The Chicago-Naperville, IL-IN-WI ozone nonattainment area failed to attain the 2008 ozone NAAQS by the attainment date of July 20, 2018. The area, which is currently classified as “Moderate” for the 2008 ozone NAAQS, will automatically be bumped-up to a “Serious” classification upon the effective date of the final reclassification notice. The Chicago area joins six (6) other Moderate areas that likewise failed to attain the standard, including Dallas-Fort Worth, TX; Greater Connecticut, CT; Houston-Galveston-Brazoria, TX; Nevada County (Western part), CA; New York-North New Jersey-Long Island, CT-NY-NJ; and San Diego County, CA.

The U.S. Environmental Protection Agency (USEPA) published a proposed rule of the reclassification on November 14, 2018. The reclassification is based on ozone monitoring data for the years 2015-2017. The bump-up to a Serious classification will give Illinois, Wisconsin and Indiana until July 20, 2021 to attain the standard. These states will be required to submit to USEPA the SIP revisions for these areas that meet the requirements applicable to “Serious” areas under Section 182(c) of the Clean Air Act. USEPA is proposing in the rule to allow the states up to 12 months after the effective date of the final reclassification notice to submit SIP revisions for non-RACT requirements and until August 3, 2020 to submit RACT SIP revisions.

The effect of failing to attain the standard is significant for owners or operators of sources in the area that emit volatile organic compounds (VOCs) or nitrogen oxides (NOx). The main impacts of the reclassification include: (a) the Title V major source threshold will be going from 100 tpy to 50 tpy; (b) the new source review major modification threshold will be going from 40 tpy to 25 tpy aggregated over 5 years; (c) the emissions offset requirements will be going from 1.15 to 1, to 1.2 to 1; and (d) new RACT requirements may be implemented to control sources emitting between 50 to 100 tpy.

With the lowering of the Title V major source threshold, sources should begin to seek emission reductions and permit revisions to stay below the new 50 tpy threshold. Sources that cannot stay below the major source threshold will need to apply for and obtain a Title V permit. Sources should also be considering the new source review and major source threshold changes when planning upcoming projects at your facility.

USEPA is accepting comments on the proposed rule by December 14, 2018. Assuming no public hearing is held, the automatic bump-up could happen as early as February 2019. We will continue to keep you apprised of developments as they occur.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.