Metro-East Area

The USEPA has approved the Illinois Environmental Protection Agency's (Illinois EPA's) request submitted on May 8, 2017 to re-designate Illinois' portion of the St. Louis area (i.e., Metro-East area) to be in attainment of the 2008 Ozone National Ambient Air Quality Standards (NAAQS). The Metro-East area consists of Madison, Monroe and St. Clair Counties.

This proposal is based on the review of the 2014-2016 Ozone monitoring data which is complete, quality-assured and certified for the Metro-East Area. The USEPA is proposing this recommendation as the Metro-East area meets the applicable statutory requirements for re-designation under the Clean Air Act (CAA). In addition, the USEPA is proposing to approve the following as a revision to the Illinois State Implementation Plan (SIP).

  • Illinois' Plan for maintaining the 2008 Ozone NAAQS through 2030 in the St. Louis area.
  • Illinois' 2030 Volatile Organic Matter (VOM) and Nitrogen Oxides (NOX) Motor Vehicle Emission Budgets (MVEBs) for the Metro-East area.

This rulemaking has been published as a proposed rule in the federal register (82 FR 57892). Comment period ends on January 8, 2018.

Chicago Area

The USEPA is evaluating the non-attainment designations for the 2008 Ozone NAAQS for the Chicago non-attainment area. It is anticipated that the Chicago area will not attain the 2008 Ozone NAAQS (75 ppb) by the July 2018 deadline based on monitoring data from 2015 to 2017. If attainment cannot be demonstrated, the USEPA will reclassify the Chicago area as "serious" non-attainment for the 2008 Ozone NAAQS. The Chicago area is currently classified as "moderate" non-attainment. This reclassification may become effective as early as January 2019.

Be sure to keep an eye on the 3-year average monitoring data as the reclassification to "serious" non-attainment would result in the following changes:

  • Title V major source threshold will be 50 tons per year (tpy) for VOM and NOx (currently the threshold is 100 tpy); and
  • New Source Review (NSR) major modification threshold will be 25 tpy, aggregated over 5-years (currently the threshold is 40 tpy).

Keep in mind that this change in attainment status could impact upcoming projects at your facility!