EPA Air · stack tests by county and year
Air-emissions stack tests in Glacier County, Montana, 2025
- 22Stack tests
A stack test measures what a source actually emits, at the stack, against the limit in its permit. Each row below is one stack test recorded against a source in Glacier 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 Glacier County facility page.
Air-emissions stack tests in Glacier County, other years
Air-emissions stack tests recorded in Glacier County, Montana, 2025
| Date | Facility | Kind | Agency |
|---|---|---|---|
| 2025-10-06 | NORTHWESTERN ENERGY MAINLINE #1 | Pass | State |
| 2025-10-06 | NORTHWESTERN ENERGY MAINLINE #1 | Pass | State |
| 2025-10-06 | NORTHWESTERN ENERGY MAINLINE #1 | Pass | State |
| 2025-10-06 | NORTHWESTERN ENERGY MAINLINE #1 | Pass | State |
| 2025-10-06 | NORTHWESTERN ENERGY MAINLINE #1 | Pass | State |
| 2025-10-06 | NORTHWESTERN ENERGY MAINLINE #1 | Pass | State |
| 2025-04-23 | NORTHWESTERN ENERGY MAINLINE #1 | Pass | State |
| 2025-04-23 | NORTHWESTERN ENERGY MAINLINE #1 | Pass | State |
| 2025-04-23 | NORTHWESTERN ENERGY MAINLINE #1 | Pass | State |
| 2025-04-23 | NORTHWESTERN ENERGY MAINLINE #1 | Pass | State |
| 2025-04-23 | NORTHWESTERN ENERGY MAINLINE #1 | Pass | State |
| 2025-04-23 | NORTHWESTERN ENERGY MAINLINE #1 | Pass | State |
| 2025-03-10 | COBB STORAGE FIELD STATION 017 | Pass | State |
| 2025-03-10 | COBB STORAGE FIELD STATION 017 | Pass | State |
| 2025-03-10 | COBB STORAGE FIELD STATION 017 | Pass | State |
| 2025-03-10 | COBB STORAGE FIELD STATION 017 | Pass | State |
| 2025-03-10 | COBB STORAGE FIELD STATION 017 | Pass | State |
| 2025-03-10 | COBB STORAGE FIELD STATION 017 | Pass | State |
| 2025-03-10 | COBB STORAGE FIELD STATION 017 | Pass | State |
| 2025-03-10 | COBB STORAGE FIELD STATION 017 | Pass | State |
| 2025-03-10 | COBB STORAGE FIELD STATION 017 | Pass | State |
| 2025-03-10 | COBB STORAGE FIELD STATION 017 | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.