EPA Air · stack tests by state and year
Air-emissions stack tests in Wyoming, 2026
- 755Stack tests
A stack test measures what a source actually emits, at the stack, against the limit in its permit. Every stack test below was recorded against a source in Wyoming during 2026; one facility can appear more than once, because this is a record of what happened rather than a list of places.
Counties in Wyoming, 2026
- Campbell County 255
- Sweetwater County 129
- Sublette County 110
- Converse County 92
- Carbon County 58
- Johnson County 33
- Laramie County 19
- Lincoln County 18
- Albany County 17
- Uinta County 6
- Platte County 5
- Crook County 4
- Fremont County 4
- Big Horn County 4
Wyoming, other years
Air-emissions stack tests recorded in Wyoming, 2026
| Date | Facility | Where | Kind | Agency |
|---|---|---|---|---|
| 2026-05-14 | WESTVACO FACILITY (WE SODA WYOMING LP) | SWEETWATER COUNTY, Sweetwater, WY | Pass | State |
| 2026-05-14 | WESTVACO FACILITY (WE SODA WYOMING LP) | SWEETWATER COUNTY, Sweetwater, WY | Pass | State |
| 2026-05-13 | HF SINCLAIR PARCO REFINING LLC — high-priority violation on file | SINCLAIR, Carbon, WY | Pass | State |
| 2026-05-13 | HF SINCLAIR PARCO REFINING LLC — high-priority violation on file | SINCLAIR, Carbon, WY | Pass | State |
| 2026-05-11 | COLONY PLANT (BENTONITE PERFORMANCE MINERALS) | COLONY, Crook, WY | Pass | State |
| 2026-05-11 | WESTVACO FACILITY (WE SODA WYOMING LP) | SWEETWATER COUNTY, Sweetwater, WY | Pass | State |
| 2026-05-11 | WESTVACO FACILITY (WE SODA WYOMING LP) | SWEETWATER COUNTY, Sweetwater, WY | Pass | State |
| 2026-05-08 | HOUSE CREEK MAINLINE COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-08 | HOUSE CREEK MAINLINE COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-08 | HOUSE CREEK MAINLINE COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-08 | HOUSE CREEK MAINLINE COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-08 | HOUSE CREEK MAINLINE COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-08 | HOUSE CREEK MAINLINE COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-08 | HOUSE CREEK MAINLINE COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-08 | HOUSE CREEK MAINLINE COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | HILIGHT GAS PLANT (WES POWDER RIVER HOLDINGS LLC) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | HILIGHT GAS PLANT (WES POWDER RIVER HOLDINGS LLC) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | HILIGHT GAS PLANT (WES POWDER RIVER HOLDINGS LLC) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | HILIGHT GAS PLANT (WES POWDER RIVER HOLDINGS LLC) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | HILIGHT GAS PLANT (WES POWDER RIVER HOLDINGS LLC) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | HILIGHT GAS PLANT (WES POWDER RIVER HOLDINGS LLC) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | LEAVITT COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | LEAVITT COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | LEAVITT COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | LEAVITT COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | ANTELOPE HILLS COMPRESSOR STATION (EOG RESOURCES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | ANTELOPE HILLS COMPRESSOR STATION (EOG RESOURCES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | ANTELOPE HILLS COMPRESSOR STATION (EOG RESOURCES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | ANTELOPE HILLS COMPRESSOR STATION (EOG RESOURCES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | ANTELOPE HILLS COMPRESSOR STATION (EOG RESOURCES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | ANTELOPE HILLS COMPRESSOR STATION (EOG RESOURCES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | ANTELOPE HILLS COMPRESSOR STATION (EOG RESOURCES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | ANTELOPE HILLS COMPRESSOR STATION (EOG RESOURCES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | ANTELOPE HILLS COMPRESSOR STATION (EOG RESOURCES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | ANTELOPE HILLS COMPRESSOR STATION (EOG RESOURCES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | ANTELOPE HILLS COMPRESSOR STATION (EOG RESOURCES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-07 | ANTELOPE HILLS COMPRESSOR STATION (EOG RESOURCES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-05-05 | WYODAK PLANT (PACIFICORP) | GILLETTE, Campbell, WY | Pass | State |
| 2026-05-05 | NEIL SIMPSON COMPLEX (BLACK HILLS CORPORATION) | GILLETTE, Campbell, WY | Pass | State |
| 2026-05-05 | NEIL SIMPSON COMPLEX (BLACK HILLS CORPORATION) | GILLETTE, Campbell, WY | Pass | State |
| 2026-05-05 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-05-05 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-05-05 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-05-05 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-05-05 | WESTVACO FACILITY (WE SODA WYOMING LP) | SWEETWATER COUNTY, Sweetwater, WY | Pass | State |
| 2026-04-30 | DAVE JOHNSTON (PACIFICORP) | GLENROCK, Converse, WY | Pass | State |
| 2026-04-29 | DAVE JOHNSTON (PACIFICORP) | GLENROCK, Converse, WY | Pass | State |
| 2026-04-29 | DAVE JOHNSTON (PACIFICORP) | GLENROCK, Converse, WY | Pass | State |
| 2026-04-24 | BAGGS MAINLINE/BLUE GAP COMPRESSOR STATION (CROWHEART ENERGY, LLC) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-04-24 | BAGGS MAINLINE/BLUE GAP COMPRESSOR STATION (CROWHEART ENERGY, LLC) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-04-24 | BAGGS MAINLINE/BLUE GAP COMPRESSOR STATION (CROWHEART ENERGY, LLC) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-04-24 | BAGGS MAINLINE/BLUE GAP COMPRESSOR STATION (CROWHEART ENERGY, LLC) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-04-23 | NAUGHTON PLANT (PACIFICORP) | KEMMERER, Lincoln, WY | Pass | State |
| 2026-04-22 | MORGAN DRAW/CRENSHAW HILL (PRONGHORN MIDSTREAM LLC) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-04-22 | MORGAN DRAW/CRENSHAW HILL (PRONGHORN MIDSTREAM LLC) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-04-22 | MORGAN DRAW/CRENSHAW HILL (PRONGHORN MIDSTREAM LLC) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-04-21 | JONATHON LIME PLANT & LIME KILN DUST LANDFILL (PETE LIEN & SONS INC) | ALBANY COUNTY, Albany, WY | Pass | State |
| 2026-04-21 | JONATHON LIME PLANT & LIME KILN DUST LANDFILL (PETE LIEN & SONS INC) | ALBANY COUNTY, Albany, WY | Pass | State |
| 2026-04-21 | JONATHON LIME PLANT & LIME KILN DUST LANDFILL (PETE LIEN & SONS INC) | ALBANY COUNTY, Albany, WY | Pass | State |
| 2026-04-21 | JONATHON LIME PLANT & LIME KILN DUST LANDFILL (PETE LIEN & SONS INC) | ALBANY COUNTY, Albany, WY | Pass | State |
| 2026-04-21 | JONATHON LIME PLANT & LIME KILN DUST LANDFILL (PETE LIEN & SONS INC) | ALBANY COUNTY, Albany, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-16 | DOUGLAS GAS PLANT (TALLGRASS MIDSTREAM) | DOUGLAS, Converse, WY | Pass | State |
| 2026-04-10 | BUCKING HORSE PLANT (JACKALOPE GAS GATHERING) | CONVERSE COUNTY, Converse, WY | Pass | State |
| 2026-04-10 | BUCKING HORSE PLANT (JACKALOPE GAS GATHERING) | CONVERSE COUNTY, Converse, WY | Pass | State |
| 2026-04-10 | BUCKING HORSE PLANT (JACKALOPE GAS GATHERING) | CONVERSE COUNTY, Converse, WY | Pass | State |
| 2026-04-10 | BUCKING HORSE PLANT (JACKALOPE GAS GATHERING) | CONVERSE COUNTY, Converse, WY | Pass | State |
| 2026-04-10 | AUGUSTA-PEBBLE BEACH COMPRESSOR STATION (PRONGHORN MIDSTREAM LLC) | JOHNSON COUNTY, Johnson, WY | Pass | State |
| 2026-04-10 | AUGUSTA-PEBBLE BEACH COMPRESSOR STATION (PRONGHORN MIDSTREAM LLC) | JOHNSON COUNTY, Johnson, WY | Pass | State |
| 2026-04-10 | AUGUSTA-PEBBLE BEACH COMPRESSOR STATION (PRONGHORN MIDSTREAM LLC) | JOHNSON COUNTY, Johnson, WY | Pass | State |
| 2026-04-10 | AUGUSTA-PEBBLE BEACH COMPRESSOR STATION (PRONGHORN MIDSTREAM LLC) | JOHNSON COUNTY, Johnson, WY | Pass | State |
| 2026-04-10 | AUGUSTA-PEBBLE BEACH COMPRESSOR STATION (PRONGHORN MIDSTREAM LLC) | JOHNSON COUNTY, Johnson, WY | Pass | State |
| 2026-04-10 | AUGUSTA-PEBBLE BEACH COMPRESSOR STATION (PRONGHORN MIDSTREAM LLC) | JOHNSON COUNTY, Johnson, WY | Pass | State |
| 2026-04-09 | CHEYENNE PRAIRIE GENERATING STATION (CHEYENNE LIGHT FUEL & POWER) | CHEYENNE, Laramie, WY | Pass | State |
| 2026-04-09 | CHEYENNE PRAIRIE GENERATING STATION (CHEYENNE LIGHT FUEL & POWER) | CHEYENNE, Laramie, WY | Pass | State |
| 2026-04-09 | CHEYENNE PRAIRIE GENERATING STATION (CHEYENNE LIGHT FUEL & POWER) | CHEYENNE, Laramie, WY | Pass | State |
| 2026-04-08 | STEAMBOAT PROCESSING FACILITY (THUNDER CREEK GAS SERVICES) | CONVERSE COUNTY, Converse, WY | Pass | State |
| 2026-04-08 | STEAMBOAT PROCESSING FACILITY (THUNDER CREEK GAS SERVICES) | CONVERSE COUNTY, Converse, WY | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.