NEPA Process

What is the National Environmental Policy Act?

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The NEPA Process

The National Environmental Policy Act (NEPA) (42 United States Code § 4321 et seq.), as amended by the Fiscal Responsibility Act of 2023 (Public Law 118-5), requires federal agencies to evaluate the environmental effects of proposed major federal actions before decisions are made regarding whether and how to proceed. The Department of the Air Force (DAF) prepares NEPA documentation in accordance with applicable federal requirements, including the 2026 Department of War and 2026 DAF NEPA Implementing Procedures.

Public Scoping Period

Scoping is a component of the NEPA process during which the lead agency solicits input from federal, state, Tribal, and local agencies; interested organizations; and the public regarding potentially affected resources, environmental issues to be considered, and the agency’s proposed approach for analyzing the effects of the proposed action.

The scoping period begins with publication of the Notice of Intent (NOI) in the Federal Register. The NOI explains how interested individuals and organizations can participate in the scoping process by reviewing project information and submitting comments. Although public input is accepted at any time during the NEPA process, the public is encouraged to submit comments within 30 days of publication of the NOI so the DAF and the Cooperating Agencies can fully consider the comments received during preparation of the Draft Environmental Impact Statement (EIS).

This scoping period is for the Supplemental Environmental Impact Statement (SEIS), which will evaluate how updates to Sentinel deployment plans since issuance of the 2023 EIS and signing of the associated Record of Decision (ROD) may affect a broad range of environmental, cultural, socioeconomic, and community resources.

Rendering of Sentinel.

Photo Credit: Northrop Grumman.

Draft SEIS Comment Period

When an agency prepares a Draft SEIS and publishes it, the public is provided an opportunity to review and comment on the document during a designated comment period. The review period begins with publication of the Notice of Availability (NOA) by the U.S. Environmental Protection Agency in the Federal Register. Concurrently, notices are published in local newspapers and on agency websites. The NOA and related notices invite the public to review the Draft SEIS and submit comments on the analysis and findings during the comment period. All comments received are carefully considered, and substantive comments are addressed, as appropriate, during preparation of the Final SEIS.

Final SEIS and ROD

The DAF will prepare a Final SEIS that considers comments received during the Draft SEIS comment period. The NEPA process concludes with issuance of the ROD, which documents the agency’s decision and describes required mitigation measures. NOAs for the Final SEIS and ROD will be published in the Federal Register, and the DAF will make both documents available on a publicly accessible website.