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 |
|---|---|---|---|---|
| 2026-05-05 | CTI OF NORTH CAROLINA, INC. | WILMINGTON, New Hanover, NC | Pending | State |
| 2026-05-05 | GEORGIA-PACIFIC GYPSUM LLC | NEWINGTON, Rockingham, NH | N/A | State |
| 2026-05-05 | TROJAN HORSE COMPRESSOR STATION | LOVING, Eddy, NM | Pass | State |
| 2026-05-05 | TROJAN HORSE COMPRESSOR STATION | LOVING, Eddy, NM | Pass | State |
| 2026-05-05 | RIPPLE COMPRESSOR STATION | MALAGA, Eddy, NM | Pass | State |
| 2026-05-05 | RIPPLE COMPRESSOR STATION | MALAGA, Eddy, NM | Pass | State |
| 2026-05-05 | RIPPLE COMPRESSOR STATION | MALAGA, Eddy, NM | Pass | State |
| 2026-05-05 | RIPPLE COMPRESSOR STATION | MALAGA, Eddy, NM | Pass | State |
| 2026-05-05 | CHEVRON U.S.A. INC - SALADO DRAW 23 COMPRESSOR STATION & TANK BATTERY — high-priority violation on file | JAL, Lea, NM | Pass | State |
| 2026-05-05 | CHEVRON U.S.A. INC - SALADO DRAW 23 COMPRESSOR STATION & TANK BATTERY — high-priority violation on file | JAL, Lea, NM | Pass | State |
| 2026-05-05 | ROVER PIPELINE - DEFIANCE COMPRESSOR STATION | DEFIANCE, Defiance, OH | Pass | State |
| 2026-05-05 | POET BIOREFINING - LEIPSIC — high-priority violation on file | LEIPSIC, Putnam, OH | Pass | State |
| 2026-05-05 | COLUMBIA PIPELINE GROUP-OAK HILL COMPRESSOR STATION | MADISON, TOWNSHIP OF, Jackson, OH | Pass | State |
| 2026-05-05 | COLUMBIA PIPELINE GROUP-OAK HILL COMPRESSOR STATION | MADISON, TOWNSHIP OF, Jackson, OH | Pass | State |
| 2026-05-05 | COLUMBIA PIPELINE GROUP-OAK HILL COMPRESSOR STATION | MADISON, TOWNSHIP OF, Jackson, OH | Pass | State |
| 2026-05-05 | CCL CONTAINER/ADVANCED MONOBLOC AEROSOL DIV — high-priority violation on file | HERMITAGE, Mercer, PA | Pass | State |
| 2026-05-05 | MONROE ENERGY LLC/TRAINER — high-priority violation on file | TRAINER, Delaware, PA | Pass | State |
| 2026-05-05 | HANOVER FOODS CORP/HANOVER CANNERY — high-priority violation on file | HANOVER, York, PA | Pass | State |
| 2026-05-05 | COLUMBIA GAS TRANS LLC/ARTEMAS COMP STA | ARTEMAS, Bedford, PA | Pass | State |
| 2026-05-05 | WILLIAMS FIELD SVC CO LLC/HAWLEY COMP STA | MONTROSE, Susquehanna, PA | Pass | State |
| 2026-05-05 | RANGE RESOURCES APPALACHIA/LAUREL HILL D 17531 PAD | TROUT RUN, Lycoming, PA | Pass | State |
| 2026-05-05 | SANTEE COOPER CROSS GENERATING STATION — high-priority violation on file | PINEVILLE, Berkeley, SC | Pass | State |
| 2026-05-05 | ASSOCIATED ASPHALT COLUMBIA LLC TA COLPROVIA ASPHALTS | COLUMBIA, Richland, SC | Pending | State |
| 2026-05-05 | COLUMBIA GULF TRANSMISSION CO. HARTSVILLE COMPRESSOR STATION | TENNESSEE, Undetermined, TN | Pass | State |
| 2026-05-05 | ALLEN COMBINED CYCLE PLANT - TVA | MEMPHIS, Shelby, TN | Pass | Local |
| 2026-05-05 | BADGER STATE ETHANOL, INC. — high-priority violation on file | MONROE, Green, WI | Pass | State |
| 2026-05-05 | NEENAH FOUNDRY COMPANY - NEENAH OPERATIONS (W2179) — high-priority violation on file | NEENAH, Wood, WI | Pass | State |
| 2026-05-05 | AMCOR FILMS | OSHKOSH, Wood, WI | Pass | State |
| 2026-05-05 | WYODAK PLANT (PACIFICORP) | GILLETTE, Campbell, WY | Pass | State |
| 2026-05-05 | NEIL SIMPSON COMPLEX (BLACK HILLS CORPORATION) | GILLETTE, Campbell, WY | Pass | State |
| 2026-05-05 | NEIL SIMPSON COMPLEX (BLACK HILLS CORPORATION) | GILLETTE, Campbell, WY | Pass | State |
| 2026-05-05 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-05-05 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-05-05 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-05-05 | ECHO SPRINGS GAS PLANT (WILLIAMS FIELD SERVICES) | CARBON COUNTY, Carbon, WY | Pass | State |
| 2026-05-05 | WESTVACO FACILITY (WE SODA WYOMING LP) | SWEETWATER COUNTY, Sweetwater, WY | Pass | State |
| 2026-05-04 | ROBERT'S TRUST COMPRESSOR STATION | DUNN COUNTY, Dunn, ND | Pass | U.S. EPA |
| 2026-05-04 | ROBERT'S TRUST COMPRESSOR STATION | DUNN COUNTY, Dunn, ND | Pass | U.S. EPA |
| 2026-05-04 | HILCORP ALASKA, LLC / OOOGURUK DEVELOPMENT PROJECT | NORTH SLOPE BOROUGH, North Slope, AK | Pass | State |
| 2026-05-04 | INTERNATIONAL PAPER COMPANY | PRATTVILLE, Autauga, AL | Pass | State |
| 2026-05-04 | INTERNATIONAL PAPER COMPANY | PRATTVILLE, Autauga, AL | Pass | State |
| 2026-05-04 | DESOTO GATHERING COMPANY, LLC - NEW QUITMAN CPF-2 | QUITMAN, Faulkner, AR | Pass | State |
| 2026-05-04 | DESOTO GATHERING COMPANY LLC - NEW QUITMAN CPF-4 | QUITMAN, Faulkner, AR | Pass | State |
| 2026-05-04 | TESORO REFINING & MARKETING CO, LLC — high-priority violation on file | CARSON, Los Angeles, CA | Pass | Local |
| 2026-05-04 | DARLING INTERNATIONAL | CROWS LANDING, Stanislaus, CA | Fail | Local |
| 2026-05-04 | DARLING INTERNATIONAL | CROWS LANDING, Stanislaus, CA | Fail | Local |
| 2026-05-04 | DARLING INTERNATIONAL | CROWS LANDING, Stanislaus, CA | Fail | Local |
| 2026-05-04 | DARLING INTERNATIONAL | CROWS LANDING, Stanislaus, CA | Fail | Local |
| 2026-05-04 | DARLING INTERNATIONAL | CROWS LANDING, Stanislaus, CA | Fail | Local |
| 2026-05-04 | DARLING INTERNATIONAL | CROWS LANDING, Stanislaus, CA | Fail | Local |
| 2026-05-04 | ALLIED WASTE SYSTEMS - TOWER LANDFILL | COMMERCE CITY, Adams, CO | Pending | State |
| 2026-05-04 | INTERNATIONAL PAPER - FLINT RIVER MILL | OGLETHORPE, Macon, GA | Pass | State |
| 2026-05-04 | MAQUOKETA MUNICIPAL ELECTRIC UTILITY-N&S | MAQUOKETA (HISTORICAL), Jackson, IA | Pass | State |
| 2026-05-04 | LSP COTTAGE GROVE COGENERATION FACILITY | COTTAGE GROVE, Washington, MN | Pass | State |
| 2026-05-04 | PCS PHOSPHATE COMPANY, INC. - AURORA | AURORA, Beaufort, NC | Pass | State |
| 2026-05-04 | S. T. WOOTEN CORPORATION - SANFORD ASPHALT PLANT | SANFORD, Lee, NC | Pass | State |
| 2026-05-04 | CAMACHO COMPRESSOR STATION | CARLSBAD, Eddy, NM | Pass | State |
| 2026-05-04 | HARRIER COMPRESSOR STATION | JAL, Lea, NM | Pass | State |
| 2026-05-04 | ROVER PIPELINE - DEFIANCE COMPRESSOR STATION | DEFIANCE, Defiance, OH | Pass | State |
| 2026-05-04 | ROVER PIPELINE - DEFIANCE COMPRESSOR STATION | DEFIANCE, Defiance, OH | Pass | State |
| 2026-05-04 | SURTECO NORTH AMER INC/AUBURN PLT FKA RENEER FILMS — high-priority violation on file | AUBURN, Schuylkill, PA | Pending | State |
| 2026-05-04 | WABTEC US RAIL GROVE CITY ENGINE/MERCER | GROVE CITY, Mercer, PA | Pass | State |
| 2026-05-04 | MARKWEST LIBERTY MIDSTREAM & RESOURCES/REDD COMP STA | WASHINGTON, Washington, PA | Pass | State |
| 2026-05-04 | WILLIAMS FIELD SVC CO/MACNEW COMP STA | HOP BOTTOM, Susquehanna, PA | Pass | State |
| 2026-05-04 | JKLM ENERGY LLC/HEADWATERS 145 WELL PAD | ULYSSES, Potter, PA | Pass | State |
| 2026-05-04 | EXPAND OPERATING LLC/GU-VW MCMAHON WELL PAD | STEVENSVILLE, Bradford, PA | Pass | State |
| 2026-05-04 | WPL - NEENAH GENERATING FACILITY — high-priority violation on file | NEENAH, Winnebago, WI | Pass | State |
| 2026-05-04 | WPL - NEENAH GENERATING FACILITY — high-priority violation on file | NEENAH, Winnebago, WI | Pass | State |
| 2026-05-03 | NUCOR STEEL - HERTFORD | COFIELD, Hertford, NC | Pass | State |
| 2026-05-02 | TOMB RAIDER 1 CTB 3 | MALAGA, Eddy, NM | Pass | State |
| 2026-05-02 | SERPENTINE 2 FACILITY 1 | EUNICE, Lea, NM | Pass | State |
| 2026-05-02 | ELLWOOD ENGINEERED CASTINGS | HUBBARD, Trumbull, OH | Pass | State |
| 2026-05-02 | ELLWOOD ENGINEERED CASTINGS | HUBBARD, Trumbull, OH | Pass | State |
| 2026-05-02 | ELLWOOD ENGINEERED CASTINGS | HUBBARD, Trumbull, OH | Pass | State |
| 2026-05-02 | ELLWOOD ENGINEERED CASTINGS | HUBBARD, Trumbull, OH | Pass | State |
| 2026-05-02 | ELLWOOD ENGINEERED CASTINGS | HUBBARD, Trumbull, OH | Pass | State |
| 2026-05-02 | ELLWOOD ENGINEERED CASTINGS | HUBBARD, Trumbull, OH | Pass | State |
| 2026-05-02 | ELLWOOD ENGINEERED CASTINGS | HUBBARD, Trumbull, OH | Pass | State |
| 2026-05-02 | ELLWOOD ENGINEERED CASTINGS | HUBBARD, Trumbull, OH | Pass | State |
| 2026-05-01 | HILCORP ALASKA, LLC / TYONEK PLATFORM | KENAI, Kenai Peninsula, AK | Pending | State |
| 2026-05-01 | NATIONAL CEMENT CO OF ALABAMA — high-priority violation on file | RAGLAND, St. Clair, AL | Pass | State |
| 2026-05-01 | NATIONAL CEMENT CO OF ALABAMA — high-priority violation on file | RAGLAND, St. Clair, AL | Pass | State |
| 2026-05-01 | SO CAL GAS - NEWBERRY SPRINGS | NEWBERRY SPRINGS, San Bernardino, CA | Pass | Local |
| 2026-05-01 | PREGIS INNOVATIVE PACKAGING INC | VISALIA, Tulare, CA | Pass | Local |
| 2026-05-01 | PREGIS INNOVATIVE PACKAGING INC | VISALIA, Tulare, CA | Pass | Local |
| 2026-05-01 | PREGIS INNOVATIVE PACKAGING INC | VISALIA, Tulare, CA | Pass | Local |
| 2026-05-01 | PREGIS INNOVATIVE PACKAGING INC | VISALIA, Tulare, CA | Pass | Local |
| 2026-05-01 | PREGIS INNOVATIVE PACKAGING INC | VISALIA, Tulare, CA | Pass | Local |
| 2026-05-01 | PREGIS INNOVATIVE PACKAGING INC | VISALIA, Tulare, CA | Pass | Local |
| 2026-05-01 | PLAINS END, LLC | ARVADA, Jefferson, CO | Pass | State |
| 2026-05-01 | MIDDLETOWN POWER LLC | MIDDLETOWN, Middlesex, CT | Pending | State |
| 2026-05-01 | TILCON CONNECTICUT - WATERBURY PLANT | WATERBURY, New Haven, CT | Fail | State |
| 2026-05-01 | GALLAUDET UNIVERSITY — high-priority violation on file | WASHINGTON, District of Columbia, DC | Pass | State |
| 2026-05-01 | GALLAUDET UNIVERSITY — high-priority violation on file | WASHINGTON, District of Columbia, DC | Pass | State |
| 2026-05-01 | ILLINOIS CEMENT CO | LASALLE, La Salle, IL | Pass | State |
| 2026-05-01 | ALAMANCE AGGREGATES, LLC | SNOW CAMP, Alamance, NC | Pending | State |
| 2026-05-01 | CASA BONITA COMPRESSOR STATION | LOVING, Eddy, NM | Pass | State |
| 2026-05-01 | CASA BONITA COMPRESSOR STATION | LOVING, Eddy, NM | 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 |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.