Designation of Areas for Air Quality Planning Purposes; Montana; Redesignation Request and Associated Maintenance Plan for East Helena SO2 Nonattainment Area

Résumé

The Environmental Protection Agency (EPA) is approving the State of Montana's request to redesignate the East Helena sulfur dioxide (SO 2 ) nonattainment area to attainment for the 1971 primary and secondary SO 2 National Ambient Air Quality Standards (NAAQS). The EPA is also approving Montana's maintenance plan which provides for continued attainment of the 1971 primary and secondary SO 2 NAAQS in the East Helena area. The EPA is taking these actions pursuant to section 110 of the Clean Air Act (CAA). This final rulemaking action includes the EPA's determination that the East Helena SO 2 nonattainment area attains the 1971 primary and secondary SO 2 NAAQS. The emissions offset and highway funding sanctions were imposed on the State of Montana for the East Helena SO 2 nonattainment area because the State did not submit a required attainment demonstration for the 1971 secondary SO 2 NAAQS. Because the area is being redesignated for this standard and is no longer obligated to submit an attainment demonstration, the sanctions will no longer apply as of the effective date of this final rule.