U.S. Government's Environmental Liability
What We Found
The federal government’s environmental liability is vast and growing, and a number of agencies—especially the Departments of Energy and Defense, which bear the bulk of this liability—need to address environmental risks, and monitor and report on this liability.

Since our 2019 High-Risk Report, ratings in all five criteria remain unchanged.
Leadership commitment: partially met. As in 2019, federal agencies continue to partially meet this criterion. However, the Departments of Energy and Defense (DOE) and (DOD) have stalled in their efforts to focus more attention on their environmental liabilities.
Specifically, in the past 5 years, we have made 28 recommendations to DOE related to addressing and reducing its environmental liability, such as analyzing the root causes of its growing liability. DOE has yet to implement 26 of these 28 recommendations.
In addition, although DOE’s Office of Environmental Management developed a strategic vision in 2020 for the next decade of cleanup activities, it has not developed a strategic plan that incorporates the principles of risk-informed decision-making (i.e., an approach that helps agencies prioritize cleanup based on factors like cost and the risks to human health and the environment—which we outlined in September 2019). It also has yet to develop a method for tracking changes to its cleanup agreement requirements, as we reported in February 2019. Having these elements in place would better position DOE to effectively set priorities within and across its cleanup sites and direct its limited resources to address those priorities.
In November 2020, the DOD Inspector General found that DOD is unable to develop accurate estimates and account for environmental liabilities in accordance with accounting practices. Specifically, the Inspector General reported that DOD (1) is unable to substantiate the completeness and amount of its environmental liability estimate; and (2) has insufficient policies, procedures, and supporting documentation for developing and supporting its cost estimates, among other things.
Capacity: not met. Federal agencies have significant gaps in their ability to effectively address their current or future environmental liability. For instance, we found in March 2020 that federal agencies have identified at least 140,000 features at abandoned hardrock mines—such as unsecured tunnels and toxic waste piles—on lands managed by the Departments of Agriculture and the Interior. However, agency officials estimated there could be more than 390,000 abandoned hardrock mine features on federal lands that the agencies have yet to capture in their databases that could contribute to federal environmental liabilities. Federal and state officials cited availability of resources as a factor that limits efforts to address hazards at abandoned hardrock mines.
Similarly, we found in May 2020 that DOE’s Office of Legacy Management—which oversees long-term surveillance and maintenance at more than 100 former nuclear weapons production and energy research sites—has yet to plan for how to address challenges at some sites that may require new cleanup work outside the scope of the office’s expertise and resources.
We also found in November 2020 that DOE’s Office of Environmental Management has significant staffing shortages at its site office responsible for the Waste Isolation Pilot Plant in New Mexico. These shortages could affect the plant’s ability to remain on schedule for constructing additional disposal space. Also, any interruptions to waste shipments planned for disposal in the additional space could impair DOE’s ability to meet its cleanup milestones.
Action plan: not met. Neither DOE nor DOD has fully identified the causes of or developed a formal plan to address their growing environmental liability. DOE has taken initial steps toward a more risk-based approach to waste classification, such as initiating an effort in August 2020 to demonstrate the feasibility of its proposed interpretation of the statutory definition of high-level waste.
However, DOE continues to face challenges developing a cohesive action plan when addressing problems on its cleanup projects. For example, we found in February 2019 that DOE and its regulators have more than 70 agreements that contain hundreds of milestones for work at 16 cleanup sites, but that DOE has not conducted root cause analyses on missed or postponed milestones. Similarly, we found in September 2019 that DOE must treat more than a million gallons of waste at its Idaho National Laboratory, but initial testing of an on-site treatment facility revealed problems and DOE does not have a strategy or timeline to address them.
In October 2020, we reported that DOD had identified eight audit remediation priority areas to help guide and prioritize department-wide efforts. However, environmental liabilities is not one of the eight audit remediation priority areas identified, even though DOD’s Inspector General reported in 2020 that financial controls over environmental liabilities were lacking.
In addition, the lack of clarity about some cleanup standards may make it more difficult for federal agencies to develop plans. For example, the Environmental Protection Agency does not regulate certain emerging contaminants in drinking water, even as states have developed such standards. DOD and National Aeronautics and Space Administration (NASA) officials told us it is difficult to develop cleanup plans in the context of a varied and uncertain regulatory framework. While agencies may have to address stricter state standards, federal regulations would establish a regulatory floor for planning purposes.
Monitoring: not met. DOE and DOD do not have the information they need to monitor the effectiveness of their actions to address their environmental liabilities. DOE continues to struggle to develop reliable cost estimates and schedules for its cleanup efforts.
For example, we found in December 2019 that DOE’s Office of Environmental Management does not consistently track expenditures for cleanup activities across its three gaseous diffusion plants, which impedes its ability to develop reliable cost estimates. DOE’s 2019 report to Congress on the status of the fund to clean up these plants was based on outdated data and underestimates cleanup costs by about $20 billion.
In addition, we found in reviews conducted in 2019 and 2020 that DOE’s cost and schedule estimates for several cleanup projects were unreliable, which affects the accuracy of reported liabilities.
Additionally, the DOD Inspector General’s November 2020 financial audit found that DOD has not implemented a department-wide environmental liabilities calculation methodology. As a result of this lack of controls, DOD changed its estimated date for having a corrected environmental liability estimate from fiscal year 2021 to fiscal year 2025. In contrast, NASA—which holds less than 1 percent of the U.S. government’s environmental liabilities—tracks its environmental liability through a database of ongoing and potential future remediation projects, which includes information on estimated costs and uncertainties.
Demonstrated progress: not met. The federal government’s environmental liability, driven largely by DOE’s cleanup costs, continues to grow (see figure 8). DOE has made progress at some sites and is at or near completion for several important cleanup projects—such as the construction of the Salt Waste Processing Facility at the Savannah River Site which has been under construction for nearly 16 years.
In addition, DOE contracted with a federally funded research and development center, which issued a report in October 2019 on options for treating supplemental low-activity waste at the Hanford Site. We previously found that, if given authority by Congress to manage this waste as other than high-level waste, DOE could potentially save billions of dollars by using alternate treatment methods. In a December 2020 report, DOE acknowledged that it could save up to $230 billion by taking these actions that we have recommended.
However, DOE continues to face significant cost and schedule challenges with other projects and activities, such as the Waste Treatment Plant construction project at the Hanford Site. This cleanup project, which is DOE’s largest and most expensive, began in 2000 and has cost more than $11 billion to date. Since work stopped on much of the facility in 2012 to address technical challenges, DOE has spent $752 million (as of fiscal year 2018), mostly to preserve and maintain the site, and another $400 million pursuing alternatives. However, DOE has not used the best available methods to determine which alternative to pursue.
Similarly, DOD’s liability has remained largely unchanged in recent years despite DOD spending billions on environmental cleanup projects. DOE and DOD need to do more to demonstrate progress toward fully identifying, reporting, and developing a plan to address their environmental liabilities.
Figure 8: U.S. Government’s Environmental Liability, Fiscal Years 2015-19

The federal government's environmental liability will likely continue to grow even as billions are spent each year on cleanup efforts. For fiscal year 2019, the federal government's estimated environmental liability was $595.4 billion—up from $212 billion in fiscal year 1997 (the total liability for fiscal year 2020 was unavailable at the time this report was published). We added this area to our High-Risk List in 2017.
DOE is responsible for the largest share of the liability ($512 billion in fiscal year 2020), which is related primarily to retrieving, treating, and disposing of nuclear and hazardous waste. DOD is responsible for the second-largest share ($75 billion in fiscal year 2020), which is related primarily to environmental cleanup and restoration activities at or near its current and former installations. The remaining liability is shared among other agencies, including the Departments of Agriculture, Interior, Transportation, and Veterans Affairs, and NASA.
DOE’s liability grew by $7 billion in fiscal year 2020, primarily due to adjustments for inflation. Even with the increase, however, DOE’s cleanup responsibilities may be underestimated because government accounting standards for environmental liabilities only require agencies to report liability costs that can be reasonably estimated.
As of December 2020, 38 of our recommendations related to this high-risk area—of which 22 were made since 2019—had not been implemented. Of these recommendations, 31 pertain to either DOE or DOD and include the following:
- DOE should develop a program-wide strategy for implementing its cleanup agreements and a framework for incorporating risk-informed decisions.
- DOE should conduct root cause analyses of missed or postponed milestones.
- DOD should address deficiencies in its ability to substantiate the completeness and amount of its environmental liability estimate.
Congressional Actions Needed
Congress should consider clarifying DOE’s authority at the Hanford site to determine whether portions of the supplemental low-activity waste can be managed as other than high-level waste. Providing clear authority to DOE may allow it to use alternative waste treatment approaches to treat the Hanford Site’s supplemental low-activity waste, which could reduce certain risks by neutralizing the waste faster and save tens of billions of dollars.
