# Judicial Review and the National Environmental Policy Act (NEPA)

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URL: https://www.frixlaw.com/law-library/documents/crs%3AR48717

## Record

- **Collection:** Congressional research report
- **Document type:** Reports
- **Published:** September 19, 2025
- **Citation:** R48717

## Text

Judicial Review and the National
Environmental Policy Act (NEPA)
September 19, 2025

Congressional Research Service
https://crsreports.congress.gov
R48717

SUMMARY

Judicial Review and the National
Environmental Policy Act (NEPA)

R48717
September 19, 2025
Kristen Hite

Legislative Attorney
The National Environmental Policy Act (NEPA) is one of the most frequently litigated federal
environmental statutes. NEPA is also one of the most broadly applicable federal environmental
statutes, with over 100,000 actions taken by the federal government each year subject to NEPA.
Enacted in 1969, NEPA generally requires federal agencies to integrate environmental
considerations into their decisionmaking processes. Under NEPA, agencies evaluate the
significance of environmental effects of major federal actions that are discretionary in nature. Actions subject to NEPA
include federal permits and licenses.

Federal courts have long allowed plaintiffs to challenge an agency’s compliance with NEPA under the Administrative
Procedure Act (APA). NEPA claims are commonly reviewed under the APA’s arbitrary-and-capricious standard based on
allegations that the agency action was arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law.
Some of the more frequently litigated issues include allegations that an agency failed to prepare NEPA documentation,
mischaracterized the significance of an action’s environmental impact, and failed to adequately consider relevant information
or comments about a proposed action. If an agency’s NEPA review is challenged under the arbitrary-and-capricious standard
under the APA, courts generally review the agency’s administrative record and determine whether the agency was
unreasonable or unsupported in its analysis or otherwise violated the law. While most NEPA-related litigation falls under the
APA, NEPA itself allows a project sponsor to seek judicial review of an agency’s alleged failure to comply with statutory
deadlines for completing NEPA documentation. Other environmental statutes may include judicial review provisions that
broadly allow a court to review agency actions, including NEPA-related decisions.
A court typically has broad latitude to order a spectrum of remedies when it finds an agency violated the law with respect to
NEPA. Courts typically tailor any relief ordered to fact-specific circumstances particular to the case in question. In cases
involving NEPA, such relief may include declaring an agency action unlawful, remanding the disputed action to the agency,
vacating (i.e., nullifying) all or part of an agency decision, and issuing an injunction. While courts can typically choose which
remedy to issue, courts have recognized that vacatur is the “ordinary” remedy for an APA violation. For example, courts
typically vacate an action if an agency fails to conduct a NEPA review prior to acting, or violates a procedural obligation that
casts “serious doubt” over an agency’s decision. In other instances, courts may remand a NEPA matter without vacatur.
Injunctions are a less common remedy for NEPA violations and must satisfy criteria—including the significance of harm,
balance of equities, and the public interest—in the event a judge were to consider granting injunctive relief.

Congressional Research Service

Judicial Review and the National Environmental Policy Act (NEPA)

Contents
Introduction ..................................................................................................................................... 1
Statutory and Regulatory Background ............................................................................................ 2
Administrative Framework ....................................................................................................... 2
Environmental Review Under NEPA ........................................................................................ 3
Judicial Review Authorities ...................................................................................................... 5
Administrative Procedure Act ............................................................................................. 6
Enforcing NEPA Deadlines to Prepare an EA or EIS ......................................................... 7
Deputizing Federal Actors: Waiver of Sovereign Immunity ............................................... 8
Considerations for Judicial Review of NEPA Litigation ................................................................. 8
Agency Discretion and Deference in Arbitrary-and-Capricious Cases ..................................... 9
Standing .................................................................................................................................. 10
Exhaustion ................................................................................................................................ 11
Statute of Limitations ............................................................................................................... 11
Common Issues in NEPA Litigation .............................................................................................. 12
Is a NEPA Review Required? .................................................................................................. 12
Is the Action Reviewable as a Final Major Federal Action? ............................................ 12
Is the Action Exempt from NEPA Due to Competing Authority?..................................... 13
Does New Activity Warrant Additional Analysis? ............................................................ 13
Did the Agency Properly Apply a Categorical Exclusion? ..................................................... 14
Did the Agency Adequately Analyze Environmental Impacts? .............................................. 15
Did the Agency Reasonably Determine the Appropriate Scope of Impacts? .................... 16
Can the Agency Substantiate Its Determination of Whether Impacts Are
Significant? .................................................................................................................... 17
Did the Agency Consider a Reasonable Set of Alternatives?.................................................. 18
Did the Agency Follow Appropriate Procedures for Consultation? ........................................ 19
Remedies in NEPA Litigation........................................................................................................ 19
Declaratory Relief ................................................................................................................... 20
Remand ................................................................................................................................... 20
Vacatur .................................................................................................................................... 20
Injunctive Relief ...................................................................................................................... 22
Considerations for Congress.......................................................................................................... 23

Contacts
Author Information........................................................................................................................ 24

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Judicial Review and the National Environmental Policy Act (NEPA)

Introduction
The National Environmental Policy Act (NEPA), enacted in 1969, generally requires federal
agencies to integrate environmental considerations into their decisionmaking processes.1 NEPA
directs agencies to use interdisciplinary approaches in considering environmental effects and, for
specified actions, requires a “detailed statement” about an action’s significant effects on the
human environment.2 Agencies must take a “hard look” at a covered action, consider alternative
options, and issue a detailed description of effects (environmental impact statement or EIS) when
a “reasonably foreseeable” impact may significantly affect the quality of the human
environment.3 Because this requirement applies to a wide range of federal actions—including
both the government’s own activities and its decisions to allow or to fund other parties’
activities—NEPA plays a significant role in the administration of many federal programs.4
Over the past five decades, the federal courts have been instrumental in guiding agency
compliance with NEPA. The courts review NEPA-related claims amid an evolving statutory and
regulatory landscape. The statute historically operated at more of a framework level and has seen
considerable engagement from all branches of government in recent years. Congress amended the
statute in 2023 and 2025.5 During that same time period, federal courts issued a number of
prominent opinions on NEPA, including the first Supreme Court case in two decades to address
the scope of NEPA reviews.6 In 2025, the Council on Environmental Quality (CEQ)—tasked by
Congress with oversight of NEPA’s implementation—rescinded implementing regulations
governing how agencies implement NEPA, deferring to individual agencies on how to implement
NEPA.7 To date, federal agencies have responded in varying degrees with updates to their
approaches to NEPA implementation.8 Agencies’ changes to NEPA procedures are themselves
1

Pub. L. No. 91–161, 83 Stat. 852 (1970) (codified as amended at 42 U.S.C. §§ 4321–4347). For a general overview of
NEPA, see CRS In Focus IF11549, The Legal Framework of the National Environmental Policy Act (2021).
2 42 U.S.C. § 4332.
3 Id.; id. §§ 4336(b)(1), 4336e(6).
4 See id. § 4336e(10) (defining major Federal action as one that an agency determines is “subject to substantial Federal
control and responsibility,” subject to certain exclusions).
5 Pub. L. No. 118–5, 137 Stat. 38 (2023); Pub. L. No. 119–21, 139 Stat. 157 (2025).
6 In November 2024, the U.S. Court of Appeals for the D.C. Circuit declared that President Carter’s 1977 executive
order mandating the Council on Environmental Quality (CEQ) to issue regulations binding on all federal agencies
exceeded the President’s statutory authority. Marin Audubon Soc’y v. Fed. Aviation Admin., 121 F.4th 902 (D.C. Cir.
2024). However, a subsequent majority concurring en banc declined to extend that reasoning, Marin Audubon Soc’y. v.
Fed. Aviation Admin., No. 23-1067, 2025 WL 374897, at *1 (D.C. Cir. Jan. 31, 2025) (Srinivasan, J., concurring). In
2025, the Supreme Court issued an opinion clarifying that agencies have substantial discretion in defining the scope of
impacts analyzed during a NEPA review and did not address the authority of CEQ to issue regulations, Seven Cnty.
Infrastructure Coal. v. Eagle County, 145 S. Ct. 1497 (2025). For a general discussion of the Seven County ruling, see
CRS Legal Sidebar LSB11333, “Deference Squared”: Supreme Court Limits NEPA’s Scope and Courts’ Reach in
Seven County Infrastructure Coalition, by Kristen Hite (2025).
7 Id. § 4344(3) (establishing CEQ’s duty to review and appraise federal programs and activities in the context of NEPA
and make recommendations to the President thereto); NEPA Implementing Regulations Revisions Phase 2, 89 Fed.
Reg. 35442 (May 1, 2024); Removal of NEPA Implementing Regulations, 90 Fed. Reg. 10610 (Feb. 25, 2025)
(amending subchapter A of chapter V in title 40 of the Code of Federal Regulations by removing and reserving parts
1500, 1501, 1502, 1503, 1504, 1505, 1506, 1507, and 1508); Memorandum from Katherine Scarlet, Chief of Staff,
CEQ, to Heads of Fed. Dep’ts & Agencies 1 (Feb. 19, 2025) [hereinafter CEQ Memo], https://ceq.doe.gov/docs/ceqregulations-and-guidance/CEQ-Memo-Implementation-of-NEPA-02.19.2025.pdf [https://perma.cc/HU63-R9LA]. See
also CRS In Focus IF12960, Council on Environmental Quality Rescinds NEPA Regulations: Legal and Policy
Considerations, by Heather McPherron and Kristen Hite (2025).
8 See, e.g., National Environmental Policy Act, 90 Fed. Reg. 29632 (July 3, 2025) (Dep’t of Agriculture); National
Environmental Policy Act Implementing Regulations, 90 Fed. Reg. 29498 (July 3, 2025) (Dep’t of the Interior).

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typically subject to judicial review, including recission of regulations and other changes that may
potentially limit or otherwise affect judicial review of NEPA determinations.
Most NEPA-related legal complaints are brought under the Administrative Procedure Act (APA),
as NEPA does not contain a broad judicial review provision addressing challenges to agencies’
actions under the statute. The APA provides broad authority for plaintiffs to challenge final
agency actions, including administrative reviews and permitting decisions.9 A narrower provision
in NEPA itself allows a project sponsor to seek judicial review of an agency’s alleged failure to
comply with certain statutory deadlines.10 Additionally, some statutes have general judicial review
provisions that broadly allow a court to review agency actions, including environmental reviews
under NEPA. For example, the Natural Gas Act vests the federal appellate courts with exclusive
jurisdiction to review an agency order covered by the Natural Gas Act, which may include a
NEPA review.11
This report focuses on the role of the federal courts in reviewing agency compliance with NEPA.
First, the report provides an overview of the relevant statutory and regulatory framework. Next, it
discusses how judicial review works in the NEPA context. Finally, the report provides an
overview of select issues that arise during litigation or tend to generate controversy about NEPA.

Statutory and Regulatory Background
Administrative Framework12
NEPA establishes a procedural framework for federal agencies to consider environmental impacts
when undertaking major federal actions. It requires agencies to evaluate whether a proposed
action is likely to have significant environmental effects and, if so, to document those effects and
consider reasonable alternatives.13 NEPA does not mandate which decisions agencies must make
or require them to select the most environmentally protective alternative. Rather, NEPA requires
agencies to conduct thorough analyses before making final decisions. In the words of the
Supreme Court, NEPA “merely prohibits uninformed—rather than unwise—agency action.”14
NEPA also created CEQ in the Executive Office of the President to provide oversight of NEPA’s
implementation, among other duties.15
In 1978, CEQ issued its first NEPA-implementing regulations and also directed federal agencies
to establish their own agency-specific procedures consistent with CEQ regulations while
reflecting agency-specific statutory requirements, regulations, and guidance.16 While CEQ has
historically provided regulations intended to standardize federal agencies’ approaches to
implementing NEPA, courts have recently questioned CEQ’s authority to issue binding
9 5 U.S.C. §§ 701–706.
10 42 U.S.C. § 4336a(g)(3). An agency that determines that it is unable to meet a statutory deadline may extend it for

“only so much additional time as is necessary,” in consultation with any applicant, if applicable. Id. § 4336a(g)(2).
11 15 U.S.C. § 717r.
12 CRS Analysts Heather McPherron and Omar Hammad contributed to portions of this section.
13 42 U.S.C. § 4332(C).
14 Robertson v. Methow Valley Citizens Council, 490 U.S. 332, 351 (1989).
15 42 U.S.C. § 4344(3) states that “it shall be the duty and function of the Council . . . to review and appraise the
various programs and activities of the Federal Government in the light of the policy set forth in subchapter I of [NEPA]
for the purpose of determining the extent to which such programs and activities are contributing to the achievement of
such policy, and to make recommendations to the President with respect thereto.”
16 National Environmental Policy Act—Regulations, 43 Fed. Reg. 55978, 56002–03 (Nov. 29, 1978).

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regulations.17 In January 2025, President Trump issued an executive order instructing CEQ to
propose rescinding its NEPA regulations and provide new guidance for NEPA implementation.18
On February 25, 2025, CEQ published an interim final rule to remove all of its NEPAimplementing regulations effective April 11, 2025.19 CEQ also directed federal agencies to revise
or establish their own NEPA procedures in consultation with CEQ within twelve months to align
with the 2023 NEPA amendments adopted in the Fiscal Responsibility Act (Pub. L. No. 118-5).20
CEQ further advised agencies to continue adhering to their existing NEPA practices and
procedures while adjusting for consistency with the amended statute.21 In July 2025, a number of
federal agencies rescinded or updated their NEPA regulations and issued new directives for
implementing NEPA.22

Environmental Review Under NEPA
NEPA requires that federal policies,
regulations, and public laws must be
interpreted and administered in
accordance with the statute “to the fullest
extent possible.”23 To determine whether
NEPA applies to a proposed action, an
agency must assess whether the action
qualifies as a major federal action and, if
so, whether its environmental impacts

NEPA and Federal Permitting
NEPA establishes procedural requirements for federal
decisionmaking. It mandates that federal agencies evaluate a
proposed action’s potential significant environmental
impacts. NEPA provides inputs to federal decisions. While
completion of a NEPA review does not automatically grant
or deny project approval, it may be a prerequisite for an
agency to finalize a federal decision to issue a permit.
Federal permitting, by comparison, typically regulates
nonfederal actors by requiring that they obtain specific
authorizations from regulatory agencies to proceed with
project activities. An agency decision to approve or
authorize a proposed course of action (e.g., issuing permits,
licensing, or granting rights-of-way across federal lands) is
often subject to NEPA. Even after an agency approves an
authorization, a federal permit alone may not be sufficient
for a project to proceed. For example, permits may also be
required at the state or local level before a project may
proceed.

17 In November 2024, the U.S. Court of Appeals for the D.C. Circuit declared that President Carter’s 1977 executive

order mandating CEQ to issue regulations binding on all federal agencies exceeded the President’s statutory authority.
Marin Audubon Soc’y v. Fed. Aviation Admin., 121 F.4th 902 (D.C. Cir. 2024). In February 2025, the U.S. District
Court for the District of North Dakota invalidated CEQ’s 2024 regulations based in part on the fact that they exceeded
statutory authority. Iowa v. CEQ, 765 F. Supp. 3d 859 (D.N.D. 2025), vacated and appeal dismissed by, No. 25-1641,
2025 WL 2205808 (8th Cir. July 29, 2025); see also CRS Legal Sidebar LSB11260, Marin Audubon Society v. Federal
Aviation Administration: D.C. Circuit Challenges CEQ’s Authority to Issue NEPA Regulations, by Kristen Hite and
Abigail A. Graber (2025).
18 Exec. Order No. 14,154, 90 Fed. Reg. 8353, 8353–55 (Jan. 29, 2025).
19 Removal of NEPA Implementing Regulations, 90 Fed. Reg. 10610 (Feb. 25, 2025). See also CRS In Focus IF12960,
Council on Environmental Quality Rescinds NEPA Regulations: Legal and Policy Considerations, by Heather
McPherron and Kristen Hite (2025).
20 On February 19, 2025, CEQ issued guidance on the implementation of the interim final rule and Executive Order No.
14,154. CEQ Memo, supra note 7. The passage of the Fiscal Responsibility Act (FRA) (Pub. L. No. 118-5) in 2023
introduced statutory amendments to NEPA, codifying several procedural elements previously established only through
CEQ regulations. For further information on the amendments to NEPA as a result of the FRA, see CRS In Focus
IF12417, Environmental Reviews and the 118th Congress, by Kristen Hite (2023).
21 CEQ Memo, supra note 7, at 1.
22 See, e.g., Removal of Environmental Impact Analysis Process (EIAP) Regulation, 90 Fed. Reg. 28021 (July 1, 2025)
(to be codified in 32 C.F.R. pt. 989).
23 42 U.S.C. § 4332. NEPA, Pub. L. No. 91–190, 83 Stat. 852 (1970).

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will be significant.24 The steps an agency takes to identify and document a proposed action’s
environmental impacts, as well as to consider alternatives to the action and their anticipated
environmental impacts, are commonly referred to as environmental review. Agencies may also
incorporate other environmental laws into their environmental review processes. Environmental
review is typically one step in the federal permitting process. NEPA can also apply to other
agency actions beyond permitting. Additionally, other federal laws may independently impose
procedural or substantive requirements and require authorizations or permits particular to a given
resource.25
NEPA does not apply to actions that are exempted by statute or involve non-discretionary agency
functions, or where the preparation of an environmental document would conflict with another
provision of federal law.26
If a proposed agency action is subject to NEPA and qualifies as a major federal action, the agency
must evaluate its potential environmental impacts to determine the level of environmental review
required.27 The statutory text of NEPA generally dictates the contours of the environmental
review, informed by CEQ guidance, agency procedures, and court decisions.28 Depending on
whether the potential effects are or are not significant, agencies proceed in one of three ways:29
•

Environmental impact statement (EIS). An EIS is required if a proposed agency action
would have a “reasonably foreseeable significant effect on the quality of the human
environment.”30 An EIS is generally limited to 150–300 pages in length; generally has a
two-year deadline; and includes a detailed analysis of potential environmental impacts,
reasonable alternatives to the proposed action, inter-agency consultation, and public
input.31

•

Environmental assessment (EA). An EA sets forth the basis of the agency’s decision to
issue a finding of no significant impact (FONSI) or a determination that significant
impacts are likely, in which case the agency prepares an EIS.32An EA is required when a
proposed agency action not covered by a categorical exclusion is not expected to have a

24 42 U.S.C. § 4332(C).
25 E.g., Endangered Species Act, 16 U.S.C. §§ 1531–1544; National Historic Preservation Act, 54 U.S.C. §§ 300101–

307108.
26 42 U.S.C. § 4336(a). Further, a discretionary action refers to an action where a federal agency has the authority to
choose among different courses of action or decide whether or not to take the action at all, as opposed to an action
where the agency’s decisions are guided by a statutory or regulatory mandate. CEQ, A CITIZEN’S GUIDE TO NEPA:
HAVING YOUR VOICE HEARD 4 (2021), https://ceq.doe.gov/docs/get-involved/citizens-guide-to-nepa-2021.pdf
[https://perma.cc/DTA2-FCK4].
27 42 U.S.C. § 4336(b).
28 For a general overview of NEPA’s environmental review process, see CRS In Focus IF12560, National
Environmental Policy Act: An Overview, by Kristen Hite and Heather McPherron (2025).
29 42 U.S.C. § 4336; id. § 4336(b)(1).
30 Id. § 4332(C).
31 Id. § 4336a. Page limits do not include citations or appendices; as necessary, timelines may be extended in
consultation with the applicant. Id. CEQ recently reported that the median time for EISs completed in 2024 was 2.2
years. CEQ, ENVIRONMENTAL IMPACT STATEMENT TIMELINES (2010−2024), at 1 (2025), https://ceq.doe.gov/docs/nepapractice/CEQ_EIS_Timeline_Report_2025-1-13.pdf [https://perma.cc/2DXL-G4PG]. Agencies are required to consult
with other federal agencies that have “jurisdiction by law or special expertise” and must further share inputs from
federal, state, and local agencies with the public, see 42 U.S.C. §§ 4332, 4336a. Additionally, while agency procedures
vary with respect to public input, every notice of intent to prepare an EIS must include an opportunity for public
comment on alternatives, impacts, and relevant information. Id. § 4336a(c).
32 42 U.S.C. § 4336a. Page limits are exclusive of citations and appendices; as necessary, timelines may be extended in
consultation with the applicant. Id.

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“reasonably foreseeable significant effect on the quality of the human environment, or if
the significance of such effects is unknown.”33 An EA is generally limited to seventy-five
pages in length and generally has a one-year deadline.34
•

Categorical exclusion (CE). CEs are categories of actions that a federal agency has
determined normally do not significantly affect the quality of the human environment.35
Agencies maintain lists of available CEs and in some cases may adopt another agency's
CE.36 When a federal agency determines that a proposed action falls within the scope of
an identified CE, it typically does not prepare an EA or EIS absent extraordinary
circumstances.37 Congress may also establish CEs.38

Historically, an estimated 95% or more of actions that are subject to NEPA result in CEs,
approximately 4% in EAs, and 1% or less in EISs.39

Judicial Review Authorities
Under certain circumstances, federal agency environmental reviews may be challenged in federal
court. Historically, fewer than 1% of federal actions subject to NEPA have been litigated.40 While
some have expressed concern that litigation increases the risk of project delays due to the

33 42 U.S.C. § 4336(b)(2).
34 Id. § 4336a. Page limits are exclusive of citations and appendices; as necessary, timelines may be extended in

consultation with the applicant. Id.
35 Id. § 4336e(1).
36
Id. § 4336c; CEQ, Categorical Exclusions: List of Federal Agency Categorical Exclusions (CE List), NEPA.GOV,
https://ceq.doe.gov/nepa-practice/categorical-exclusions.html [https://perma.cc/KK5P-NP3B] (last visited Aug. 12,
2025).
37 Many agencies maintain criteria or lists of conditions known as extraordinary circumstances that warrant special
consideration of impacts for proposed actions otherwise anticipated to have insignificant impacts. See, e.g., DEP’T OF
ENERGY, NATIONAL ENVIRONMENTAL POLICY ACT IMPLEMENTING PROCEDURES 23 (2025).
38 See, e.g., 16 U.S.C. § 6591e (directing the Forest Service to establish a categorical exclusion for mule deer and sage
grouse vegetation enhancement). Congress sometimes provides direction to agencies on CEs See, e.g., 42 U.S.C. §
15492 (creating a “rebuttable presumption” allowing the agency to apply a CE); 16 U.S.C. § 6592b (establishing a CE
for wildfire management subject to specific conditions); 49 U.S.C. § 304 (detailing conditions for applying a CE for
multimodal projects, including that extraordinary circumstances do not apply); see also CRS Report R48595,
Legislative Categorical Exclusions Under the National Environmental Policy Act (2025).
39 Update to the Regulations Implementing NEPA Procedural Provisions, 85 Fed. Reg. 43304, 43305 (July 16, 2020)
(estimating that agencies applied at least 100,000 CEs compared to several hundred EISs undertaken each year); U.S.
GOV’T ACCOUNTABILITY OFF., GAO-14-370, NATIONAL ENVIRONMENTAL POLICY ACT: LITTLE INFORMATION EXISTS ON
NEPA ANALYSES 7 (2014), https://www.gao.gov/assets/gao-14-370.pdf [https://perma.cc/BU4A-Q36B] (citing CEQ
statistics). CEQ has reported that out of 192,707 NEPA reviews associated with activities and projects funded between
2009 and 2011 by the American Recovery and Reinvestment Act of 2009, Pub. L. No. 111-5, 123 Stat. 115, 184,733
were completed using CEs, 7,133 were completed using EAs, and 841 required EISs. CEQ, THE ELEVENTH AND FINAL
REPORT ON THE NEPA STATUS AND PROGRESS FOR AMERICAN RECOVERY AND REINVESTMENT ACT OF 2009 ACTIVITIES
AND PROJECTS 4 (2011).
40 CEQ, NEPA LITIGATION SURVEYS 2001–2013, https://ceq.doe.gov/docs/ceq-reports/nepa-litigation-surveys-20012013.pdf [https://perma.cc/G58E-BTFZ] (identifying an average of 145 cases/year subject to litigation); 85 Fed. Reg. at
43305, 43309 & n.5, n.40 (July 16, 2020) (identifying over 100,000 NEPA actions annually). An analysis of the CEQ
NEPA Litigation data set found that roughly 1 in 450 NEPA decisions were litigated. See John Ruple & Kayla Race,
Measuring the NEPA Litigation Burden: A Review of 1,499 Federal Court Cases, 50 ENV’T L. 479 (2020). For context,
NEPA has been the most litigated of all environmental laws, see CEQ, FACT SHEET: MODERNIZING CEQ’S NEPA
REGULATIONS (2020), https://ceq.doe.gov/docs/laws-regulations/ceq-final-rule-fact-sheet-2020-07-15.pdf
[https://perma.cc/UG5R-8W5F].

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potential for a judge to order a project halted (a form of injunctive relief), others have suggested
that NEPA-related litigation delay concerns are “overblown.”41
Plaintiffs seeking to challenge agency NEPA reviews (or failures therein) can bring their
challenges in federal court. Many of these challenges are brought pursuant to the APA, which
provides a cause of action for challenges to final agency actions.42 The APA is a default statute
that applies in the absence of another statute providing judicial review for a particular agency
action. NEPA’s provision allowing a project sponsor to sue to enforce an agency deadline for
completing an EA or EIS is one such example.43 Other examples of more specific statutes
providing for review include the Natural Gas Act and the Air Tour Management Act of 2000.44
Unless a statute provides otherwise, a plaintiff filing a claim to challenge a federal agency’s
NEPA review (or lack thereof) typically files suit in federal district court, with cases decided by a
presiding judge as opposed to a jury.45

Administrative Procedure Act
Except where a more specific statute controls, the APA permits agency actions to be challenged in
federal district court. The APA generally establishes how courts review agency actions, including
the appropriate standards of review.46 Most commonly for NEPA, a plaintiff may ask a court to
“set aside” an agency action if it was “arbitrary, capricious, an abuse of discretion, or otherwise
not in accordance with law.”47 In such a situation, a court considers whether the agency action
was reasonable and reasonably explained.48 Additional bases for setting aside an agency action
include when an agency violates a statutory right or fails to follow a procedure required by law,
among others.49 By statute, an action may not be reviewed until it is final, so documents such as a

41 For more discussion of permitting litigation considerations, compare Michael Bennon & David Wilson, NEPA

Litigation over Large Energy and Transport Infrastructure Projects, 53 ENV’T L. REP. 10836 (2023) (identifying
litigation arising in 28% of select major transportation infrastructure projects requiring an EIS, of which 89% involved
a NEPA claim) with David E. Adelman et al., Dispelling the Myths of Permitting Reform and Identifying Effective
Pathways Forward, 55 ENV’T L. REP. 10038, 10041–42 (2025) (characterizing as a “myth” the notion that federal
permitting is the cause for most project delays and noting a 90% decline in the number of EISs prepared annually from
the 1970s to 2020s).
42 5 U.S.C. § 704.
43 See id. § 706; 42 U.S.C. § 4336a(g)(3).
44 15 U.S.C. § 717r; 49 U.S.C. § 40128(b)(5).
45 See 5 U.S.C. § 703; 28 U.S.C. § 1331. Some statutes specifically provide for direct review of an agency action in the
federal courts of appeals, bypassing district courts with further appeal available only directly to the United States
Supreme Court. E.g., 15 U.S.C. § 717r(d). Others expressly exempt an agency from NEPA compliance or otherwise
limit NEPA’s application. See, e.g., Ctr. for Biological Diversity v. Trump, 453 F. Supp. 3d 11 (D.D.C. 2020)
(declining to require NEPA compliance where a statute allowed the Department of Homeland Security to waive NEPA
requirements for border wall construction).
46 5 U.S.C. § 704. For more information on judicial review under the APA, see CRS Legal Sidebar LSB10558, Judicial
Review Under the Administrative Procedure Act (APA), by Jonathan M. Gaffney (2024); CRS Report R44699, An
Introduction to Judicial Review of Federal Agency Action, by Jared P. Cole (2016).
47 5 U.S.C. § 706; see also Marsh v. Or. Nat. Res. Council, 490 U.S. 360, 378 (1989) (explaining that an arbitrary-andcapricious review is a “searching and careful” factual inquiry based on a “narrow” standard of “whether the decision
was based on a consideration of the relevant factors and whether there has been a clear error of judgment.” (quoting
Citizens to Preserve Overton Park, Inc. v. Volpe, 401 U.S. 402, 416 (1971))). As a part of the judicial review process
under the APA, federal courts “decide all relevant questions of law, interpret constitutional and statutory provisions;
and determine the meaning or applicability of the terms of an agency action.” 5 U.S.C. § 706.
48 See Motor Vehicle Mfrs. Ass’n of United States, Inc. v. State Farm Mut. Auto. Ins. Co., 463 U.S. 29, 43, 103 (1983);
Seven Cnty. Infrastructure Coal. v. Eagle County, 145 S. Ct. 1497, 1511 (2025).
49 5 U.S.C. § 706.

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draft EIS typically cannot be challenged as violating the APA.50 When evaluating the action, a
judge reviews the whole applicable portion of the agency’s record, typically accepting the facts as
the agency has found them barring certain exceptions.51

Enforcing NEPA Deadlines to Prepare an EA or EIS
As amended in 2023, NEPA contains one provision that directly allows for judicial review,
available only to a project sponsor seeking to enforce statutory time limits for an agency to
prepare an EIS or EA.52 One of the first cases to consider this provision is Signal Peak Energy v.
Haaland, which concerned a proposed expansion of the Bull Mountain Mine in Montana.53 In
February 2024, Signal Peak Energy petitioned the U.S. District Court for the District of Columbia
to enforce NEPA’s two-year timeline for agencies to complete an EIS.54 In August 2024, the court
determined that the claim was “prudentially unripe.”55 The court reasoned that the government
could plausibly still make or extend the deadline, so it was premature to find a violation, and
further that the project sponsor was unlikely to suffer substantial immediate economic harm from
the delay.56 The agency subsequently issued an EIS in June 2025, resulting in the case being
dismissed.57 Prior to dismissal, conservation groups tried unsuccessfully to intervene in the
lawsuit. In rejecting their attempt, the court reasoned that NEPA’s provision allowing a court to
review EIS deadlines “does not appear to have been designed with conservation groups in
mind.”58 If other courts take the same approach, both environmental interests and project sponsors
may be unsuccessful in seeking to prospectively enforce NEPA’s deadlines for agencies to
complete an EIS (two years) or EA (one year). In other words, a project sponsor could seek
judicial review only once an agency has failed to meet that deadline.

50 Id. § 704; Bennett v. Spear, 520 U.S. 154, 178 (1997) (explaining that a “final” action is the consummation of an

agency’s decisionmaking affecting rights and obligations or other legal consequences). Examples of situations where
finality issues affected plaintiffs’ NEPA claims include Whitewater Draw Nat. Res. Conservation Dist. v. Mayorkas, 5
F.4th 997 (9th Cir. 2021) (affirming that lack of instructions on how to implement NEPA in an agency handbook did
not rise to a final agency action); Cnty. Comm’rs of Cnty. of Sierra v. U.S. Dep’t of the Interior, 614 F. Supp. 3d 944,
947, 953 (D.N.M. 2022) (dismissing a claim challenging a decision to transfer two individual wolves); see also
Driftless Area Land Conservancy v. Rural Utils. Serv., 74 F.4th 489, 495 (7th Cir. 2023) (finding that adoption of an
EIS without issuing a record of decision was insufficient to constitute final agency action for the purpose of challenging
the underlying decision).
51 5 U.S.C. § 706; see also Citizens to Preserve Overton Park, 401 U.S. at 415 (discussing de novo review of facts
when an adjudication involves inadequate factfinding resulting in an “unwarranted” agency decision as one of two
specific circumstances).
52 42 U.S.C. § 4336a(g)(3).
53 Signal Peak Energy, LLC v. Haaland, No. 24-cv-00366, 2024 WL 3887386 (D.D.C. Aug. 21, 2024).
54 Id. 42 U.S.C. § 4336a(g) provides that agencies generally complete an EIS within two years, which may be extended
if necessary to allow completion, “in consultation with the applicant.” 42 U.S.C. § 4336a(g)(3) allows a project sponsor
to petition a court to review an agency’s alleged failure to meet the deadline and to order a schedule for EIS
completion.
55 The court partially dismissed the claim and denied as moot Signal Peak Energy’s petition for a preliminary injunction
to enforce the two-year EIS deadline on the basis. Signal Peak Energy, 2024 WL 3887386, at *9. The doctrine of
prudential ripeness encourages courts to not prematurely decide abstract disagreements that are not yet fit for a judicial
decision where the parties will not suffer hardship if the court withholds consideration until an agency’s action is
sufficiently final. See Abbott Labs. v. Gardner, 387 U.S. 136, 148–49 (1967); Nat’l Treasury Emps. Union v. United
States, 101 F.3d 1423, 1431 (D.C. Cir. 1996).
56 Signal Peak Energy, 2024 WL 3887386, at *9–10.
57 Minute Order, Signal Peak Energy, LLC v. Haaland, No. 24-cv-00366 (D.D.C. July 3, 2025).
58 Signal Peak Energy, 2024 WL 3887386, at *6–7. The court allowed conservation groups to submit an amicus brief.
Id. at *7.

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Deputizing Federal Actors: Waiver of Sovereign Immunity
Certain statutes allow states or local authorities to assume responsibility for NEPA compliance in
limited circumstances.59 In those cases, federal law generally requires that any such nonfederal
authority expressly waive sovereign immunity and accept jurisdiction of the federal courts to
consider allegations of noncompliance.60 For example, the Federal Highway Administration and
the Department of Transportation have procedures available to sign a memorandum of
understanding allowing a state or local agency to assume responsibility for NEPA or broader
environmental review authority generally reserved to federal agencies.61 As of July 2025, seven
states had entered into such an agreement.62 In those cases, the nonfederal implementing authority
is required to accept jurisdiction in federal court for suits alleging violations of NEPA, and the
federal government may be immune from lawsuits.63 In such circumstances, the assigned
nonfederal implementing authority is held to the same standards of review under NEPA as if it
were a federal agency.64

Considerations for Judicial Review of NEPA
Litigation
A number of questions frequently arise with respect to how courts resolve NEPA disputes. Many
of these questions relate to principles that limit the availability of judicial review of agency
action.65 Some limitations are constitutional, while others are rooted in statute. In the context of
challenges to federal agencies’ NEPA reviews, some of the more commonly cited limitations for
permitting-related challenges are briefly discussed below. Other limitations include mootness and
statutory preclusion.66 As discussed above, Congress may further limit review of NEPA claims.
59

E.g., 23 U.S.C. §§ 326, 327 (allowing the Federal Highway Administration to assign states oversight of
environmental reviews including NEPA or CE decisions, respectively).
60 E.g., id. at § 327(c) (requiring a written agreement from a state consenting to federal court jurisdiction over
“compliance, discharge, and enforcement of any responsibility of the Secretary assumed by the State”).
61 Id.; 23 C.F.R. §§ 773.101–117 (2025); FED. HWY. ADMIN., ENVIRONMENTAL REVIEW TOOLKIT – NEPA ASSIGNMENT,
https://www.environment.fhwa.dot.gov/nepa/program_assignment.aspx [https://perma.cc/48Y6-TLP6] (last visited
Aug. 5, 2025).
62 FED. HWY. ADMIN., supra note 61. The seven states are Alaska, Arizona, California, Florida, Ohio, Utah, and Texas.
Nebraska was listed as “under consideration.” Id. Under a pilot program, the Federal Highway Administration may
elect to enter into a further agreement with two states that have a signed a memorandum of understanding to allow
substitution of state procedures for NEPA. See 23 U.S.C. § 330; Program for Eliminating Duplication of Environmental
Review, 85 Fed. Reg. 84213 (Dec. 28, 2020) (to be codified at 23 C.F.R. pts. 773, 778).
63 See, e.g., Bitters v. Fed. Hwy. Admin., No. 1:14-cv-01646-KJM-SMS, 2016 WL 159216, at *18 (E.D. Cal. Jan. 13,
2016) (reviewing California Department of Transportation’s compliance with NEPA); Salt Lake City Corp. v.
Shepherd, No. 2:23-CV-786, 2024 WL 2158128, at *3 (D. Utah May 14, 2024) (finding the federal government to be
shielded from suit by sovereign immunity).
64 See, e.g., Fath v. Tex. Dep’t of Transp., 924 F.3d 132 (5th Cir. 2018) (upholding Texas Department of
Transportation’s NEPA review based on Federal Highway Administration NEPA regulations and federal case law).
65 For an overview of judicial review of agency action and a discussion of limitations on the availability of judicial
review, see CRS Report R44699, An Introduction to Judicial Review of Federal Agency Action, by Jared P. Cole
(2016).
66 A case is moot if the controversy initially existing at the time the lawsuit was filed is no longer “live.” See, e.g.,
Native Village of Nuiqsut v. Bureau of Land Mgmt., 9 F.4th 1201 (9th Cir. 2021) (denying NEPA claim as moot where
oil and gas producer had completed a project following agency approval of winter drilling exploration activities after
all equipment had been demobilized, weather had warmed, and wells were capped). Statutory preclusion refers to a
provision in the APA specifying that the judicial review provisions do not apply if “statutes preclude judicial review.” 5
U.S.C. § 701(a)(1). While a modest set of statutes exclude specific actions or types of actions from judicial review
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Courts have also addressed what level of deference is appropriate when applying the arbitraryand-capricious standard of review to agency actions taken pursuant to NEPA.

Agency Discretion and Deference in Arbitrary-and-Capricious
Cases
The Supreme Court has observed that on matters of agency policymaking and factfinding
(including as applies to NEPA), the APA imposes a deferential standard of review; no similar
deference exists with respect to matters of statutory interpretation.67 In Seven County
Infrastructure Coalition v. Eagle County, the Supreme Court reiterated that the role of courts is
deferential and limited when evaluating agency NEPA reviews under the APA’s arbitrary-andcapricious standard.68 Particularly on factual matters such as evaluation of significant impacts,
courts have held that they should not substitute their judgment for that of the agency. Instead, a
court typically considers whether the agency action was reasonable and reasonably explained.69
Applying NEPA’s inherent “rule of reason,” courts have identified various factors for determining
whether an agency’s NEPA review may be found arbitrary and capricious.70 Many courts have
applied long-standing Supreme Court precedent in a NEPA-specific context, such as when an
agency has relied on factors Congress did not intend it to consider, “entirely failed” to consider an
important aspect of the problem, offered an explanation for its decision that runs counter to the
evidence before it, or is implausible beyond a mere difference in view or the product of agency
expertise.71 A court may also find an agency’s NEPA review was arbitrary and capricious if it
“failed to base its decision on consideration of the relevant factors” or made a “clear error in
judgment.”72
under NEPA, the exception is relatively uncommon and generally requires a “persuasive reason” to believe that
Congress intended to exclude a claim from judicial review. Bowen v. Mich. Acad. of Family Physicians, 476 U.S. 667,
670 (1986); see also Mass. Coal. for Immig. Reform v. U.S. Dep’t of Homeland Sec., 621 F. Supp. 3d 84, 98 (D.D.C.
2022) (finding review of alleged failure to conduct a NEPA review prior to instituting administrative closure in
immigration courts was not barred by a provision in the Immigration and Nationality Act excluding review of
immigration removal decisions themselves).
67 Seven Cnty. Infrastructure Coal., 145 S. Ct. 1497; Loper Bright Enters. v. Raimondo, 603 U.S. 369, 371, 392 (2024)
(citing 5 U.S.C. § 706(2)).
68 Seven Cnty. Infrastructure Coal., 145 S. Ct. 1497.
69 Id. at 1511 (citing Motor Vehicle Mfrs. Ass’n of United States, Inc. v. State Farm Mut. Auto. Ins. Co., 463 U.S. 29,
103 (1983)).
70 Seven Cnty. Infrastructure Coal., 145 S. Ct. at 1513; Dep’t of Transp. v. Pub. Citizen, 541 U.S. 752, 767 (2004); see
also Diné Citizens Against Ruining Our Env't v. Haaland, 59 F.4th 1016, 1029 (10th Cir. 2023) (specifying four ways
in which an agency’s NEPA review may be arbitrary and capricious). Courts may further apply a “substantial
evidence” standard to NEPA reviews, setting aside agency action under the APA only where it is supported by
substantial evidence. See, e.g., WildEarth Guardians v. U.S. Army Corps of Eng’rs, 429 F. Supp. 3d 1224, 1263
(D.N.M. 2019) (citing Forest Guardians v. U.S. Fish & Wildlife Serv., 611 F.3d 692, 704 (10th Cir. 2010)).
71 Motor Vehicle Mfrs. Ass’n, 463 U.S. at 43. For example, an agency “entirely failed” to consider an important element
of the analysis when it failed to consider greenhouse gas impacts or at least explain its reason for not doing so when
there were methods available for such a calculation. See Gulf v. Burgum, 775 F. Supp. 3d 455, 481 (D.D.C. 2025).
Another example is an “unexplained inconsistency” in analysis, see Montana Wildlife Fed’n v. Haaland, 127 F.4th 1,
36 (9th Cir. 2025). Courts may, however, uphold an agency’s review where it explained its choice of methodology for
calculating climate impacts. See Diné Citizens, 59 F.4th at 1043. But see Citizens Action Coal. of Indiana, Inc. v.
FERC, 125 F.4th 229, 241 (D.C. Cir. 2025) (upholding an agency’s choice of climate methodology).
72 For examples of how courts consider relevant factors in NEPA cases, see Am. Wild Horse Campaign v. Raby, No.
24-8055, 2025 WL 1933473, at *4 (10th Cir. July 15, 2025) (quoting New Mexico ex rel. Richardson v. Bureau of
Land Mgmt., 565 F.3d 683, 704 (10th Cir. 2009); Utah Env’t Cong. v. Troyer, 479 F.3d 1269, 1280 (10th Cir. 2007)).
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Standing
Article III of the Constitution limits the federal courts’ jurisdiction to adjudicating “cases” and
“controversies.”73 As part of this requirement, a litigant must have standing in order to invoke the
jurisdiction of a federal court. To establish standing, a plaintiff must demonstrate (1) an injury in
fact (2) that is fairly traceable to the challenged action (e.g., caused by an alleged statutory
violation) and (3) that can be remedied by a court.74 To meet the Article III injury threshold, a
plaintiff must allege that the agency’s action has harmed or will harm the plaintiff’s concrete
interest.75 Standing principles also prohibit courts from addressing alleged injuries that are
“generalized grievances,” as these do not present “cases” or “controversies” as required by Article
III.76
The Supreme Court has long recognized that a plaintiff alleging a procedural injury—including a
NEPA violation—may be subject to a modified standing requirement of demonstrating a concrete
interest in a legally recognized procedure.77 For example, in considering whether an alleged
injury falls within the “zone of interests” of NEPA,78 the Supreme Court has held that NEPA
protects a broad range of harms, including recreational or aesthetic enjoyment of the
environment.79 While NEPA does not reach purely economic injuries, plaintiffs who allege both
environmental and economic injuries may satisfy the “zone of interests” test.80 Additionally,

An example of an error in judgment is City of Los Angeles v. Fed. Aviation Admin., 63 F.4th 835, 851–52 (9th Cir.
2023) (finding a “fundamental error” where the agency failed to consider combined noise impacts from multiple pieces
of construction running simultaneously and had instead analyzed conditions as if only one machine were operating at
any given time).
73 U.S. CONST. art. III, § 2.
74 Friends of the Earth v. Laidlaw, 528 US 167, 180–81 (2000); Lujan v. Defenders of Wildlife, 504 U.S. 555, 560
(1992).
75 Defs. of Wildlife, 504 U.S. at 560 (applying imminent and concrete injury to a protected right as the general standard
for a plaintiff to establish standing).
76 Lexmark Int’l, Inc. v. Static Control Components, Inc., 572 U.S. 118, 127 n.3 (2014).
77 Id. at 572 & n.7 (recognizing procedural rights as “special” and applying a modified standing requirement applies to
a plaintiff with a concrete interest in a legally recognized procedural right “without meeting all the normal standards for
redressability and immediacy,” such as could be the case for a claim arising under NEPA if a plaintiff alleges an EIS
failed to consider future impacts to a nearby property in a pending permitting decision).
78 Ondrusek v. U.S. Army Corps of Eng’rs, 123 F.4th 720, 734 (5th Cir. 2024) (noting the redressability standard is
“not demanding” (citing Sierra Club v. FERC, 827 F.3d 59, 67 (D.C. Cir. 2016) and Defs. of Wildlife, 504 U.S. at 572
n.7). The Supreme Court previously described this requirement as part of its “prudential standing” doctrine, but in
Lexmark, recharacterized the requirement as a question of statutory interpretation. Lexmark Int’l., 572 U.S. at 127–28.
79 Lujan v Nat’l Wildlife Fed’n, 497 U.S. 871 (1990).
80 See, e.g., Maiden Creek Assoc. LP v. U.S. Dep’t of Transp., 823 F.3d 184, 195 (3d Cir. 2016) (“To accept NEPA
litigants whose interests accidentally overlap with the statute’s intended purpose would not only create a class of
plaintiffs far larger than Congress originally intended, it also would serve to distort the effect of NEPA itself.”); Solar
Energy Indus. Ass’n v. FERC, 80 F.4th 956, 991 (9th Cir. 2023) (allowing a NEPA suit even if a plaintiff’s interest is
primarily economic so long as there as the economic injuries are “causally related to an act within NEPA’s embrace” or
if there is a separate environmental interest (quoting Port of Astoria. v. Hodel, 595 F.2d 467, 476 (9th Cir. 1979))).
Plaintiffs who assert environmental injuries, but whose primary motive for bringing suit is economic interest, also
“routinely satisfy” this test; however, plaintiffs who assert purely economic injuries do not. Compare Mass. Coal. for
Immig. Reform v. U.S. Dep’t of Homeland Sec., 621 F. Supp. 3d 84, 94 (D.D.C. 2022) (finding sufficient connection
to an environmental interest to meet a relaxed zone of interest test due to NEPA being a procedural statute) with
Louisiana v. Dep’t of Homeland Sec., 726 F. Supp. 3d 653, 688 (E.D. La. 2024) (dismissing case due to lack of
standing after plaintiffs failed the “zone of interest” test under NEPA where injuries were “purely economic”).

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courts have found that a NEPA violation could be remedied if the agency could conceivably
change its position on whether or how to proceed with the underlying action.81
Organizations often bring cases on behalf of their members, including NEPA-based challenges.
They may satisfy the standing requirements if (1) at least one of the members has standing, (2)
the interests that the organization seeks to protect are germane to its purposes, and (3) neither the
claim nor the type of relief sought would require the individual members to actively participate in
the litigation.82

Exhaustion
Some statutes have explicit requirements that bar a claim if a plaintiff has not first exhausted
administrative options, such as by participating in an agency’s administrative process for raising
objections to a permitting matter.83 The Supreme Court has determined the APA has no express
exhaustion requirement.84 Even where a statute is silent, courts generally expect a plaintiff to
provide notice to and raise their issues with the relevant agency during the appropriate comment
period for the proposed agency action, and if a plaintiffs does not do so, a judge has some degree
of discretion to bar a later claim involving those issues.85 In other situations, a court may follow
the Supreme Court’s suggestion that flaws in an EA or EIS “might be so obvious that there is no
need for a commentator to point them out specifically in order to preserve its ability to challenge
a proposed action.”86

Statute of Limitations
A statute of limitations is a provision in law specifying a time by which a plaintiff must file a
lawsuit. If the specific statute at issue is silent, courts have generally defaulted to a six-year limit
for a plaintiff who challenges a permitting action under the APA.87 Some permitting-related
statutes include limitations affecting timelines for review on certain NEPA claims. For example,
judicial review of some transportation projects is limited to 150 days after notice that the permit,

81 Ondrusek, 123 F.4th at 734.
82 Sierra Club v. Morton, 405 U.S. 727, 739–40 (1972); Sierra Club v. FERC, 827 F.3d 59, 65 (D.C. Cir. 2016) (citing

Hunt v. Wash. State Apple Advert. Comm’n, 432 U.S. 333, 343 (1977)); Mountain Cmtys. for Fire Safety v. Elliott, 25
F.4th 649, 6554 & n.6 (9th Cir. 2022) (citing Friends of the Earth, Inc. v. Laidlaw Env't Servs. (TOC), Inc., 528 U.S.
167, 169 (2000).
83 See, e.g., 16 U.S.C. § 6515(c).
84 Darby v. Cisneros, 509 U.S. 137, 146–47 (1993).
85 See, e.g., Dep’t of Transp. v. Pub. Citizen, 541 U.S. 752, 764−765 (2004); Vt. Yankee Nuclear Power Corp. v. Nat.
Res. Def. Council, 435 U.S. 519, 553 (1978). But see Mulgrew v. U.S. Dep’t of Transp., 750 F. Supp. 3d 171, 215
(S.D.N.Y. 2024) (“[A]n issue is exhausted if it was included in a comment on the EA—regardless of who submitted the
comment.”).
86 Pub. Citizen, 541 U.S. at 765. See also, e.g, Friends of Tims Ford v. Tenn. Valley Auth., 585 F.3d 955, 964 (6th Cir.
2009) (allowing a NEPA challenge to proceed because the agency had not shown why the “deficient” EIS “was not so
obvious that [plaintiffs] needed to comment to preserve its right to appeal”); Mulgrew, 750 F. Supp. 3d at 215
(permitting a claim to proceed based on constructive notice of a matter raised by a third party).
87 28 U.S.C. § 2401(a) states that “every civil action commenced against the United States shall be barred unless the
complaint is filed within six years after the right of action first accrues.” The Supreme Court held in 2024 that, for the
purposes of facial challenges to agency actions, a claim accrues when an injury to the plaintiff occurs, rather than at the
time the agency action becomes final. Corner Post, Inc. v. Bd. of Governors of the Fed. Reserve Sys., 603 U.S. 799
(2024); see also CRS Legal Sidebar LSB11197, Corner Post and the Statute of Limitations for Administrative
Procedure Act Claims, by Benjamin M. Barczewski and Jonathan M. Gaffney (2024).

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license, or approval is final.88 For large infrastructure and other projects covered under FAST-41,
Congress has imposed a maximum two-year statute of limitations on authorizations.89

Common Issues in NEPA Litigation
NEPA litigation involves a wide range of agencies and raises issues involving agency choices and
determinations. This section provides an overview of selected issues raised in NEPA litigation
that may be of interest to Congress.

Is a NEPA Review Required?
Is the Action Reviewable as a Final Major Federal Action?
NEPA applies if an agency’s proposed activity is a major federal action.90 To qualify, the
proposed action must be “subject to substantial Federal control and responsibility” and not
subject to any statutory exceptions.91 For example, NEPA excludes actions with no or minimal
federal funding and those with no or minimal federal involvement where the agency cannot
control the outcome of the project.92
If an agency fails to initiate any environmental review for an action covered by NEPA, plaintiffs
may challenge that in court, provided they can show the proposed action qualifies as a final
agency action subject to the requirements of NEPA. For example, there may be questions about to
what extent NEPA is triggered in discrete agency actions associated with a project implemented
in multiple phases that require assorted federal approvals over the course of the project.93 In
deciding whether any particular agency action for such a project requires NEPA review, courts
may consider whether the agency action would irreversibly commit federal resources in
furtherance of the proposed action as a standard to determine whether the agency activity is a
qualifying action under NEPA.94 Even where an action qualifies as a major federal action under
NEPA, there may be disputes over whether a proposed action is reviewable in court as a final
agency action under the APA. To have a cause of action under the APA, the challenged action
must also be considered a final agency action.95
88 E.g., 23 U.S.C. § 139(l).
89 42 U.S.C. § 4370m-6; id. § 4370m(6) (defining “covered project”); see also 42 U.S.C. § 4370m (3) defining

authorization as “any license, permit, approval, finding, determination, or other administrative decision issued by an
agency and any interagency consultation that is required or authorized under Federal law in order to site, construct,
reconstruct, or commence operations of a covered project administered by a Federal agency or, in the case of a State
that chooses to participate in the environmental review and authorization process in accordance with section 4370m–
2(c)(3)(A) of this title, a State agency.” “Authorization” includes both permits and federal actions related to the
permitting process). The two-year time limit for FAST-41’s statute of limitations begins upon publication in the
Federal Register, and the time period may be shorter if so specified in federal law. Id. at § 4370m-6(1).
90 Id. §§ 4332(c), 4336e(10).
91 Id. § 4336e(10).
92 See id. § 4336e(10)(B).
93 See, e.g., N. Alaska Env’t Ctr. v. U.S. Dep’t of the Interior, 983 F.3d 1077 (9th Cir. 2020).
94 Id. at 1086 (discussing circumstances under which a federal lease could trigger NEPA based on whether it would
allow or preclude surface-disturbing activity); Ctr. for Biological Diversity v. U.S. Dep’t of the Interior, 563 F.3d 466,
480 (D.C. Cir. 2009).
95 5 U.S.C. § 704; Bennett v. Spear, 520 U.S. 154, 178 (1997) (explaining that a “final” action is the consummation of
an agency’s decisionmaking affecting rights and obligations or other legal consequences). Examples of situations
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Is the Action Exempt from NEPA Due to Competing Authority?
Courts must occasionally address what happens when an agency is faced with a potential conflict
or overlap between NEPA and other statutory mandates. As the Supreme Court has held, NEPA
was not intended to repeal any other statute by implication.96 Thus, when “a clear and
unavoidable conflict in statutory authority exists, NEPA must give way.”97 Such a conflict may
exist, for example, if the period for implementing a statutory mandate is too short for an agency
to complete environmental review under NEPA.98 Some courts have also held that NEPA does not
apply when an agency’s actions to comply with other statutes are “functional[ly] equivalent” to
NEPA.99 This analysis requires courts to assess, on a case-by-case basis, what an agency must
take into account when complying with other statutes, especially with respect to environmental
effects or considerations.100

Does New Activity Warrant Additional Analysis?
When considering new activity related to a prior action that already has documented analysis of
environmental impacts or when supplementing earlier NEPA analysis, an agency may refer back
to the existing analysis and incorporate it by reference or take a multiphased approach such as
starting with a broader strategic level review and then supplementing on a project-specific basis
with analysis limited to new conditions or information (tiering).101 Sometimes this analysis is
undertaken as a supplemental EA or EIS. Other times, an agency incorporates earlier NEPA
analysis by reference. In some cases, an agency may issue supplemental analysis when a court
remands environmental review to an agency to correct a deficiency in its initial analysis.102
where finality issues affected plaintiffs’ NEPA claims include Whitewater Draw Nat. Res. Conservation Dist. v.
Mayorkas, 5 F.4th 997 (9th Cir. 2021) (affirming that lack of instructions on how to implement NEPA in an agency
handbook did not rise to a final agency action); Cnty. Comm’rs of Cnty. of Sierra v. U.S. Dep’t of the Interior, 614 F.
Supp. 3d 944, 947, 953 (D.N.M. 2022) (dismissing a claim challenging a decision to transfer two individual wolves);
see also Driftless Area Land Conservancy v. Rural Utils. Serv., 74 F.4th 489, 495 (7th Cir. 2023) (finding that adoption
of an EIS without issuing a record of decision was insufficient to constitute final agency action for the purpose of
challenging the underlying decision); Citizens for Clean Energy v. U.S. Dep’t of the Interior, 384 F. Supp. 3d 1264,
1281 (D. Mont. 2019) (clarifying that a decision to not prepare a NEPA document is reviewable as a final agency
action).
96 United States v. SCRAP, 412 U.S. 669, 694 (1973); see also 42 U.S.C. § 4332(C) (stating that environmental review
is not required “where compliance would be inconsistent with other statutory requirements”).
97 Flint Ridge Dev. Corp. v. Scenic Rivers Ass’n of Okla., 426 U.S. 776, 788 (1976).
98 Id. at 788–89 (finding it “inconceivable” that an agency could comply with NEPA within the thirty-day deadline for
issuance of statement of record under Disclosure Act).
99 Prutehi Litekyan: Save Ritidian v. U.S. Dep’t of Airforce, 128 F.4th 1089, 1117 (9th Cir. 2025) (quoting Alabama ex
rel. Siegelman v. EPA, 911 F.2d 499, 504 (11th Cir. 1990)).
100 See, e.g., Env’t Def. Fund, Inc. v. EPA, 489 F.2d 1247 (D.C. Cir. 1973) (holding the Federal Insecticide, Fungicide,
and Rodenticide Act to be the functional equivalent of NEPA because the statute required the agency to take
environmental effects into account and consider public comments about such effects); see also Pac. Legal Found. v.
Andrus, 657 F.2d 829, 834 (6th Cir. 1981) (discussing lower court practice applying the “functional equivalent” test).
101 See, e.g., Theodore Roosevelt Conservation P’ship v. Salazar, 616 F.3d 497, 512 (D.C. Cir. 2010) (noting that
projects implemented over the course of several decades could understandably be subject to a change of conditions, but
tiering enables agencies to refer back to older analysis so long as the effects are reasonably considered, even if
methodologies have improved); see also 42 U.S.C. § 4336b (authorizing reliance on prior programmatic analysis within
five years of publication barring new circumstances or information or later so long as the agency reevaluates the
analysis and underlying assumptions to verify the earlier analysis “remains valid”).
102 See, e.g., Ctr. for Biological Diversity v. U.S. Bureau of Land Mgmt., 141 F.4th 976, 990–91 (9th Cir. 2025)
(addressing the adequacy of an agency’s supplemental EIS prepared in response to Sovereign Iñupiat for a Living
Arctic v. Bureau of Land Mgmt., 555 F. Supp. 3d 739, 770, 805 (D. Alaska 2021) (invalidating the agency’s initial
NEPA analysis concerning the Willow Project)).

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Additionally, a plaintiff may claim that an agency failed to conduct an appropriate supplemental
environmental review. These disputes tend to center on situations where existing NEPA analysis
exists and new information or circumstances arise.103 For example, supplemental analysis could
be warranted for proposed changes to agency salvage logging operations following a wildfire
unless the agency’s environmental review already factored in post-fire conditions.104
Alternatively, if additional action is contemplated where an existing NEPA analysis has already
been completed and there has been no material change in circumstances or information, even a
one-paragraph explanation may be sufficient to defend an agency’s decision to reference back to
existing analysis (tiering) so long as the agency has documented that it determined that no new
information or circumstances warranted further consideration.105

Did the Agency Properly Apply a Categorical Exclusion?
When an agency applies a CE to a specific action, it does not prepare an EA or EIS. Where an
agency determines that site-specific conditions (extraordinary circumstances) exist that could
result in more significant impacts from an action that would otherwise qualify for a CE, the
agency may decline to apply a CE to the action. The presence of an extraordinary circumstance
does not automatically restrict application of the CE, but it can lead an agency to evaluate
whether impacts are anticipated to be significant such that it would be appropriate to prepare an
EA or EIS.106 Agency CE procedures generally require the agency to consider extraordinary
circumstances, but the same may not always be true of congressionally created CEs. At least one
court has ruled that the Forest Service was not required to consider extraordinary circumstances
before applying a congressionally created CE where the statute did not mandate such
consideration.107
When an agency relies on a CE to determine that further NEPA analysis is not required, plaintiffs
may argue that the agency improperly used a CE for a specific action or may challenge the
creation of the CE itself. Whether an agency’s decision to create or apply a CE was arbitrary or
capricious is a fact-specific determination where courts consider whether an agency acted
rationally and followed the appropriate procedures to do so.108
In disputes involving challenges to specific uses of CEs, plaintiffs have raised different theories.
For example, some plaintiffs have alleged that an agency failed to follow its own procedures to

103 See, e.g., No Mid-Currituck Bridge-Concerned Citizens v. N.C. Dep’t of Transp., 60 F.4th 794, 805 (4th Cir. 2023)

(upholding agency’s decision not to supplement in part because the agency determined that new information reinforced
a previous analysis).
104 See, e.g., Earth Island Inst. v. Elliott, 318 F. Supp. 3d 1155, 1184 (E.D. Cal. 2018) (differentiating an obligation to
supplement following new conditions potentially present following a forest fire from a supplemental review that relied
on existing post-fire NEPA analysis).
105 Gulf v. Burgum, 775 F. Supp. 3d 455, at 488–90 (D.D.C. 2025).
106 See, e.g., Los Padres ForestWatch v. U.S. Forest Serv., No. 23-55801, 2024 WL 4750504, at *1 (9th Cir. Nov. 12,
2024) (upholding the agency’s NEPA review because the agency followed applicable NEPA procedures in considering
whether any extraordinary circumstances pertaining to the proposed action would result in significant impacts for the
proposed action prior to applying the CE); Int’l Soc’y for Prot. of Mustangs & Burros v. U.S. Dep’t of Agric., No. CV22-08114-PHX-SPL, 2022 WL 3588223, at *12 (D. Ariz. July 28, 2022) (upholding the agency’s decision to apply a
CE notwithstanding the extraordinary circumstance of endangered species present because the agency showed its
proposed action would be beneficial to the endangered species present).
107 Wild Watershed v. Hurlocker, 961 F.3d 1119, 1127 (10th Cir. 2020).
108 See, e.g., San Luis Obispo Mothers for Peace v. U.S. Nuclear Reg. Comm’n, 100 F.4th 1039, 1058 (9th Cir. 2024)
(determining agency followed its own procedures and reasonably applied its CE).

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use a CE.109 In other cases, plaintiffs have argued that an agency improperly relied on multiple
CEs to avoid preparing an EIS.110 While many plaintiffs have alleged that an agency improperly
relied on a CE and should have instead prepared an EIS, at least one plaintiff unsuccessfully sued
an agency for opting to prepare an EIS when it allegedly could have opted to apply a CE.111
Courts may consider whether an agency validly created a CE (sometimes referred to as
“adopting” a CE) or appropriately adopted another agency’s CE. For example, in Sierra Club v.
Bosworth, the plaintiffs alleged that the Forest Service violated the APA by categorically
excluding all fuel reduction projects of up to 1,000 acres and burn projects of up to 4,500 acres.112
The U.S. Court of Appeals for the Ninth Circuit concluded that the Forest Service’s CE violated
the APA because the Service (1) collected data only to justify, rather than assess, the
appropriateness of a CE; (2) failed to explain why the cumulative effect of each project would not
have significant environmental effects; and (3) failed to specify criteria for each type of project
that would ensure a project had no significant environmental effects.113 Additionally, as amended
in 2023, NEPA has also allowed agencies to apply another agency’s CE provided they follow the
appropriate procedures and consults with the “host” agency about the appropriateness of applying
the exclusion in question.114 Some plaintiffs have challenged these applications in court.115

Did the Agency Adequately Analyze Environmental Impacts?
A court may evaluate whether an agency’s NEPA review was arbitrary or capricious based on an
alleged failure to consider certain impacts or to fully consider the weight of the impacts reviewed.
As discussed in more detail below, if an agency makes a decision to move forward with an action
without preparing an EIS—whether by applying a CE, issuing a FONSI, or failing to prepare any
document—plaintiffs can challenge the agency’s decision, asserting that the action would result
in significant impacts and therefore requires preparation of an EIS. In other instances, an agency
may prepare an EIS where plaintiffs allege the analysis failed to consider a key element of the
analysis or an alternative. In these cases, courts generally review the agency’s analysis under the
APA to determine whether the agency’s decision to limit or exclude consideration of particular
effects was arbitrary or capricious. In Seven County Infrastructure Coalition, the Supreme Court
underscored that courts must afford agencies substantial deference in determining whether an
agency reasonably exercised its discretion in determining the appropriate scope and contents of
an EIS.116 In particular, the Court clarified that under this standard, the “only role” for courts is to
109 See, e.g., Oak Ridge Env’t Peace All. v. Perry, 412 F. Supp. 3d 786, 845 (E.D. Tenn. 2019) (invalidating multiple

decisions to apply CEs due to agency’s failure to follow its own regulations in considering extraordinary
circumstances); U.S. Citrus Sci. Council v. U.S. Dep’t of Agric., 312 F. Supp. 3d 884, 915 (E.D. Cal. 2018) (resolving
a disputed application of an agency regulation in favor of the agency’s decision to apply a CE).
110 Compare, e.g., Los Padres, No. CV 22-2781-JFW (SKX), 2023 WL 5667533, at *11 (C.D. Cal. July 19, 2023),
aff'd, 2024 WL 4750504 (9th Cir. Nov. 12, 2024) (upholding the Forest Service’s use of multiple CEs in a single
proposed action where each was separately considered to apply to the overall proposed action and discussing how other
courts have allowed this practice) with Friends of the Inyo v. U.S. Forest Serv., 103 F.4th 543, 556 (9th Cir. 2024)
(invalidating agency action that impermissibly combined CEs in a manner that failed to take a hard look at how each
individual CE applied to the proposed action).
111 See Town of Ogden Dunes v. U.S. Dep’t of the Interior, No. 2:20-CV-34-TLS-JEM, 2022 WL 715549, at *11 (N.D.
Ind. Mar. 10, 2022).
112 510 F.3d 1016 (9th Cir. 2007).
113 Id. at 1026–33.
114 Fiscal Responsibility Act of 2023, Pub. L. No. 118-5, sec. 321(b), § 109, 137 Stat. 10, 43–44.
115 See, e.g., Plaintiffs’ Motion for Summary Judgement, Sierra Club, v. U.S. Dep’t of the Interior, No. 4:24-cv-04651JST (N.D. Cal. Apr. 28, 2025), Dkt. No. 37.
116 Seven Cnty. Infrastructure Coal. v. Eagle County, 145 S. Ct. 1497, 1512 (2025).

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“confirm that the agency has addressed environmental consequences and feasible alternatives as
to the relevant project.”117

Did the Agency Reasonably Determine the Appropriate Scope of Impacts?
Disputes regarding the appropriate scope of analysis can arise, including whether anticipated
effects are too attenuated from a proposed action to include in an EIS or EA. As the Supreme
Court explained in Seven County Infrastructure Coalition, an agency should follow a “rule of
reason” rooted in its statutory authority to determine the appropriate scope of a NEPA analysis.118
This analysis built on Department of Transportation v. Public Citizen, in which the Court ruled
that the Federal Motor Carrier Safety Administration did not violate NEPA by not considering the
environmental effects related to a decision beyond the agency’s (and NEPA’s) purview: increased
entry of trucks from Mexico into the United States, which had been authorized by the President
(who is not subject to NEPA) as an outcome of a trade dispute.119 Additionally, the Court has
clarified that a NEPA analysis should focus on the “project at hand” as opposed to broader effects
associated with separate future projects.120
Another set of cases involves allegations that an agency failed to consider all relevant indirect
effects arising from a proposed action. The Supreme Court has acknowledged that the extent to
which an agency must include indirect effects in its NEPA analysis is a matter of agency
discretion.121 In Seven County Infrastructure Coalition, the Court overturned a D.C. Circuit
decision that had relied in part on a series of cases ruling that indirect effects, such as greenhouse
gas impacts, must be considered where relevant to the underlying authority.122 While the Court
acknowledged that environmental effects that “might extend outside the geographic territory of
the project or might materialize later in time”—“so-called indirect effects”—“may fall within
NEPA,” the Court asserted that “courts should defer to agencies’ decisions about where to draw
the line” as to “how far to go in considering indirect environmental effects from the project at
hand.”123 Ultimately, the Court in Seven County upheld the agency’s decision to include some
degree of greenhouse gas impacts in its NEPA analysis in part due to its determination that many
of the effects concerned pertained to separate projects, and further, the APA’s arbitrary-andcapricious standard mandates that courts defer to an agency’s determination on what effects to
include or exclude.124

117 Id. at 1511 (quoting Strycker’s Bay Neighborhood Council, Inc. v. Karlen, 444 U.S. 223, 227 (1980)).
118 Id. at 1513.
119 Dep’t of Transp. v. Pub. Citizen, 541 U.S. 762, 767–68 (2004); see Ala. Wilderness League v. Jewell, 788 F.3d

1212, 1225–26 (9th Cir. 2015).
120 Seven Cnty. Infrastructure Coal., 145 S. Ct. at 1515–16.
121 Id. at 1512–13.
122 Id. at 1518; Eagle County v. Surface Transp. Bd., 82 F.4th 1152, 1178 (D.C. Cir. 2023) (citing, e.g., Sierra Club v.
FERC, 867 F.3d 1357, 1374 (D.C. Cir. 2017) (“[G]reenhouse-gas emissions are an indirect effect of authorizing this
project, which FERC could reasonably foresee, and which the agency has legal authority to mitigate.”)).
123 Seven Cnty. Infrastructure Coalition, 145 S. Ct. at 1513, 1515.
124 Id. at 1520 (Sotomayor, J., concurring) (explaining how the agency included consideration of greenhouse gas
impacts in its environmental analysis); id. at 1516 (specifying that the agency was not required to ask another agency to
consider climate impacts to Gulf Coast communities associated with a separate project); id., at 1517 (“[E]ven if the
reviewing court in such a case might think that NEPA would support drawing a different line, a court should defer to an
agency so long as the agency drew a reasonable and ‘manageable line.’” (quoting Dep’t of Transp. v. Pub. Citizen, 541
U.S. 752, 767 (2004)).

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Can the Agency Substantiate Its Determination of Whether Impacts Are
Significant?
Agencies and plaintiffs sometimes disagree about whether an agency should have prepared an
EIS in instances when an agency applied a CE or prepared an EA and then issued a FONSI
documenting the determination that a proposed action would not have significant effects. Courts
consistently require that an agency must take a “hard look” at a proposed action’s potential effects
in order to determine whether impacts are significant, though the specific details are often factand case-specific.125 For example, some plaintiffs have argued an agency improperly segmented a
project by dividing it into discrete, separate actions to “avoid a more thorough consideration of
the impacts of the entire project” or parsed a proposal into subcomponents that could be
completed via some combination of EAs and/or CEs in order to stay below the “significance”
threshold.126 Others have alleged (to varying degrees of success) that an agency lacked enough
data to make a reasoned decision about whether effects were significant.127 Other disputes involve
questions about an agency’s reliance on certain types of information, such as whether an agency
inappropriately relied on outdated information or circumstances substantially changed before the
agency finalized its decision (and failed to update its analysis).128
In some situations, an agency may face litigation over its decision to prepare an EA and issue a
FONSI where impacts could have been significant but for mitigation measures intended to
address anticipated impacts.129 This is sometimes known as a mitigated FONSI.130 Agencies may
also include mitigation measures as a condition for proceeding with a proposed action when
issuing an EIS or authorizing use of a CE. Such mitigation measures may be enforceable in
court.131

125 Robertson v. Methow Valley Citizens Council, 490 U.S. 332, 350 (1989); see also Friends of the Floridas v. U.S.

Bureau of Land Mgmt., 746 F. Supp. 3d 1039, 1151 & n.48 (D.N.M. 2024) (discussing how courts apply a “hard look”
requirement for NEPA and the APA).
126 Tinian Women Ass’n v. U.S. Dep’t of the Navy, 976 F.3d 832, 838 (9th Cir. 2020); see, e.g., Sierra Club v. U.S.
Army Corps of Eng’rs, No. 2:20-CV-396-LEW, 2025 WL 961432, at *22 (D. Me. Mar. 31, 2025).
127 Compare Sierra Club, 2025 WL 961432, at *22 (declining to hold agency to standard of “perfection” in considering
best available evidence and upholding a NEPA review where agency adequately considered information available to it)
with Cascadia Wildlands v. Adcock, No. 6:22-CV-01344-MTK, 2025 WL 1194191, at *8 (D. Or. Apr. 24, 2025)
(finding it was unreasonable for an agency to knowingly undertake field surveys only after the NEPA review had been
completed unless it was for a landscape-level analysis where subsequent field-level analysis was planned as a part of a
separate NEPA review).
128 See, e.g., Gulf v. Burgum, 775 F. Supp. 3d 455, 483 (D.D.C. 2025) (finding it was unreasonable for agency to refuse
to consider new information resulting from changed conditions resulting from enactment of new legislation affecting
the proposed action). Whether an agency relied on outdated information for its current analysis is different than
analysis of whether an agency violated the law by declining to supplement existing NEPA analysis where new
information has become available. See, e.g., WildEarth Guardians v. Bernhardt, 423 F. Supp. 3d 1083, 1102 (D. Colo.
2019) (upholding agency decision not to supplement notwithstanding new information).
129 See, e.g., O’Reilly v. U.S. Army Corps of Eng’rs, 477 F.3d 225, 234 (5th Cir. 2007) (invalidating a mitigated
FONSI following preparation of an EA that provided “only cursory detail” in describing the extent of the mitigation
measures and how they would reduce the significance of impacts).
130 Previously, CEQ regulations in 40 C.F.R. § 1501.6 set forth conditions under which agencies could issue a mitigated
FONSI. Some agencies adopted their own procedures, which may still be in effect although CEQ regulations have
since been revoked, see Removal of NEPA Implementing Regulations, 90 Fed. Reg. 10610 (Feb. 25, 2025). NEPA
itself is silent on the use of a mitigated FONSI.
131 See, e.g., Mulgrew v. U.S. Dep’t of Transp., 750 F. Supp. 3d 171, 217 (S.D.N.Y. 2024) (upholding agency FONSI
based on application mitigation measures for congestion pricing); Protect Our Cmtys. Found. v. LaCounte, 939 F.3d
1029 (9th Cir. 2019) (addressing mitigation measures intended to protect golden eagles as conditions in an EIS
pertaining to construction and operation of wind turbines).

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Did the Agency Consider a Reasonable Set of Alternatives?
NEPA requires agencies to consider alternatives to their proposed actions as part of the
environmental review process.132 Courts and CEQ have referred to this requirement as the “heart”
of the environmental review.133 Agencies need not analyze every possible option; rather, “the
concept of alternatives must be bounded by some notion of feasibility.”134 Thus, agencies must
exercise “common sense” when determining which proposals to include in an EIS; courts will not
find an EIS insufficient “simply because the agency failed to include every alternative device and
thought conceivable by the mind of man.”135 While some specific authorities limit consideration
of alternatives, agencies typically have broad latitude under NEPA to decide what alternatives to
include or exclude in a NEPA analysis. For example, courts have found it reasonable for an
agency to limit alternatives analysis to a preferred option and a no-action option.136 Additionally,
if there was opportunity for public comment in preparation of a NEPA document, courts typically
dismiss claims alleging the agency failed to consider an alternative if that argument was not
raised during the comment period.137
Challenges to an agency’s consideration of alternatives to the proposed action arise in a variety of
ways. Under the APA’s arbitrary-and-capricious standard, agencies are typically judged by
whether they considered a reasonable range of alternatives and explained their reasoning for
accepting or rejecting specific options.138 For example, in a decision that presaged Seven County
Infrastructure Coalition, the U.S. Court of Appeals for the First Circuit refused to find that the
Bureau of Land Management was arbitrary or capricious in its rejection of alternatives outside the
geographic area for a proposed lease, reasoning that activity beyond the planned area could be
considered as a separate project at a later date.139 Similarly, the D.C. Circuit has refused to require
the Federal Energy Regulatory Commission to consider the type of energy used in its alternatives
analysis where a state controlled the selection of energy sources.140 A court may, however, find

132 42 U.S.C. § 4332.
133 See, e.g., CEQ, A CITIZEN’S GUIDE TO THE NEPA 16 (2007), https://ceq.doe.gov/docs/get-

involved/Citizens_Guide_Dec07.pdf [https://perma.cc/UW2Y-2CJG]; Wyoming v. U.S. Dep’t of Agric., 661 F.3d
1209, 1243 (10th Cir. 2011); City of Carmel-By-The-Sea v. U.S. Dep’t of Transp., 123 F.3d 1142, 1155 (9th Cir.
1997); Citizens Against Burlington, Inc. v. Busey, 938 F.2d 190, 194 (D.C. Cir. 1991).
134 Vt. Yankee Nuclear Power Corp. v. Nat. Res. Def. Council, Inc., 435 U.S. 519, 551 (1978).
135 Id.
136 Earth Island Inst. v. U.S. Forest Serv., 87 F.4th 1054, 1065 (9th Cir. 2023) (citing N. Idaho Cmty. Action Network
v. U.S. Dep’t of Transp., 545 F.3d 1147, 1154 (9th Cir. 2008)); see also 16 U.S.C. § 6514 (allowing consideration of
only one alternative for covered hazardous fuels reduction projects); Friends of the Floridas v. U.S. Bureau of Land
Mgmt., 746 F. Supp. 3d 1039, 1175–76 (D.N.M. 2024) (accepting agency’s reasoned rejection of two alternatives
beyond the preferred action/no-action alternatives where the project proposal was “straightforward” and the proposed
alternatives met the stated purpose and need of the proposed action).
137 See, e.g., Earth Island Inst., 87 F.4th at 1063 (noting an exception for commenting on alternatives where an agency
has independent information available, but that was not the case here and plaintiffs made no effort to raise the matter
during the applicable comment period). For additional discussion of limitations based on failure to first raise a concern
directly with the agency, see discussion supra “Exhaustion.”
138 See, e.g., Hualapai Indian Tribe v. Haaland, 755 F. Supp. 3d 1165, 1193 (D. Ariz. 2024) (finding a NEPA violation
for failure of agency to at least consider including reasonable alternatives identified by plaintiff in public comments).
139 Seafreeze Shoreside, Inc. v. U.S. Dept. of the Int., 123 F.4th 1, 22 (1st Cir. 2024), cert. denied sub nom.,
Responsible Offshore Dev. v. Dep’t of the Interior, No. 24-966, 2025 WL 1287066 (U.S. May 5, 2025), and cert.
denied sub nom., Seafreeze Shoreside Inc. v. Dep’t of the Interior, No. 24-971, 2025 WL 1287076 (U.S. May 5, 2025).
140 Citizens Action Coal. of Ind., Inc. v. FERC, 125 F.4th 229, 239 (D.C. Cir. 2025).

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that the agency is arbitrary and capricious where it ignores consideration of any alternatives and
fails to explain why options submitted during public comment were not viable.141

Did the Agency Follow Appropriate Procedures for Consultation?
NEPA’s goals encourage informed agency decisionmaking and include certain public disclosure
and participation requirements.142 Since 2023, NEPA has required that an agency publicly
circulate a notice of intent to prepare an EIS.143 Additionally, an agency drafting an EIS must
obtain comments from federal agencies with “jurisdiction by law or special expertise with respect
to any environmental impact involved.”144 These comments—as well as any additional comments
and views of federal, state, and local agencies—must accompany the proposal through any
agency review processes, and are also made available to the President, CEQ, and the public.145
Agencies also engage with relevant tribal authorities and may also receive public comments
during this time.146 Whether or not an agency followed these procedures is generally reviewable
as a matter of law.147

Remedies in NEPA Litigation
A court typically has broad latitude to order a spectrum of remedies when it finds an agency
violated the law with respect to NEPA. In cases considering the validity of a permit or related
authorization, such relief could include declaring an agency’s NEPA or permitting action illegal,
remanding the disputed NEPA analysis to the agency for further consideration, vacating all or part
of a permitting decision, or further enjoining project activity.148

141 See, e.g., Hualapai Indian Tribe v. Haaland, 755 F. Supp. 3d 1165, 1193 (D. Ariz. 2024) (finding tribe’s proposed

alternatives for alternate oil well design options to be not “infeasible, ineffective, or inconsistent” with policy) (citing
Headwaters, Inc. v. Bureau of Land Mgt., Medford Dist., 914 F.2d 1174, 1181 (9th Cir. 1990)).
142 See 42 U.S.C. § 4332; Robertson v. Methow Valley Citizens Council, 490 U.S. 332, 333 (1989) (noting NEPA’s
EIS requirement and other procedures implement “sweeping policy goals by ensuring that agencies will take a ‘hard
look’ at environmental consequences and by guaranteeing broad public dissemination of relevant information”).
143 Fiscal Responsibility Act of 2023, Pub. L. No. 118-5, sec. 321(b), § 107(c), 137 Stat. 10, 41. Until April 2025, CEQ
regulations required agencies to circulate a draft EIS for public comment. See Exec. Order No. 14,154, 90 Fed. Reg.
8353 (Jan. 20, 2025); CEQ Memo, supra note 7; Removal of NEPA Implementing Regulations, 90 Fed. Reg. 10610
(Feb. 25, 2025).
144 42 U.S.C. § 4332(C)(v). Federal, state, tribal, and local cooperating agencies may contribute to the development of
the EIS, potentially including analysis or proposals such as mitigation measures related to the proposed action. Id.
145 Id.
146 Aside from scoping inputs (42 U.S.C. § 4336a(c)), NEPA itself does not explicitly require public comment on a
draft EIS. For decades, CEQ regulations required public input with a public comment period that typically lasted at
least forty-five days between the draft and final EIS across all iterations of their NEPA implementing regulations. See,
e.g., NEPA Implementing Regulations Revisions Phase 2, 89 Fed. Reg. 35442, 35567, 33572 (May 1, 2024); Update to
the Regulations Implementing NEPA Procedural Provisions, 85 Fed. Reg. 43304, 43365, 43372 (July 16, 2020); NEPA
Regulations: Implementation of Procedural Provisions, 43 Fed. Reg. 55978, 55997–98 (Nov. 29, 1978)). Following
recission of the CEQ guidance, some agencies provide for public comment on a draft EIS, while others do not.
147 See., e.g., Idaho Wool Growers Ass’n v. Vilsack, 816 F.3d 1095, 1102–04 (9th Cir. 2019) (describing NEPA’s
“expansive” consultation requirements).
148 For an example of a NEPA claim that included remand, vacatur, and an injunction, see CRS Legal Sidebar
LSB10943, The Willow Project: History and Litigation, by Adam Vann (2023).

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Declaratory Relief
Declaratory relief refers to the court’s formal determination of whether there was any violation of
the law.149 Permitting cases that are decided on the merits typically include a determination of
whether an agency violated the law. If no further remedy is ordered by the court, a prevailing
party would receive only declaratory relief. Declaratory relief alone is not a common remedy in
permitting actions, although the APA does expressly allow a claim for declaratory judgments.150

Remand
If a court determines an agency’s NEPA process requires reconsideration or a potential change, it
may order a lower court or agency to revisit a decision in order to cure a violation.151 For
example, remand may be ordered for an agency to consider certain information that was initially
excluded from its analysis, or to explain its reasoning for why it made a certain decision.152 A
court generally remands an issue to an agency where a judge decides an agency is best suited to
exercise its discretion on a NEPA matter and may order additional measures to bring that agency
into compliance with statutory obligations.153

Vacatur
When a court finds that an agency violated the APA, the statute directs the court to “set aside the
agency’s action,” which may result in vacatur.154 In NEPA cases, courts have recognized that
vacatur is the “ordinary” remedy.155 For example, a court may vacate a NEPA review or the
underlying action if an agency neglected to analyze a key impact or if the agency violated notice
and comment requirements or other procedural obligations that cast “serious doubt” over an
agency’s decision.156 Courts may vacate an agency’s environmental document or could potentially
149 See generally 28 U.S.C. § 2201(a) (“any court of the United States . . . may declare the rights and other legal

relations of any interested party seeking such declaration, whether or not further relief is or could be sought.”);
MedImmune, Inc. v. Genentech, Inc., 549 U.S. 118 (2007) (allowing the possibility of relief solely on declaratory
grounds, subject to judicial discretion); see also Kunkel v. Cont’l. Cas. Co., 866 F.2d 1269, 1274 (10th Cir. 1989)
(citing Aetna Life, 300 U.S. 227, 241 (1937) (“The declaration of rights, however, need not include injunctive or
monetary relief.”)).
150 5 U.S.C. § 703; see also 28 U.S.C. § 2201 (allowing for declaratory judgment “whether or not further relief is or
could be sought”).
151 See generally Fla. Power & Light Co. v. Lorion, 470 U.S. 729, 744 (1985) (“If the record before the agency does not
support the agency action, if the agency has not considered all relevant factors, or if the reviewing court simply cannot
evaluate the challenged agency action on the basis of the record before it, the proper course, except in rare
circumstances, is to remand to the agency for additional investigation or explanation.”). Additionally, an appellate court
may remand a matter to a lower court if there is additional action needed in order to proceed with a case.
152 See, e.g., Standing Rock Sioux Tribe v. U.S. Army Corps of Eng’rs, 282 F. Supp. 3d 91, 109 (D.D.C. 2017);
WildEarth Guardians v. Zinke, 368 F. Supp. 3d 41, 75 (D.D.C. 2019).
153 See, e.g., Mont. Wildlife Fed’n. v. Haaland, 127 F.4th 1, 52 (9th Cir. 2025).
154 5 U.S.C. § 706(2); see also Diné Citizens Against Ruining Our Env’t v. Haaland, 59 F.4th 1016, 1048 (10th Cir.
2023) (noting vacatur is a “common” and “appropriate” form of injunctive relief for a NEPA claim); Harmon v.
Thornburgh, 878 F.2d 484, 495 & n.21 (D.C. Cir. 1989) (“When a reviewing court determines that agency regulations
are unlawful, the ordinary result is that the rules are vacated—not that their application to the individual petitioners is
proscribed.”).
155 See Sierra Club v. U.S. Dep’t of Transp., 125 F.4th 1170, 1186 (D.C. Cir. 2025) (citing United Steel v. Mine Safety
& Health Admin., 925 F.3d 1279, 1287 (D.C. Cir. 2019)); Black Warrior Riverkeeper v. U.S. Army Corps of Eng’rs,
781 F.3d 1271, 1290 (11th Cir. 2015) (discussing history of remand without vacatur).
156 See, e.g., Vecinos para el Bienestar de la Comunidad Costera v. FERC, 6 F.4th 1321, 1332 (D.C. Cir. 2021)
(continued...)

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vacate the underlying decision that is the subject of the NEPA analysis.157 Courts may also vacate
a rule implementing NEPA promulgated by an agency.158
Notwithstanding the statutory requirement for a court to “set aside” agency action that violates
the APA, there are situations in NEPA cases where a court can remand a NEPA matter to an
agency without vacatur.159 Seven County Infrastructure Coalition clarified that a NEPA deficiency
may not be sufficient to warrant vacatur of an underlying project approval “absent reason to
believe that the agency might disapprove the project if it added more” to the NEPA analysis.160
Courts sometimes order remand without vacatur when finding “harmless error,” or if vacatur
would prove particularly disruptive.161 The D.C. Circuit and some other courts apply two primary
factors in considering vacatur: (1) the seriousness of the order’s deficiencies and (2) any
disruptive consequences of vacatur.162 For example, the D.C. Circuit has declined to vacate an
agency’s environmental review based on a conclusion that the agency was likely to remedy
deficiencies on remand, whereas vacating would have imperiled project funding.163 By contrast, a
court may be more likely to vacate if, for example, an agency’s actions on remand could change a
(declining to vacate FERC’s environmental review on the ground that the agency would likely remedy deficiencies on
remand, while vacating would imperil needed financing to ensure timely project completion); see generally Charles H.
Koch, Jr. & Richard Murphy, Types of Remedies in Review, 3 ADMINISTRATIVE LAW & PRACTICE § 8:31 (3d ed. 2020)
(describing the meaning of “set aside” under the APA) (citing, e.g., Nat. Res. Def. Council v. Wheeler, 955 F.3d 68, 85
(D.C. Cir. 2020); Standing Rock Sioux Tribe v. U.S. Army Corps of Eng’rs, 985 F.3d 1032 (D.C. Cir. 2021); Env’t
Def. Fund v. FERC, 2 F.4th 953, 976 (D.C. Cir. 2021)).
157 5 U.S.C. § 706(2) generally identifies the circumstances for courts to “set aside” an agency action.
158 See, e.g., Mila Sohoni, The Power to Vacate a Rule, 88 GEO. WASH. L. REV. 1121 (2020), https://www.gwlr.org/wpcontent/uploads/2020/09/88-Geo.-Wash.-L.-Rev.-1121.pdf [https://perma.cc/J68H-XYHJ]; Jameson M. Payne &
GianCarlo Canaparo, Is Vacatur Unconstitutional? (July 1, 2025) (draft manuscript),
https://papers.ssrn.com/sol3/papers.cfm?abstract_id=5333468 [https://perma.cc/E6QM-S8AT]. See also Harmon v.
Thornburgh, 878 F.2d 484, 495 & n.21 (D.C. Cir. 1989) (contemplating the possibility of vacating a rule under the
APA at a level that applies nationally).
159 Black Warrior Riverkeeper, 781 F.3d at 1290; STEPHANIE J. TATHAM, ADMIN. CONF. OF THE UNITED STATES, THE
UNUSUAL REMEDY OF REMAND WITHOUT VACATUR 30–36 (2014),
https://www.acus.gov/sites/default/files/documents/Remand%20Without%20Vacatur%20Final%20Report.pdf
[https://perma.cc/F6EL-4KAA] (finding a trend of remanding without vacatur in the D.C. Circuit, in particular with
respect to the Clean Air Act); cf. United States v. Texas, 599 U.S. 670, 686–703 (2023) (Gorsuch, J., concurring)
(discussing the meaning of “set aside” under the APA in the context of vacatur and other options for relief).
160 Seven Cnty. Infrastructure Coal. v. Eagle County, 145 S. Ct. 1497, 1514 (2025).
161 See, e.g., Ground Zero Ctr. for Non-Violent Action v. U.S. Dep’t of Navy, 860 F.3d 1244, 1252 (9th Cir. 2017)
(examining “whether the error materially impeded NEPA’s goals” such as by “precluding informed decisionmaking
and public participation” and not being “fully aware of the environmental consequences of the proposed action);
WildEarth Guardians v. U.S. Bureau of Land Mgmt., 870 F.3d 1222, 1240 (10th Cir. 2017) (remanding to lower court
to consider a narrower form of injunctive relief aside from vacatur); see generally Allied-Signal, Inc. v. Nuclear Reg.
Comm’n, 988 F.2d 146, 150–51 (D.C. Cir. 1993) (establishing factors for vacatur to include the seriousness of an
agency’s deficiencies and the “disruptive consequences” of potential ensuing changes); Diné Citizens Against Ruining
Our Env’t v. Haaland, 59 F.4th 1016, 1025 (10th Cir. 2023) (adopting the Allied-Signal approach).
162 Allied-Signal, 988 F.2d at 150–51. NEPA-specific opinions applying the Allied Signal test include Vecinos para el
Bienestar de la Comunidad Costera v. FERC, 6 F.4th 1321, 1332 (D. C. Cir. 2021), Mont. Wildlife Fed’n v. Haaland,
127 F.4th 1, 52 (9th Cir. 2025) (finding the disruptive consequences of lease vacatur significantly outweighed the
seriousness of the agency’s procedural error and further remanding to the agency for NEPA compliance while
enjoining (prohibiting) surface-disturbing activities “in the interim”), WildEarth Guardians v. U.S. Forest Serv., 137
F.4th 1068, 1092 (10th Cir. 2025) (directing trial court consideration of Allied Signal factors in consideration of the
remedy), Black Warrior Riverkeeper, 781 F.3d at 1290 (“In circumstances like these, where it is not at all clear that the
agency’s error incurably tainted the agency’s decisionmaking process, the remedy of remand without vacatur is surely
appropriate.”), and Ackerman Bros. Farms, LLC v. U.S. Dep’t of Agric., No. 1:17-CV-11779, 2021 WL 6133910, at *7
(E.D. Mich. Dec. 29, 2021) (finding the disruptive consequences of vacatur to outweigh the seriousness of the violation
that otherwise slightly weighed in favor of vacatur).
163 Vecinos para el Bienestar de la Comunidad Costera, 6 F.4th at 1332.

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project’s design based on a revised NEPA analysis or if the agency has a history of violating the
APA and NEPA.164

Injunctive Relief
A plaintiff may ask a court to impose injunctive relief in the form of requiring an agency to
undertake or refrain from undertaking a specific activity.165 When a court determines injunctive
relief is appropriate, that relief could be complete, in the sense of entirely halting an agency action
or project, or partial, such as by ordering that a project component proceed (or not) in a specific
manner without affecting the underlying action more broadly than the specific issue of concern.
The Supreme Court has stressed there is no “thumb on the scales” in favor of an injunction as
compared to ordering relief in the form of vacatur.166 A court could, for example, decline to vacate
an action and instead remand to correct a NEPA violation while ordering an interim injunction,
such as temporarily delaying project-level activity until the NEPA matter is cured.167
Sometimes in NEPA-related legal challenges, a plaintiff asks a court to impose a preliminary
injunction early in litigation before the matter can receive a full ruling on the merits or a
temporary restraining order to prevent imminent harm while the court considers whether to enter
a preliminary injunction.168 The Supreme Court has explained that a preliminary injunction is an
“extraordinary remedy” that is “never awarded as of right.”169 To obtain a preliminary injunction,
a plaintiff must show (1) a likelihood of success on the merits, (2) a likelihood of irreparable
harm in the absence of preliminary relief, (3) that the balance of the equities tips in the plaintiff’s
favor, and (4) that an injunction is in the public interest.170 While these four factors are generally
universal in application, courts vary in interpreting how they apply.171 For example, the Ninth
Circuit has explained that one way in which this four-part test could be met is where the plaintiff
has adequately raised “serious questions” on the merits, the balance of hardships sharply tilts in a
plaintiff’s favor, and the other two factors are also satisfied.172

164 See, e.g., Standing Rock Sioux Tribe v. U.S. Army Corps of Eng’rs, 985 F.3d 1032, 1050–53 (D.C. Cir. 2021).
165 See generally Types of Remedies in Review, 3 ADMINISTRATIVE LAW & PRACTICE § 8:31 (3d ed. 2024) (discussing

the scope of injunctive relief) (citing Sampson v. Murray, 415 U.S. 61, 78, 88 (1974)). Note that vacatur is sometimes
characterized as a specific form of injunctive relief. See, e.g., Diné Citizens, 59 F.4th at 1048.
166 Monsanto Co. v. Geertson Seed Farms, 561 U.S. 139, 157 (2010).
167 See, e.g., Mont. Wildlife Fed’n, 127 F.4th at 52 (reversing a lower court’s decision to vacate while temporarily
enjoining “surface-disturbing activity” until the agency complied with NEPA).
168 FED. R. CIV. P. 65. Temporary restraining orders typically expire within fourteen days or less and may be issued
without notice to the opposing party; preliminary injunctions typically last until judgment is rendered on the merits and
may be of longer duration than a temporary restraining order and typically require notice to the opposing party. Id.
169
Winter v. Nat. Res. Def. Council, Inc., 555 U.S. 7, 24 (2009).
170 Id. These four findings are sometimes referred to as the Winter factors. When a plaintiff seeks an injunction against
the government, the balance of equities and public interest factors merge. See Nken v. Holder, 556 U.S. 418, 435
(2009).
171 Compare Sierra Club, Inc. v. Bostick, 539 Fed. Appx. 885, 889 (10th Cir. 2013) (describing various opinions
interpreting Winter’s four factors, including several to support the proposition that failure to prove any one of the four
factors could result in a denial of a request for injunctive relief) with All. for the Wild Rockies v. Cottrell, 632 F.3d
1127, 1134 (9th Cir. 2011) (joining the Second and Seventh Circuits in adopting a “sliding scale” approach for
satisfying the four Winter factors).
172 See, e.g., Earth Island Inst. v. Muldoon, 82 F.4th 624, 640 (9th Cir. 2023) (denying a request for a preliminary
injunction in a NEPA where plaintiff’s failure to raise serious questions on the merits was dispositive and quoting Env’t
Prot. Info. Ctr. v. Carlson, 968 F.3d 985, 989 (9th Cir. 2020) (“Likelihood of success on the merits is a threshold
inquiry and is the most important factor.”)).

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A plaintiff seeking a permanent injunction must demonstrate (1) irreparable injury; (2) that
remedies available at law, such as monetary damages, are inadequate to compensate for that
injury; (3) that, considering the balance of hardships between the plaintiff and defendant, a
remedy in equity is warranted; and (4) that the public interest would not be disserved by a
permanent injunction.173 The burden is on a plaintiff to prove why the test is satisfied and the
injunction should be granted; such relief is not presumed.174 For example, the Supreme Court has
said that where a less “drastic” remedy, such as partial or complete vacatur of an underlying
action, is adequate to address a plaintiff’s injury, a court should not order additional extraordinary
relief in the form of an injunction.175 When a court orders an injunction in a NEPA case, it may be
lifted once the underlying violation is cured.176 In this context, even a “permanent” injunction for
a NEPA matter may be time limited, as the goal of any remedied NEPA analysis is to inform the
underlying agency decision on whether and how to proceed with a proposed action.

Considerations for Congress
Congress has numerous options to address judicial review of agency NEPA actions. While NEPA
itself has been amended a handful of times since its inception, Congress typically considers
hundreds of bills each congressional term with provisions addressing NEPA.177 Some of those
bills would affect how courts consider NEPA cases, while others would affect reviewability by
amending requirements in NEPA or individual agencies’ environmental review processes.
Introduced bills have offered changes to how courts would review an agency’s NEPA documents
in the context of a proposed action and to potential remedies a court may order if an agency’s
NEPA review has violated the law. Bills have also included approaches to clarify the scope of
environmental effects an agency considers in its decisionmaking.
Congress has considerable latitude to specify when and under what circumstances courts would
review an agency’s NEPA analysis. Congress could limit judicial review of NEPA claims by
restricting the scope of agency NEPA review or modifying the availability judicial review itself.
For example, some bills introduced in the 118th Congress, such as Senate Amendment 1911 to
H.R. 3935 or House Amendment 272 to H.R. 3935, would have limited consideration to effects
the agency has the authority to directly regulate (as opposed to effects of actions an agency has
the authority to take).178 Additionally, some Members have introduced bills that would affect the

173 Monsanto Co. v. Geertson Seed Farms, 561 U.S. 139, 156–57 (2010) (quoting eBay Inc. v. MercExchange L.L.C.,

547 U.S. 388, 391 (2006) and citing Winter, 555 U.S. at 31–33).
174 Id. at 158 (“It is not enough for a court considering a request for injunctive relief to ask whether there is a good
reason why an injunction should not issue; rather, a court must determine that an injunction should issue under the
traditional four-factor test set out above.”).
175 Id. at 165–66.
176 Where a court finds a NEPA violation and orders an underlying action vacated without additional injunctive relief,
the Supreme Court has clarified that plaintiffs concerned that an agency’s underlying action in response to vacatur
could subsequently violate NEPA would still have the right to bring a new legal challenge based on any ensuring
violations. Monsanto, 561 U.S. at 162. The practical distinction between this outcome and additional equitable relief in
the form of an injunction pending cure of a NEPA violation is not always clear, as both situations could result in a
temporary pause in an agency’s action in order to address the NEPA violation.
177 CONGRESS.GOV, “National Environmental Policy Act,” 1574 results (Aug. 27, 2025) (filtered by “Legislation”,
“1973–2026”), https://perma.cc/BDK7-ZHW9.
178 E.g., S.Amdt. 1911 to H.R. 3935, 118th Cong. (2024); H.Amdt. 272 to H.R. 3935, 118th Cong. (2024); see CRS In
Focus IF12417, Environmental Reviews and the 118th Congress, by Kristen Hite (2023).

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availability of judicial review of an agency’s NEPA analysis.179 Congress may also specify a more
or less deferential standard of review of the merits of an agency’s NEPA analysis.
Congress could also affect judicial review of NEPA analysis by amending the scope of which
agency actions are subject to NEPA and what agencies are required to consider when analyzing
environmental effects. Such changes could affect judicial review by expanding or contracting the
universe of actions for which NEPA analysis is required and therefore what a court could review.
Such amendments could also potentially affect NEPA litigation by imposing statutory guardrails
that courts would consider when evaluating whether an agency’s NEPA analysis was lawful.
Congress could consider enacting legislation in response to NEPA’s evolving regulatory
landscape.180 Recission of NEPA regulations and the Seven County opinion have shifted the onus
more squarely onto individual agencies to navigate NEPA implementation. Codifying some or all
of the elements of the NEPA process that were previously found only in CEQ regulations would
limit agency discretion in implementing NEPA and thus would somewhat limit the deference that
courts would otherwise afford to agencies. For example, incorporating specific procedural
requirements into statute would provide federal agencies, stakeholders, and courts with clarity on
the environmental review requirements Congress intends for agencies to apply. Alternatively, if
Congress believes NEPA is best implemented via a less standardized approach, Congress could
consider directing agencies to promulgate or update regulations detailing their NEPA procedures
based on any additional parameters that Congress believes to be warranted.

Author Information
Kristen Hite
Legislative Attorney

Disclaimer
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan
shared staff to congressional committees and Members of Congress. It operates solely at the behest of and
under the direction of Congress. Information in a CRS Report should not be relied upon for purposes other
than public understanding of information that has been provided by CRS to Members of Congress in
connection with CRS’s institutional role. CRS Reports, as a work of the United States Government, are not
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copy or otherwise use copyrighted material.

179 E.g., H.R. 471, § 121(c), 119th Cong. (2025); S. 4753, 118th Cong. (2024).
180 In 2025, after CEQ rescinded all government-wide regulations implementing NEPA, a number of agencies

subsequently rescinded all or part of their NEPA regulations. See, e.g., 90 Fed. Reg. 29393, 29393–29715 (July 3,
2025) (containing multiple agencies’ recissions or amendments to NEPA rules).

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/crs%3AR48717. Public record. Not legal advice.