STACK Infrastructure (SI POR03, LLC)

The Emissions Inventory provides information on all the Toxic Air Contaminant emissions from a facility, and includes information on a facility’s operations and activities, as well as fuel and material usage rates. This is often the longest step in the CAO risk assessment process as DEQ needs to verify that all activities have been accounted for, and that the most representative emissions data available are used. In some cases, DEQ will require a facility to perform source testing at this stage if insufficient data is available to estimate emissions. ​

For an introduction to emissions inventories and why they matter, please see EPA's Fact Sheet. A facility-specific emissions inventory timeline and associated documents are linked below. 

Oct. 9, 2020: STACK Infrastructure submits Emissions Inventory 

April 2, 2021: STACK Infrastructure submits revised Emissions Inventory

• STACK Infrastructure emissions inventory

April 7, 2021: DEQ approves revised Emissions Inventory as part of Level 3 Risk Assessment​

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The Modeling Protocol provides information on how the facility plans to accurately model the concentrations of Toxic Air Contaminants (TACs) that community members may be exposed to based on the TAC emissions data from the approved Emissions Inventory. A Risk Assessment Work Plan is required for more complex Risk Assessments (Level 3 or Level 4) and provides more detailed information about locations where people live or normally congregate around the facility and how risk to these community members will be evaluated.​

Oct. 9, 2020: STACK Infrastructure submits Modeling Protocol and Risk Assessment Work Plan to DEQ 

April 2, 2021: STACK Infrastructure submits revised Modeling Protocol and Risk Assessment Work Plan to DEQ (includes March 7, 2021 cover letter)

• Revised STACK Infrastructure Modeling Protocol and Risk Assessment Work Plan​
  

April 7, 2021: DEQ approves Modeling Protocol and Risk Assessment Work Plan as part of Level 3 Risk Assessment​​​

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The Risk Assessment provides the summary of findings on potential risks to the surrounding community from emissions of Toxic Air Contaminants from this facility. The assessment indicates the exposure location(s) in the community with the highest potential Cancer and Noncancer health risk, and DEQ uses this information to regulate TAC emissions from the facility. In some cases, the risk may be very low, and no further action may be required, or the risk may exceed health-based standards where DEQ can require risk reductions. In most cases, permit conditions will be developed and included in a facility's air quality permit to regulate TAC emissions based on the results of the risk assessment.​

March 15, 2021: STACK Infrastructure submits Risk Assessment Report to DEQ 

April 2, 2021: STACK Infrastructure submits revised Risk Assessment Report to DEQ (includes March 7, 2021 cover letter)

• STACK Risk Assessment Report  ​
  

April 7, 2021: DEQ approves Risk Assessment Report as part of Level 3 Risk Assessment​

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​​April 7, 2021: DEQ approves Level 3 Risk Assessment

• STACK Infrastructure Risk Assessment Approval Letter
• STACK Infrastructure Risk Assessment Summary Results​​