The Environmental Protection Agency (EPA) is approving a State Implementation Plan (SIP) revision submitted by the State of New Hampshire that contains an ozone maintenance plan for New Hampshire's former 1-hour ozone nonattainment areas. The Clean Air Act requires that areas that are designated attainment for the 1997 8-hour ozone standard, and also had been previously designated either nonattainment or maintenance for the 1-hour ozone standard, develop a plan showing how the state will maintain the ozone standard for the area. The intended effect of this action is to approve New Hampshire's maintenance plan. This action is being taken in accordance with the Clean Air Act.