4 The record articles

CAO Reporting Year 2020 TAC Emissions Inventory Report

Posted: March 2nd, 2021

Authors: Dan D. 

The Cleaner Air Oregon (CAO) health-based air toxics regulatory program includes a provision [OAR 340-245-0040(2)] for all facilities with a Standard or Simple air contamination discharge program (ACDP) permit or a Title V air permit in Oregon to submit an updated toxic air contaminant (TAC) emissions inventory once every three years.  Reporting year 2020 (submitted in calendar year 2021) will be the first TAC emissions inventory required since the CAO rule was promulgated in 2018.  The reporting year also corresponds with U.S. EPA’s National Emissions Inventory (NEI) reporting year.  Most facilities received notice from the Oregon Department of Environmental Quality (DEQ) of the requirement to submit a TAC emissions inventory for reporting year 2020 in April 2020, a year ahead of the submission deadline of April 1, 2021.  However, in November 2020, Oregon DEQ extended the submission deadline until September 1, 2021 due to the widespread effects of Covid-19.

What exactly is this required submission? 

The TAC emissions inventory is a separate reporting requirement than the emissions inventory submitted for the CAO risk assessment which is the first step in the CAO risk assessment process after you are “called-in” to the program.  The 2020 TAC emissions inventory will be very similar to the emissions inventory required as part of the CAO risk assessment.  Oregon DEQ plans to provide an Excel-based reporting form in Spring of 2021 and has indicated that it will be very similar to the Excel-based reporting form for the CAO emissions inventory (AQ405CAO).

So, what should I be doing now if I want to be proactive?

Since the 2020 TAC emissions inventory will be very similar and can be used with very little updates to meet the first requirement once your facility is “called-in” to the CAO regulatory program, ALL4 recommends that facilities complete a Level I CAO risk assessment utilizing the TAC emissions calculated for the 2020 emissions inventory report.  The Level 1 CAO risk assessment is the most conservative (and simplest) option for satisfying the requirements of the CAO regulatory program.  The Level I CAO risk assessment utilizes the emissions rates along with stack height and distance to property line to characterize health risks for comparison to the CAO risk action levels (RAL).

And why exactly is that a good idea?

By conducting a Level 1 CAO risk assessment, now you can identify if any refinements need to be made to your 2020 TAC emissions inventory so that its ready to go once you’re “called-in” to the CAO regulatory program.  In addition, conducting a Level 1 CAO risk assessment will determine if your facility will need to conduct a more involved Level 2 or Level 3 CAO risk assessment, which involve the use of air dispersion modeling.  Lastly, refining your TAC emissions inventory now will allow you to do it at your own pace.  Once your facility is “called-in” to the CAO regulatory program, you will have 90 days to submit your emissions inventory (150 days if you’re conducting source testing).

If you need assistance preparing your 2020 TAC emissions inventory or would like to proactively conduct a Level I CAO risk assessment with the TAC emissions inventory you have prepared, please reach out to Dan Dix at ddix@all4inc.com or 610.422.1118.


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