In 2018, the National Academies of Sciences, Engineering, and Medicine issued an Interim Report evaluating the general viability of the U.S. Department of Energy's National Nuclear Security Administration's (DOE-NNSA's) conceptual plans for disposing of 34 metric tons (MT) of surplus plutonium in the Waste Isolation Pilot Plant (WIPP), a deep geologic repository near Carlsbad, New Mexico. It provided a preliminary assessment of the general viability of DOE-NNSA's conceptual plans, focused on some of the barriers to their implementation. This final report addresses the remaining issues and echoes the recommendations from the interim study.

NNSA, a separately organized agency within DOE, manages the Plutonium Disposition program to dispose of surplus weapons-grade plutonium by burning it as MOX fuel, a mixture of plutonium and uranium oxides, in specially modified commercial nuclear reactors. In 2012, DOE forecasted cost increases of close to $3 billion over the previous estimates for the program's two construction projects, the MOX facility and the WSB for disposing of waste from the MOX facility. GAO was asked to review these cost increases and the life-cycle cost estimate. This report examines: (1) drivers NNSA identified for the cost increases; (2) the extent to which NNSA analyzed underlying causes of the cost increases; (3) steps NNSA took to hold construction contractors accountable for their role, if any, in the cost increases; and (4) the extent to which NNSA's most recent estimates met cost- and schedule-estimating best practices. GAO reviewed NNSA's draft life-cycle cost estimate and contractor estimates of the MOX project's cost and WSB schedule, compared the estimates with cost- and schedule-estimating best practices, and interviewed DOE and NNSA officials. GAO is recommending, among other things, that DOE conduct a root cause analysis of the Plutonium Disposition program's cost increases and ensure that future estimates of the program's life-cycle cost and cost and schedule for the program's construction projects meet all best practices for reliable estimates.

Disposal of Surplus Plutonium at the Waste Isolation Pilot Plant: Interim Report evaluates the general viability of the U.S. Department of Energy's National Nuclear Security Administration's (DOE-NNSA's) conceptual plans for disposing of 34 metric tons (MT) of surplus plutonium in the Waste Isolation Pilot Plant (WIPP), a deep geologic repository near Carlsbad, New Mexico. This report evaluates DOE-NNSA's plans to ship, receive, and emplace surplus plutonium in WIPP and its understanding of the impacts of these plans on WIPP and WIPP-bound waste streams. This report, the first of two to be issued during this study, provides a preliminary assessment of the general viability of DOE-NNSA's conceptual plans, focusing on some of the barriers to their implementation.

PLUTONIUM DISPOSITION PROGRAM: DOE Needs to Analyze the Root Causes of Cost Increases and Develop Better Cost Estimates

PLUTONIUM DISPOSITION PROGRAM: DOE Needs to Analyze the Root Causes of Cost Increases and Develop Better Cost Estimates