CE (Categorical Exclusion)
A CE is based on an agency's experience with a particular kind of action and its environmental effects. The agency may have studied the action in previous EAs, found no significant impact on the environment based on the analyses, and validated the lack of significant impacts after the implementation. If this is the type of action that will be repeated over time, the agency may decide to amend their implementing regulations to include the action as a CE. In these cases, the draft agency procedures are published in the Federal Register, and a public comment period is required. Participation in these comment periods is an important way to be involved in the development of a particular CE. A CE for one agency cannot be used by a different agency unless that agency has followed this procedure.
Read more about this topic: National Environmental Policy Act