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Hazardous Waste Cleanup: Numbers of Contaminated Federal Sites, Estimated Costs, and EPA's Oversight Role

GAO-15-830T Published: Sep 11, 2015. Publicly Released: Sep 11, 2015.
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What GAO Found

The Departments of Agriculture (USDA), the Interior, Defense (DOD), and Energy (DOE) have identified thousands of contaminated and potentially contaminated sites on land they manage but do not have a complete inventory of sites, in particular, for abandoned mines. GAO reported in January 2015 that USDA had identified 1,491 contaminated sites and many potentially contaminated sites. However, USDA did not have a reliable, centralized site inventory or plans and procedures for completing one, in particular, for abandoned mines. For example, officials at USDA's Forest Service estimated that there were from 27,000 to 39,000 abandoned mines on its lands—approximately 20 percent of which may pose some level of risk to human health or the environment. GAO also reported that Interior had an inventory of 4,722 sites with confirmed or likely contamination. However, Interior's Bureau of Land Management had identified over 30,000 abandoned mines that were not yet assessed for contamination, and this inventory was not complete. DOD reported to Congress in June 2014 that it had 38,804 sites in its inventory of sites with contamination. DOE reported that it has 16 sites in 11 states with contamination.

These four departments reported allocating and spending millions of dollars annually on environmental cleanup and estimated future costs in the hundreds of millions of dollars or more in environmental liabilities. Specifically:

  • GAO reported in January 2015 that, in fiscal year 2013, USDA allocated over $22 million to environmental cleanup efforts and reported in its financial statements $176 million in environmental liabilities to address 100 sites.
  • GAO reported in January 2015 that Interior in fiscal year 2013 allocated about $13 million for environmental cleanup efforts and reported $192 million in environmental liabilities in its financial statements to address 434 sites.
  • In July 2010, GAO reported that DOD spent almost $30 billion from 1986 to 2008 across all environmental cleanup and restoration activities at its installations. In its fiscal year 2014 Agency Financial Report , DOD reported $58.6 billion in total environmental liabilities.
  • DOE reported receiving an annual appropriation of almost $5.9 billion in fiscal year 2015 to support cleanup activities. In 2014, DOE estimated its total liability for environmental cleanup at almost $300 billion.

As part of maintaining the list of contaminated and potentially contaminated federal sites, the Environmental Protection Agency (EPA) compiled 2,323 federal sites that may pose a risk to human health and the environment, as of August 2015, according to EPA officials. EPA is responsible for ensuring that federal agencies assess these sites for contamination and has established 18 months as a reasonable time frame for agencies to complete a preliminary assessment. However, in March 2009, GAO reported that according to EPA officials, some agencies, such as DOD, may take 2 to 3 years to complete an assessment and that EPA does not have independent authority under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) to enforce a timeline for completing the preliminary assessment. In March 2009, GAO suggested that Congress consider amending CERCLA section 120 to authorize EPA to require agencies to complete preliminary assessments within specified time frames.

Why GAO Did This Study

The federal government owns over 700 million acres of land. Some of this land—which is primarily managed by USDA, Interior, DOD, and DOE—is contaminated with hazardous waste from prior uses, such as landfills and mining.

To respond to problems caused by improper disposal of hazardous substances in the past, in 1980, Congress passed CERCLA, also known as Superfund. Among other things, CERCLA requires owners and operators of hazardous waste sites to notify the federal EPA—which manages the Superfund program—of the existence of their facilities, as well as known, suspected, or likely releases of hazardous substances.

This testimony focuses on (1) numbers of contaminated and potentially contaminated federal sites for four departments; (2) spending and estimates of future costs for cleanup at these federal sites; and (3) EPA's role in maintaining the list of contaminated and potentially contaminated federal sites and ensuring that preliminary assessments of such sites are complete. This testimony is based on prior GAO reports issued from March 2009 through March 2015.


GAO is making no new recommendations. Previously, GAO made numerous recommendations to ensure that contaminated sites were identified and assessed, and some of these recommendations have not been fully implemented. GAO will continue to monitor implementation.

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ContaminationEnvironmental cleanupsEnvironmental monitoringForest managementHazardous substancesHealth hazardsInteragency relationsInventoriesLand managementLandfillsMilitary facilitiesMiningPollutionPollution controlRadioactive waste disposalReporting requirementsCost estimates