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 |
|---|---|---|---|---|
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | MARKWEST YODER COMPRESSOR STATION | CADIZ, Harrison, OH | Pass | State |
| 2026-05-01 | BOYAS EXCAVATING, INC. | VALLEY VIEW, Cuyahoga, OH | Pass | State |
| 2026-05-01 | EXPAND OPERATING LLC/NR-23 FOUR BUCKS PAD | SUSQUEHANNA, Susquehanna, PA | Pass | State |
| 2026-05-01 | MOGRIDGE, C. PAD 1 — high-priority violation on file | SPRINGVILLE, Susquehanna, PA | Pass | State |
| 2026-05-01 | BERKELEY COUNTY LANDFILL | MONCKS CORNER, Berkeley, SC | Pending | State |
| 2026-05-01 | WESTROCK CP LLC - WEST POINT | WEST POINT, King William, VA | Pass | State |
| 2026-04-30 | ARKEMA INC | AXIS, Mobile, AL | Pass | State |
| 2026-04-30 | ET GATHERING & PROCESSING LLC - WASHBURN COMPRESSOR STATION | GREENWOOD, Sebastian, AR | Pass | State |
| 2026-04-30 | MCGEORGE CONTRACTING CO. - CRANFORD CONSTRUCTION DIVISION - JONES MILL ASPHALT — high-priority violation on file | MALVERN, Hot Spring, AR | Pass | State |
| 2026-04-30 | LINDE GAS & EQUIPMENT, INC. | KINGMAN, Mohave, AZ | Pass | State |
| 2026-04-30 | CAL PORTLAND CEMENT | ORO GRANDE, San Bernardino, CA | Pass | Local |
| 2026-04-30 | SACRAMENTO MUNICIPAL UTILITY DIST. FINANCING AUTHORITY DBA PROCTER GAMBLE POWER — high-priority violation on file | SACRAMENTO, Sacramento, CA | Pending | Local |
| 2026-04-30 | EF OXNARD LLC | OXNARD, Ventura, CA | Pass | Local |
| 2026-04-30 | PLAINS END, LLC | ARVADA, Jefferson, CO | Pass | State |
| 2026-04-30 | OWENS CORNING ASPHALT ROOFING, LLC | JACKSONVILLE, Duval, FL | Pass | State |
| 2026-04-30 | BUILDING MATERIALS MANUFACTURING LLC — high-priority violation on file | TAMPA, Hillsborough, FL | Pass | State |
| 2026-04-30 | SOLID WASTE AUTHORITY OF PBC | WEST PALM BEACH, Palm Beach, FL | Pass | State |
| 2026-04-30 | TAMPA ELECTRIC COMPANY | MULBERRY, Polk, FL | Pass | State |
| 2026-04-30 | TAMPA ELECTRIC COMPANY | MULBERRY, Polk, FL | Pass | State |
| 2026-04-30 | RM CLAYTON WATER RECLAMATION CENTER — high-priority violation on file | ATLANTA, Fulton, GA | Pass | State |
| 2026-04-30 | RM CLAYTON WATER RECLAMATION CENTER — high-priority violation on file | ATLANTA, Fulton, GA | Pass | State |
| 2026-04-30 | HOMELAND ENERGY SOLUTIONS LLC — high-priority violation on file | LAWLER, Chickasaw, IA | Pass | State |
| 2026-04-30 | HOMELAND ENERGY SOLUTIONS LLC — high-priority violation on file | LAWLER, Chickasaw, IA | Pass | State |
| 2026-04-30 | GUARDIAN INDUSTRIES CORP | DE WITT, Clinton, IA | Pass | State |
| 2026-04-30 | SIOUX CITY BRICK & TILE CO | SERGEANT BLUFF, Woodbury, IA | Pass | State |
| 2026-04-30 | MICROSOFT CORPORATION - WILLOW CREEK/GINGER EAST DATA | DES MOINES, Polk, IA | Fail | Local |
| 2026-04-30 | WESTERN CONSTRUCTION - BOISE | BOISE, Ada, ID | Pass | State |
| 2026-04-30 | WESTERN CONSTRUCTION 00098 | BOISE, Ada, ID | Pass | State |
| 2026-04-30 | WESTERN CONSTRUCTION 00604 | BOISE, Ada, ID | Pass | State |
| 2026-04-30 | WESTERN CONSTRUCTION 00605 | BOISE, Ada, ID | Pass | State |
| 2026-04-30 | WESTERN CONSTRUCTION INC 00680 | BOISE, Ada, ID | Pass | State |
| 2026-04-30 | WESTERN CONSTRUCTION INC 00682 | BOISE, Ada, ID | Pass | State |
| 2026-04-30 | WESTERN CONSTRUCTION INC 00683 | BOISE, Ada, ID | Pass | State |
| 2026-04-30 | TATE & LYLE SOLUTIONS USA LLC — high-priority violation on file | LAFAYETTE, Tippecanoe, IN | Pass | State |
| 2026-04-30 | STEEL DYNAMICS, INC. STRUCTURAL & RAIL DIVISION — high-priority violation on file | COLUMBIA CITY, Whitley, IN | Pass | State |
| 2026-04-30 | IOLA MUN. POWER PLANT #1 (AIR) | IOLA, Allen, KS | Pass | State |
| 2026-04-30 | TEMPERFORM LLC | NOVI, Oakland, MI | Pass | State |
| 2026-04-30 | GUARDIAN ENERGY LLC | JANESVILLE, Waseca, MN | Pass | State |
| 2026-04-30 | CALGON CARBON CORPORATION | BAY ST. LOUI, Hancock, MS | Pass | State |
| 2026-04-30 | WILLISTON BASIN - CABIN CREEK | BAKER, Fallon, MT | Fail | State |
| 2026-04-30 | 1804 LTD. LLC - SPRINGBROOK GAS PLANT - AQ | WILLISTON, Williams, ND | Pass | State |
| 2026-04-30 | LOST TANK 13 BOO STATION | LOVING, Eddy, NM | Pass | State |
| 2026-04-30 | JAMES 29 FEDERAL BATTERY | LOVING, Lea, NM | Pass | State |
| 2026-04-30 | MARGARITA CTB | MONUMENT, Lea, NM | Pass | State |
| 2026-04-30 | PAUL FLOWERS TB | MONUMENT, Lea, NM | Pass | State |
| 2026-04-30 | NYC DOT-HAMILTON AVE ASPHALT PLANT | BROOKLYN, Kings, NY | Pass | State |
| 2026-04-30 | CALPINE JFK ENERGY CENTER | JAMAICA, Queens, NY | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Fail | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Fail | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Fail | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Fail | State |
| 2026-04-30 | CLARIOS, LLC. | HOLLAND, Lucas, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, OH | Pass | State |
| 2026-04-30 | EQM OLYMPUS - TITAN COMPRESSOR STATION | WASHINGTON, TOWNSHIP OF, Belmont, 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 |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.