Updated October 22, 2020
The Legal Framework of the National Environmental Policy Act
The National Environmental Policy Act of 1969 (NEPA),
projects with minimal federal funding or involvement; and
42 U.S.C. §§ 4321 et seq., requires federal agencies to
(6) loans, loan guarantees, and other financial assistance
identify and evaluate impacts of “major Federal actions
where the federal agency does not exercise sufficient
significantly affecting the quality of the human
control or responsibility. Id. An agency may consider
environment.” Although an agency must consider these
whether other actions qualify as “major Federal actions.”
impacts, it need not elevate these environmental concerns
above others. Instead, NEPA requires agencies to “take a
NEPA Thresholds
hard look at environmental consequences” of their
The 2020 CEQ regulations include “thresholds” to codify
proposed actions, consider alternatives, and publicly
circumstances where courts have held that NEPA does not
disseminate such information before taking final action.
apply. 85 Fed. Reg. at 43,320. These thresholds require
Robertson v. Methow Valley Citizens Council, 490 U.S.
agencies to determine (1) whether the action is exempt by
332, 350 (1989) (emphasis added).
statute; (2) whether NEPA compliance would “clearly and
fundamentally conflict” with another statute; (3) whether
NEPA also established the Council on Environmental
NEPA compliance “would be inconsistent with
Quality (CEQ), which issues regulations and guidance
Congressional intent” of another statute; (4) whether the
detailing how federal agencies must implement NEPA. 40
action is nondiscretionary such that the agency lacks
C.F.R. pts. 1500–1518. Through these actions, CEQ has
authority to consider the environmental effects; and
defined and interpreted some of NEPA’s broad procedural
(5) whether review under a different statute is functionally
mandate. In 2020, CEQ finalized revisions to its 1978
equivalent to NEPA. 40 C.F.R. § 1501.1(a). Agencies may
NEPA regulations, which apply to all proposals subject to
codify these thresholds into their own NEPA regulations.
NEPA reviews after September 14, 2020, although agencies
Id. §§ 1501.1(b), 1507.3(d)(6). They may also consult with
may choose to apply them to ongoing reviews. 85 Fed. Reg.
CEQ in determining whether one of these considerations
43,304 (July 16, 2020). These regulations are being
applies to a particular case. Id. § 1501.1(b)(1).
challenged by a number of states and other stakeholders,
but will remain in effect unless the courts grant temporary
Assessing Significant Impacts
or permanent legal remedies to pause implementation until
Before undertaking NEPA review for “major Federal
the litigation is resolved.
actions,” the 2020 CEQ regulations require an agency to
This In Focus describes the legal obligations that NEPA
assess whether the proposed action (1) normally has no
and the 2020 CEQ regulations impose on federal agencies.
significant impacts and is categorically excluded, (2) is
It also highlights some changes that the 2020 CEQ
likely to have insignificant impacts or unknown impacts, or
regulations made to the 1978 regulations.
(3) is likely to have significant impacts. Id. § 1501.3.
Federal Actions Subject to NEPA
CEQ directs agencies to determine whether the impacts
from a proposed action are “significant” by assessing the
Generally, NEPA’s procedural mandates apply to all
“potentially affected environment and degree of the effects”
proposed “major Federal actions significantly affecting the
the action may have. Id. § 1501.3(b). These effects must
quality of the human environment.” 42 U.S.C. § 4332.
include “short- and long-term effects”; “beneficial and
Accordingly, to determine if NEPA applies to a proposed
adverse effects”; “effects on public health and safety”; and
activity, agencies must assess whether the action is “major,”
effects that would violate laws protecting the environment.
if the effects from the major action are “significant,” and
Id. “Effects” are defined in the 2020 CEQ regulations as
whether the action is otherwise exempt from NEPA.
“changes to the human environment from the proposed
Definition of “Major Federal Action”
action or alternatives that are reasonably foreseeable and
have a reasonably close causal relationship to” those
NEPA does not define “major Federal action.” CEQ,
actions. This includes effects “that occur in the same time
however, has developed a definition, limiting the scope
and place” as the proposed and alternative actions, as well
to actions “subject to Federal control and responsibility.”
as effects that are “later in time or farther removed.”
40 C.F.R. § 1508.1(q). The 2020 CEQ regulations further
However, a “‘but for’ causal relationship is insufficient to
refine the scope by listing actions that do not qualify
make an agency responsible for a particular effect under
and other actions that may or “tend to” qualify. Actions
NEPA.” Id.
that do not qualify as major federal actions include
(1) nondiscretionary or extraterritorial activities or
The current definition of “effects” builds on but also
decisions; (2) actions that do not result in final agency
departs from the 1978 regulations in several ways. First,
actions as set forth in statute; (3) judicial or administrative
CEQ revised the definition of “effects” by eliminating
enforcement; (4) certain funding assistance where a federal
references to “direct” and “indirect” effects, which are not
agency does not control the funds’ use; (5) nonfederal
terms used in NEPA. Second, the definition seeks to clarify
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The Legal Framew ork of the National Environmental Policy Act
that agencies need not analyze effects of their proposed
Once an agency reaches a final decision on the action it
actions that are beyond their control. Third, CEQ eliminated
wishes to take (i.e., the proposed action or an alternative), it
the requirement that agencies consider the cumulative
creates a record of it in a written statement called a Record
impacts from the proposed activity and related actions.
of Decision (ROD). Id. § 1505.2. The ROD is issued at
Finally, the 2020 CEQ regulations require an “agency’s
least 90 days after publishing a draft EIS or 30 days after
analysis of effects to be consistent” with the regulations’
issuing a final EIS. The 2020 regulations require the ROD
revised definition of “effects,” which appears to limit the
to contain a statement certifying that the agency considered
effects that an agency may consider. Id. § 1508.1(g)(3).
all alternatives, information, and analyses submitted during
the NEPA process. Id. A certified EIS is “entitled to a
By eliminating references to “direct,” “indirect,” and
“
presumption that the agency considered the submitted
cumulative” impacts, CEQ’s revised definition of “effects”
alternatives, information, and analysis . . . in its decision.”
could alter how agencies consider the climate change
Id.
effects of their proposed actions. Various courts have held
that an agency’s NEPA review should consider the
Environmental Assessments: Unknown Impacts
“reasonably foreseeable” direct, indirect, and cumulative
For actions that may have some impacts —but potentially
effects from the proposed action’s greenhouse gas
not significant impacts—agencies must prepare an
emissions. In the 2020 rulemaking, however, CEQ stated
that agencies may characterize “[t]rends
environmental assessment (EA). An EA is an initial
determined to be a
analysis of an action’s potential to have significant
consequence of climate change . . . in the baseline analysis
environmental effects. While preparing an EA, an agency
of the affected environment rather than as an effect of the
action.” 85 Fed. Reg. at 43
must consult with other federal and state agencies with
,331.
jurisdiction over a proposal’s impacts. Agencies also
Environmental Impact Statements:
involve the public in preparing EAs “to the extent
practicable.”
Significant Impacts
Id. § 1501.5(e). An EA may lead to a decision
to complete an EIS or to a finding of no significant impact
For actions with significant impacts, NEPA requires federal
(FONSI). The 2020 regulations set presumptive page and
agencies to prepare, “to the fullest extent possible,” a
“detailed statement” known as an environmental impact
time limits for EAs: 75 pages, excluding appendixes, within
one year. Id. §§ 1501.5, 1501.10.
statement (EIS). 42 U.S.C. § 4332. In its EIS, an agency
must assess (1) the environmental impacts of the proposal;
Categorical Exclusions: No Significant Impacts
(2) unavoidable adverse environmental effects;
Under the 1978 regulations, CEQ allowed an agency to
(3) alternatives to the proposed action; (4) the relationship
issue regulations identifying “categorical exclusions” (CEs)
between the short-term uses of the environment and
—actions that do not individually or cumulatively have
maintenance of long-term productivity; and (5) any
significant effects on the human environment. These CEs
irretrievable resource commitments involved if the proposal
may be excluded from further NEPA analysis unless an
is implemented. Id. To determine the EIS’s scope, an
agency identifies extraordinary circumstances for a specific
agency must consider (1) connected or similar actions;
project that indicate the proposed action may have
(2) “a reasonable number” of alternatives to the proposed
significant impacts. Id. § 1501.4. The 2020 CEQ
action (no action, other “reasonable” actions, and mitigation
regulations extend agencies’ ability to address projects
measures); and (3) effects. 40 C.F.R. §§ 1501.9(e), 1502.14.
without significant impacts. Specifically, these regulations
An agency must release its draft EIS for comment from
permit an agency to adopt another agency’s CE
other agencies and the public. 42 U.S.C. § 4332(2)(C).
determination if the proposed action is “substantially the
Under the 2020 regulations, public comments not submitted
same” as the action that the other agency already
during the comment period are deemed forfeited and
determined was categorically excluded from NEPA. Id.
unexhausted and cannot be raised later in court. 40 C.F.R.
§ 1506.3(d).
§ 1503.3(b).
A final EIS must respond to comments from agencies and
Judicial Review of NEPA Compliance
the public by modifying the proposal, developing
NEPA does not expressly provide for judicial review. Thus,
alternatives, or explaining why comments do not merit
legal challenges to an agency’s NEPA compliance are
substantive replies or changes. Id. §§ 1503.4. The 2020
subject to federal judicial review under the Administrative
regulations also stipulate that a final EIS should be
Procedure Act. 5 U.S.C. §§ 551 et seq. When reviewing an
“proportional to potential environmental effects and project
agency’s final action, the court’s role is “to ensure that the
size,” but no more than 150 pages, or 300 pages if
agency has adequately considered and disclosed the
unusually complex. Id. §§ 1502.2(c), 1502.7. Further, an
environmental impact of its actions and that its decision is
EIS should be completed within two years unless the lead
not arbitrary or capricious.” Balt. Gas & Elec. Co. v.
agency approves a longer time. Id. § 1502.10(b)(2). In some
NRDC, 462 U.S. 87, 97–98 (1983). The 2020 CEQ
circumstances, an agency may also need to create a
regulations address the types of agency actions that may be
supplemental EIS after preparing (and issuing for public
subject to judicial review and CEQ’s intended remedies for
comment) a draft or final EIS if the agency makes
NEPA noncompliance. 40 C.F.R. § 1500.3.
“substantial changes” to its initial proposal or learns of
“significant new circumstances or information” related to
Nina M. Hart, Legislative Attorney
environmental concerns. Id. § 1502.9(d).
Linda Tsang, Legislative Attorney
IF11549
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The Legal Framew ork of the National Environmental Policy Act


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