A CX is a “category of actions that a Federal agency has determined normally does not significantly affect the quality of the human environment” (NEPA Section 111). Those classes of actions are listed in DOE NEPA Implementing Procedures Appendices B and C.
Under the DOE NEPA Implementing Procedures Section 2.1, if DOE has determined that NEPA applies to a proposed action, DOE will then determine if applying a CX to the proposed action is appropriate. DOE will review the NEPA Implementing Procedures Appendices B and C to make a CX determination. If no existing relevant CX exists in either Appendices, DOE may consider revising or adopting an existing CX or establishing a new CX.
See the Office of Environmental Management’s CX determinations.