EPA Air · inspections by county and year
Air-emissions inspections in Yellowstone County, Montana, 2025
- 5Inspections
A compliance evaluation is the on-site or file review a state, local or federal air agency records against a permitted source. Each row below is one inspection recorded against a source in Yellowstone County, Montana during 2025. A facility can appear several times: this is the year’s record of what happened, not a list of places. The sources themselves are on the Yellowstone County facility page.
Yellowstone County, Montana, 2025
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Air-emissions inspections in Yellowstone County, other years
Air-emissions inspections recorded in Yellowstone County, Montana, 2025
| Date | Facility | Kind | Agency |
|---|---|---|---|
| 2025-11-05 | YELLOWSTONE COUNTY GENERATING STATION | FCE On-Site | State |
| 2025-09-29 | BILLINGS REFINERY | FCE On-Site | State |
| 2025-09-23 | MONTANA SULPHUR & CHEMICAL | FCE On-Site | State |
| 2025-08-26 | WESTERN SUGAR COOPERATIVE — high-priority violation on file | FCE On-Site | State |
| 2025-05-29 | YELLOWSTONE POWER PLANT — high-priority violation on file | FCE On-Site | State |
Dates as filed by the agency that recorded the inspection. Figures from EPA’s ICIS-AIR download.