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A Quick Guide for Completing your Illinois Annual Emissions Report (AER)

Posted: February 27th, 2023

Authors: Michael L. 

As environmental reporting season is now upon us, it is time to complete and submit your Annual Emissions Report (AER), which is due to the Illinois Environmental Protection Agency (Illinois EPA) by May 1st.  Here is a quick guide to help answer some of the questions you may have about this report and its requirements.

Do I have to file?

If you have, or are required to have, a State of Illinois air pollution operating permit, you are required to file an AER. This requirement is contained in 35 Ill. Adm. Code Part 254.

How do I begin?

Around February 1 of each year, the Illinois EPA will send you the forms necessary to be completed for the AER. To complete the report, you should have available items such as: your permit, records maintained throughout the year, emissions calculation references (e.g., AP-42, FIRE, etc.) and, if necessary, your permit application.  If you do not receive your forms from the Illinois EPA in the mail by mid to late February, contact them at EPA.AERQuestions@illinois.gov. Failure to receive the AER forms does not relieve you of the obligation to file a timely report.

Once you receive your forms, identify each emissions unit that is permitted. In many cases, your permit will specify or give you a general idea as to how to calculate your emissions. Use the data you’ve collected throughout the year and the calculation methods and references to calculate your actual emissions.

What if my AER forms information doesn’t agree with my permit or application?

If the AER forms information sent to you in the mail does not agree with your permit or application, e-mail the Agency at EPA.AERQuestions@illinois.gov with the specific issues and the Illinois EPA will work with you to resolve the discrepancies.

Does everyone complete the same type of report?

No. There are two types of reports. The “short” report requires the source to report emissions for the facility as a whole. The “long” report includes the short report and additionally requires a source to report emissions at the emission unit level.

What makes me qualify for the long report?

Sources that are required to complete the long report include:

  • all Clean Air Act Permitting Program (CAAPP) (or Title V) sources
  • sources whose total allowable emissions are >= 25 tons/year
  • sources who are in an ozone nonattainment area whose potential NOx or VOM emissions >= 25 tons/year

When determining what type of report the source must file, the Illinois EPA also looks at the values reported for the previous year. Therefore, if you reported total emissions >= 25 tons/year in the previous year but the database shows typical emissions < 25 tons/year, you will be required to file a long report.

What makes me qualify for the short report?

If you do not meet one of the requirements for submitting a long report, then you fall into the short report category. Sources that have been issued lifetime operating permits often fall into this category.

What emissions must be reported?

All sources must report annual actual emissions for regulated pollutants, which include criteria pollutants, hazardous air pollutants (HAPs), and greenhouse gases (GHGs) shown below. Emissions of HAP are to be reported only if there is a specific regulation (NESHAP or MACT) that applies to the source. For example, if your source is subject to the MACT for halogenated solvent cleaning, emissions of the HAPs used in that solvent cleaning must be reported.

Criteria Pollutants:

  • CO – Carbon Monoxide
  • LEAD – Lead
  • NH3 – Ammonia
  • NOX – Nitrogen Oxides
  • PART – Particulate Matter
  • PM10 – Particulate Matter < 10 microns
  • PM2.5 – Particulate Matter < 2.5 microns
  • SO2 – Sulfur Dioxide
  • VOM – Volatile Organic Material

Hazardous Air Pollutants (HAPs)

  • Individual HAPs regulated at your source by NESHAP, MACT or other regulations.

Greenhouse Gases (GHGs)

  • Carbon Dioxide (CO2)
  • Methane (CH4)
  • Nitrous oxide (N2O)

How do I request confidentiality?

Certain information requested in the AER forms may be claimed as trade secret, privileged information, or confidential only if the information does not represent “emissions data” as described in 40 CFR 56.7042. All claims of trade secret must comply with 2 Ill. Adm. Code 1827.201, Procedures for Claiming and Determining Trade Secrets. A claim of trade secret for data contained in an AER applies only to that report and must accompany the report. Any information claimed as a trade secret in the AER that also appears in other documents submitted to the Illinois EPA (such as permit applications), must be claimed under separate letter. A separate, edited version of the AER, omitting the confidential information, must be submitted to the Illinois EPA to provide a version of the report which may be inspected by the public.

Is there any other information that must be reported?

Title V permits (called Clean Air Act Permit Program (CAAPP) permits in Illinois), Federally Enforceable State Operating Permits (FESOPs), and Lifetime Operating permits commonly contain conditions specifying additional data or certification requirements that must be provided with the AER. For example, issued CAAPP permits require annual compliance certifications to be completed and filed with the AER. You should review your permit before completing the AER to ensure you are providing all the necessary information.

Where do I send the completed report?

After the AER has been completed and signed, mail the report to the address below:

ATTN: Annual Emissions Report
Illinois EPA
Bureau of Air
Air Quality Planning Section (#39)
1021 North Grand Avenue East
P.O. Box 19276
Springfield, IL 62794-9276

We hope this short guide helps you with completing your AER report.  Please contact Mike Liebert at mliebert@all4inc.com or 314-562-7925 or your ALL4 project manager for more information on AER reporting or for assistance in completing and submitting the report.


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