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 |
|---|---|---|---|---|
| 2026-06-23 | US STEEL CORPORATION GARY WORKS — high-priority violation on file | GARY, Lake, IN | Pass | State |
| 2026-06-23 | US STEEL CORPORATION GARY WORKS — high-priority violation on file | GARY, Lake, IN | Pass | State |
| 2026-06-23 | US STEEL CORPORATION GARY WORKS — high-priority violation on file | GARY, Lake, IN | Pass | State |
| 2026-06-23 | TENNESSEE VALLEY AUTHORITY (TVA) - SHAWNEE FOSSIL PLANT | WEST PADUCAH, McCracken, KY | Pass | State |
| 2026-06-23 | AMRIZE CEMENT INC. — high-priority violation on file | ALPENA, Alpena, MI | Pass | State |
| 2026-06-23 | CONSUMERS ENERGY D.E. KARN FACILITY | ESSEXVILLE, Bay, MI | Pass | State |
| 2026-06-23 | PACKAGING CORPORATION OF AMERICA - FILER CITY MILL | FILER CITY, Manistee, MI | Pass | State |
| 2026-06-23 | TILDEN MINING COMPANY LC | ISHPEMING, Marquette, MI | Pass | State |
| 2026-06-23 | EVERGY-HAWTHORN GENERATING STATION | KANSAS CITY, Jackson, MO | Pass | State |
| 2026-06-23 | EVERGY-HAWTHORN GENERATING STATION | KANSAS CITY, Jackson, MO | Pass | State |
| 2026-06-23 | EVERGY-HAWTHORN GENERATING STATION | KANSAS CITY, Jackson, MO | N/A | State |
| 2026-06-23 | AMRIZE RAVENA FACILITY | COEYMANS, Albany, NY | Pass | State |
| 2026-06-23 | TEXAS EASTERN TRANS LP/UNIONTOWN STA — high-priority violation on file | LEMONT FURNACE, Fayette, PA | Pass | State |
| 2026-06-23 | CONSOL PA COAL CO LLC/BAILEY PREP PLT — high-priority violation on file | WEST FINLEY, Greene, PA | Pass | State |
| 2026-06-23 | BUCKEYE TERM LLC/MALVERN TERM | MALVERN, Chester, PA | Pass | State |
| 2026-06-23 | MARKWEST LIBERTY MIDSTREAM & RESOURCES/NANCY STEWART | MOUNT PLEASANT, Washington, PA | Pass | State |
| 2026-06-23 | EXPAND RUTH WYO PAD | MESHOPPEN, Wyoming, PA | Pass | State |
| 2026-06-23 | EQT ARTEMIS MIDSTREAM LLC/GUARDIAN COMP STA | IRWIN, Westmoreland, PA | Pass | State |
| 2026-06-23 | MID-CONTINENT COAL AND COKE COMPANY | HUGER, Berkeley, SC | Pending | State |
| 2026-06-23 | DOMTAR PAPER COMPANY LLC | BENNETTSVILLE, Marlboro, SC | Pass | State |
| 2026-06-23 | POET BIOREFINING - MITCHELL LLC | MITCHELL, Davison, SD | Pass | State |
| 2026-06-23 | AMRIZE CEMENT/FORMERLY HOLCIM (US), INC. — high-priority violation on file | MORGAN, Morgan, UT | Pass | State |
| 2026-06-23 | AMRIZE CEMENT/FORMERLY HOLCIM (US), INC. — high-priority violation on file | MORGAN, Morgan, UT | Pass | State |
| 2026-06-23 | MG&E WEST CAMPUS COGENERATION FTY | MADISON, Dane, WI | Pass | State |
| 2026-06-23 | WI PUBLIC SERVICE WESTON POWER PLANT | KRONENWETTER, Marathon, WI | Pass | State |
| 2026-06-23 | WI PUBLIC SERVICE WESTON POWER PLANT | KRONENWETTER, Marathon, WI | Pass | State |
| 2026-06-23 | HANSEN LAKE COMPRESSOR STATION (WILLIAMS FIELD SERVICES CO.) | SWEETWATER COUNTY, Sweetwater, WY | Pass | State |
| 2026-06-23 | HANSEN LAKE COMPRESSOR STATION (WILLIAMS FIELD SERVICES CO.) | SWEETWATER COUNTY, Sweetwater, WY | Pass | State |
| 2026-06-22 | PETRO STAR, INC. / PETRO STAR VALDEZ REFINERY — high-priority violation on file | VALDEZ, Valdez-Cordova (CA), AK | Pass | State |
| 2026-06-22 | PETRO STAR, INC. / PETRO STAR VALDEZ REFINERY — high-priority violation on file | VALDEZ, Valdez-Cordova (CA), AK | Pass | State |
| 2026-06-22 | COLASKA, INC. DBA UNIVERSITY REDI-MIX / SOUTHSIDE PIT ASPHALT PLANT, NORTH POLE | ALASKA, Undetermined, AK | Pass | State |
| 2026-06-22 | GEORGIA PACIFIC | PENNINGTON, Choctaw, AL | Pass | State |
| 2026-06-22 | SOUTH FLORIDA WATER MANAGEMENT DISTRICT | PALM BEACH COUNTY, Palm Beach, FL | Pass | State |
| 2026-06-22 | SOUTH FLORIDA WATER MANAGEMENT DISTRICT | PALM BEACH COUNTY, Palm Beach, FL | Pass | State |
| 2026-06-22 | TEXAS EASTERN TRANSMISSION | ACCIDENT, Garrett, MD | Pass | State |
| 2026-06-22 | DUNBAR COMPRESSOR STATION | WINDSOR, Broome, NY | Pass | State |
| 2026-06-22 | LONGHORN PAD C/ELK | WEEDVILLE, Elk, PA | Pass | State |
| 2026-06-22 | UNITED ENERGY NECEDAH LLC — high-priority violation on file | NECEDAH, Juneau, WI | Pass | State |
| 2026-06-22 | WASTE MANAGEMENT OF WISCONSIN, INC. - PHEASANT RUN RECYCLING AND DISPOSAL FACILI | BRISTOL, Kenosha, WI | Pass | State |
| 2026-06-22 | WI PUBLIC SERVICE WESTON POWER PLANT | KRONENWETTER, Marathon, WI | Pass | State |
| 2026-06-22 | WMWI - METRO RECYCLING & DISPOSAL | FRANKLIN, Monroe, WI | Pass | State |
| 2026-06-22 | WMWI - METRO RECYCLING & DISPOSAL | FRANKLIN, Monroe, WI | Pass | State |
| 2026-06-22 | WPL - EDGEWATER GENERATING STATION | SHEBOYGAN, Taylor, WI | Pass | State |
| 2026-06-22 | LEAVITT COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-06-22 | LEAVITT COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-06-22 | LEAVITT COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-06-22 | LEAVITT COMPRESSOR STATION (THUNDER CREEK GAS SERVICES) | CAMPBELL COUNTY, Campbell, WY | Pass | State |
| 2026-06-19 | TESORO LOGISTICS OPERATIONS, LLC / NIKISKI TERMINAL | KENAI, Kenai Peninsula, AK | Pass | State |
| 2026-06-19 | TRANSCONTINENTAL GAS PIPE LINE COMPANY L | WADLEY, Randolph, AL | Pass | State |
| 2026-06-19 | DCP OPERATING CO - O'CONNOR GAS PLANT | KERSEY AREA, Weld, CO | Pass | State |
| 2026-06-19 | ASCEND PERFORMANCE MATERIALS OPERATIONS — high-priority violation on file | CANTONMENT, Escambia, FL | Pass | State |
| 2026-06-19 | ASCEND PERFORMANCE MATERIALS OPERATIONS — high-priority violation on file | CANTONMENT, Escambia, FL | Pass | State |
| 2026-06-19 | ASCEND PERFORMANCE MATERIALS OPERATIONS — high-priority violation on file | CANTONMENT, Escambia, FL | Pass | State |
| 2026-06-19 | DUKE ENERGY FLORIDA, LLC | FORT MEADE, Polk, FL | Pass | State |
| 2026-06-19 | DUKE ENERGY FLORIDA, LLC | FORT MEADE, Polk, FL | Pass | State |
| 2026-06-19 | DYNEGY MIDWEST GENERATION LLC | BALDWIN, Randolph, IL | Pass | State |
| 2026-06-19 | CARB RITE COMPANY | SCHNEIDER, Lake, IN | Pass | State |
| 2026-06-19 | CARB RITE COMPANY | SCHNEIDER, Lake, IN | Pass | State |
| 2026-06-19 | CARB RITE COMPANY | SCHNEIDER, Lake, IN | Pass | State |
| 2026-06-19 | CARB RITE COMPANY | SCHNEIDER, Lake, IN | Pass | State |
| 2026-06-19 | GENERAL CONTRACTOR VAUGHN D. THIBODEAU, II, INC. | PROSPECT, Waldo, ME | Fail | State |
| 2026-06-19 | OTSEGO PAPER INC. | OTSEGO, Allegan, MI | Pass | State |
| 2026-06-19 | PIEDMONT AVIATION COMPONENT SERVICES | GREENSBORO, Guilford, NC | Pending | State |
| 2026-06-19 | ASCENT RESOURCES - UTICA LLC - COLAIANNI MTP JF | ADENA, Jefferson, OH | Pass | State |
| 2026-06-19 | ASCENT RESOURCES - UTICA LLC - COLAIANNI MTP JF | ADENA, Jefferson, OH | Pass | State |
| 2026-06-19 | ASCENT RESOURCES - UTICA LLC - COLAIANNI MTP JF | ADENA, Jefferson, OH | Pass | State |
| 2026-06-19 | SCRUBGRASS GENERATING PLT/VENANGO — high-priority violation on file | KENNERDELL, Venango, PA | Pass | State |
| 2026-06-19 | REGENCY MARCELLUS GAS GATHERING LLC/QUAKER STATE RD COMP STA | MONTOURSVILLE, Lycoming, PA | Pass | State |
| 2026-06-19 | CNX MIDSTREAM OPR CO LLC /MORRIS DEHY STATION | GRAYSVILLE, Greene, PA | Pass | State |
| 2026-06-19 | USS/CLAIRTON WORKS — high-priority violation on file | CLAIRTON, Allegheny, PA | Pass | Local |
| 2026-06-19 | ADVANSIX (FORMERLY HONEYWELL/FRANKFORD PLT) — high-priority violation on file | PHILADELPHIA, Philadelphia, PA | Pending | Local |
| 2026-06-19 | AMRIZE CEMENT INC. - HOLLY HILL PLANT | HOLLY HILL, Orangeburg, SC | Pending | State |
| 2026-06-19 | GCC DACOTAH — high-priority violation on file | RAPID CITY, Pennington, SD | Pass | State |
| 2026-06-19 | BLUES CITY BREWERY,LLC — high-priority violation on file | MEMPHIS, Shelby, TN | Pass | Local |
| 2026-06-19 | DOMINION - POSSUM POINT POWER STATION | DUMFRIES, Prince William, VA | Pending | State |
| 2026-06-19 | DOMINION - POSSUM POINT POWER STATION | DUMFRIES, Prince William, VA | Pending | State |
| 2026-06-19 | MONONGAHELA POWER COMPANY, HARRISON STATION | HAYWOOD, Harrison, WV | Pass | State |
| 2026-06-19 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-06-19 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-06-19 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-06-19 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-06-19 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-06-19 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-06-18 | TESORO ALASKA COMPANY, LLC / KENAI REFINERY — high-priority violation on file | KENAI, Kenai Peninsula, AK | Pass | State |
| 2026-06-18 | SUZANO PACKAGING, LLC | PINE BLUFF, Jefferson, AR | Pass | State |
| 2026-06-18 | SUZANO PACKAGING, LLC | PINE BLUFF, Jefferson, AR | Pass | State |
| 2026-06-18 | PUBLIC SERVICE CO - CHEROKEE PLT | COMMERCE CITY AREA, Adams, CO | Pass | State |
| 2026-06-18 | TRI STATE GENERATION & TRANS - CRAIG | CRAIG 2.9 MI. SW OF, Moffat, CO | Pending | State |
| 2026-06-18 | EAST SHORE WATER POLL ABATEMENT FACILITY | NEW HAVEN, New Haven, CT | Pass | State |
| 2026-06-18 | SEMINOLE ELECTRIC COOPERATIVE, INC. | BOWLING GREEN, Hardee, FL | Pass | State |
| 2026-06-18 | DUKE ENERGY FLORIDA, LLC | BARTOW, Polk, FL | Pass | State |
| 2026-06-18 | THE ANDERSONS MARATHON HOLDINGS LLC — high-priority violation on file | DENISON, Crawford, IA | Pass | State |
| 2026-06-18 | THE ANDERSONS MARATHON HOLDINGS LLC — high-priority violation on file | DENISON, Crawford, IA | Pass | State |
| 2026-06-18 | MICROSOFT CORPORATION - WILLOW CREEK/GINGER EAST DATA | DES MOINES, Polk, IA | Pass | Local |
| 2026-06-18 | CITY OF CASEY | CASEY, Clark, IL | Pass | State |
| 2026-06-18 | CITY OF CASEY | CASEY, Clark, IL | Pass | State |
| 2026-06-18 | NIBLOCK EXCAVATING INC | BRISTOL, Elkhart, IN | Pass | State |
| 2026-06-18 | SOUTH SHORE SLAG LLC CONTRACTOR OF US STEEL CORPORATION GARY | GARY, Lake, IN | Pass | State |
| 2026-06-18 | RIETH RILEY ASPHALT PLANT NO 366 | LA PORTE, LaPorte, IN | Pass | State |
| 2026-06-18 | RIETH RILEY ASPHALT PLANT NO 366 | LA PORTE, LaPorte, IN | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.