On March 24, 2017, the Illinois Pollution Control Board (IPCB) finalized the rules to allow construction of small boilers under a "permit by rule." The permit by rule eliminates the need to individually grant construction permits for the covered boilers. Additionally, general provisions for permits by rule were finalized, which will apply to future proposed permits by rule for other types of emission units.

Under the general provision, an applicant may obtain a permit by rule for a new or modified emission unit if the unit is located at an existing source authorized to operate under the Clean Air Act Permit Program (CAAPP), a permit by rule has been adopted by the board for the specified emission unit (e.g., small boiler), the emission unit is not an element in a larger project that otherwise requires a construction permit, and the emission unit does not otherwise trigger permitting requirements.

The eligible types of boilers for the permit by rule include:

  • Boilers with a maximum design heat input capacity less than or equal to 50 MMBtu/hr or less than or equal to 100 MMBtu/hr and use low Nitrogen Oxide (NOx) burners;
  • Primarily burn pipeline natural gas, butane, propane or refinery fuel gas;
  • Use only diesel (<48 hours/year), butane, or propane as back-up fuel; and
  • Emit only fuel combustion products.

Additional information on the finalized rule can be found on IPCB's website at the links below.