The Environmental Protection Agency (EPA) is approving a State Implementation Plan (SIP) revision submitted by the State of New Hampshire. This revision includes an amended regulation for the Enhanced Motor Vehicle Inspection and Maintenance (I/M) program in New Hampshire. Overall, the submittal updates and clarifies the implementation of the New Hampshire I/M program. The intended effect of this action is to approve the updated I/M program regulation into the New Hampshire SIP. This action is being taken in accordance with the Clean Air Act.