tests, and analyses to validate the design option and assess its potential for production. Phase 6.4, production engineering—making a strong commitment of resources to the production facilities to prepare for stockpile production. Phase 6.5, first production—producing a limited number of refurbished weapons and then disassembling and examining some of them for final qualification of the production process. Phase 6.6, full-scale production—ramping up to full production rates at required levels. DOD oversees NNSA’s refurbishment activities through the military services’ Lead Project Officer and the Nuclear Weapons Council’s Standing and Safety Committee. The Air Force or the Navy appoint a Lead Project Officer to provide day-to-day oversight over NNSA’s activities. The Lead Project Officer meets regularly with officials from NNSA, the national laboratories, and production facilities to monitor progress and understand the technical challenges. The Nuclear Weapons Council Standing and Safety Committee (NWCSSC) advises and assists the Nuclear Weapons Council, which provides policy guidance and oversight of nuclear weapons stockpile activities and is required to report regularly to the President on the safety and reliability of the U.S. stockpile. Representatives from the following organizations make up the NWCSSC: NNSA; the Office of the Under Secretary of Defense for Policy; the Office of the Assistant Secretary of Defense for Networks and Information Integration; the Assistant to the Secretary of Defense for Nuclear, Chemical and Biological Programs; the Joint Staff; STRATCOM; the Army; the Navy; the Air Force; and the Defense Threat Reduction Agency. According to DOD officials, the Lead Project Officer regularly updates the NWCSSC on the status of refurbishment activities and proposes recommendations to the NWCSSC on whether NNSA should proceed to the next phase. NNSA needs approval from the NWC to proceed to Phases 6.2, 6.3, and 6.6. As of December 15, 2008, two nuclear weapons were undergoing phase 6.X refurbishment activities. The W76 warhead was in phase 6.5, first production unit, and the B61 bomb was in phase 6.6, full-scale production. NNSA originally planned to refurbish the W80 warhead and began phase 6.3, development engineering, but in 2007, NNSA cancelled refurbishment activities for the W80 warhead because DOD planned to reduce the number of W80 warheads in the nuclear stockpile. While complete cost data on the W80 warhead do not exist, NNSA spent about $480 million from fiscal years 2003 to 2007 on refurbishment activities for it. NNSA completed the refurbishment of the B61 bomb on schedule in November 2008. However, according to NNSA and DOD officials, NNSA was not able to meet all the refurbishment objectives because it established an unrealistic schedule and failed to fully implement its Phase 6.X process. NNSA was able to meet its refurbishment schedule and avoid significant cost overruns for the B61 only because (1) DOD changed some of the refurbishment objectives, (2) NNSA was able to reuse, rather than manufacture, a critical component for the B61, and (3) the Nuclear Weapons Council significantly reduced the number of B61 bombs in the stockpile. However, the refurbished B61 bombs still do not meet all refurbishment objectives. Some of the B61 refurbishment problems could have been avoided if DOD had fulfilled its roles and responsibilities in overseeing NNSA’s life extension program activities. Since parts of the B61 bomb were beginning to age, NNSA proposed, in 1999, to refurbish the first B61 by September 2004, with full-scale production ending in 2008. However, an NNSA study completed in 2001 by the national laboratories and production facilities found that they could not meet the September 2004 date given the requirements, production capabilities, risk assessments, and Phase 6.X guidelines. Instead, the national laboratories and production facilities concluded that they would need until September 2008—4 years later than the September 2004 date proposed by NNSA—to refurbish the first weapon. This proposed schedule was considered low risk because it allowed NNSA to follow the steps in the Phase 6.X process and included contingencies to address technical challenges. NNSA did not approve this schedule, however. It was concerned that the proposed production schedule for the B61 bomb would conflict with the refurbishment of the W76 warhead, which was originally scheduled for September 2007 and considered a DOD priority. NNSA wanted to complete production of the refurbished B61 bomb before beginning full-scale production of the W76 warhead because the production facilities, such as the Y-12 plant, had limited capacity. To allow the national laboratories and production facilities more time for design, engineering, and production activities while avoiding conflicts with the W76 life extension program, NNSA set a June 2006 date for the first refurbished B61 bomb. To meet this more aggressive and, as stated in NNSA’s program plan, “success-oriented” schedule, NNSA adopted a modified Phase 6.X process that compressed and overlapped the development engineering and production engineering phases, leaving little time to conduct the experiments, tests, and analyses needed to validate design options and to certify that production facilities that manufacture and assemble parts could meet design requirements. NNSA assumed that it would not need time for development and production engineering because it would reuse rather than manufacture critical materials—one of the most critical of which was a plastic. Before fully determining whether the plastic could be reused, NNSA developed a production schedule with fixed delivery dates. However, additional tests showed that NNSA could not reuse this material because it did not function properly under certain conditions. NNSA therefore decided to develop an alternative material with superior properties that would work under all conditions.