CAO Guide for Communities​

Purpose: Required forms and fees are submitted to DEQ. Existing facilities are called in from the order determined on the prioritization list and new facilities submit these at the beginning of their application process. 
Facility Role: Submitting required forms and fees 
DEQ Role: Contacting facility and technical support 
Outcome: Facility begins CAO process and starts the timeline for existing sources to submit their Emissions Inventory 
Additional Resources: 

• CAO Facility Prioritization Memo: provides an overview of the facility prioritization process 
• Facility Call-In Prioritization List: a list and summary of results for each facility for the prioritization process ​
  

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Purpose: The Emissions Inventory (EI) identifies all activities at a facility that emit Toxic Air Contaminants (TACs) - what pollutants are being emitted and how much. Information identified in the EI includes material and fuel usage, emissions control devices and their efficiencies, and daily and annual TAC emission rates. This emissions data is very important because it is used throughout the Risk Assessment process. 
Facility Role: Provide the detailed calculations and methodologies used to estimate those emissions. 
DEQ Role: Review emissions data for accuracy and ensure it represents the activities and materials at the facility. DEQ may require additional information including that the facility conduct source testing to obtain site-specific information needed to complete the EI. 
Outcome: A DEQ-approved EI with best available emissions data for a facility and its activities.  
Additional Resources: 

• Oregon Air Toxics Emissions Inventory Website 
• EPA Emissions Inventory Website 
• Source Sampling Manual  ​
  

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Purpose: In the Risk Assessment process, modeling is the tool we use to understand what amount of Toxic Air Contaminants (TACs) people living, working, or playing near facilities may be breathing. This modeling uses the emissions information from the EI in the previous step.  
Facility Role: Provide technical information to DEQ about where emissions are released at their facilities (for example, smokestacks), as well as meteorological and geographic information. This information includes stack heights and wind patterns, as well as distances to homes, businesses, and other locations where people spend many hours a day. In some cases, this also requires modeling facility operations under worst case emission scenarios to ensure health protectiveness.  
DEQ Role: Review technical information to ensure accuracy and make sure operating scenario represents potential worst-case emissions when required.
Outcome: An approved Modeling Protocol that combines the emissions data from the EI with information about where and how these emissions are released from the facility.  
Additional Resources:  

• AERMOD information from EPA 
• Recommended Procedures for Air Quality Dispersion Modeling   
• Recommended Procedures for Air Quality Dispersion Modeling  ​​​

Purpose: A work plan is required for more complicated risk assessments which are typically completed for larger, more complex facilities. The work plan includes more detailed information on the potential health risks to people nearby and how they may be exposed. 
Facility Role: Provide detailed information on how the facility will assess risk at locations surrounding the facility, which includes developing a conceptual site model for how communities may be exposed to Toxic Air Contaminant (TAC) emissions. 
DEQ Role: Review work plan to make sure that all of the potential health-based regulatory values and exposure locations in the community are accurately included in the assessment.  
Outcome: An approved Risk Assessment Work Plan that includes all potential routes of exposure and highlights where we may refine and update information in the assessment as new information becomes available that may change risk. ​

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Purpose: This step determines the facility’s compliance with Risk Action Levels and next steps which could include permit conditions to limit risk, installation of controls, or immediate risk reductions. For larger, more complex existing facilities, risk assessments can take up to five years.  
Facility Role: Facility uses all approved documents to model Toxic Air Contaminant (TAC) emissions and provide a final Risk Assessment report. 
DEQ Role: DEQ will review the final Risk Assessment report and determine appropriate next steps based on risk results. 
Outcome: Demonstrates the potential maximum risk for cancer and noncancer health risks to the community, and also indicates what further actions the facility must take based on these risk levels to meet the health-based standards of the program.  
Additional Resources: 

• Risk Action Level Flowchart  
• Hazard Index: How does CAO protect against noncancer health risk? 
• Cancer Risk: How does CAO protect against cancer health risk?​
  

Purpose: After the Risk Assessment is finalized, risk reductions may be required where risks exceed levels defined in rule. In these cases, DEQ would require a facility to submit a Risk Reduction Plan for review and approval outlining the steps they will take to reduce risks from Toxic Air Contaminant (TAC) emissions. In general, Risk Reduction Plans only apply to existing facilities.  
Facility Role: Determine how the facility will reduce risk to meet the program requirements and provide a timeline for implementing these reductions.  
DEQ Role: Review and approve the reduction plan to ensure that a facility is proposing the best available methods for reducing TAC emissions and can meet the program requirements in a timely manner.   
Outcome: An approved Risk Reduction Plan that lowers TAC emissions by installing emissions control devices, capturing fugitive emissions, or substituting less toxic fuels, materials, and chemicals in a process.  
Additional Resources:  

• EPA Resources on Emissions Controls ​
  

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Purpose: The CAO program works with DEQ's existing air quality permitting program to establish permit conditions that make sure that the facility's operations and activities continue to meet health-based standards. For new facilities, these conditions are included in the permit when issued. For existing facilities, the TACPA can be issued as a standalone document that will be incorporated into the air quality permit upon renewal.  
Facility Role: Applies for a TACPA and pays applicable fees.  
DEQ Role: Establishes CAO-specific permit conditions and requirements.  
Outcome: Some examples of permit conditions include setting source risk limits on emissions, material/fuel usage, or operations and activities. In many cases, DEQ also requires compliance testing, monitoring, recordkeeping, and reporting.  
Additional Resources: 

• AQ Permits Online ​
  

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Purpose: Once the Toxic Air Contaminant Permit Addendum or CAO permit conditions are finalized, the documents are put on public notice prior to issuance for review by the public. At this time, DEQ will take steps to notify the community when formal Community Engagement is required under the rules. In some cases, DEQ will hold a public meeting to share the results of the Risk Assessment and to discuss how the permit conditions were established.  
Facility Role: If required, a facility representative must attend a public meeting. Once issued, the facility must remain in compliance and notify DEQ and CAO of any changes that would impact emissions or risk.  
DEQ Role: Ensure compliance with permit conditions by reviewing annual reports, performing site inspections, and reviewing any testing or compliance demonstrations. 
Outcome: DEQ is able to issue permits that meet health-based standards.  ​

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