Nuclear Weapons:

Annual Assessment of the Safety, Performance, and Reliability of the Nation's Stockpile

GAO-07-243R: Published: Feb 2, 2007. Publicly Released: Mar 5, 2007.

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In 1992, the United States began a unilateral moratorium on the underground testing of nuclear weapons. Prior to the moratorium, underground nuclear testing was a critical component for evaluating and certifying nuclear warheads. In 1993, the Department of Energy (DOE), at the direction of the President and the Congress, established the Stockpile Stewardship Program to increase understanding of the basic phenomena associated with nuclear weapons, provide better predictive understanding of the safety and reliability of weapons, and ensure a strong scientific and technical basis for future United States nuclear weapons policy objectives. The National Nuclear Security Administration (NNSA), a separately organized agency within DOE, is now responsible for carrying out the Stockpile Stewardship Program. In 1995, the President established an annual stockpile assessment and reporting requirement to help ensure that the nation's nuclear weapons remained safe and reliable without underground nuclear testing. Subsequently, the Congress enacted into law the requirement for an annual stockpile assessment (annual assessment) process in section 3141 of the National Defense Authorization Act for Fiscal Year 2003. Specifically, section 3141 requires that the Secretaries of Energy and Defense submit a package of reports on the results of their annual assessment to the President by March 1 of each year. The President must forward the reports to the Congress by March 15. These reports are prepared individually by the directors of the three DOE weapons laboratories--Los Alamos National Laboratory (LANL), Lawrence Livermore National Laboratory (LLNL), and Sandia National Laboratories (SNL)--and by the Commander of the U.S. Strategic Command (USSTRATCOM), who is responsible for targeting nuclear weapons within the Department of Defense (DOD). The reports provide each official's assessment of the safety, reliability, and performance of each weapon type in the nuclear stockpile. In addition, the Commander of USSTRATCOM assesses the military effectiveness of the stockpile. The Secretaries of Energy and Defense are required to submit these reports unaltered to the President, along with the conclusions the Secretaries have reached as to the safety, reliability, performance, and military effectiveness of the nuclear stockpile. The Nuclear Weapons Council (NWC), a joint DOD/DOE organization that coordinates nuclear weapons activities between the two departments, supports the two Secretaries in fulfilling their responsibility to inform the President if a return to underground nuclear testing is required to address any issues identified with the stockpile. Congress asked us to describe the processes that DOE and DOD have established for fulfilling the requirements of the annual assessment. To determine this process, we reviewed the major reports and briefings generated during the annual assessment cycles for 2005 and 2006, including the reports generated by the weapons laboratories and USSTRATCOM. We also interviewed DOE and DOD officials, including representatives from NNSA, each weapons laboratory, USSTRATCOM, the NWC, the Air Force, the Navy, and the U.S. Nuclear Command and Control System Support Staff. In addition, we interviewed former National Security Council staff and staff associated with the House and Senate Committees on Armed Services to obtain the perspective of the end users of the annual assessment reports.

To satisfy the requirements of section 3141 of the National Defense Authorization Act for Fiscal Year 2003, DOD and DOE have established an annual assessment process that reaches conclusions and makes judgments about the U.S. nuclear stockpile and, in particular, whether it is necessary to conduct an underground nuclear test to resolve any questions about a particular weapon type. The annual assessment process takes about 14 months to complete--during which time the nuclear weapons community collaborates on technical issues affecting the safety, reliability, performance, and military effectiveness of the stockpile--and produces seven different types of reports. The annual assessment process culminates in the "Report on Stockpile Assessments" prepared by the NWC, which includes an executive summary, a joint letter signed by the Secretaries of Energy and Defense, and unaltered copies of the weapons laboratory director reports and the Commander of USSTRATCOM report. The directors of the nuclear weapons laboratories base their reports on the technical work of their laboratories, which is derived from ongoing work associated with NNSA's Stockpile Stewardship Program, as well as feedback they receive from independent teams of experts from all three of the weapons laboratories. The Commander of USSTRATCOM bases his report on the advice of a technical advisory group, which holds an annual conference bringing together all of the organizations involved in the annual assessment, and additional operational information provided by USSTRATCOM and the military services. The NWC, supported by warhead-specific technical groups, pulls together the information from DOE and DOD. The NWC then produces an executive summary of all of the reports and prepares a joint letter from the Secretaries of Energy and Defense to the President of the United States, which is forwarded to the Congress. While the principal purpose of annual assessment is to provide analysis of and judgments about the safety, reliability, performance, and military effectiveness of the nuclear stockpile, the process would not be used as a vehicle for notifying decision makers about an immediate need to conduct a nuclear test. According to agency and congressional officials, if an issue with a weapon were to arise that required a nuclear test to resolve, the Secretaries of Energy and Defense, the President, and the Congress would be notified immediately and outside of the context of the annual assessment process. We provided a draft of this report to NNSA and DOD for their review and comment. Overall, NNSA stated that it generally agreed with the findings of the draft report. NNSA also provided technical comments, which we incorporated into the report as appropriate. DOD provided oral comments of a technical nature, which we incorporated into the report as appropriate.

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