EPA Air · stack tests by year
Air-emissions stack tests in 2026
- 11,110Stack tests
A stack test measures what a source actually emits, at the stack, against the limit in its permit.
States, 2026
- Ohio 1,474
- Indiana 1,010
- California 979
- Florida 795
- Wyoming 755
- New Mexico 724
- Georgia 509
- Pennsylvania 501
- Arkansas 374
- Alabama 357
- Missouri 326
- Texas 316
- Mississippi 263
- Michigan 207
- North Carolina 188
- Colorado 185
- Iowa 167
- Illinois 165
- South Carolina 135
- Wisconsin 135
- West Virginia 114
- Virginia 98
- Idaho 96
- Montana 91
- Tennessee 84
- Minnesota 84
- Delaware 73
- Kentucky 71
- Arizona 71
- Connecticut 68
- Kansas 63
- Nevada 57
- Massachusetts 54
- North Dakota 52
- Nebraska 51
- Utah 51
- Washington 46
- Alaska 45
- New York 43
- South Dakota 34
- District of Columbia 30
- New Hampshire 29
- Maryland 28
- Oregon 27
- Louisiana 26
- Hawaii 21
- Oklahoma 15
- Rhode Island 13
- Puerto Rico 5
- Maine 5
Other years
Air-emissions stack tests recorded in 2026
| Date | Facility | Where | Kind | Agency |
|---|---|---|---|---|
| 2026-07-21 | WE ENERGIES-OAK CREEK POWER PLANT — high-priority violation on file | OAK CREEK, Monroe, WI | Pass | State |
| 2026-07-21 | OPAL GAS PLANT (WILLIAMS FIELD SERVICES) | OPAL, Lincoln, WY | Pass | State |
| 2026-07-21 | OPAL GAS PLANT (WILLIAMS FIELD SERVICES) | OPAL, Lincoln, WY | Pass | State |
| 2026-07-21 | OPAL GAS PLANT (WILLIAMS FIELD SERVICES) | OPAL, Lincoln, WY | Pass | State |
| 2026-07-20 | TARGA BADLANDS JUNCTION COMPRESSOR STATION | MCKENZIE COUNTY, McKenzie, ND | Pass | U.S. EPA |
| 2026-07-20 | TARGA BADLANDS JUNCTION COMPRESSOR STATION | MCKENZIE COUNTY, McKenzie, ND | Pass | U.S. EPA |
| 2026-07-20 | TARGA BADLANDS JUNCTION COMPRESSOR STATION | MCKENZIE COUNTY, McKenzie, ND | Pass | U.S. EPA |
| 2026-07-20 | BLUE BUTTES COMPRESSOR STATION AND PUMP STATION | MCKENZIE COUNTY, McKenzie, ND | Pass | U.S. EPA |
| 2026-07-20 | BLUE BUTTES COMPRESSOR STATION AND PUMP STATION | MCKENZIE COUNTY, McKenzie, ND | Pass | U.S. EPA |
| 2026-07-20 | BLUE BUTTES COMPRESSOR STATION AND PUMP STATION | MCKENZIE COUNTY, McKenzie, ND | Pass | U.S. EPA |
| 2026-07-20 | TAT-BLUE BUTTES COMPRESSOR STATION | MCKENZIE COUNTY, McKenzie, ND | Pass | U.S. EPA |
| 2026-07-20 | TAT-BLUE BUTTES COMPRESSOR STATION | MCKENZIE COUNTY, McKenzie, ND | Pass | U.S. EPA |
| 2026-07-20 | TAT-BLUE BUTTES COMPRESSOR STATION | MCKENZIE COUNTY, McKenzie, ND | Pass | U.S. EPA |
| 2026-07-20 | TAT-BLUE BUTTES COMPRESSOR STATION | MCKENZIE COUNTY, McKenzie, ND | Pass | U.S. EPA |
| 2026-07-20 | TAT-BLUE BUTTES COMPRESSOR STATION | MCKENZIE COUNTY, McKenzie, ND | Pass | U.S. EPA |
| 2026-07-20 | CALUMET MONTANA REFINING — high-priority violation on file | GREAT FALLS, Cascade, MT | Pass | State |
| 2026-07-20 | CALUMET MONTANA REFINING — high-priority violation on file | GREAT FALLS, Cascade, MT | Pass | State |
| 2026-07-20 | CALUMET MONTANA REFINING — high-priority violation on file | GREAT FALLS, Cascade, MT | Pass | State |
| 2026-07-20 | APC, INC. - SELMA | SELMA, Johnston, NC | Pending | State |
| 2026-07-20 | NPPD SHELDON STATION | HALLAM, Lancaster, NE | Pass | Local |
| 2026-07-20 | CABOT OIL & GAS CORP/JEFFERS FARMS PAD 5 | GIBSON, Susquehanna, PA | Pending | State |
| 2026-07-20 | CABOT OIL & GAS CORP/FOLTZ J PAD 1 | HOP BOTTOM, Susquehanna, PA | Pass | State |
| 2026-07-20 | REEVES CONSTRUCTION COMPANY - BLACKSBURG ASPHALT PLANT | BLACKSBURG, Cherokee, SC | Pass | State |
| 2026-07-19 | HILLTOP ENERGY CENTER LLC/CARMICHAELS | CARMICHAELS, Greene, PA | Pass | State |
| 2026-07-17 | LENZING FIBERS INC | AXIS, Mobile, AL | Pass | State |
| 2026-07-17 | LENZING FIBERS INC | AXIS, Mobile, AL | Pass | State |
| 2026-07-17 | AM/NS CALVERT LLC | CALVERT, Mobile, AL | Pass | State |
| 2026-07-17 | ITW GRAPHICS | MANCHESTER, Hartford, CT | Pending | State |
| 2026-07-17 | DUKE ENERGY FLORIDA, LLC | INTERCESSION CITY, Osceola, FL | Pass | State |
| 2026-07-17 | DUKE ENERGY FLORIDA, LLC | INTERCESSION CITY, Osceola, FL | Pass | State |
| 2026-07-17 | HK CONTRACTORS INC 00079 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-07-17 | HK CONTRACTORS INC 00121 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-07-17 | HK CONTRACTORS INC 00168 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-07-17 | HK CONTRACTORS 00413 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-07-17 | HK CONTRACTORS INC 00463 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-07-17 | HK CONTRACTORS INC 00480 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-07-17 | HK CONTRACTORS 00495 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-07-17 | BUTTERFIELD ROAD CCDD | NORTH AURORA, Kane, IL | Pass | State |
| 2026-07-17 | WABASH STEEL COMPANY LLC — high-priority violation on file | VINCENNES, Knox, IN | Pass | State |
| 2026-07-17 | WABASH STEEL COMPANY LLC — high-priority violation on file | VINCENNES, Knox, IN | Pass | State |
| 2026-07-17 | WABASH STEEL COMPANY LLC — high-priority violation on file | VINCENNES, Knox, IN | Pass | State |
| 2026-07-17 | WABASH STEEL COMPANY LLC — high-priority violation on file | VINCENNES, Knox, IN | Pass | State |
| 2026-07-17 | NUCOR STEEL LEXINGTON | LEXINGTON, Davidson, NC | Pending | State |
| 2026-07-17 | EOG RESOURCES, INC - INDIGO CTB | MALVERN, Carroll, OH | Pass | State |
| 2026-07-17 | EOG RESOURCES, INC - INDIGO CTB | MALVERN, Carroll, OH | Pass | State |
| 2026-07-17 | EOG RESOURCES, INC - INDIGO CTB | MALVERN, Carroll, OH | Pass | State |
| 2026-07-17 | PRECISION CAPITAL, LP PAD 1 | HOP BOTTOM, Susquehanna, PA | Pass | State |
| 2026-07-17 | US ARMY - RAAP — high-priority violation on file | RADFORD, Montgomery, VA | Pending | State |
| 2026-07-17 | ENVIVA SOUTHAMPTON | FRANKLIN, Southampton, VA | Pending | State |
| 2026-07-16 | ALABAMA POWER COMPANY (MILLER POWER PLANT) | QUINTON, Jefferson, AL | Pass | Local |
| 2026-07-16 | EMERY SAPP & SONS, INC. - GRAVETTE ASPHALT PLANT | SULPHUR SPRINGS, Benton, AR | Pass | State |
| 2026-07-16 | NRO - AEROSPACE DATA FACIITY (ADF-C) | AURORA, Arapahoe, CO | Pass | State |
| 2026-07-16 | ENTERPRISE GAS PROC - MEEKER GAS PLANT — high-priority violation on file | MEEKER 21.1 MI. W OF, Rio Blanco, CO | N/A | State |
| 2026-07-16 | GB II NEW HAVEN, LLC - NEW HAVEN HARBOR STATION | NEW HAVEN, New Haven, CT | Pending | State |
| 2026-07-16 | DUKE ENERGY FLORIDA, LLC | INTERCESSION CITY, Osceola, FL | Pass | State |
| 2026-07-16 | DUKE ENERGY FLORIDA, LLC | INTERCESSION CITY, Osceola, FL | Pass | State |
| 2026-07-16 | CLEARWATER PAPER CORP-PPD | LEWISTON, Nez Perce, ID | Pass | State |
| 2026-07-16 | SUNCORE CONSTRUCTION & MATERIALS 00552 | IDAHO FALLS, Bonneville, ID | Pending | State |
| 2026-07-16 | CARGILL INC — high-priority violation on file | HAMMOND, Lake, IN | Pass | State |
| 2026-07-16 | CARGILL INC — high-priority violation on file | HAMMOND, Lake, IN | Pass | State |
| 2026-07-16 | CARGILL INC — high-priority violation on file | HAMMOND, Lake, IN | Pass | State |
| 2026-07-16 | ARK VALLEY ELECTRIC CO-OP - ARLINGTON SUBSTATION (AIR) | ARLINGTON, Reno, KS | Pass | State |
| 2026-07-16 | DTE ELECTRIC COMPANY - MONROE POWER PLANT | MONROE, Monroe, MI | Pass | State |
| 2026-07-16 | CONSUMERS ENERGY - ST. CLAIR COMPRESSOR STATION | IRA, St. Clair, MI | Pass | State |
| 2026-07-16 | FSC II, LLC - KNIGHTDALE ASPHALT PLANT | KNIGHTDALE, Wake, NC | Pending | State |
| 2026-07-16 | NPPD SHELDON STATION | HALLAM, Lancaster, NE | Pass | Local |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | MARKWEST TRI-COUNTY COMPRESSOR STATION | BARNESVILLE, Belmont, OH | Pass | State |
| 2026-07-16 | EOG RESOURCES, INC. - E CLARK SOUTH CTB | TIPPECANOE, Harrison, OH | Pass | State |
| 2026-07-16 | EOG RESOURCES, INC. - E CLARK SOUTH CTB | TIPPECANOE, Harrison, OH | Pass | State |
| 2026-07-16 | EOG RESOURCES, INC. - E CLARK SOUTH CTB | TIPPECANOE, Harrison, OH | Pass | State |
| 2026-07-16 | EOG RESOURCES, INC. - BEARCATS NB BUF PAD | BUFFALO, TOWNSHIP OF, Noble, OH | Pass | State |
| 2026-07-16 | EOG RESOURCES, INC. - BEARCATS NB BUF PAD | BUFFALO, TOWNSHIP OF, Noble, OH | Pass | State |
| 2026-07-16 | EOG RESOURCES, INC. - BEARCATS NB BUF PAD | BUFFALO, TOWNSHIP OF, Noble, OH | Pass | State |
| 2026-07-16 | SOUTHERLY WASTEWATER TREATMENT CENTER | CUYAHOGA HEIGHTS, Cuyahoga, OH | Pass | State |
| 2026-07-16 | SOUTHERLY WASTEWATER TREATMENT CENTER | CUYAHOGA HEIGHTS, Cuyahoga, OH | Pass | State |
| 2026-07-16 | SOUTHERLY WASTEWATER TREATMENT CENTER | CUYAHOGA HEIGHTS, Cuyahoga, OH | Pass | State |
| 2026-07-16 | SOUTHERLY WASTEWATER TREATMENT CENTER | CUYAHOGA HEIGHTS, Cuyahoga, OH | Pass | State |
| 2026-07-16 | SOUTHERLY WASTEWATER TREATMENT CENTER | CUYAHOGA HEIGHTS, Cuyahoga, OH | Pass | State |
| 2026-07-16 | ENVIRONMENTAL AND MAINTENANCE SERVICE CENTER (EMSC) | CUYAHOGA HEIGHTS, Cuyahoga, OH | Pass | State |
| 2026-07-16 | NORTHUMBERLAND TERM DE LLC/NORTHUMBERLAND TERM | NORTHUMBERLAND, Northumberland, PA | Pass | State |
| 2026-07-16 | SUSQUEHANNA GATHERING/CDP 1 COMP STA | NEW MILFORD, Susquehanna, PA | Pass | State |
| 2026-07-16 | CABOT OIL & GAS CORP/TEDDICK, M. PAD 1 | KINGSLEY, Susquehanna, PA | Pass | State |
| 2026-07-16 | A M WILLIAMS STATION | GOOSE CREEK, Berkeley, SC | Pending | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.