An air operating permit compiles all of the operating conditions and applicable requirements for a source in a single document. Operating approvals that are issued for new or expanding facilities are usually combined with the appropriate level of new source review. Indiana’s operating permit programs include:
- Part 70 Operating Permit (also referred to as a Title V permit): incorporates the requirements of Title V of the federal Clean Air Act and U.S. EPA rules found at 40 CFR Part 70 for sources with a potential to emit (PTE) above Title V major source thresholds.
- See 326 IAC 2 [PDF], Rule 7.
- Federally Enforceable State Operating Permit (FESOP): for eligible facilities that would otherwise be subject to the Part 70 program based on PTE but agree to limit PTE below the Title V major source thresholds. A FESOP is referred to as a synthetic minor permit, since it contains limitations on PTE to be a minor source.
- See 326 IAC 2 [PDF], Rule 8.
- Minor Source Operating Permit (MSOP): primarily for sources with PTE between registration and Part 70 thresholds that are not otherwise subject to Part 70 requirements based on industry category. MSOP is referred to as a natural minor permit, since it does not require any limitations to be a minor source.
- See 326 IAC 2 [PDF], Rule 6.1.
Indiana also has several alternate approval programs that may be appropriate for certain sources.