Illinois Environmental Protection Agency (Illinois EPA) – St. Louis Nonattainment Area
The Illinois counties of Madison, Monroe, and St. Clair make up the Metro-East St. Louis ozone nonattainment area, which is classified as Serious nonattainment for ozone under both the 2015 8-hour ozone NAAQS.
Under the federal nonattainment New Source Review (NSR) program, new or modified major stationary sources of ozone precursors—nitrogen oxides (NOx) and volatile organic compounds (VOC)—must obtain Emission Reduction Credits (ERCs) to offset proposed increases in emissions. For a Serious nonattainment classification, the required offset ratio is 1.3 to 1. For example, a facility proposing to emit 100 tons per year (tpy) of NOx would need to secure 130 tpy of NOx ERCs.
| Pollutant | New Major Source Emission Rates | Major Modification to existing Source |
|---|---|---|
| Nitrogen oxides (NOx) | ≥50 tons/year | ≥25 tons/year |
| Volatile Organic compounds (VOC) | ≥50 tons/year | ≥25 tons/year |
Facilities that were emitting NOx and VOC may be eligible to generate Emission Reduction Credits (ERCs) with a permanent reduction of those emissions generating from a shutdown or installation of control technology or process change.
If your company has a new project that exceeds thresholds or had a facility with permanent reduction of emissions at any level, please reach out to see how Emissions Experts can assist.