Following are Requests for Redesignation and Maintenance Plans Indiana has submitted to United States Environmental Protection Agency (U.S. EPA) for Huntington County, Indiana, listed by applicable National Ambient Air Quality Standard (NAAQS).
Sulfur Dioxide (SO2)
2010 Primary 1-Hour SO2 Standard
Huntington Township in Huntington County makes up the Huntington, IN Nonattainment Area designated by U.S. EPA under the 2010 Primary 1-Hour SO2 Standard.
- Federal Register Notice Concerning U.S. EPA Approval of the Maintenance Plan for the Huntington, Indiana (IN) 2010 Primary 1-Hour Sulfur Dioxide (SO2) Nonattainment Area (January 9, 2026) [PDF]
- Technical Clarification for the Huntington, Indiana (IN) 2010 Primary 1-Hour Sulfur Dioxide (SO2) Nonattainment Area (September 17, 2024) [PDF]
- Request for Redesignation and Maintenance Plan for the Huntington, Indiana (IN) 2010 Primary 1-Hour Sulfur Dioxide (SO2) Nonattainment Area (July 30, 2024) [PDF]