CatEX vs EA vs EIS
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Description
The National Environmental Policy Act (NEPA) requires Federal agencies to evaluate the impacts of proposed Federal actions on the human environment. The NRC complies with NEPA through its regulations in 10 CFR Part 51. The regulations form the basis for the NRC's NEPA compliance and direct the staff in how to perform environmental reviews.
The Environmental Center of Expertise (ECOE) in the NRC's Office of Nuclear Material Safety and Safeguards conducts environmental reviews in support of NRC regulatory and licensing actions. The ECOE conducts NEPA reviews required for new licenses, license renewals, license amendments, and exemptions and for rulemakings. The ECOE also reviews and develops environmental guidance.

Categorical Exclusion (CatEX)
An NRC action may be "categorically excluded" from a detailed environmental review if the action does not "individually or cumulatively have a significant effect on the human environment" (10 CFR 51.14).
The NRC has determined that certain licensing, regulatory, and administrative actions are eligible for CatEX as specified at 10 CFR 51.22. For such actions, the NRC typically documents the CatEX in the safety evaluation related to the licensing action.

Environmental Assessment (EA) and the Finding of No Significant Impact (FONSI)
The NRC typically prepares an EA for actions that are not those identified as requiring an EIS per 10 CFR 51.20 and that do not meet the CatEX criteria at 10 CFR 51.22.
The EA, which must satisfy the requirements of 10 CFR 51.30, documents whether the action is a major Federal action that requires preparation of an environmental impact statement (EIS). If the NRC determines on the basis of the EA that the action will not have a significant impact on the environment, the NRC prepares a FONSI as specified at 10 CFR 51.32. Otherwise, if the NRC determines that the proposed action has the potential to significantly impact the environment, the NRC prepares an EIS.

Environmental Impact Statement (EIS) and the Record of Decision (ROD)
The NRC prepares an EIS for "major Federal actions significantly affecting the quality of the human environment" or for proposed actions that the Commission, as a matter of discretion, determines should be covered by an EIS. The NRC's regulations at 10 CFR 51.20 identify categories of actions requiring preparation of an EIS. For example, licensing the construction or operation of a nuclear power facility and the licensing of a uranium enrichment facility require an EIS. The EIS documents the potential environmental impacts of the action. The NRC also prepares a ROD when an EIS is prepared per the requirements of 10 CFR 51.102 and 51.103. The ROD documents the decision on the action and identifies the alternatives considered.
During an environmental review, the NRC staff analyzes the potential impacts of a proposed action on different aspects of the human environment, such as land use, visual resources, air quality, noise levels, aesthetics, geology and soils, surface and groundwater, terrestrial and aquatic ecology, human health, historic and cultural resources, socioeconomics, transportation, environmental justice, postulated accidents, decommissioning, and waste management. The staff also evaluates alternatives to the proposed action.
See the NRC web pages for material reviews, reactor license renewal, subsequent license renewal, and new reactors for more information about specific projects.
