771.115—Classes of actions.
There are three classes of actions which prescribe the level of documentation required in the NEPA process.
(a) Class I (EISs).
Actions that significantly affect the environment require an EIS ( 40 CFR 1508.27 ). The following are examples of actions that normally required an EIS:
(3)
New construction or extension of fixed rail transit facilities (e.g., rapid rail, light rail, commuter rail, automated guideway transit).
(4)
New construction or extension of a separate roadway for buses or high occupancy vehicles not located within an existing highway facility.
(b) Class II (CEs).
Actions that do not individually or cumulatively have a significant environmental effect are excluded from the requirement to prepare an EA or EIS. A specific list of CEs normally not requiring NEPA documentation is set forth in § 771.117(c). When appropriately documented, additional projects may also qualify as CEs pursuant to § 771.117(d).
(c) Class III (EAs).
Actions in which the significance of the environmental impact is not clearly estabilished. All actions that are not Class I or II are Class III. All actions in this class require the preparation of an EA to determine the appropriate environmental document required.