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 |
|---|---|---|---|---|
| 2026-04-30 | OHIO RIVER SYSTEM LLC - REX BOOSTER STATION | SWITZERLAND, TOWNSHIP OF, Monroe, OH | Pass | State |
| 2026-04-30 | OHIO RIVER SYSTEM LLC - REX BOOSTER STATION | SWITZERLAND, TOWNSHIP OF, Monroe, OH | Pass | State |
| 2026-04-30 | OHIO RIVER SYSTEM LLC - REX BOOSTER STATION | SWITZERLAND, TOWNSHIP OF, Monroe, OH | Pass | State |
| 2026-04-30 | OHIO RIVER SYSTEM LLC - REX BOOSTER STATION | SWITZERLAND, TOWNSHIP OF, Monroe, OH | Pass | State |
| 2026-04-30 | OHIO RIVER SYSTEM LLC - REX BOOSTER STATION | SWITZERLAND, TOWNSHIP OF, Monroe, OH | Pass | State |
| 2026-04-30 | OHIO RIVER SYSTEM LLC - REX BOOSTER STATION | SWITZERLAND, TOWNSHIP OF, Monroe, OH | Pass | State |
| 2026-04-30 | OHIO RIVER SYSTEM LLC - REX BOOSTER STATION | SWITZERLAND, TOWNSHIP OF, Monroe, OH | Pass | State |
| 2026-04-30 | OHIO RIVER SYSTEM LLC - REX BOOSTER STATION | SWITZERLAND, TOWNSHIP OF, Monroe, OH | Pass | State |
| 2026-04-30 | OHIO RIVER SYSTEM LLC - REX BOOSTER STATION | SWITZERLAND, TOWNSHIP OF, Monroe, OH | Pass | State |
| 2026-04-30 | OHIO RIVER SYSTEM LLC - REX BOOSTER STATION | SWITZERLAND, TOWNSHIP OF, Monroe, OH | Pass | State |
| 2026-04-30 | EOG RESOURCES, INC - OSPREY CTB | CALDWELL, Noble, OH | Pass | State |
| 2026-04-30 | EOG RESOURCES, INC - OSPREY CTB | CALDWELL, Noble, OH | Pass | State |
| 2026-04-30 | EOG RESOURCES, INC - OSPREY CTB | CALDWELL, Noble, OH | Pass | State |
| 2026-04-30 | GE AEROSPACE EVENDALE PLANT | CINCINNATI, Hamilton, OH | Pass | State |
| 2026-04-30 | GENERAL ALUMINUM | ROOTSTOWN, Portage, OH | Pass | State |
| 2026-04-30 | GRAYMONT PA INC/PLEASANT GAP & CON-LIME & BELLEFONTE PLTS | BELLEFONTE, Centre, PA | Pass | State |
| 2026-04-30 | EASTERN GAS TRANS & STORAGE/RURAL VLY COMP STA | KITTANNING, Armstrong, PA | Pass | State |
| 2026-04-30 | DIVERSIFIED PROD MARCHAND COMP STA | INDIANA, Indiana, PA | Pass | State |
| 2026-04-30 | PENNEX ALUM CO/GREENVILLE PLT | GREENVILLE, Mercer, PA | Pass | State |
| 2026-04-30 | CAREY, R. PAD 1 | KINGSLEY, Susquehanna, PA | Pass | State |
| 2026-04-30 | IKO GLASS FIBER INC - CHESTER PLANT | CHESTER, Chester, SC | Pending | State |
| 2026-04-30 | RESONAC GRAPHITE AMERICA INC — high-priority violation on file | RIDGEVILLE, Dorchester, SC | Pass | State |
| 2026-04-30 | CRUCIBLE ZINC, LLC — high-priority violation on file | CLARKSVILLE, Montgomery, TN | Pass | State |
| 2026-04-30 | STEEL DYNAMICS SOUTHWEST | SINTON, San Patricio, TX | Pass | State |
| 2026-04-30 | EAST TENNESSEE NATURAL GAS LLC-STATION 3401 | MCCLURE, Dickenson, VA | Pass | State |
| 2026-04-30 | ALIGNED DATA CENTERS IAD03 | STERLING, Loudoun, VA | Pending | State |
| 2026-04-30 | HRSD - VIRGINIA INITIATIVE WASTEWATER TREATMENT PLANT | NORFOLK, Norfolk (city), VA | Pass | State |
| 2026-04-30 | DAVE JOHNSTON (PACIFICORP) | GLENROCK, Converse, WY | Pass | State |
| 2026-04-29 | HILCORP ALASKA, LLC / STEELHEAD PLATFORM | KENAI, Kenai Peninsula, AK | Pass | State |
| 2026-04-29 | TECK ALASKA, INC. (TECK) / RED DOG MINE — high-priority violation on file | KOTZEBUE, Northwest Arctic, AK | Pending | State |
| 2026-04-29 | TECK ALASKA, INC. (TECK) / RED DOG MINE — high-priority violation on file | KOTZEBUE, Northwest Arctic, AK | N/A | State |
| 2026-04-29 | TECK ALASKA, INC. (TECK) / RED DOG MINE — high-priority violation on file | KOTZEBUE, Northwest Arctic, AK | Pending | State |
| 2026-04-29 | TECK ALASKA, INC. (TECK) / DMTS PORT FACILITY — high-priority violation on file | KOTZEBUE, Northwest Arctic, AK | Pending | State |
| 2026-04-29 | TECK ALASKA, INC. (TECK) / DMTS PORT FACILITY — high-priority violation on file | KOTZEBUE, Northwest Arctic, AK | Pending | State |
| 2026-04-29 | TRANSCONTINENTAL GAS PIPE LINE COMPANY L | SWEET WATER, Marengo, AL | Pass | State |
| 2026-04-29 | SOUTHERN NATURAL GAS | REFORM, Pickens, AL | Pass | State |
| 2026-04-29 | KYKENKEE INC/KUTZ LLC | VANCE, Tuscaloosa, AL | Pass | State |
| 2026-04-29 | ET GATHERING & PROCESSING LLC. - BROWNSVILLE COMPRESSOR STATION | BOONEVILLE, Logan, AR | Pass | State |
| 2026-04-29 | ET GATHERING & PROCESSING LLC. - BROWNSVILLE COMPRESSOR STATION | BOONEVILLE, Logan, AR | Pass | State |
| 2026-04-29 | RK HALL, LLC. | DE QUEEN, Sevier, AR | Pass | State |
| 2026-04-29 | RK HALL, LLC. | DE QUEEN, Sevier, AR | Fail | State |
| 2026-04-29 | SO CAL GAS - BLYTHE | BLYTHE, Riverside, CA | Pass | Local |
| 2026-04-29 | SO CAL GAS - BLYTHE | BLYTHE, Riverside, CA | Pass | Local |
| 2026-04-29 | PUBLIC SERVICE CO - CHEROKEE PLT | COMMERCE CITY AREA, Adams, CO | Pass | State |
| 2026-04-29 | PLAINS END, LLC | ARVADA, Jefferson, CO | Pass | State |
| 2026-04-29 | MIDDLETOWN POWER LLC | MIDDLETOWN, Middlesex, CT | Pass | State |
| 2026-04-29 | WARREN F BEASLEY POWER STATION (DEMEC) | SMYRNA, Kent, DE | Pass | State |
| 2026-04-29 | WARREN F BEASLEY POWER STATION (DEMEC) | SMYRNA, Kent, DE | Pass | State |
| 2026-04-29 | WARREN F BEASLEY POWER STATION (DEMEC) | SMYRNA, Kent, DE | Pass | State |
| 2026-04-29 | WARREN F BEASLEY POWER STATION (DEMEC) | SMYRNA, Kent, DE | Pass | State |
| 2026-04-29 | NEXPERA, LLC - NEXPERA RED LION PLANT | NEW CASTLE, New Castle, DE | Pass | State |
| 2026-04-29 | NEXPERA, LLC - NEXPERA RED LION PLANT | NEW CASTLE, New Castle, DE | Pass | State |
| 2026-04-29 | NEXPERA, LLC - NEXPERA RED LION PLANT | NEW CASTLE, New Castle, DE | Fail | State |
| 2026-04-29 | SOLID WASTE AUTHORITY OF PBC | WEST PALM BEACH, Palm Beach, FL | Pass | State |
| 2026-04-29 | SOLID WASTE AUTHORITY OF PBC | WEST PALM BEACH, Palm Beach, FL | Pass | State |
| 2026-04-29 | SOLID WASTE AUTHORITY OF PBC | WEST PALM BEACH, Palm Beach, FL | Pass | State |
| 2026-04-29 | RM CLAYTON WATER RECLAMATION CENTER — high-priority violation on file | ATLANTA, Fulton, GA | Pass | State |
| 2026-04-29 | GA POWER CO. - PLANT SCHERER | JULIETTE, Monroe, GA | Pass | State |
| 2026-04-29 | GA POWER CO. - PLANT SCHERER | JULIETTE, Monroe, GA | Pass | State |
| 2026-04-29 | GA POWER CO. - PLANT SCHERER | JULIETTE, Monroe, GA | Pass | State |
| 2026-04-29 | UNIVERSITY OF IOWA | IOWA CITY, Johnson, IA | Pass | State |
| 2026-04-29 | MICROSOFT CORPORATION - WILLOW CREEK/GINGER EAST DATA | DES MOINES, Polk, IA | Pass | Local |
| 2026-04-29 | STIMSON LUMBER COMPANY PRIEST RIVER | PRIEST RIVER, Bonner, ID | Pass | State |
| 2026-04-29 | HK CONTRACTORS INC 00079 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-04-29 | HK CONTRACTORS INC 00121 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-04-29 | HK CONTRACTORS INC 00168 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-04-29 | HK CONTRACTORS 00413 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-04-29 | HK CONTRACTORS INC 00463 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-04-29 | HK CONTRACTORS INC 00480 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-04-29 | HK CONTRACTORS 00495 | IDAHO FALLS, Bonneville, ID | Pass | State |
| 2026-04-29 | ARCHER DANIELS MIDLAND CO — high-priority violation on file | DECATUR, Macon, IL | Fail | State |
| 2026-04-29 | STEEL DYNAMICS INCORPORATED ENGINEERED BAR PRODUCTS DIVISION — high-priority violation on file | PITTSBORO, Hendricks, IN | Pass | State |
| 2026-04-29 | STEEL DYNAMICS INCORPORATED ENGINEERED BAR PRODUCTS DIVISION — high-priority violation on file | PITTSBORO, Hendricks, IN | Pass | State |
| 2026-04-29 | STEEL DYNAMICS INCORPORATED ENGINEERED BAR PRODUCTS DIVISION — high-priority violation on file | PITTSBORO, Hendricks, IN | Pass | State |
| 2026-04-29 | TATE & LYLE SOLUTIONS USA LLC — high-priority violation on file | LAFAYETTE, Tippecanoe, IN | Pass | State |
| 2026-04-29 | UNITED STATES GYPSUM COMPANY | CURTIS BAY, Baltimore (city), MD | Pass | State |
| 2026-04-29 | MARTIN MARIETTA MAGNESIA SPECIALTIES, LLC | MANISTEE, Manistee, MI | Pass | State |
| 2026-04-29 | GRAPHIC PACKAGING INTERNATIONAL LLC | KALAMAZOO, Kalamazoo, MI | Pass | State |
| 2026-04-29 | DETROIT THERMAL BEACON HEATING PLANT | DETROIT, Wayne, MI | Pass | State |
| 2026-04-29 | KNAUF INSULATION, INC. | ALBION, Calhoun, MI | Pass | State |
| 2026-04-29 | DTE GAS COMPANY - WILLOW RUN COMPRESSOR STATION | YPSILANTI, Washtenaw, MI | Pass | State |
| 2026-04-29 | ADVANCED ARCHITECHURAL PRODUCTS | HAMILTON, Allegan, MI | Pass | State |
| 2026-04-29 | KINDER MORGAN | BUCHANAN, Berrien, MI | Pass | State |
| 2026-04-29 | AMRIZE MIDWEST INC - NONMETALLIC | EAGAN, Dakota, MN | Pass | State |
| 2026-04-29 | PERHAM RESOURCE RECOVERY FACILITY | PERHAM, Otter Tail, MN | Pass | State |
| 2026-04-29 | CALGON CARBON CORPORATION | BAY ST. LOUI, Hancock, MS | Pass | State |
| 2026-04-29 | CALGON CARBON CORPORATION | BAY ST. LOUI, Hancock, MS | Pass | State |
| 2026-04-29 | CHEVRON USA INC, CHEVRON PRODUCTS COMPANY, PASCAGOULA REFINERY | PASCAGOULA, Jackson, MS | Pass | State |
| 2026-04-29 | CHEVRON USA INC, CHEVRON PRODUCTS COMPANY, PASCAGOULA REFINERY | PASCAGOULA, Jackson, MS | Pass | State |
| 2026-04-29 | CHEVRON USA INC, CHEVRON PRODUCTS COMPANY, PASCAGOULA REFINERY | PASCAGOULA, Jackson, MS | Pass | State |
| 2026-04-29 | COOPERATIVE ENERGY, A MISSISSIPPI ELECTRIC COOPERATIVE, SYLVARENA GENERATING PLA — high-priority violation on file | BAY SPRINGS, Smith, MS | Pass | State |
| 2026-04-29 | NC DOA CENTRAL HEATING PLANT | RALEIGH, Wake, NC | Pass | State |
| 2026-04-29 | 1804 LTD. LLC - SPRINGBROOK GAS PLANT - AQ | WILLISTON, Williams, ND | Pass | State |
| 2026-04-29 | SWIFT BEEF COMPANY — high-priority violation on file | GRAND ISLAND, Hall, NE | N/A | State |
| 2026-04-29 | GRANDI COMPRESSOR STATION | LOVING, Eddy, NM | Pass | State |
| 2026-04-29 | CHEVRON- CULEBRA BLUFF SECTION 26 CS | LOVING, Eddy, NM | Pass | State |
| 2026-04-29 | CHEVRON- CULEBRA BLUFF SECTION 26 CS | LOVING, Eddy, NM | Pass | State |
| 2026-04-29 | COLEMAN FACILITY | LOVING, Eddy, NM | Pass | State |
| 2026-04-29 | THISTLE COMPRESSOR STATION | JAL, Lea, NM | Pass | State |
| 2026-04-29 | THISTLE COMPRESSOR STATION | JAL, Lea, NM | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.