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Cleaner Air Oregon Frequently Asked Questions For Facilities

Step 1: Call-In Information, Pre-Application Forms, Fees and Schedule

The CAO program rules were adopted in November 2018 and are applicable to all facilities that have, or are required to obtain, an Air Contaminant Discharge Permit[1] (ACDP) to operate. However, there are a few key points about how the program is being implemented that may affect when your facility goes through the CAO risk assessment process related to the type of permit, and whether your facility is defined as a New or Existing source under the CAO program [OAR 340-245-0020]:

Permit Types:

DEQ requires that all Simple ACDP, Standard ACDP and Title V permitted facilities perform a risk assessment. In most cases DEQ will not require General and Basic ACDP permitted facilities to perform a site-specific risk assessment.

New Facilities:

New facilities requesting any of the permit types listed above are required to perform a risk assessment prior to obtaining a DEQ air operating permit - in the case of the General ACDPs, please contact CAO staff. See the FAQ, “I'm a new facility, how do I know if I need to conduct a CAO risk assessment" below for more information.

Existing Facilities:

  • Existing facilities will be called in to the program in accordance with the Prioritization groupings, established by DEQ – these groupings may be subject to change based on revisions to potential risk estimates.
  • If a facility has already completed an approved risk assessment, construction permit approval for new TEUs may require additional risk analysis as well as permit modifications. See the FAQ, “How are permit modifications handled under CAO," below for more information.
  • DEQ, at its discretion, may call in any existing facility to complete a risk assessment. Factors considered in the decision may include understanding potential risks, obtaining new information about facility emissions, permitting needs, or in response to community concerns.

[1] - DEQ also has the authority to require unpermitted facilities to perform a risk assessment if a potential significant health risk is anticipated from operations and activities.


In general, the criteria for determining if a facility is new or existing is defined in OAR 340-245-0020, and are as follows:

  • Existing source – either commenced construction or submitted all necessary applications to DEQ under OAR 340 divisions 210 or 216, and they were deemed complete, before Nov. 16, 2018.
  • New source – there are multiple cases where a facility may be considered new under the CAO program:
    • The facility does not meet the criteria listed above for an existing facility;
    • The facility was an existing facility, but that is relocating; or
    • There may be instances where it is unclear if the above criteria are met (e.g., a facility is adding or changing operations, and/or changing the facility type) -  in those cases please contact DEQ for a determination.

Once a facility has been determined to be either a new or existing facility, there are aspects of the CAO rules and process that apply differently to each type of facility:

New facilities:

  • CAO risk assessment may be required to complete an ACDP application (See the FAQ below titled “I'm a new facility, how do I know if I need to conduct a CAO risk assessment," for more information)
  • No enforceable deadlines for CAO process
  • Lower (more stringent) Risk Action Levels[1]

Existing facilities:

  • CAO risk assessment not required until facility is called in to program by DEQ
  • Enforceable deadlines for CAO submittals [OAR 340-245-0030]
  • Higher Risk Action Levels

[1] – Risk Action Levels (RALs) are the risk levels, above which, a facility will be required to take specific action – e.g., formal Community Engagement or risk reduction.

DEQ has published the facility prioritization results. All the facilities in Group 1 have been called-in prior to 2023 and have either completed, or are still undergoing, the CAO process. Facilities in Group 2 can expect to be called in starting in mid-2023. Remaining facilities will be called-in as resources allow.

Once an Existing source is called-in to the program, the following submittal deadlines apply [OAR 340-245-0030]:

  • CAO Pre-Application AQ500 Form and Fee: 30 days after Call-in
  • Emissions Inventory AQ520 Form: 90 days after Call-in[1]
  • Modeling Protocol: 30 days after approval of the Emissions Inventory
  • Risk Assessment Work Plan (Levels 3 and 4): 60 days after approval of the Emissions Inventory
  • Risk Assessment:
    • Levels 1 and 2: 60 days after approval of the Modeling Protocol
    • Level 3: 120 days after approval of the Risk Assessment Work Plan
    • Level 4: 150 days after approval of the Risk Assessment Work Plan
  • Risk Reduction Plan (if required): 30 days after approval of the Risk Assessment

[1] – If a source requests to source test, then the Emissions Inventory, Modeling Protocol, and Risk Assessment Work Plan (as applicable) are due 150 days from the Call-in.

If a new facility emits Toxic Air Contaminants (TACs) and is applying for a Simple or Standard Air Contaminant Discharge Permit (ACDP), it will be required to conduct a CAO Risk Assessment. Facilities requesting Basic and other General ACDP permit types will likely not be required to perform a site-specific Risk Assessment before obtaining a permit. A new facility should work with CAO staff to determine if a CAO Risk Assessment is required – inquiries may be submitted to cleanerair@deq.oregon.gov.

If you are required to conduct a Risk Assessment, you may submit the ACDP application for your facility at the same time the initial CAO documents are submitted, and DEQ may review the ACDP application materials concurrently with the CAO process. Please note that the ACDP application for your facility is not considered complete until after DEQ has approved your final Risk Assessment and all CAO Specific Activity Fees have been submitted (see OAR 340-216-8030 Table 3). Additionally, information learned during the CAO process may result in changes to the type of ACDP and fees required (for example, a previous Simple or Standard ACDP determination could be revised based on submitted application and CAO materials).​

Whether you are an Existing source that has been called-in to the CAO program, or a New source applying for an air quality permit, the forms and fees that are initially required are:

The CAO Pre-Application AQ500 form requires standard facility information as well as indicates the required fee – either the Existing Source Call-In Fee or the New Source Consulting Fee. For Existing sources, the CAO Pre-Application AQ500 Form and Existing Source Call-in Fee is due 30 days after the date DEQ issues the call-in letter for that facility. For New sources, DEQ must receive the CAO Pre-Application AQ500 Form and New Source Consulting Fee before beginning the CAO review process.

Upon completion of the CAO process, facilities will submit a CAO Permit Application AQ501 Form. This form indicates whether a source has been determined to be either an Exempt or a De minimis source under CAO. [OAR 340-245-0020] It also provides a checklist to ensure that all the submittals and information required under the CAO program have been submitted. Finally, it includes the CAO Specific Activity fees, which are due at the time of submitting the AQ501 form. For more information on these fees see OAR 340-245-0400 and/or contact CAO staff. IMPORTANT – a New source's ACDP application will not be considered complete until the CAO Permit Application AQ501 Form and all fees have been submitted.

After the CAO process has been completed, a facility may need to construct new equipment or modify current equipment or operations and activities. In these cases, sources may need to re-evaluate risk and be required to apply for a permit modification. When applicable, a source must submit the CAO Permit Modification AQ502 form and required modification fees – see the FAQs, “How are permit modifications handled under CAO," and “What fees are required for permit modifications after an initial CAO Risk Assessment has been approved," for more information.

Finally, there are CAO Annual fees, which Existing sources are already paying, and New sources pay with their ACDP application fees – all permitted facilities pay this annual fee.​

All CAO forms are located on the “Simple, Standard and Construction ACDP Application and Reporting Forms" web page. CAO forms are listed as the AQ500-series forms.​​

DEQ strongly encourages facilities to setup a pre-application meeting with their regional DEQ Air Quality staff, as well as CAO staff, to make certain all the required information, documents, and fees are submitted to ensure an efficient permitting process.

After the pre-application meeting, begin your application by submitting the “CAO – New/Reconstructed Source Risk Assessment Application" and “New Source Consulting Fee" through Your DEQ Online. See the Air Quality Permits in Your DEQ Online webpage for more information about Your DEQ Online, including user guides.

The CAO Emissions Inventory AQ520 form, Categorically Exempt Toxics Emissions Units (TEUs) AQ523 Form, and all required supporting technical materials must be submitted through the application in Your DEQ Online – see the Step-by-Step guide for more information. If you need to submit information that you are unable to provide electronically, please contact your CAO Project Manager or email cleanerair@deq.oregon.gov.​


Sources that have been notified that they are required to submit a Risk Assessment that have not yet been issued a permit with CAO conditions or a Toxics Air Contaminant Permit Addendum (TACPA), and that are proposing to construct new equipment or modify existing equipment or operations that could increase Toxic Air Contaminant (TAC) emissions, must revise and resubmit any materials in order to include the modifications in the permit or TACPA – e.g., Emissions Inventory or Modeling Protocol.

Sources that have been issued a permit with CAO conditions or a TACPA, and are proposing to modify equipment or operations, may be required to apply for a permit modification under Oregon Administrative Rule (OAR) 340 division 216 or 218. In most cases if you have previously completed a Risk Assessment under CAO, your permit or TACPA has CAO general conditions that describe modifications that may require a permit modification. These conditions are based on the CAO rule language in OAR 340-245-0100(8) and include the following:

  • Construct or modify an Aggregate or Significant TEU (in some cases Exempt TEUs may also qualify, check with CAO staff)
  • Modify an established Source Risk Limit
  • Request an extension to a compliance date or terminate postponement of risk reduction
  • Modify any physical feature of the facility that was used as a modeling parameter (e.g., fence lines, building/stack heights, or relocation of a stack by more than 10 meters)
  • Zoning or land use changes near the facility have changed in a way that could increase risk
  • Modify air monitoring requirements required under CAO
  • Revise or update the approved Risk Assessment after becoming aware of the need for corrections or revisions

In the case where a revised Risk Assessment must be submitted for the proposed changes, you must follow all the procedures outlined in OAR 340-245-0050, which requires submittal of all applicable technical documents and their accompanying background information for review and approval prior to approval of the proposed modifications – this includes the Emissions Inventory, Modeling Protocol, Risk Assessment Work Plan (if submitting a Level 3 or 4 Risk Assessment), and the Risk Assessment. Please note that for Existing sources under CAO, the submittal deadlines in OAR 340-245-0030 do not apply to submittals for the modifications made after issuance of a TACPA or permit that includes CAO conditions.

Sources submitting CAO documents for the purposes of a risk re-evaluation and/or permit modification should submit the "CAO-Risk Reassessment/Mofication Application" through Your DEQ Online, including CAO Permit Modification AQ502 Form.  You may submit all technical documents at the same time for review​. Required fees will be assessed after the initial application and AQ502 submittal (see the FAQ, “What fees are required for permit modifications after an initial CAO Risk Assessment has been approved"). 

If you have determined that you are required to submit a CAO Permit Modification AQ502 Form for proposed changes at your facility (see FAQ, “How are permit modifications handled under CAO"), the following fees may apply.

  • Re-evaluation of Risk Assessment may require the following Specific Activity Fees:
    • TEU Risk Assessment[1] – no permit mod (#16)
    • TEU Risk Assessment – permit mod (#17)
    • Level 2 Modeling review only for TEU approval (#18)
    • Level 3 Modeling review only for TEU approval (#19)
    • Source Test Review Fee (plan and data review) – simple to complex (#23-#25)
    • Community Engagement Meeting Fee – low to high (#20-#22)
    • TBACT/TLAER Review (per Toxic Emissions Unit and type of Toxic Air Contaminant) (#15)
  • If a permit modification is required based on the results of the revised Risk Assessment, then the applicable Toxic Air Contaminant Permit Addendum (TACPA) modification fee [OAR 340-216-8020 Table 2, Part 4] must also be submitted - please refer to OAR 340-245-0100(8)(f)&(g), or consult with DEQ to determine the appropriate fee:
    • Basic/Non-technical Fee
    • Moderate Technical Fee
    • Complex Technical Fee

Below are examples of fee requirements for different cases where a facility is proposing modifications after previously completing an approved Risk Assessment under CAO. Please consult with CAO staff if you need further clarification.

Example 1: Constructing new TEUs with increase in risk but not above previous Risk Action Level

An existing source that was previously issued a TACPA (i.e., not determined to be an Exempt or De minimis source) after completing a Risk Assessment is proposing to add two new Significant Toxics Emissions Units (TEUs) that emit Toxic Air Contaminants (TACs). The facility is submitting a revised Level 3 Risk Assessment that demonstrates a minor increase in risk, but that does not cause the source risk to exceed the previous Community Engagement Risk Action Level (RAL). The following fees apply:

  • Moderate Technical TACPA fee – because the addition of new TEUs likely requires new permit conditions, but the risk did not exceed a higher RAL than the original Risk Assessment.
  • TEU Risk Assessment fee[1] – permit mod (Specific Activity fee #17)
  • Level 3 Modeling review only for TEU approval (Specific Activity fee #19)
  • Community Engagement Meeting Fee – low (Specific Activity fee #22) – because DEQ previously required a community meeting when the original TACPA was issued, and will only require mailing a postcard for this modification.

Example 2: De minimis source constructing new TEUs, new risk exceeds Toxics Lowest Achievable Emission Rate RAL

A new source that was previously determined to be a de minimis source is proposing to add seven new TEUs (three “Type A" TEUs and four “Type B" TEUs) - previously this source was only operating one “Type A" TEU. The submitted Risk Assessment indicates the risk is above the Toxics Lowest Achievable Emissions Rate (TLAER) RAL. The following fees apply:

  • Complex Technical TACPA fee
  • TEU Risk Assessment fee – permit mod (Specific Activity fee #17)
  • Level 3 Modeling review only for TEU approval (Specific Activity fee #19)
  • Community Engagement Meeting Fee – high (Specific Activity fee #22) – DEQ would require a community meeting
  • TBACT/TLAER Review (per Toxics Emissions Unit and type of toxic air contaminant) (Specific Activity fee #15) – this fee will be required each for “Type A" and “Type B" TEUs, and once again as the emit both volatile TACs and particulate heavy metal TACs, requiring separate control technologies for each type of TAC.

Example 3: Source testing data used to update production limits

An existing source performs source testing that demonstrates the TAC emission estimates used in the Risk Assessment were much higher than observed in the site-specific test results. The testing required more than one test method be performed to obtain these results. The source submits a revised Level 3 Risk Assessment using the new emissions data, along with increased activity levels for the TEU. This increased activity is greater than the levels allowed under the current permit but does not increase risk above the original Risk Assessment, which was below the Community Engagement RAL. The following fees apply:

  • Basic Technical TACPA fee
  • TEU Risk Assessment fee – permit mod (Specific Activity fee #17)
  • Level 3 Modeling review only for TEU approval (Specific Activity fee #19)
  • Source Test Review Fee (plan and data review) – moderate (Specific Activity fee #24) – this is a moderate fee because it was a single TEU that required multiple testing methods.

Example 4: Constructing new TEUs, risk does not exceed de minimis RAL

A new source was determined to be a de minimis source based on its approved Level 1 Risk Assessment. This source is proposing to add a new TEU and submits a revised Level 1 Risk Assessment that demonstrates that the risk does not increase above the de minimis RAL (note: all TEUs must be modeled at capacity [see OAR 340200-0020(19) & OAR 340-245-0020(14)]). The following fees apply:

  • No TACPA fee required
  • TEU Risk Assessment fee – no permit mod (Specific Activity fee #16)

[1] – For the purposes of the review of revised Risk Assessments for changes proposed at facilities, the Specific Activity fees #16 and #17 can refer either to a single TEU review or a facility-wide risk re-evaluation.


For New facilities, the CAO Risk Assessment process and ACDP application technical review and permit drafting should take place concurrently – the best way to ensure this is to submit the applicable ACDP application at the time that you submit your CAO - New/Reconstructed Sourse Risk Assessment Application" in Your DEQ Online​. Once the CAO process is complete and DEQ has approved the risk assessment for your facility and received both your CAO Permit Application AQ501 Form and required Specific Activity fees [OAR 340-216-8030 Table 3], the ACDP application is considered complete and the ACDP permitting process can continue.

For Existing facilities called-in to the program in accordance with their Prioritization grouping, any CAO permit conditions required to limit risk based on the results of the Risk Assessment will be added either as a Toxic Air Contaminant Permit Addendum (TACPA) or directly into the permit if it is being renewed, and ultimately included in the permit upon renewal. If a facility's permit is up for renewal and has recently been called in to the CAO program, there may be a delay in the renewal timeline if DEQ requires the Risk Assessment be completed prior to renewal.​


In general, the CAO submittal review and approval process is structured so that DEQ will provide formal comment and approval letters in response to CAO submittals; these formal communications, along with the final, approved submitted documents will be made publicly available on the CAO facility webpages (see Community Engagement FAQ).

For existing facilities, this review and approval process has deadlines, extension request requirements, and corrective actions specified in rule [OAR 340-245-0030​]. Documents are required to be submitted on time unless an extension is granted. These rules provide enforceability around submittal deadlines and grant DEQ the authority to request additional information or corrections, or make updates as needed to approve any of the required CAO submittals. These rules also detail the process for requesting an extension to any of the deadlines established for an existing facility's submittals.​

All Cleaner Air Oregon specific activity fees can be found in the Cleaner Air Oregon Specific Activity Fees table. [OAR 340-216-8030 Table 3]

  • Pre-Application fees:
    • For New facilities in CAO, the “New Source Consulting Fee" is required at the time of submittal of the “CAO – New/Reconstructed Source Risk Assessment Application" in YDO. See the New Source Workflow for New Facilities.
    • For Existing facilities in CAO, the “Existing Facility Call-in fee" is due 30 days after the notice date on the call-in letter. [OAR 340-245-0400(3)]. See the Existing Source Workflow for Existing Facilities.
  • Application and Specific Activity fees: All applicable fees are due at the time of submittal of the Permit Application (AQ501) form. [OAR 340-245-0400(4) and (5)] For existing facilities, payment deadlines specific to Cleaner Air Oregon requirements may vary, please review OAR 340-245-0030.​
  • Annual fees: For new facilities, CAO annual fees must be submitted with the ACDP application, and this first payment will be for the full year, with the next payment pro-rated for the duration of operation in the first fiscal year. [OAR 340-216-8020 Table 2] The CAO Annual fees have already been included in the Annual fees submitted by existing facilities.

DEQ may request technical information related to a required submittal for the CAO program from both new and existing facilities in order to approve a document. The following outcomes may occur depending on the response made by the facility:

  • The information is provided, and the document approved.
  • The information is not provided in a timely manner.
  • The information provided is incomplete, inaccurate, or otherwise does not satisfy the request, and DEQ is unable to approve the document, then DEQ may:
    • Request the information again by date certain;
    • Modify the submittal for approval, with sufficient factual basis – the facility is then responsible for paying the Document Modification Fee [OAR 340-216-8030 Table 3]; or
    • Take an enforcement action, including assessing civil penalties and other potential consequences.

In cases where a facility anticipates that a submittal deadline may not be met, extensions can be requested for good cause if reasonable progress can be demonstrated. Extension requests must be submitted no fewer than 15 days prior to the submittal deadline to be considered by DEQ. [OAR 340-245-0030(3)] Failure to submit a timely request for extension or to meet reasonable progress and good cause requirements will result in DEQ's denial of an extension request. If the extension request is denied, any submittals not meeting the established deadlines in OAR 340-245-0030(1) or (2) constitute a violation of DEQ rules and may result in DEQ taking an enforcement action, including assessing civil penalties, and other potential consequences. [OAR 340-245-0030(4)]​


Cleaner Air Oregon frequently asked questions for facilities 

The frequently asked questions (FAQs) on this page are provided to answer common questions about completing air toxics risk assessments for the Cleaner Air Oregon program, and ensure consistency across assessments. As the Cleaner Air Oregon process evolves, DEQ will update this page with common questions or unique scenarios. If there is a question you would like to see answered or have feedback on a response below, please contact us at cleanerair@deq.state.or.us.

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