National Environmental Policy Act (NEPA)

Welcome to the U.S. Department of Energy National Nuclear Security Administration (NNSA) Service Center’s ( SC ) National Environmental Policy Act (NEPA) Website. The SC NEPA Website serves as a focal point for the Service Center’s posting of NEPA documents related to Service Center operations as described below.

The National Environmental Policy Act (NEPA) requires federal agencies to consider the environmental consequences of proposed actions before decisions are made and to share these with the public. (dual purpose) In complying with NEPA, the NNSA Service Center follows the Council on Environmental Quality (CEQ) regulations (40 CFR 1500-1508) and the Department of Energy’s (DOE) implementing regulations (10 CFR 1021). There are three types of NEPA documents, an Environmental Impact Statement (EIS), an Environmental Assessment (EA), and a Categorical Exclusion (CX) determination. Below are definitions/explanations of some of these documents.


Environmental Impact Statements (EIS)

The detailed written statement that is required by section 102(2)(C) of the National Environmental Policy Act for a proposed major Federal action significantly affecting the quality of the human environment.

Environmental Assessment (EA)

A concise public document that a Federal agency prepares under the National Environmental Policy Act to provide sufficient evidence and analysis to determine whether a proposed agency action would require preparation of an environmental impact statement or a finding of no significant impact.

Categorical Exclusions (CX)

Categorical exclusions are categories of actions that DOE has determined do not individually or cumulatively have a significant effect on the human environment, and for which, therefore, neither an environmental assessment nor an environmental impact statement normally is required. DOE's categorical exclusions are listed in Appendices A and B to Subpart D of its NEPA regulations, codified at 10 CFR Part 1021 (39 KB, doc).


EISs and EAs have traditionally been posted on agency web sites to inform the public and to ask for their review of a particular document. EAs and EISs prepared for the NNSA will be posted on the NNSA NEPA Reading Room page, link found in the right column of this page. Comments can be made on a draft document by going to this reading room and clicking on a document. There you will find review instructions.  Also, on the reading room page under Notices, you will find document availability information.  Additionally, EAs and EISs will be made available to the public in hard copy at local public reading rooms or mailed to individuals upon request.

To further transparency and openness in its implementation of the NEPA process, DOE has established a policy to document and post online its categorical exclusion (CX) determinations involving classes of actions listed in Appendix B to Subpart D of the Department’s NEPA regulations, 10 CFR Part 1021. CX determinations will be posted on the NNSA NEPA Reading Room web page or the NNSA Site web page.