Most of these costs are up-front capital costs. When DOE missed  its 1998 deadline to begin taking custody of the waste, owners of spent fuel  with contracts for disposal services filed lawsuits asking the courts to  require DOE to fulfill its statutory and contractual obligations by taking  custody of the waste. Based on DOE’s Cost Estimates, Yucca Mountain Will Likely Cost from $41 Billion to $67 Billion for 153,000 Metric Tons of Nuclear Waste, but Costs Could Increase

Our analysis of DOE’s cost estimates found that (1) a 70,000 metric ton  repository is projected to cost from $27 to $39 billion in 2009 present value  over 108 years and (2) a 153,000 metric ton repository is projected to cost  from $41 to $67 billion and take 35 more years to complete. In addition, the Department of the Treasury’s judgment fund will pay the  government’s liabilities for not taking custody of the nuclear waste in 1998,  as required by DOE’s contract with industry. Centralized Storage Would Provide a Near- Term Alternative, Allowing Other Options to Be Studied, but Faces Implementation Challenges

Centralized storage would provide a near-term alternative for managing  nuclear waste, allowing the government to begin taking possession of the  waste within approximately the next 30 years, and giving additional time  for the nation to consider long-term waste management options. However,  centralized storage does not preclude the need for final disposal of the  waste. The estimated cost of implementing  centralized storage for 100 years ranges from $15 billion to $29 billion for  153,000 metric tons of nuclear waste, and the total cost ranges from $23  billion to $81 billion if the nuclear waste is centrally stored and then  disposed in a geologic repository. Over time, the storage systems  may degrade and institutional controls may be disrupted, which could  result in increased risk of radioactive exposure to humans or the  environment. In addition, NWPA provided authority for DOE to  site, construct, and operate a centralized storage facility, but such a facility  could not be constructed until NRC authorized construction of the Yucca  Mountain repository, and the facility could only store up to 10,000 metric  tons of nuclear waste until the repository started accepting spent nuclear  fuel. On-Site Storage Would Provide an Intermediate Option with Minimal Effort but Poses Challenges that Could Increase Over Time

On-site storage of nuclear waste provides an intermediate option to  manage the waste until the government can take possession of it, requiring  minimal effort to change from what the nation is currently doing to  manage its waste. The estimated cost to continue storing  153,000 metric tons of nuclear waste on site for 100 years range from $13  billion to $34 billion, and total costs would range from $20 billion to $97  billion if the nuclear waste is stored on site for 100 years and then  disposed in a geologic repository. The additional time in on-site storage may also make the waste safer to  handle because older spent nuclear fuel and high-level waste has had a  chance to cool and become less radioactive. As a result, on-site storage  could reduce transportation risks, particularly in the near-term, since the  nuclear waste would be cooler and less radioactive when it is finally  transported to a repository. For every year after 2020 that DOE fails to  take custody of the waste in accordance with its contracts with the reactor  operators, DOE estimates that the government will continue to accumulate  up to $500 million per year beyond the estimated $12 billion in liabilities  that will have accrued up to that point; however, the outcome of pending  litigation could substantially affect the government’s total liability. Appendix I: Scope and Methodology

For this report we examined (1) the key attributes, challenges, and costs  of the Yucca Mountain repository; (2) alternative nuclear waste  management approaches; (3) the key attributes, challenges, and costs of  storing the nuclear waste at two centralized sites; and (4) the key  attributes, challenges, and costs of continuing to store the nuclear waste at  its current locations. To obtain comments from a broad group of nuclear waste management  experts, we compiled the initial assumptions and component costs that we  gathered from a small group of experts into a data collection instrument  that included    a description of the Yucca Mountain repository and our proposed nuclear  waste management alternatives—on-site storage and centralized storage— and attributes and challenges associated with them;   our initial assumptions that would identify and define the processes, time  frames, and major components used to bound our hypothetical centralized  and on-site storage alternatives; the major component costs of each alternative, including definitions and  initial cost data; and   components associated with each alternative with a high degree of  uncertainty that we did not attempt to quantify in terms of costs. Using these steps, we discounted all annual costs to 2009 present value.
Why GAO Did This Study

High-level nuclear waste--one of the nation's most hazardous substances--is accumulating at 80 sites in 35 states. The United States has generated 70,000 metric tons of nuclear waste and is expected to generate 153,000 metric tons by 2055. The Nuclear Waste Policy Act of 1982, as amended, requires the Department of Energy (DOE) to dispose of the waste in a geologic repository at Yucca Mountain, about 100 miles northwest of Las Vegas, Nevada. However, the repository is more than a decade behind schedule, and the nuclear waste generally remains at the commercial nuclear reactor sites and DOE sites where it was generated. This report examines the key attributes, challenges, and costs of the Yucca Mountain repository and the two principal alternatives to a repository that nuclear waste management experts identified: storing the nuclear waste at two centralized locations and continuing to store the waste on site where it was generated. GAO developed models of total cost ranges for each alternative using component cost estimates provided by the nuclear waste management experts. However, GAO did not compare these alternatives because of significant differences in their inherent characteristics that could not be quantified.

What GAO Found

The Yucca Mountain repository is designed to provide a permanent solution for managing nuclear waste, minimize the uncertainty of future waste safety, and enable DOE to begin fulfilling its legal obligation under the Nuclear Waste Policy Act to take custody of commercial waste, which began in 1998. However, project delays have led to utility lawsuits that DOE estimates are costing taxpayers about $12.3 billion in damages through 2020 and could cost $500 million per year after 2020, though the outcome of pending litigation may affect the government's total liability. Also, the administration has announced plans to terminate Yucca Mountain and seek alternatives. Even if DOE continues the program, it must obtain a Nuclear Regulatory Commission construction and operations license, a process likely to be delayed by budget shortfalls. GAO's analysis of DOE's cost projections found that a repository to dispose of 153,000 metric tons would cost from $41 billion to $67 billion (in 2009 present value) over a 143-year period until the repository is closed. Nuclear power rate payers would pay about 80 percent of these costs, and taxpayers would pay about 20 percent. Centralized storage at two locations provides an alternative that could be implemented within 10 to 30 years, allowing more time to consider final disposal options, nuclear waste to be removed from decommissioned reactor sites, and the government to take custody of commercial nuclear waste, saving billions of dollars in liabilities. However, DOE's statutory authority to provide centralized storage is uncertain, and finding a state willing to host a facility could be extremely challenging. In addition, centralized storage does not provide for final waste disposal, so much of the waste would be transported twice to reach its final destination. Using cost data from experts, GAO estimated the 2009 present value cost of centralized storage of 153,000 metric tons at the end of 100 years to range from $15 billion to $29 billion but increasing to between $23 billion and $81 billion with final geologic disposal. On-site storage would provide an alternative requiring little change from the status quo, but would face increasing challenges over time. It would also allow time for consideration of final disposal options. The additional time in on-site storage would make the waste safer to handle, reducing risks when waste is transported for final disposal. However, the government is unlikely to take custody of the waste, especially at operating nuclear reactor sites, which could result in significant financial liabilities that would increase over time. Not taking custody could also intensify public opposition to spent fuel storage site renewals and reactor license extensions, particularly with no plan in place for final waste disposition. In addition, extended on-site storage could introduce possible risks to the safety and security of the waste as the storage systems degrade and the waste decays, potentially requiring new maintenance and security measures. Using cost data from experts, GAO estimated the 2009 present value cost of on-site storage of 153,000 metric tons at the end of 100 years to range from $13 billion to $34 billion but increasing to between $20 billion to $97 billion with final geologic disposal.