Revised On: Aug. 1, 2024 - 1:00 p.m.

An emissions inventory (EI) is an accounting of all air pollutant emissions actually released into the atmosphere. This accounting forms the basis for air quality planning that occurs at county, state, and national levels. Pursuant to Arizona Administrative Code (A.A.C.), any source subject to a permit requirement may also be required to complete and submit an annual Emissions Inventory Questionnaire to ADEQ.

Proposed Federal Emissions Inventory Reporting Rule Changes

On July 23, 2023, EPA proposed changes to the federal Air Emissions Reporting Requirements (AERR) rules. These proposed changes included:

• Expanding mandatory reporting requirements to include hazardous air pollutants (HAPs)
• Changes to prescribed and agricultural burn information requirements
• Increase frequency of mandatory reporting to EPA from once every three years to every year
• Decrease the amount of time to prepare and submit annual emissions inventory information to EPA
• Provide options for how reporters provide the expanded information to EPA

Per the proposed rule, reporters will have to either report the additional pollutant information to and get support from the states or local agencies who will report to the EPA on their behalf OR report to the EPA with support from the EPA. The reporting method determined would apply to all reporters. ADEQ recently sent out a survey to reporters to determine their preference. The AERR rule has not been finalized by EPA.

For detailed information on the all of the changes included in the proposed rule amendment, visit EPA’s website | Visit Site >

Does my Facility Need to Report?

Some, but not all, ADEQ air permit holders are required to report their 2023 emissions. You may still be required to report emissions even if your permit is now closed. If you are unsure whether you are required to report your 2023 emissions, please download and consult the reporting guide | View/Download Guide >

For ADEQ rock products air general permit holders only:

Your year-end permit compliance certification process in myDEQ includes the review and certification of an EI report for the preceding year. Year-end compliance certifications must be completed in myDEQ each January. No additional annual EI reporting is required once that process is complete | Log In to myDEQ > | How to Get a myDEQ Account >

However, if you believe that the emissions estimates included in the myDEQ compliance certification are inaccurate and you would prefer to submit a separate report to supersede them, please follow the Class II permits reporting instructions below.

EI Reporting Forms

If you are required to report a 2023 emissions inventory, your report must be submitted by June 1, 2024. Facilities reporting using PDF or Excel forms should submit the completed, signed forms via email | Email >

Class I permits

• All class I air permit holders, as well as any operations which previously reported an EI to ADEQ using the State & Local EI System (SLEIS), must now report via the Combined Air Emissions Reporting System (CAERS). See the user application form or email us for additional details | View/Download > | Email >

Class II permits

• If you did not operate the entirety of 2023, use the Non-Operational Form | View/Download PDF >
• Otherwise, complete the preferred reporting form workbook per its README instructions | Download XLSX >
• If you do not have access to spreadsheet editing software, an alternative PDF version of the reporting workbook is available. You are not required to fill in the shaded bottom row of each worksheet | View/Download PDF >

Emissions Inventory Training

Help Videos

• US EPA training videos for CAERS | Visit EPA Website >  
• Preferred (.xlsx) reporting form | Coming soon
• Rock product general permit EIs | Coming soon

Workshops

• 2024 ADEQ Annual Emission Inventory Reporting Workshop for Submission by Preferred Reporting Forms or by myDEQ | View/Download Presentation > | Watch Video >
• 2024 ADEQ Annual Emission Inventory Reporting Workshop for Submission by CAERS | View/Download Presentation > | Watch Video >

Online Consultations 

ADEQ welcomes emission inventory reporters to schedule one-on-one online consultations with our staff. During the consultation, we can address emission inventory questions, clarify requirements, discuss inventory preparation and submission best practices, troubleshoot errors, etc. | Book a Consultation >

Guidance Documents

• Frequently Asked Questions | View/Download > 
• Cooling towers and the preferred (.xlsx) reporting forms | Download DOCM >
• Supporting documentation in a CAERS report | View/Download >
• Pipeline gas compressor station EI reporting | View/Download >
• Municipal solid waste landfill EI reporting | Coming soon
• Utility electric generating unit EI reporting | Coming soon

Questions?

Please email the inventory team | Email >