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Nuclear Weapons: NNSA Does Not Have a Comprehensive Schedule or Cost Estimate for Pit Production Capability

GAO-23-104661 Published: Jan 12, 2023. Publicly Released: Jan 12, 2023.
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Fast Facts

Plutonium pits are a key component in triggering the nuclear explosion of thermonuclear weapons. The U.S. hasn't manufactured pits regularly since 1989. The National Nuclear Security Administration has been directed to develop the capacity to make at least 80 pits a year by 2030.

We found NNSA's plans for re-establishing pit production do not follow best practices and run the risk of cost increases and delays. For example, NNSA lacks both a comprehensive cost estimate and a schedule outlining all activities it needs to achieve this capability. We recommended that NNSA follow best practices in these areas.

A glovebox at Los Alamos National Laboratory

An operator wearing gloves with their hands through a box that has openings that allow the operator to work inside an isolated environment.

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What GAO Found

The National Nuclear Security Administration (NNSA) plans to establish the ability to produce 80 plutonium pits—the central core of a nuclear weapon—per year at two sites. At Los Alamos National Laboratory, plans to produce 30 pits per year rely on a broad range of program activities, five large capital asset projects, and other projects. At the Savannah River Site, plans to produce 50 pits per year rely primarily on one large capital asset project and some program activities. Several other NNSA and Department of Energy (DOE) sites play important supporting roles. Reestablishing pit production likely represents NNSA's largest investment in weapons production infrastructure to date.

Plutonium pit production process photos


NNSA has not developed either a comprehensive schedule or a cost estimate that meets GAO best practices. NNSA's schedule includes some activities managed by its Plutonium Modernization program, but this schedule does not include all activities or milestones to achieve an 80-pit-per-year production capability and does not assign resources to activities. As a result, NNSA's pit production schedule does not meet minimum qualifications to be considered an integrated master schedule, according to GAO's Schedule Guide. Because an integrated master schedule is used for coordination, among other things, missing or incomplete activities can hinder coordination, increasing the likelihood of disruption and delay.

NNSA has not developed a cost estimate that provides a complete and structured accounting of all resources required to develop and sustain a complete scope of work. According to officials, such a life cycle cost estimate has not been completed because of concerns about releasing preliminary or uncertain information. However, a life cycle cost estimate can enhance decision-making, especially in early planning stages, as well as support budget decisions, key decision points, milestone reviews, and investment decisions. Further, NNSA has cost information, even if uncertain, it uses to develop budget estimates and inform projects' critical decisions. Using NNSA's fiscal year 2023 budget justification, GAO identified at least $18 billion to $24 billion in potential costs for the 80-pit-per-year capability. Developing a comprehensive schedule and life cycle cost estimate could improve NNSA's decision-making, the efficiency and effectiveness of their efforts, and the quality of information provided to Congress.

Why GAO Did This Study

The United States has not regularly manufactured plutonium pits since 1989. Military and legal requirements direct DOE to have capacity to produce no fewer than 80 pits per year by 2030. NNSA plans to sustain this capability into the future. According to a May 2020 NNSA report to Congress, reestablishing a pit production capability is considered critical to maintaining the nation's nuclear weapons stockpile. But because plutonium is dangerous and must be handled carefully, the production of pits for nuclear warheads is difficult and expensive. Officials testified in 2022 that 80 pits per year will not be achievable by 2030.

Legislative reports accompanying recent national defense authorization and appropriations bills include provisions for GAO to review NNSA's plutonium pit production activities, including plans, schedule, and cost. This report examines (1) the scope of NNSA's efforts to achieve the required production capability of 80 pits per year; and (2) the extent to which NNSA has met GAO best practices for an integrated master schedule and a life cycle cost estimate for achieving the capability to manufacture 80 pits per year. GAO reviewed relevant agency documents and interviewed NNSA officials and contractors.


GAO is making one recommendation to NNSA to develop a life cycle cost estimate that aligns with GAO cost estimating best practices. NNSA agreed with the recommendation. NNSA should also implement GAO's existing recommendation to develop an integrated master schedule.

Recommendations for Executive Action

Agency Affected Recommendation Status
National Nuclear Security Administration
Priority Rec.
The NNSA Administrator should ensure the head of the Plutonium Modernization program develops a life cycle cost estimate for establishing NNSA's pit production capability that aligns with GAO cost estimating best practices. (Recommendation 1)
NNSA concurred with our recommendation. In March 2023, NNSA officials stated they will develop an initial life cycle cost estimate in April 2024 and a baseline life cycle cost estimate in September 2025, following the establishment of baseline cost and schedule estimates for the Savannah River Plutonium Processing Facility and the Los Alamos Plutonium Pit Production Project. As of March 2024, NNSA indicated that they remain on this timeline, though budget documents indicate that some underlying project schedules have experienced delays. We noted in our response to agency comments that, according to NNSA's plans, the program will have reached major milestones, including the first production unit pit (fiscal year 2024) and production of 10 pits per year (fiscal year 2025), without a life cycle cost estimate if this tool is not developed before fiscal year 2026. During this time, NNSA will have spent billions of dollars without having an overall idea of total program costs. We encourage NNSA to develop both its programmatic life cycle cost estimate and integrated master schedule using GAO best practices as soon as possible, rather than waiting for project baselines that may themselves be delayed. We further encourage NNSA to view the life cycle cost estimate and the integrated master schedule as tools for managing a complex and expensive program, rather than as static documents. Developing a comprehensive life cycle cost estimate could improve NNSA's decision-making, the efficiency and effectiveness of their efforts, and the quality of information provided to Congress.

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Best practicesConstructionCost and scheduleLife cycle costsManufacturingNuclear securityNuclear weaponsNuclear weapons stockpilePlutoniumCapital assets