Step-by-Step Guide for Facilities

• Pre-Application Fee form (AQ500 and instructions)
• Permit Modification form (AQ502)
  
• Specific activity fee tables (Activities 1 through 3)
• ACDP Application (Instructions for Air Contaminant Discharge Permit Application Forms)
  
• CAO Annual and TACPA Modification Fees OAR 340-200-8020 Table 2​
  
• CAO Fee Guide​
  

​The Emissions Inventory submittal (AQ520) identifies all toxic emission units, process activity levels, toxic air contaminants, appropriate emission factors, material balance, and emissions calculations (including assumptions, references and methodologies). At this stage, DEQ or the facility determines if source testing will be conducted to complete the Emissions Inventory.

Provide the following information when submitting your Emissions Inventory:

• Required Forms:
• AQ520 Cleaner Air Oregon Emissions Inventory
• AQ523 Categorically Exempt Toxics Emissions Units
• Detailed Process Flow Diagram that indicates:
  
• All material flows (e.g., feedstock, fuel, and waste materials)
  
• Operational information (e.g., Batch/Continuous, operating temperatures, startup/shutdowns)
  
• Emission release points for all toxic air contaminant emissions – these must correspond to stack and fugitive modeling input parameters
  
• Activity by TEU (e.g., actual, requested potential, capacity, maximum daily)
  
• Identification of:
  
• Toxic Air Contaminants (TACs) by TEU
  
• Control devices and efficiencies by TEU
  
• Emission factors by TEU
  
• Material balance emission approach by TEU
  
• Emission factors with references and/or background data and calculations
  
• Documentation for material balance emission estimates (e.g., all Safety Data Sheets)
  
• Sufficient documentation to determine if an activity qualifies as an Exempt TEU (see Exempt TEU Reporting)
  
• Source testing data (if applicable)
  
• All toxic air contaminant emissions from all Aggregated and Significant TEUs
  
• Technical documentation related to air pollution control device operation and efficiency (e.g., manufacturer or source test data)
  

Resources available to assist facilities in the Emissions Inventory process include:  

• Reporting list for all toxic air contaminant emissions: Toxic Air Contaminant Priority List​ [OAR 3​40-247-8010 ​Table 1]
  
• Emissions Inventory reporting resources:​ Oregon Air Toxics Reporting site
• Source Testing Rules: Source Sampling Manual
  
• Identification of Toxic Emission Units (TEUs) (Quick Guide)​​
  

Additional information, including emission factor resources and source testing can be found on the FAQ page.

​The modeling protocol specifies the risk assessment level selected, facility and source characteristics, modeling assumptions, and receptor placement. The risk assessment level selected is based on the complexity of the facility and the toxic air contaminants released.  If conducting a level 1 or level 2 risk assessment, the modeling protocol will include stack height, building information, and the distance to residential, worker, child, and acute exposure locations. For level 3 or level 4 risk assessments, some of this information will be included in the risk assessment work plan. A risk assessment work plan and modeling protocol can be submitted as a single document to reduce redundancy.

Resources available to assist facilities include:

• Recommended Procedures: Air Quality Dispersion Modeling Recommended Procedures
• Dispersion Model Selection (Section 2.5)
• Project Description (Section 2.1)
• General Modeling Components including source characterization, downwash considerations (if applicable) and urban/rural designation (Section 2.2)
• Complex Terrain Considerations (Section 4.3.5)
• Meteorological Data (Section 2.3)
• Receptor Placement/Modeling Domain (Section 2.4)
• Quick Reference Guides
• Identification of Toxic Emission Units (TEUs) (Quick Guide )
• Select Emissions Approach (Quick Guide)
• Toxic Air Contaminant Conversion Table
• Dispersion Factor Tables for Modeling Emissions for a Level 1 Risk Assessment [OAR 340-245-8010 Table 3]
  

More information can be found on the FAQ page.

​​A risk assessment work plan is required for a level 3 or a level 4 risk assessment. The work plan outlines how exposure locations will be assigned, and how risk will be calculated from modeling results. The risk assessment work plan and modeling protocol can be submitted as a single document to reduce duplication.

Resources available to assist facilities include:

• Recommended Procedures: Health Risk Assessment Recommended Procedures 
• Exposure Location Assignment (Quick Guide)
• Residential
• Worker
• Child
• Acute

• State Zoning to Exposure Location Crosswalk
• Exposure Location Change Request Form (AQ521) and Table (AQ 522)
  
• RBCs (Toxicity Reference Values and Risk Based Concentrations Spreadsheet) 
• Reporting risk by target organ​ (if applicable) (Simple Version, Complete Version)
• Existing Facility Hazard Index Calculations and Noncancer Risk Action Levels (Quick Guide)

More information can be found on the FAQ page

​​Risk is calculated following the procedures outlined in the DEQ approved modeling protocol and risk assessment work plan. Please refer to the Health Risk Assessment Recommended Procedures for example risk calculations and information on the following report elements to include.

• Recommended Procedures: Health Risk Assessment Recommended Procedures
• Modeling results by exposure location
• Risk calculations
• Reporting risk by Exposure Scenario
• Reporting risk by target organ (if applicable) (Target Organ Spreadsheet)
• Comparing calculated risk to RALs ([OAR 340-245-8010] Ta​ble 1​)
• Risk assessment uncertainty analysis
• Examples of Risk Calculations from Appendix A 
• Quick Reference Guide
• Reporting Risk by Toxic Emission Units (TEUs) (Quick Guide) 

More information can be found on the FAQ page.

​While community engagement may take place throughout the risk assessment process, the results of the approved risk assessment indicates whether a facility's source risk has exceeded the formal community engagement risk action level​ [OAR 340-245-8010 Tab​le 1]. 

If this risk action level is exceeded, the facility must participate in and fund community engagement to inform the public of its potential risk. DEQ will work with the facility to implement community engagement and determine what level and fees are required.

​More information can be found on the FAQ page.

​If the results of the approved risk assessment indicate risk above the TBACT or TLAER risk action level an analysis of all significant TEUs is required and may lead to the implementation of emission controls. See OAR 340-245-0220 for more details.

If the results of the approved risk assessment indicate risk above the mandatory risk reduction level, in addition to TBACT analyses, a risk reduction plan must be approved and implemented – there are different timelines for chronic or acute risk reductions. See OAR 340-245-0130 for more details.

More information can be found on the FAQ page.​

​​A facility may choose to conduct monitoring based on the results of the risk assessment. Monitoring data may be used to update the risk assessment. For assistance on monitoring, contact cleanerair@deq.oregon.gov or your permit writer.

More information can be found on the FAQ page.​

​​Once DEQ has approved the facility risk assessment and any subsequent submittals (e.g., risk reduction plan, ambient monitoring plan, etc.), the CAO Permit Application Form AQ501 must be submitted with all applicable fees​.

​Once the results of the risk assessment are complete, DEQ will develop permit conditions that ensure continued compliance to maintain health protective risk levels. These conditions may vary by facility. Some common permit conditions include limits on emissions, operational parameters, production activities, or fuel/raw material usage. Source testing may also be required to demonstrate compliance with these conditions.