EPA Air · stack tests by county and year
Air-emissions stack tests in Big Horn County, Wyoming, 2026
- 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 Big Horn County, Wyoming during 2026. 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 Big Horn County facility page.
Air-emissions stack tests in Big Horn County, other years
Air-emissions stack tests recorded in Big Horn County, Wyoming, 2026
| Date | Facility | Kind | Agency |
|---|---|---|---|
| 2026-03-05 | GREYBULL PLANT (WYO-BEN, INC.) | Pass | State |
| 2026-03-05 | GREYBULL PLANT (WYO-BEN, INC.) | Pass | State |
| 2026-03-05 | GREYBULL PLANT (WYO-BEN, INC.) | Pass | State |
| 2026-03-05 | GREYBULL PLANT (WYO-BEN, INC.) | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.