May 14, 2020
The Legal Framework of the National Environmental Policy Act
The National Environmental Policy Act of 1969 (NEPA),
Environmental Impact Statements: Significant
42 U.S.C. § 4321 et seq., declared a national policy “to
Impacts
create and maintain conditions under which man and nature
For actions with significant impacts, an agency must
can exist in productive harmony, and fulfill the social,
prepare, “to the fullest extent practicable,” a “detailed
economic, and other requirements of present and future
statement” known as an environmental impact statement
generations of Americans.” To implement this policy,
(EIS). 42 U.S.C. § 4332. In its EIS, the agency must
NEPA requires federal agencies to identify and evaluate
address (1) the environmental impacts of the proposal;
impacts of “major Federal actions significantly affecting the
(2) unavoidable adverse environmental effects;
quality of the human environment.” 42 U.S.C.
(3) alternatives to the proposed action; (4) the relationship
§ 4332(2)(C). Although an agency must consider these
between the short-term uses of the environment and
impacts, it need not elevate these environmental concerns
maintenance of long-term productivity; and (5) any
above others. Instead, NEPA requires agencies to “take a
irretrievable resource commitments involved if the proposal
hard look at environmental consequences” of their
is implemented. 42 U.S.C. § 4332(2)(C). To determine the
proposed actions, consider alternatives, and publicly
EIS’s scope, the CEQ regulations require an agency to
disseminate such information before taking final action.
consider (1) connected, cumulative, or similar actions;
Robertson v. Methow Valley Citizens Council, 490 U.S.
(2) three types of alternatives (no action, other “reasonable”
332, 350 (1989) (emphasis added).
actions, and mitigation measures); and (3) direct, indirect,
or cumulative impacts. 40 C.F.R. § 1508.25.
NEPA also established the Council on Environmental
Quality (CEQ), which issues regulations and guidance
An agency must release its draft EIS for comment from
detailing how federal agencies must implement NEPA. 40
other agencies and the public. 40 C.F.R. § 1503.1. The final
C.F.R. pts. 1500–18. Each federal agency must also
EIS must consider comments by modifying the proposal,
develop its own regulations, which must be consistent with
developing alternatives, or explaining why comments do
the CEQ regulations. Id. § 1507.3. In January 2020, CEQ
not merit substantive replies or changes.
proposed a revision of its regulations.
In some circumstances, an agency may also need to create a
This In Focus describes the legal obligations that NEPA
supplemental EIS (SEIS) after preparing a draft or final EIS
and the CEQ regulations impose on federal agencies,
if the agency makes “substantial changes” to its initial
highlights proposed changes to the regulations, and
proposal or learns of “significant new circumstances or
discusses how climate change effects are considered in
information” related to environmental concerns. 40 C.F.R.
NEPA reviews.
§ 1502.9. As with other NEPA documents, the agency must
make the SEIS available for public comment.
Federal Actions Subject to NEPA
Generally, NEPA’s procedural mandates apply to all
At the end of the NEPA process, an agency creates a record
proposed “major Federal actions significantly affecting the
of its final decision (i.e., to proceed with the proposed
quality of the human environment.” 42 U.S.C. § 4332.
action or with an alternative action). 40 C.F.R. § 1505.2.
NEPA does not define “major Federal action,” except to
The agency must memorialize its decision in a written
limit the phrase to actions “subject to Federal control and
statement called a Record of Decision (ROD), which is
responsibility.” Id. The CEQ regulations clarify that such
issued at least 90 days after publishing a draft EIS or 30
actions qualify as “major” only if they significantly impact
days after issuing a final EIS.
the environment. 40 C.F.R. § 1508.18. In determining
whether an action is significant, an agency must look at the
Environmental Assessments: Uncertain Impacts
“context” (societal, affected region and interests, and
For actions that may have some level of impact, but
locality) and “intensity” (severity of impact) of its proposed
potentially not significant impacts, agencies must prepare
action. Id. § 1508.27.
an environmental assessment (EA) according to their
agency-specific regulations. 40 C.F.R. § 1501.3. An EA is
The CEQ regulations also identify three classes of federal
an initial analysis of an action’s potential to have significant
action based on an agency’s prior experience with similar
environmental effects. While preparing an EA, an agency
actions. The next sections discuss how an agency must
must consult with other agencies that may be affected or
proceed under NEPA based on whether the proposed action
have jurisdiction over part of the proposed action and with
has (1) significant impacts, (2) uncertain impacts, or (3) no
the public “to the extent practicable.” An EA may lead to a
significant impacts.
decision to complete a more detailed analysis (i.e., an EIS)
or to a finding of no significant impact (FONSI).
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The Legal Framework of the National Environmental Policy Act
Categorical Exclusions: No Significant Impacts
eliminating separate definitions for direct, indirect, and
As part of its NEPA regulations, an agency may identify
cumulative effects. The proposed definition includes,
“categorical exclusions” (CEs)—categories of actions that
among other things, language from Department of
do not individually or cumulatively have significant effects
Transportation v. Public Citizen, 541 U.S. 752 (2004),
on the human environment. The agency may exclude CEs
stating that “‘but for’ causation is insufficient to make an
from further analysis in an EA or EIS. 40 C.F.R.
agency responsible for a particular effect under NEPA.”
§§ 1507.3(b), 1508.4. The CEQ regulations, however, also
This language seeks to clarify that agencies need not
create procedures to address “extraordinary circumstances”
analyze effects of their proposed actions that are beyond the
when actions that usually qualify as CEs may have
agency’s control.
significant environmental impacts and thus require further
NEPA review.
CEQ’s proposed regulations also aim to facilitate
“efficient” or “timely” reviews by inserting several
Limits to NEPA’s Applicability
provisions that may affect NEPA litigation. First, relying on
When an agency performs a NEPA review, certain actions
federal case law, the new regulations could limit an
or effects may fall outside the statute’s scope. For instance,
individual’s ability to challenge an agency’s NEPA
Congress has expressly exempted certain actions from
compliance in federal court if that individual failed to
NEPA review. For example, Congress declared that “[n]o
submit a comment during the public comment period on the
action taken under the Clean Air Act shall be deemed a
issue raised in court. Second, the proposal would amend the
major federal action significantly affecting the quality of
actions that qualify as “final agency action.” Generally,
the human environment within the meaning of the National
judicial review of an agency’s NEPA compliance may
Environmental Policy Act.” 15 U.S.C. § 793(c)(1).
occur only after final agency action. The proposal replaces
references to filing an EIS or FONSI as “final agency
Additionally, courts have recognized some limits to the
action” with language stating that CEQ “intend[s] that
scope of what an agency must include in its NEPA
judicial review ... not occur before an agency has issued the
evaluation. For instance, when an agency lacks discretion or
[ROD] or taken other final agency action.”
control over certain aspects of a proposed action, it need not
address the environmental effects of these aspects. As the
CEQ’s proposal includes other revisions, such as clarifying
Supreme Court held in Department of Transportation v.
an agency’s use of CEs and FONSIs; modifying
Public Citizen, 541 U.S. 752 (2004), because an agency
coordinating procedures for states, Tribes, and local
lacked authority to control the cross-border operations of
governments; changing the public comment process; and
Mexican trucks, it was not required to analyze the
“improving the format and readability of the regulations.”
environmental impacts of such operations.
CEQ closed the comment period on March 10, 2020.
Judicial Review of NEPA Compliance
NEPA and Climate Change
NEPA does not expressly provide for judicial review. Thus,
Various court decisions, executive orders, and CEQ
legal challenges to an agency’s NEPA compliance,
guidance have addressed how climate change factors into
including FONSIs and RODs, are subject to federal judicial
NEPA reviews. For example, in 2016, CEQ issued
review under the Administrative Procedure Act. 5 U.S.C.
guidance clarifying how all federal agencies should
§§ 701–06, 551 et seq.; 40 C.F.R. § 1508.18. When
consider potential greenhouse gas (GHG) emissions in
reviewing an agency’s final action, the court’s role is “to
NEPA reviews. In 2017, President Trump rescinded this
ensure that the agency has adequately considered and
guidance in Executive Order 13783.
disclosed the environmental impact of its actions and that
its decision is not arbitrary or capricious.” Balt. Gas & Elec.
In addition to these executive actions, federal courts have
Co. v. NRDC, 462 U.S. 87, 97–98 (1983). According to
addressed how federal agencies consider GHG emissions
CEQ, the Supreme Court has directly addressed NEPA in
when reviewing the direct, indirect, and cumulative effects
17 opinions, and federal courts have issued approximately
of proposed actions. Various courts have held that an
100 to 140 opinions annually interpreting and enforcing
agency’s NEPA review should consider the “reasonably
NEPA obligations.
foreseeable” direct and indirect effects from the proposed
action’s GHG emissions. However, courts have taken
Proposed Changes to NEPA Regulations
varying approaches regarding an agency’s review of the
CEQ’s NEPA regulations have been largely unchanged
proposed project’s upstream and downstream GHG
since they were promulgated in 1978. In January 2020,
emissions. CEQ’s proposed regulatory changes, which
CEQ proposed revisions intended to “modernize and clarify
might not require agencies to consider indirect or
the CEQ regulations to facilitate more efficient, effective,
cumulative effects in their NEPA review, could affect how
and timely NEPA reviews.” 85 Fed. Reg. 1684 (Jan. 10,
agencies consider the climate change effects of their
2020). To achieve this objective, CEQ proposes to replace
proposed actions.
the existing NEPA regulations in their entirety and
supersede all of its previous NEPA guidance.
Nina M. Hart, Legislative Attorney
Linda Tsang, Legislative Attorney
CEQ proposes to “codify” in the new regulations certain
executive guidance or directives and case law about NEPA
IF11549
to “reflect current” practice. For example, the regulations
propose to adopt a single definition of “effects or impacts,”
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The Legal Framework of the National Environmental Policy Act


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