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National Environmental Policy Act: Little Information Exists on NEPA Analyses

GAO-14-369 Published: Apr 15, 2014. Publicly Released: Apr 15, 2014.
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What GAO Found

Governmentwide data on the number and type of most National Environmental Policy Act (NEPA) analyses are not readily available, as data collection efforts vary by agency. NEPA generally requires federal agencies to evaluate the potential environmental effects of actions they propose to carry out, fund, or approve (e.g., by permit) by preparing analyses of different comprehensiveness depending on the significance of a proposed project's effects on the environment—from the most detailed Environmental Impact Statements (EIS) to the less comprehensive Environmental Assessments (EA) and Categorical Exclusions (CE). Agencies do not routinely track the number of EAs or CEs, but the Council on Environmental Quality (CEQ)—the entity within the Executive Office of the President that oversees NEPA implementation—estimates that about 95 percent of NEPA analyses are CEs, less than 5 percent are EAs, and less than 1 percent are EISs. Projects requiring an EIS are a small portion of all projects but are likely to be high-profile, complex, and expensive. The Environmental Protection Agency (EPA) maintains governmentwide information on EISs. A 2011 Congressional Research Service report noted that determining the total number of federal actions subject to NEPA is difficult, since most agencies track only the number of actions requiring an EIS.

Little information exists on the costs and benefits of completing NEPA analyses. Agencies do not routinely track the cost of completing NEPA analyses, and there is no governmentwide mechanism to do so, according to officials from CEQ, EPA, and other agencies GAO reviewed. However, the Department of Energy (DOE) tracks limited cost data associated with NEPA analyses. DOE officials told GAO that they track the money the agency pays to contractors to conduct NEPA analyses. According to DOE data, its median EIS contractor cost for calendar years 2003 through 2012 was $1.4 million. For context, a 2003 task force report to CEQ—the only available source of governmentwide cost estimates—estimated that a typical EIS cost from $250,000 to $2 million. EAs and CEs generally cost less than EISs, according to CEQ and federal agencies. Information on the benefits of completing NEPA analyses is largely qualitative. According to studies and agency officials, some of the qualitative benefits of NEPA include its role in encouraging public participation and in discovering and addressing project design problems that could be more costly in the long run. Complicating the determination of costs and benefits, agency activities under NEPA are hard to separate from other required environmental analyses under federal laws such as the Endangered Species Act and the Clean Water Act; executive orders; agency guidance; and state and local laws.

Some information is available on the frequency and outcome of NEPA litigation. Agency data, interviews with agency officials, and available studies show that most NEPA analyses do not result in litigation, although the impact of litigation could be substantial if a single lawsuit affects numerous federal decisions or actions in several states. In 2011, the most recent data available, CEQ reported 94 NEPA cases filed, down from the average of 129 cases filed per year from calendar year 2001 through calendar year 2008. The federal government prevails in most NEPA litigation, according to CEQ and legal studies.

Why GAO Did This Study

NEPA requires all federal agencies to evaluate the potential environmental effects of proposed projects—such as roads or bridges—on the human environment. Agencies prepare an EIS when a project will have a potentially significant impact on the environment. They may prepare an EA to determine whether a project will have a significant potential impact. If a project fits within a category of activities determined to have no significant impact—a CE—then an EA or an EIS is generally not necessary. The adequacy of these analyses has been a focus of litigation.

GAO was asked to review issues related to costs, time frames, and litigation associated with completing NEPA analyses. This report describes information on the (1) number and type of NEPA analyses, (2) costs and benefits of completing those analyses, and (3) frequency and outcomes of related litigation. GAO included available information on both costs and benefits to be consistent with standard economic principles for evaluating federal programs, and selected the Departments of Defense, Energy, the Interior, and Transportation, and the USDA Forest Service for analysis because they generally complete the most NEPA analyses. GAO reviewed documents and interviewed individuals from federal agencies, academia, and professional groups with expertise in NEPA analyses and litigation. GAO's findings are not generalizeable to agencies other than those selected.

This report has no recommendations. GAO provided a draft to CEQ and agency officials for review and comment, and they generally agreed with GAO's findings.

For more information, contact Anne-Marie Fennell at (202) 512-3841 or

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