EPA Air · stack tests by county and year
Air-emissions stack tests in Stillwater County, Montana, 2021
- 4Stack 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 Stillwater County, Montana during 2021. 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 Stillwater County facility page.
Air-emissions stack tests in Stillwater County, other years
Air-emissions stack tests recorded in Stillwater County, Montana, 2021
| Date | Facility | Kind | Agency |
|---|---|---|---|
| 2021-10-28 | STILLWATER MINING CO SMELTER | Pass | State |
| 2021-09-13 | STILLWATER MINE | Pass | State |
| 2021-09-13 | STILLWATER MINE | Pass | State |
| 2021-03-15 | STILLWATER MINING CO SMELTER | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.