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 |
|---|---|---|---|---|
| 2026-03-16 | APPALACHIA MIDSTREAM SERVICES, L.L.C., BUFFALO STATION | BETHANY, Brooke, WV | Pass | State |
| 2026-03-15 | OMNIS PLEASANTS, LLC, PLEASANTS POWER STATION | WILLOW ISLAND, Pleasants, WV | Pass | State |
| 2026-03-15 | OMNIS PLEASANTS, LLC, PLEASANTS POWER STATION | WILLOW ISLAND, Pleasants, WV | Pass | State |
| 2026-03-14 | HYBAR LLC | OSCEOLA, Mississippi, AR | Pass | State |
| 2026-03-14 | HYBAR LLC | OSCEOLA, Mississippi, AR | Pass | State |
| 2026-03-14 | U.S. ENERGY MILWAUKEE JONES ISLAND TERMINAL | MILWAUKEE, Monroe, WI | Pass | State |
| 2026-03-13 | KINDER MORGAN LIQUIDS TERMINALS LLC | WOOD RIVER, Madison, IL | Pass | State |
| 2026-03-13 | WHEELABRATOR MILLBURY INC | MILLBURY, Worcester, MA | Pending | State |
| 2026-03-13 | CLARIOS, LLC | SAINT JOSEPH, Buchanan, MO | Pass | State |
| 2026-03-13 | CLARIOS, LLC | SAINT JOSEPH, Buchanan, MO | Pass | State |
| 2026-03-13 | CLARIOS, LLC | SAINT JOSEPH, Buchanan, MO | Pass | State |
| 2026-03-13 | CLARIOS, LLC | SAINT JOSEPH, Buchanan, MO | Pass | State |
| 2026-03-13 | GULF SOUTH PIPELINE COMPANY LLC, MOSS POINT COMPRESSOR STATION | MOSS POINT, Jackson, MS | Pass | State |
| 2026-03-13 | GULF SOUTH PIPELINE COMPANY LLC, MOSS POINT COMPRESSOR STATION | MOSS POINT, Jackson, MS | Pass | State |
| 2026-03-13 | GULF SOUTH PIPELINE COMPANY LLC, MOSS POINT COMPRESSOR STATION | MOSS POINT, Jackson, MS | Pass | State |
| 2026-03-13 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2026-03-13 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2026-03-13 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2026-03-13 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2026-03-13 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2026-03-13 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2026-03-13 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2026-03-13 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2026-03-13 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2026-03-13 | BASIN CREEK POWER SERVICES | BUTTE, Silver Bow, MT | Pass | State |
| 2026-03-13 | DEVON - TODD 36 CTB 3 & CTB 2 | MALAGA, Eddy, NM | Pass | State |
| 2026-03-13 | INDIAN FLATS BOOSTER STATION | CARLSBAD, Eddy, NM | Pass | State |
| 2026-03-13 | RED ROCK COMPRESSOR STATION | CARLSBAD, Eddy, NM | Pass | State |
| 2026-03-13 | BILL WILSHUSEN TB | LA HUERTA, Eddy, NM | Pass | State |
| 2026-03-13 | AVALON COMPRESSOR STATION | LOVING, Eddy, NM | Pass | State |
| 2026-03-13 | AVALON COMPRESSOR STATION | LOVING, Eddy, NM | Pass | State |
| 2026-03-13 | IGGLES TB | MONUMENT, Lea, NM | Pass | State |
| 2026-03-13 | IGGLES TB | MONUMENT, Lea, NM | Pass | State |
| 2026-03-13 | BLUE RACER MIDSTREAM, LLC - HAYES STATION | SALESVILLE, Guernsey, OH | Pass | State |
| 2026-03-13 | BLUE RACER MIDSTREAM, LLC - HAYES STATION | SALESVILLE, Guernsey, OH | Pass | State |
| 2026-03-13 | BLUE RACER MIDSTREAM, LLC - HAYES STATION | SALESVILLE, Guernsey, OH | Pass | State |
| 2026-03-13 | KEYSTONE CONEMAUGH PROJ LLC/KEYSTONE STATION | SHELOCTA, Armstrong, PA | Pass | State |
| 2026-03-13 | WILLIAMS FIELD SVC CO LLC/CHURCH COMP STA | SPRINGVILLE, Susquehanna, PA | Pass | State |
| 2026-03-13 | SNYDER BROS INC/WHITE COMP STA | KITTANNING, Armstrong, PA | Pass | State |
| 2026-03-13 | COMPASS IAD DATACENTER | LEESBURG, Loudoun, VA | Pass | State |
| 2026-03-13 | CHARLESTON AREA MEDICAL CENTER, INC., GENERAL HOSPITAL | CHARLESTON, Kanawha, WV | Pass | State |
| 2026-03-13 | OMNIS PLEASANTS, LLC, PLEASANTS POWER STATION | WILLOW ISLAND, Pleasants, WV | Pass | State |
| 2026-03-12 | HILCORP ALASKA, LLC / LISBURNE PRODUCTION CENTER (LPC) | NORTH SLOPE BOROUGH, North Slope, AK | Pass | State |
| 2026-03-12 | BOISE WHITE PAPER LLC | JACKSON, Clarke, AL | Pass | State |
| 2026-03-12 | BOISE WHITE PAPER LLC | JACKSON, Clarke, AL | Pass | State |
| 2026-03-12 | W&T OFFSHORE, INC. | THEODORE, Mobile, AL | Pass | State |
| 2026-03-12 | W&T OFFSHORE, INC. | THEODORE, Mobile, AL | Pass | State |
| 2026-03-12 | DESOTO GATHERING COMPANY, LLC - YELLOWSTONE CPF-3 | BEE BRANCH, Van Buren, AR | Pass | State |
| 2026-03-12 | COSUMNES POWER PLANT / SMUD | HERALD, Sacramento, CA | Pass | Local |
| 2026-03-12 | AMERICAN UNIVERSITY | WASHINGTON, District of Columbia, DC | Pass | State |
| 2026-03-12 | BALL METAL BEVERAGE CONTAINER CORP. | TAMPA, Hillsborough, FL | Pass | State |
| 2026-03-12 | BALL METAL BEVERAGE CONTAINER CORP. | TAMPA, Hillsborough, FL | Pass | State |
| 2026-03-12 | SOUTHERN NATURAL GAS CO., L.L.C - HALL GATE COMP. STATION | MILLEDGEVILLE, Baldwin, GA | Pass | State |
| 2026-03-12 | LOCKHEED MARTIN AERONAUTICS CO. | MARIETTA, Cobb, GA | Pass | State |
| 2026-03-12 | H & B CRUSHING 00380 | KUNA, Ada, ID | Pass | State |
| 2026-03-12 | H & B CRUSHING 00595 | KUNA, Ada, ID | Pending | State |
| 2026-03-12 | H & B CRUSHING 00596 | KUNA, Ada, ID | Pass | State |
| 2026-03-12 | H & B CRUSHING 00597 | KUNA, Ada, ID | Pass | State |
| 2026-03-12 | H & B CRUSHING 00598 | KUNA, Ada, ID | Pass | State |
| 2026-03-12 | H & B CRUSHING 00615 | KUNA, Ada, ID | Pass | State |
| 2026-03-12 | KNAUF INSULATION INCORPORATED — high-priority violation on file | SHELBYVILLE, Shelby, IN | Pass | State |
| 2026-03-12 | NEW GENERATION GAS GATHERING LLC - GROVE HILL BOOSTER STATION | PLEASANT HILL, Sabine, LA | Pass | State |
| 2026-03-12 | NEW GENERATION GAS GATHERING LLC - GROVE HILL BOOSTER STATION | PLEASANT HILL, Sabine, LA | Pass | State |
| 2026-03-12 | NEOGEN CORPORATION | LANSING, Ingham, MI | Pass | State |
| 2026-03-12 | BOISE WHITE PAPER LLC | INTERNATIONAL FALLS, Koochiching, MN | Pass | State |
| 2026-03-12 | SOUTHWEST CLEAN WATER PLANT SPRINGFIELD | SPRINGFIELD, Greene, MO | Pass | State |
| 2026-03-12 | SOUTHWEST CLEAN WATER PLANT SPRINGFIELD | SPRINGFIELD, Greene, MO | Pass | State |
| 2026-03-12 | ENERSYS, INC. — high-priority violation on file | WARRENSBURG, Johnson, MO | Pass | State |
| 2026-03-12 | ENERSYS, INC. — high-priority violation on file | WARRENSBURG, Johnson, MO | Pass | State |
| 2026-03-12 | ENERSYS, INC. — high-priority violation on file | WARRENSBURG, Johnson, MO | Pass | State |
| 2026-03-12 | ENERSYS, INC. — high-priority violation on file | WARRENSBURG, Johnson, MO | Pass | State |
| 2026-03-12 | GULF SOUTH PIPELINE COMPANY LLC, HEIDELBERG COMPRESSOR STATION | HEIDELBERG, Jasper, MS | Pass | State |
| 2026-03-12 | GULF SOUTH PIPELINE COMPANY LLC, HEIDELBERG COMPRESSOR STATION | HEIDELBERG, Jasper, MS | Pass | State |
| 2026-03-12 | GULF SOUTH PIPELINE COMPANY LLC, HEIDELBERG COMPRESSOR STATION | HEIDELBERG, Jasper, MS | Pass | State |
| 2026-03-12 | ALUMINUM DYNAMICS, LLC | COLUMBUS, Lowndes, MS | Pass | State |
| 2026-03-12 | ALUMINUM DYNAMICS, LLC | COLUMBUS, Lowndes, MS | Pass | State |
| 2026-03-12 | CHEMOURS COMPANY - FAYETTEVILLE WORKS | FAYETTEVILLE, Bladen, NC | Pending | State |
| 2026-03-12 | HIGH PLAINS CARBON CAPTURE LLC | COLUMBUS, Platte, NE | Pass | State |
| 2026-03-12 | HF SINCLAIR NAVAJO REFINING LLC (ARTESIA) — high-priority violation on file | ARTESIA, Eddy, NM | Pass | State |
| 2026-03-12 | HF SINCLAIR NAVAJO REFINING LLC (ARTESIA) — high-priority violation on file | ARTESIA, Eddy, NM | Pass | State |
| 2026-03-12 | AZTEC COMPRESSOR STATION — high-priority violation on file | MONUMENT, Lea, NM | Pass | State |
| 2026-03-12 | MESA VERDE WEST CENTRAL GAS LIFT STATION | MALAGA, Lea, NM | Pass | State |
| 2026-03-12 | IRVIN WALL STATE COM NO131H | JAL, Lea, NM | Pass | State |
| 2026-03-12 | SERPENTINE 2 FACILITY 1 | EUNICE, Lea, NM | Pass | State |
| 2026-03-12 | SERPENTINE 2 FACILITY 1 | EUNICE, Lea, NM | Pass | State |
| 2026-03-12 | SERPENTINE 2 FACILITY 1 | EUNICE, Lea, NM | Pass | State |
| 2026-03-12 | PPG ADVANCED SURFACE TECHNOLOGIES, LLC | OHIO, Undetermined, OH | Pass | State |
| 2026-03-12 | PPG ADVANCED SURFACE TECHNOLOGIES, LLC | OHIO, Undetermined, OH | Pass | State |
| 2026-03-12 | MARKWEST HARRISON WEST COMPRESSOR STATION | FREEPORT, Harrison, OH | Pass | State |
| 2026-03-12 | MARKWEST HARRISON WEST COMPRESSOR STATION | FREEPORT, Harrison, OH | Pass | State |
| 2026-03-12 | MARKWEST HARRISON WEST COMPRESSOR STATION | FREEPORT, Harrison, OH | Pass | State |
| 2026-03-12 | MARKWEST HARRISON WEST COMPRESSOR STATION | FREEPORT, Harrison, OH | Pass | State |
| 2026-03-12 | MARKWEST HARRISON WEST COMPRESSOR STATION | FREEPORT, Harrison, OH | Pass | State |
| 2026-03-12 | MARKWEST HARRISON WEST COMPRESSOR STATION | FREEPORT, Harrison, OH | Pass | State |
| 2026-03-12 | MARKWEST HARRISON WEST COMPRESSOR STATION | FREEPORT, Harrison, OH | Pass | State |
| 2026-03-12 | MARKWEST HARRISON WEST COMPRESSOR STATION | FREEPORT, Harrison, OH | Pass | State |
| 2026-03-12 | MARKWEST HARRISON WEST COMPRESSOR STATION | FREEPORT, Harrison, OH | Pass | State |
| 2026-03-12 | MARKWEST HARRISON WEST COMPRESSOR STATION | FREEPORT, Harrison, OH | Pass | State |
| 2026-03-12 | MARKWEST HARRISON WEST COMPRESSOR STATION | FREEPORT, Harrison, OH | Pass | State |
| 2026-03-12 | MARKWEST HARRISON WEST COMPRESSOR STATION | FREEPORT, Harrison, OH | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.