For FY2010, the Administration proposed to terminate the RRW program and requested no funds for it. The House and Senate Armed Services Committee versions of the FY2010 defense authorization bill each had a provision that would strike Section 4204a of the Atomic Energy Act, which directed the Department of Energy to establish the RRW program. Neither committee recommended providing RRW funds. On June 25, 2009, the House passed the defense authorization bill with this provision intact. The House and Senate Appropriations Committees recommended providing no RRW funds for the National Nuclear Security Administration (NNSA). While some argue for abolition of nuclear weapons, there is widespread agreement within the United States that this nation must maintain its nuclear warheads as long as it retains them. Yet warheads deteriorate with age. The current Life Extension Program (LEP) maintains them by replacing deteriorated components. The National Nuclear Security Administration (NNSA), the DOE agency in charge of the nuclear weapons program, however, expresses concerns that LEP might be unable to maintain warheads for the long term on grounds that the accumulation of minor but inevitable variations between certain original and replacement components may reduce confidence that life-extended warheads remain safe and effective. It recommends a new approach, the Reliable Replacement Warhead (RRW), described below. On the other hand, a study released in November 2006 estimates that pits, a key warhead component (see Appendix ), should have a service life of 85 to 100 years or more, which some argue makes it unnecessary to replace current warheads for decades by extending the time for which confidence in them should remain high. Reflecting NNSA's concern, Congress first funded the RRW program in the FY2005 Consolidated Appropriations Act, P.L. 108-447 . The entire description of RRW in the conference report was a "program to improve the reliability, longevity, and certifiability of existing weapons and their components." No committee report earlier in the FY2005 cycle had mentioned RRW. Congress authorized the program in the FY2006 National Defense Authorization Act, P.L. 109-163 , Section 3111. Congress has spelled out dozens of goals for the RRW program. A key goal is to increase confidence, without nuclear testing, that warheads will perform as intended over the long term. Other goals are to increase ease of manufacture and certification, reduce life cycle cost, increase weapon safety and use control, and reduce environmental burden. CRS Report RL33748, Nuclear Warheads: The Reliable Replacement Warhead Program and the Life Extension Program , by Jonathan Medalia, details 20 such goals. To achieve them, RRW would trade characteristics important during the Cold War for those of current importance, as described below. The Department of Defense (DOD) has approved this tradeoff. It would be impossible to meet all the goals simultaneously by modifying existing warheads, in part because their designs are so "tight" that NNSA is concerned that even minor changes might reduce confidence in the reliability of these warheads over the long term. As such, the RRW program would design new warheads to replace existing ones. In contrast, LEP makes changes chiefly to maintain weapons, and in particular minimizes changes to the nuclear explosive package (see Appendix ). RRW is sharply debated. Supporters anticipate that RRW will permit replacing a large stockpile of nondeployed nuclear warheads with fewer warheads in which DOD can have greater confidence over the long term, and restructuring the nuclear weapons complex (the "Complex"; see Appendix ) to be smaller, safer, more efficient, and less costly. A Defense Science Board task force finds that LEP "is clearly not a sustainable approach" and recommended proceeding with RRW. NNSA argued that RRWs "will be re-designed for long-term confidence in reliability and greater security, and ease of production and maintenance. Critics question whether some of the tradeoffs and goals are feasible, necessary, or worth potential costs and risks. For example, one commenter argued, "The plutonium research results [see footnote 2 ] obliterate the chief rationale for NNSA's emerging strategy" of RRW, while the New York Times opined that RRW "is a public-relations disaster in the making overseas" and "a make-work program championed by the weapons laboratories and belatedly by the Pentagon." Several external reviews of the program have been released. (1) The House Appropriations Committee directed NNSA to have the JASONs, a group of scientists who advise the government on defense matters, conduct an independent peer review to evaluate the competing RRW designs. The JASONs should evaluate the RRW design recommended by the POG [the RRW Project Officers Group] against the requirements defined by congressional legislative actions to date and the elements defined in the Department of Defense's military characteristics for a reliable replacement warhead requirements document. The JASON review should also include an analysis on the feasibility of the fundamental premise of the RRW initiative that a new nuclear warhead can be designed and produced and certified for use and deployed as an operationally-deployed nuclear weapon without undergoing an underground nuclear explosion test. The report was due March 31, 2007. In accordance with a schedule decided by the JASONs, NNSA, and the House Appropriations Committee, NNSA transmitted the report to Congress on September 28, and JASON transmitted the final report, in classified form, to NNSA by October 1. (See "Congressional Action on the FY2008 RRW Request," below, for details.) (2) The Nuclear Weapons Complex Assessment Committee of the American Association for the Advancement of Science studied whether RRW is the best path for addressing certain potential risks of SSP and LEP and for developing a responsive infrastructure in a report released April 24, 2007. (3) The FY2006 National Defense Authorization Act, P.L. 109-163 , Section 3111, mandated a report due March 1, 2007. It was to "discuss the relationship of the Reliable Replacement Warhead program within the Stockpile Stewardship Program (SSP) and its impact on the current Stockpile Life Extension Programs" and RRW's "feasibility and implementation." The report was delivered to Congress on May 5, 2008. It concluded, "DOE and the DoD firmly believe that it is time for the United States to seek an alternative to the current strategy of extending the lives of legacy warheads indefinitely," and "To ensure the viability of its nuclear deterrent, the United States must initiate and invest in the RRW program now—so there will be no disconnect between today's credible deterrent and the one required for the future." (4) P.L. 110-181 , FY2008 National Defense Authorization Act, Section 3121, required NNSA to report on using existing pits for RRW. The report was due on July 28, 2008, and was submitted on August 8. It concluded, "The multiple objectives of the RRW program would be best met by newly manufactured pits. Until we can achieve adequate pit production capacity, we must plan on using existing pits for any warhead replacement or life extension programs." Further, "Gravity bomb designs, due to the large available weight and volume, allow the most opportunities for desired improvements and are therefore the most technically feasible candidates for pit reuse." As discussed under "Congressional Action on the FY2008 RRW Request," below, several FY2008 reports on defense authorizations and energy-water appropriations have called for other reports related to RRW, such as linking RRW to broader issues of strategy, nuclear nonproliferation, and stockpile size. This report (1) describes the LEP, difficulties ascribed to it by its critics, and their responses; (2) shows how changed post-Cold War constraints might open opportunities to improve long-term warhead maintenance and reach other goals; (3) describes RRW and its pros and cons; (4) tracks RRW program developments and congressional action on budget requests; and (5) presents options and issues for Congress. An Appendix describes nuclear weapons, the SSP, and the Complex. Nuclear warheads must be maintained because they contain thousands of parts that deteriorate at different rates. Some parts and materials have well-known limits on service life, while the service life of other parts may be unknown or revealed only by multiple inspections of a warhead type over time. A 1983 report argued that maintenance requires nuclear testing: Certain chemically reactive materials are inherently required in nuclear weapons, such as uranium or plutonium, high explosives, and plastics. The fissile materials, both plutonium and uranium, are subject to corrosion. Plastic-bonded high explosives and other plastics tend to decompose over extended periods of time ... portions of materials can dissociate into simpler substances. Vapors given off by one material can migrate to another region of the weapon and react chemically there.... Materials in the warhead electrical systems ... can produce effluents that can migrate to regions in the nuclear explosive portion of the weapon.... The characteristics of high explosives can change with time.... Vital electrical components can change in character.... A 1987 report, written to rebut the contention of the foregoing report that nuclear testing is needed to maintain warheads, agreed that aging affects components: It should also be noted that nuclear weapons engineering has benefitted from a quarter century of experience in dealing with corrosion, deterioration, and creep since the time that the W45, W47, and W52 [warheads] entered the stockpile in the early sixties (just after the test moratorium of 1958-1961).... Most of the reliability problems in the past have resulted from either an incomplete testing program during the development phase of a weapon or the aging and deterioration of weapon components during deployment. Some feel that deterioration, while a potential problem, has been overstated. A scientific panel writing in 1999 stated, there is no such thing as a "design life."