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 |
|---|---|---|---|---|
| 2026-03-31 | SAN JOAQUIN REFINING CO — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2026-03-31 | SAN JOAQUIN REFINING CO — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2026-03-31 | CALIFORNIA RESOURCES ELK HILLS LLC — high-priority violation on file | TUPMAN, Kern, CA | Pass | Local |
| 2026-03-31 | CALIFORNIA RESOURCES ELK HILLS LLC — high-priority violation on file | TUPMAN, Kern, CA | Pass | Local |
| 2026-03-31 | CALIFORNIA RESOURCES ELK HILLS LLC — high-priority violation on file | TUPMAN, Kern, CA | Pass | Local |
| 2026-03-31 | CALIFORNIA RESOURCES ELK HILLS LLC — high-priority violation on file | TUPMAN, Kern, CA | Pass | Local |
| 2026-03-31 | CALIFORNIA RESOURCES ELK HILLS LLC — high-priority violation on file | TUPMAN, Kern, CA | Pass | Local |
| 2026-03-31 | CALIFORNIA RESOURCES ELK HILLS LLC — high-priority violation on file | TUPMAN, Kern, CA | Pass | Local |
| 2026-03-31 | CALIFORNIA RESOURCES ELK HILLS LLC — high-priority violation on file | TUPMAN, Kern, CA | Pass | Local |
| 2026-03-31 | CALIFORNIA RESOURCES ELK HILLS LLC — high-priority violation on file | TUPMAN, Kern, CA | Pass | Local |
| 2026-03-31 | CALIFORNIA RESOURCES ELK HILLS LLC — high-priority violation on file | TUPMAN, Kern, CA | Pass | Local |
| 2026-03-31 | CALIFORNIA RESOURCES ELK HILLS LLC — high-priority violation on file | TUPMAN, Kern, CA | Pass | Local |
| 2026-03-31 | CALIFORNIA RESOURCES ELK HILLS LLC — high-priority violation on file | TUPMAN, Kern, CA | Pass | Local |
| 2026-03-31 | CALIFORNIA RESOURCES ELK HILLS LLC — high-priority violation on file | TUPMAN, Kern, CA | Pass | Local |
| 2026-03-31 | TRANSCOLORADO GAS - OLATHE C.S. | OLATHE 6.4 MI. SW OF, Montrose, CO | N/A | State |
| 2026-03-31 | TRANSCOLORADO GAS - OLATHE C.S. | OLATHE 6.4 MI. SW OF, Montrose, CO | Pass | State |
| 2026-03-31 | PUBLIC SERVICE CO - PAWNEE PLT — high-priority violation on file | BRUSH 2.6 MI. N OF, Morgan, CO | Pass | State |
| 2026-03-31 | IROQUOIS PIPELINE OPERATING COMPANY - BROOKFIELD COMPRESSOR STATION | BROOKFIELD, Fairfield, CT | Pass | State |
| 2026-03-31 | MOSAIC FERTILIZER, LLC | RIVERVIEW, Hillsborough, FL | Pass | State |
| 2026-03-31 | MOSAIC FERTILIZER, LLC | RIVERVIEW, Hillsborough, FL | Pass | State |
| 2026-03-31 | MOSAIC FERTILIZER LLC — high-priority violation on file | MULBERRY, Polk, FL | Pass | State |
| 2026-03-31 | MOSAIC FERTILIZER LLC — high-priority violation on file | MULBERRY, Polk, FL | Pass | State |
| 2026-03-31 | MOSAIC FERTILIZER LLC — high-priority violation on file | MULBERRY, Polk, FL | Pass | State |
| 2026-03-31 | PRATT PAPER (GA), LLC — high-priority violation on file | CONYERS, Rockdale, GA | Pass | State |
| 2026-03-31 | PRATT PAPER (GA), LLC — high-priority violation on file | CONYERS, Rockdale, GA | Pass | State |
| 2026-03-31 | PEOPLES GAS LIGHT & COKE CO | FISHER, Champaign, IL | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | MULZER CRUSHED STONE INCORPORATED (CAPE SANDY) A CRH COMPANY | LEAVENWORTH, Crawford, IN | Pass | State |
| 2026-03-31 | TOPPAN PACKAGING USA INC — high-priority violation on file | EDINBURGH, Johnson, IN | Fail | State |
| 2026-03-31 | BUCKEYE TERMINALS LLC HAMMOND TERMINAL | HAMMOND, Lake, IN | Pass | State |
| 2026-03-31 | BUCKEYE TERMINALS LLC HAMMOND TERMINAL | HAMMOND, Lake, IN | Pass | State |
| 2026-03-31 | METALX LLC DBA METALX WABASH | WABASH, Wabash, IN | Pass | State |
| 2026-03-31 | METALX LLC DBA METALX WABASH | WABASH, Wabash, IN | Pass | State |
| 2026-03-31 | METALX LLC DBA METALX WABASH | WABASH, Wabash, IN | Pass | State |
| 2026-03-31 | METALX LLC DBA METALX WABASH | WABASH, Wabash, IN | Pass | State |
| 2026-03-31 | MONTPELIER GENERATING STATION LLC — high-priority violation on file | PONETO, Wells, IN | Pass | State |
| 2026-03-31 | MONTPELIER GENERATING STATION LLC — high-priority violation on file | PONETO, Wells, IN | Pass | State |
| 2026-03-31 | MONTPELIER GENERATING STATION LLC — high-priority violation on file | PONETO, Wells, IN | Pass | State |
| 2026-03-31 | MONTPELIER GENERATING STATION LLC — high-priority violation on file | PONETO, Wells, IN | Pass | State |
| 2026-03-31 | OWENSBORO GRAIN CO LLC | OWENSBORO, Daviess, KY | Pass | State |
| 2026-03-31 | MICHIGAN STATE UNIVERSITY | EAST LANSING, Ingham, MI | Pass | State |
| 2026-03-31 | HERON LAKE BIOENERGY LLC | HERON LAKE, Jackson, MN | Pass | State |
| 2026-03-31 | ANDERSEN CORPORATION | BAYPORT, Washington, MN | Pass | State |
| 2026-03-31 | GCF US HOLDINGS, LLC - COLUMBUS MILL — high-priority violation on file | COLUMBUS, Lowndes, MS | Pass | State |
| 2026-03-31 | MSU - CENTRAL HEATING PLANT | BOZEMAN, Gallatin, MT | Pass | State |
| 2026-03-31 | STERICYCLE, INC. | HAW RIVER, Alamance, NC | Pass | State |
| 2026-03-31 | CITY OF GREENSBORO - T.Z. OSBORNE WATER RECLAMATION FACILITY — high-priority violation on file | MCLEANSVILLE, Guilford, NC | Pending | State |
| 2026-03-31 | NORTHERN BORDER PIPELINE COMPANY - ZEELAND COMPRESSOR STATION - AQ | ZEELAND, McIntosh, ND | Pass | State |
| 2026-03-31 | ONEOK ROCKIES MIDSTREAM, L.L.C. - GARDEN CREEK GAS PLANT - AQ | WATFORD CITY, McKenzie, ND | Pass | State |
| 2026-03-31 | OXY - CEDAR CANYON EAST COMPRESSOR STATION | MALAGA, Eddy, NM | Pass | State |
| 2026-03-31 | COTTON DRAW UNIT 26 CTB 2 | MALAGA, Eddy, NM | Pass | State |
| 2026-03-31 | COTTON DRAW UNIT 26 CTB 2 | MALAGA, Eddy, NM | Pass | State |
| 2026-03-31 | TRACE - HAWK COMPRESSOR STATION | LOCO HILLS, Eddy, NM | Pass | State |
| 2026-03-31 | TIGER COMPRESSOR STATION | CARLSBAD, Eddy, NM | Pass | State |
| 2026-03-31 | BENT TREE 9 CTB 2 | LA HUERTA, Eddy, NM | Pass | State |
| 2026-03-31 | WAYNE GAYLORD TB | LA HUERTA, Eddy, NM | Pass | State |
| 2026-03-31 | RAGIN CAJUN 12 CTB 3 | JAL, Lea, NM | Pass | State |
| 2026-03-31 | RAGIN CAJUN 12 CTB 3 | JAL, Lea, NM | Pass | State |
| 2026-03-31 | ALGONQUIN GAS: STONY POINT COMPRESSOR STA | STONY POINT, Rockland, NY | Pass | State |
| 2026-03-31 | RUFENER PAD 952860 | SARDIS, Monroe, OH | Pass | State |
| 2026-03-31 | RUFENER PAD 952860 | SARDIS, Monroe, OH | Pass | State |
| 2026-03-31 | RUFENER PAD 952860 | SARDIS, Monroe, OH | Pass | State |
| 2026-03-31 | BROWN COUNTY LANDFILL GAS POWER STATION | GEORGETOWN, Brown, OH | Pass | State |
| 2026-03-31 | BROWN COUNTY LANDFILL GAS POWER STATION | GEORGETOWN, Brown, OH | Pass | State |
| 2026-03-31 | BROWN COUNTY LANDFILL GAS POWER STATION | GEORGETOWN, Brown, OH | Pass | State |
| 2026-03-31 | BROWN COUNTY LANDFILL GAS POWER STATION | GEORGETOWN, Brown, OH | Pass | State |
| 2026-03-31 | BROWN COUNTY LANDFILL GAS POWER STATION | GEORGETOWN, Brown, OH | Pass | State |
| 2026-03-31 | BROWN COUNTY LANDFILL GAS POWER STATION | GEORGETOWN, Brown, OH | Pass | State |
| 2026-03-31 | BROWN COUNTY LANDFILL GAS POWER STATION | GEORGETOWN, Brown, OH | Pass | State |
| 2026-03-31 | BROWN COUNTY LANDFILL GAS POWER STATION | GEORGETOWN, Brown, OH | Pass | State |
| 2026-03-31 | BROWN COUNTY LANDFILL GAS POWER STATION | GEORGETOWN, Brown, OH | Pass | State |
| 2026-03-31 | WILLIAMS FIELD SVC CO LLC/TEEL COMP STA | SPRINGVILLE, Susquehanna, PA | Pass | State |
| 2026-03-31 | MARKWEST LIBERTY MIDSTREAM/BRIGICH COMP STA | CANONSBURG, Washington, PA | Pass | State |
| 2026-03-31 | EQM GATHERING OPCO LLC/KRYPTONITE COMP STA | WASHINGTON, Washington, PA | Pass | State |
| 2026-03-31 | BASIN ELECTRIC POWER COOPERATIVE GROTON GENERATING | GROTON, Brown, SD | Pass | State |
| 2026-03-31 | KENEDY GAS PLANT | KENEDY, Karnes, TX | Pass | State |
| 2026-03-31 | KENEDY GAS PLANT | KENEDY, Karnes, TX | Pass | State |
| 2026-03-31 | KENEDY GAS PLANT | KENEDY, Karnes, TX | Pass | State |
| 2026-03-31 | KENEDY GAS PLANT | KENEDY, Karnes, TX | Pass | State |
| 2026-03-31 | US NAVY - NAVAL STATION NORFOLK | NORFOLK, Norfolk (city), VA | Pass | State |
| 2026-03-31 | US NAVY - NAVAL STATION NORFOLK | NORFOLK, Norfolk (city), VA | Pass | State |
| 2026-03-31 | AHLSTROM COATED PRODUCTS LLC | RHINELANDER, Outagamie, WI | Pass | State |
| 2026-03-31 | US PAPER MILLS CORP - MENASHA MILL | MENASHA, Wood, WI | Pass | State |
| 2026-03-31 | MARKWEST LIBERTY MIDSTREAM & RESOURCES, L.L.C., MAJORSVILLE | DALLAS, Marshall, WV | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.