EPA Air · stack tests by state and year
Air-emissions stack tests in Montana, 2021
- 220Stack 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 Montana during 2021; one facility can appear more than once, because this is a record of what happened rather than a list of places.
Counties in Montana, 2021
- Yellowstone County 67
- Glacier County 20
- Rosebud County 18
- Fallon County 12
- Cascade County 11
- Jefferson County 9
- Silver Bow County 9
- Flathead County 8
- Big Horn County 8
- Phillips County 8
- Gallatin County 7
- Blaine County 6
- Lewis and Clark County 6
- Deer Lodge County 6
- Richland County 6
- Valley County 5
- Stillwater County 4
- Dawson County 3
Montana, other years
Air-emissions stack tests recorded in Montana, 2021
| Date | Facility | Where | Kind | Agency |
|---|---|---|---|---|
| 2021-07-07 | CHS INC REFINERY LAUREL | LAUREL, Yellowstone, MT | Pass | State |
| 2021-07-07 | CHS INC REFINERY LAUREL | LAUREL, Yellowstone, MT | Pass | State |
| 2021-07-07 | CHS INC REFINERY LAUREL | LAUREL, Yellowstone, MT | Pass | State |
| 2021-07-06 | GRAYMONT WESTERN US INC | TOWNSEND, Broadwater, MT | Pass | State |
| 2021-07-01 | ROCKY MOUNTAIN POWER | HARDIN, Big Horn, MT | Pass | State |
| 2021-06-29 | ASH GROVE CEMENT | CLANCY, Jefferson, MT | Pass | State |
| 2021-06-29 | ASH GROVE CEMENT | CLANCY, Jefferson, MT | Pass | State |
| 2021-06-29 | ASH GROVE CEMENT | CLANCY, Jefferson, MT | Pass | State |
| 2021-06-29 | ASH GROVE CEMENT | CLANCY, Jefferson, MT | Pass | State |
| 2021-06-29 | ASH GROVE CEMENT | CLANCY, Jefferson, MT | Pass | State |
| 2021-06-29 | ROCKY MOUNTAIN LABORATORIES FACILITY | HAMILTON, Ravalli, MT | Pass | State |
| 2021-06-21 | PRAIRIE DELL CASCADE GAS PLANT | SHELBY, Toole, MT | Pass | State |
| 2021-06-11 | WILLISTON BASIN - HATHAWAY STATION | HATHAWAY, Rosebud, MT | Pass | State |
| 2021-06-11 | WILLISTON BASIN - HATHAWAY STATION | HATHAWAY, Rosebud, MT | Pass | State |
| 2021-06-11 | WILLISTON BASIN - FORT PECK STATION | NASHUA, Valley, MT | Pass | State |
| 2021-06-11 | WILLISTON BASIN - FORT PECK STATION | NASHUA, Valley, MT | Pass | State |
| 2021-06-04 | PAR MONTANA BILLINGS REFINERY | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-06-04 | PAR MONTANA BILLINGS REFINERY | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-06-04 | PAR MONTANA BILLINGS REFINERY | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-05-27 | COLSTRIP STEAM ELECTRIC STATION | COLSTRIP, Rosebud, MT | Pass | State |
| 2021-05-27 | COLSTRIP STEAM ELECTRIC STATION | COLSTRIP, Rosebud, MT | Pass | State |
| 2021-05-25 | BILLINGS REFINERY | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-05-12 | MDU - LEWIS & CLARK STATION | SIDNEY, Richland, MT | Pass | State |
| 2021-05-12 | MDU - LEWIS & CLARK STATION | SIDNEY, Richland, MT | Pass | State |
| 2021-05-06 | WILLISTON BASIN - SACO | SACO, Phillips, MT | Pass | State |
| 2021-05-06 | WILLISTON BASIN - SACO | SACO, Phillips, MT | Pass | State |
| 2021-05-06 | WILLISTON BASIN - SACO | SACO, Phillips, MT | Pass | State |
| 2021-05-06 | WILLISTON BASIN - SACO | SACO, Phillips, MT | Pass | State |
| 2021-05-05 | YELLOWSTONE POWER PLANT — high-priority violation on file | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-05-03 | YELLOWSTONE POWER PLANT — high-priority violation on file | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-04-27 | MDU - LEWIS & CLARK STATION | SIDNEY, Richland, MT | Pass | State |
| 2021-04-19 | ROCKY MOUNTAIN POWER | HARDIN, Big Horn, MT | Pass | State |
| 2021-04-19 | CHS INC REFINERY LAUREL | LAUREL, Yellowstone, MT | Pass | State |
| 2021-04-19 | CHS INC REFINERY LAUREL | LAUREL, Yellowstone, MT | Pass | State |
| 2021-04-19 | CHS INC REFINERY LAUREL | LAUREL, Yellowstone, MT | Pass | State |
| 2021-04-19 | CHS INC REFINERY LAUREL | LAUREL, Yellowstone, MT | Pass | State |
| 2021-04-16 | WILLISTON BASIN - CABIN CREEK | BAKER, Fallon, MT | Pass | State |
| 2021-04-16 | WILLISTON BASIN - CABIN CREEK | BAKER, Fallon, MT | Pass | State |
| 2021-04-16 | WILLISTON BASIN - CABIN CREEK | BAKER, Fallon, MT | Pass | State |
| 2021-04-16 | BOZEMAN PRODUCT TERMINAL | BOZEMAN, Gallatin, MT | Pass | State |
| 2021-04-07 | MSU - CENTRAL HEATING PLANT | BOZEMAN, Gallatin, MT | Pass | State |
| 2021-04-06 | WILLISTON BASIN - LITTLE BEAVER | BAKER, Fallon, MT | Pass | State |
| 2021-04-06 | WILLISTON BASIN - CABIN CREEK | BAKER, Fallon, MT | Pass | State |
| 2021-04-06 | WILLISTON BASIN - CABIN CREEK | BAKER, Fallon, MT | Pass | State |
| 2021-04-02 | WILLISTON BASIN - CABIN CREEK | BAKER, Fallon, MT | Pass | State |
| 2021-03-19 | COBB STORAGE FIELD STATION 017 | CUT BANK, Glacier, MT | Pass | State |
| 2021-03-19 | COBB STORAGE FIELD STATION 017 | CUT BANK, Glacier, MT | Pass | State |
| 2021-03-19 | COBB STORAGE FIELD STATION 017 | CUT BANK, Glacier, MT | Pass | State |
| 2021-03-19 | COBB STORAGE FIELD STATION 017 | CUT BANK, Glacier, MT | Pass | State |
| 2021-03-19 | COBB STORAGE FIELD STATION 017 | CUT BANK, Glacier, MT | Pass | State |
| 2021-03-19 | COBB STORAGE FIELD STATION 017 | CUT BANK, Glacier, MT | Pass | State |
| 2021-03-19 | COBB STORAGE FIELD STATION 017 | CUT BANK, Glacier, MT | Pass | State |
| 2021-03-19 | COBB STORAGE FIELD STATION 017 | CUT BANK, Glacier, MT | Pass | State |
| 2021-03-19 | COLSTRIP STEAM ELECTRIC STATION | COLSTRIP, Rosebud, MT | Pass | State |
| 2021-03-19 | COLSTRIP STEAM ELECTRIC STATION | COLSTRIP, Rosebud, MT | Pass | State |
| 2021-03-18 | COLSTRIP STEAM ELECTRIC STATION | COLSTRIP, Rosebud, MT | Pass | State |
| 2021-03-18 | COLSTRIP STEAM ELECTRIC STATION | COLSTRIP, Rosebud, MT | Pass | State |
| 2021-03-15 | STILLWATER MINING CO SMELTER | COLUMBUS, Stillwater, MT | Pass | State |
| 2021-03-12 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2021-03-12 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2021-03-12 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2021-03-12 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2021-03-12 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2021-03-12 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2021-03-12 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2021-03-12 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2021-03-12 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2021-03-05 | COLSTRIP STEAM ELECTRIC STATION | COLSTRIP, Rosebud, MT | Pass | State |
| 2021-03-05 | COLSTRIP STEAM ELECTRIC STATION | COLSTRIP, Rosebud, MT | Pass | State |
| 2021-03-01 | BILLINGS REFINERY | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-02-25 | CHS INC. | GLENDIVE, Dawson, MT | Pass | State |
| 2021-02-22 | NORTHWESTERN ENERGY MAINLINE #1 | CUT BANK, Glacier, MT | Pass | State |
| 2021-02-22 | NORTHWESTERN ENERGY MAINLINE #1 | CUT BANK, Glacier, MT | Pass | State |
| 2021-02-22 | NORTHWESTERN ENERGY MAINLINE #1 | CUT BANK, Glacier, MT | Pass | State |
| 2021-02-22 | NORTHWESTERN ENERGY MAINLINE #1 | CUT BANK, Glacier, MT | Pass | State |
| 2021-02-22 | NORTHWESTERN ENERGY MAINLINE #1 | CUT BANK, Glacier, MT | Pass | State |
| 2021-02-22 | NORTHWESTERN ENERGY MAINLINE #1 | CUT BANK, Glacier, MT | Pass | State |
| 2021-02-18 | CALUMET MONTANA REFINING — high-priority violation on file | GREAT FALLS, Cascade, MT | Pass | State |
| 2021-02-18 | CALUMET MONTANA REFINING — high-priority violation on file | GREAT FALLS, Cascade, MT | Pass | State |
| 2021-02-18 | CALUMET MONTANA REFINING — high-priority violation on file | GREAT FALLS, Cascade, MT | Pass | State |
| 2021-02-18 | CALUMET MONTANA REFINING — high-priority violation on file | GREAT FALLS, Cascade, MT | Pass | State |
| 2021-02-11 | CALUMET MONTANA REFINING — high-priority violation on file | GREAT FALLS, Cascade, MT | Pass | State |
| 2021-02-05 | TRIDENT | THREE FORKS, Gallatin, MT | Pass | State |
| 2021-02-02 | BILLINGS REFINERY | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-02-02 | BILLINGS REFINERY | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-01-29 | COLSTRIP STEAM ELECTRIC STATION | COLSTRIP, Rosebud, MT | Pass | State |
| 2021-01-29 | COLSTRIP STEAM ELECTRIC STATION | COLSTRIP, Rosebud, MT | Pass | State |
| 2021-01-28 | COLSTRIP ENERGY LTD PARTNERSHIP | COLSTRIP, Rosebud, MT | Pass | State |
| 2021-01-23 | WILLISTON BASIN - LITTLE BEAVER | BAKER, Fallon, MT | Pass | State |
| 2021-01-22 | AUGUSTA MAIN LINE #3 (STA 051) | AUGUSTA, Lewis and Clark, MT | Pass | State |
| 2021-01-22 | AUGUSTA MAIN LINE #3 (STA 051) | AUGUSTA, Lewis and Clark, MT | Pass | State |
| 2021-01-22 | AUGUSTA MAIN LINE #3 (STA 051) | AUGUSTA, Lewis and Clark, MT | Pass | State |
| 2021-01-22 | AUGUSTA MAIN LINE #3 (STA 051) | AUGUSTA, Lewis and Clark, MT | Pass | State |
| 2021-01-21 | ROCKY MOUNTAIN POWER | HARDIN, Big Horn, MT | Pass | State |
| 2021-01-18 | BILLINGS REFINERY | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-01-15 | WESTERN SUGAR COOPERATIVE — high-priority violation on file | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-01-15 | MONTANA SULPHUR & CHEMICAL | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-01-14 | WESTERN SUGAR COOPERATIVE — high-priority violation on file | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-01-14 | WESTERN SUGAR COOPERATIVE — high-priority violation on file | BILLINGS, Yellowstone, MT | Pass | State |
| 2021-01-14 | WESTERN SUGAR COOPERATIVE — high-priority violation on file | BILLINGS, Yellowstone, MT | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.