Montana Air Quality Permit Application Addition of a New DAG, Updates to CO and NOx Limits, and MAQP Language Updates

Montana Air Quality Permit Application Addition of a New DAG, Updates to CO and NOx Limits, and MAQP Language Updates Public Notice Notice of Application for a Montana Air Quality Permit (MAQP), pursuant to Sections 75-2-211 and 75-2-215, MCA, and the Air Quality Rules). Calumet Montana Refining, will file on or about June 23, 2026 an application for a MAQP or a modification to an existing MAQP from the Montana Department of Environmental Quality (DEQ). Applicant(s) seeks approval of its application for: Calumet proposes to adjust the NOx emission limits on Hydrogen Plant #2 Reformer Heater (H-2815), update the CO emission limits on the FCCU Catalyst Regenerator, make the proposed updates (in Appendix D) to the MAQP language, and install a new dissolved air flotation (DAF) system to the existing wastewater treatment plant (Brief description of source for which permit is being applied, and a narrative description of the site location such as nearby towns, roads, landmarks, etc.) The legal description of the site is: Section 1, Township 20N, Range 3E in Cascade County, Montana. Within 40 days of the receipt of a completed application, DEQ will make a preliminary determination whether the permit should be issued, issued with conditions, or denied. Any member of the public with questions or who wishes to receive notice of the preliminary determination, and the location where a copy of the application and DEQ's analysis of it can be reviewed, or to submit comments on the preliminary determination, must contact DEQ at Department of Environmental Quality, Air Quality Bureau, Permitting Services Section Supervisor at P.O. Box 200901, Helena, MT 59620-0901, telephone (406) 444-3490. Any comments on the preliminary determination must be submitted to DEQ within the specified timeframe (within15 or 30 days after the preliminary determination is issued). MNAXLP June 23, 30, July 7 2026 LMTS0542667