Air Quality | Calumet Montana Refining LLC- Calumet Montana Refining| Public Comment Period Ends May 4, 2026

The Department of Environmental Quality has prepared a Draft Operating Permit #OP2161-23, for Calumet Montana Refining LLC –Calumet Montana Refining.

Location:

• 1900 10th Street Northeast, Great Falls, MT 59404
• Cascade County

Associated Materials:

• OP2161-23  
• TRD2161-23

Comment Period Ends:                             

• May 4, 2026 11:59PM

Send Comments To:

• Craig Henrikson

OR

• DEQ Air Quality Bureau
  PO Box 200901
  Helena MT 59620-0901

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Tags: Public Comment and Air