---
kind: "section"
citation: "42 U.S.C. § 4336"
title: "42"
title_heading: "The Public Health and Welfare"
number: "4336"
heading: "Procedure for determination of level of review"
release: "119-102"
date: "2026-07-12"
url: "https://uscodex.org/usc/42/4336"
units:
  - "Chapter 55 — National Environmental Policy"
  - "Subchapter I — Policies and Goals"
---

# §4336. Procedure for determination of level of review

- (a) **Threshold determinations—** An [agency](/usc/42/8262.md?p=1) is not required to prepare an [environmental document](/usc/42/4336e.md?p=5) with respect to a proposed [agency](/usc/42/8262.md?p=1) action if—
  - (1) the proposed [agency](/usc/42/8262.md?p=1) action is not a final [agency](/usc/42/8262.md?p=1) action within the meaning of such term in [chapter 5](/usc/5/chptI/ch5.md) of title 5;
  - (2) the proposed [agency](/usc/42/8262.md?p=1) action is excluded pursuant to one of the [agency](/usc/42/8262.md?p=1)’s [categorical exclusions](/usc/42/4336e.md?p=1), another [agency](/usc/42/8262.md?p=1)’s [categorical exclusions](/usc/42/4336e.md?p=1) consistent with [section 4336c of this title](/usc/42/4336c.md), or another provision of law;
  - (3) the preparation of such document would clearly and fundamentally conflict with the requirements of another provision of law; or
  - (4) the proposed [agency](/usc/42/8262.md?p=1) action is a nondiscretionary action with respect to which such [agency](/usc/42/8262.md?p=1) does not have authority to take environmental factors into consideration in determining whether to take the proposed action.
- (b) **Levels of review—**
  - (1) **Environmental impact statement—** An [agency](/usc/42/8262.md?p=1) shall issue an [environmental impact statement](/usc/42/4336e.md?p=6) with respect to a proposed [agency](/usc/42/8262.md?p=1) action requiring an [environmental document](/usc/42/4336e.md?p=5) that has a reasonably foreseeable significant effect on the quality of the human environment.
  - (2) **Environmental assessment—** An [agency](/usc/42/8262.md?p=1) shall prepare an [environmental assessment](/usc/42/4336e.md?p=4) with respect to a proposed [agency](/usc/42/8262.md?p=1) action that does not have a reasonably foreseeable significant effect on the quality of the human environment, or if the significance of such effect is unknown, unless the [agency](/usc/42/8262.md?p=1) finds that the proposed [agency](/usc/42/8262.md?p=1) action is excluded pursuant to one of the [agency](/usc/42/8262.md?p=1)’s [categorical exclusions](/usc/42/4336e.md?p=1), another [agency](/usc/42/8262.md?p=1)’s [categorical exclusions](/usc/42/4336e.md?p=1) consistent with [section 4336c of this title](/usc/42/4336c.md), or another provision of law. Such [environmental assessment](/usc/42/4336e.md?p=4) shall be a concise public document prepared by a Federal [agency](/usc/42/8262.md?p=1) to set forth the basis of such [agency](/usc/42/8262.md?p=1)’s [finding of no significant impact](/usc/42/4336e.md?p=7) or determination that an [environmental impact statement](/usc/42/4336e.md?p=6) is necessary.
  - (3) **Sources of information—** In making a determination under this subsection, an [agency](/usc/42/8262.md?p=1)—
    - (A) may make use of any reliable data source; and
    - (B) is not required to undertake new scientific or technical research unless the new scientific or technical research is essential to a reasoned choice among alternatives, and the overall costs and time frame of obtaining it are not unreasonable.

## Source credit

(Pub. L. 91–190, title I, § 106, as added Pub. L. 118–5, div. C, title III, § 321(b), June 3, 2023, 137 Stat. 39.)