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 |
|---|---|---|---|---|
| 2026-04-02 | CEMEX SOUTHEAST, LLC | CLINCHFIELD, Houston, GA | Pass | State |
| 2026-04-02 | CEMEX SOUTHEAST, LLC | CLINCHFIELD, Houston, GA | Pass | State |
| 2026-04-02 | CEMEX SOUTHEAST, LLC | CLINCHFIELD, Houston, GA | Pass | State |
| 2026-04-02 | FPL FOOD, LLC — high-priority violation on file | AUGUSTA, Richmond, GA | Fail | State |
| 2026-04-02 | FPL FOOD, LLC — high-priority violation on file | AUGUSTA, Richmond, GA | Pass | State |
| 2026-04-02 | PRATT PAPER (GA), LLC — high-priority violation on file | CONYERS, Rockdale, GA | Pass | State |
| 2026-04-02 | MICROSOFT CORPORATION - WILLOW CREEK/GINGER EAST DATA | DES MOINES, Polk, IA | Pending | Local |
| 2026-04-02 | MICROSOFT CORPORATION - WILLOW CREEK/GINGER EAST DATA | DES MOINES, Polk, IA | Pending | Local |
| 2026-04-02 | J R SIMPLOT COMPANY-DON SIDING POCATELLO — high-priority violation on file | POCATELLO, Power, ID | Pass | State |
| 2026-04-02 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-02 | GRAIN PROCESSING CORPORATION — high-priority violation on file | WASHINGTON, Daviess, IN | Pass | State |
| 2026-04-02 | GRAIN PROCESSING CORPORATION — high-priority violation on file | WASHINGTON, Daviess, IN | Pass | State |
| 2026-04-02 | GRAIN PROCESSING CORPORATION — high-priority violation on file | WASHINGTON, Daviess, IN | Pass | State |
| 2026-04-02 | BUCKEYE TERMINALS LLC EAST CHICAGO TERMINAL | EAST CHICAGO, Lake, IN | Pass | State |
| 2026-04-02 | MPLX TERMINALS LLC - INDIANAPOLIS TERMINAL | INDIANAPOLIS, Marion, IN | Pass | State |
| 2026-04-02 | MPLX TERMINALS LLC - INDIANAPOLIS TERMINAL | INDIANAPOLIS, Marion, IN | Pass | State |
| 2026-04-02 | CARDINAL ETHANOL LLC — high-priority violation on file | UNION CITY, Randolph, IN | Pass | State |
| 2026-04-02 | WASTE NO ENERGY LLC | MONTICELLO, White, IN | Pass | State |
| 2026-04-02 | WASTE NO ENERGY LLC | MONTICELLO, White, IN | Pass | State |
| 2026-04-02 | WASTE NO ENERGY LLC | MONTICELLO, White, IN | Pass | State |
| 2026-04-02 | MAGNA MIRRORS NORTH AMERICA | NEWAYGO, Newaygo, MI | Pass | State |
| 2026-04-02 | JBS WORTHINGTON MN | WORTHINGTON, Nobles, MN | Pass | State |
| 2026-04-02 | CERTAINTEED LLC - OXFORD FACILITY | OXFORD, Granville, NC | Pass | State |
| 2026-04-02 | ENVIVA HAMLET | HAMLET, Richmond, NC | Pending | State |
| 2026-04-02 | BLACK RIVER COMPRESSOR STATION | MALAGA, Chaves, NM | Pass | State |
| 2026-04-02 | BLACK RIVER COMPRESSOR STATION | MALAGA, Chaves, NM | Pass | State |
| 2026-04-02 | CEDAR CANYON 28 COMPRESSOR STATION | MALAGA, Eddy, NM | Pass | State |
| 2026-04-02 | CEDAR CANYON 28 COMPRESSOR STATION | MALAGA, Eddy, NM | Pass | State |
| 2026-04-02 | CEDAR CANYON 28 COMPRESSOR STATION | MALAGA, Eddy, NM | Pass | State |
| 2026-04-02 | BENT TREE 8 CTB 1 | LA HUERTA, Eddy, NM | Pass | State |
| 2026-04-02 | BENT TREE 8 CTB 1 | LA HUERTA, Eddy, NM | Pass | State |
| 2026-04-02 | HORNED FROG COMPRESSOR STATION | JAL, Lea, NM | Pass | State |
| 2026-04-02 | HORNED FROG COMPRESSOR STATION | JAL, Lea, NM | Pass | State |
| 2026-04-02 | TRISTE DRAW 36-25 CTB | MALAGA, Lea, NM | Pass | State |
| 2026-04-02 | CHARLES LING NORTH TB | JAL, Lea, NM | Pass | State |
| 2026-04-02 | EOG RESOURCES, INC - INDIGO CTB | MALVERN, Carroll, OH | Pass | State |
| 2026-04-02 | EOG RESOURCES, INC - INDIGO CTB | MALVERN, Carroll, OH | Pass | State |
| 2026-04-02 | EOG RESOURCES, INC - INDIGO CTB | MALVERN, Carroll, OH | Pass | State |
| 2026-04-02 | REGENCY MARCELLUS GAS GATHERING/CANOE RUN COMP STA | SALLADASBURG, Lycoming, PA | Pass | State |
| 2026-04-02 | NFG MIDSTREAM COVINGTON LLC/NETTERMAN COMP STA | WELLSBORO, Tioga, PA | Pass | State |
| 2026-04-02 | WILLIAMS FIELD SVC CO LLC/CENTRAL COMP STA | MONTROSE, Susquehanna, PA | Pass | State |
| 2026-04-02 | LARUE, C PAD 2 — high-priority violation on file | MONTROSE, Susquehanna, PA | Pass | State |
| 2026-04-02 | BUCKEYE TERMINALS, LLC/INDIANOLA | INDIANOLA, Allegheny, PA | Pass | Local |
| 2026-04-02 | ALLEGHENY CNTY SANI AUTH/ALLEGHENY CNTY | PITTSBURGH, Allegheny, PA | Pass | Local |
| 2026-04-02 | KIMBERLY-CLARK PALMETTO — high-priority violation on file | BEECH ISLAND, Aiken, SC | Pass | State |
| 2026-04-02 | CENTURY ALUMINUM OF SOUTH CAROLINA INC — high-priority violation on file | GOOSE CREEK, Berkeley, SC | Pending | State |
| 2026-04-02 | MCMINNVILLE ELECTRIC SYSTEM | MCMINNVILLE, Warren, TN | Pass | State |
| 2026-04-02 | US NAVY - NAVAL STATION NORFOLK | NORFOLK, Norfolk (city), VA | Pass | State |
| 2026-04-02 | US NAVY - NAVAL STATION NORFOLK | NORFOLK, Norfolk (city), VA | Pass | State |
| 2026-04-02 | WISCONSIN ALUMINUM FOUNDRY — high-priority violation on file | MANITOWOC, Manitowoc, WI | Fail | State |
| 2026-04-02 | WAUPACA FOUNDRY, INC.-PLANT 4 | MARINETTE, Marinette, WI | Pass | State |
| 2026-04-02 | WAUPACA FOUNDRY INC - PLANT 1 | WAUPACA, Waushara, WI | Pass | State |
| 2026-04-02 | EQM GATHERING OPCO, LLC, SATURN STATION | CENTRAL STATION, Doddridge, WV | Pass | State |
| 2026-04-02 | CNX MIDSTREAM OPERATING COMPANY LLC, DRY RIDGE STATION | CAMERON, Marshall, WV | Pass | State |
| 2026-04-02 | LOST CABIN GAS PLANT (CONTANGO RESOURCES, LLC.) — high-priority violation on file | LOST CABIN, Fremont, WY | Pass | State |
| 2026-04-02 | GREEN RIVER SODA ASH PLANT (AMERICAN SODA LLC) | SWEETWATER COUNTY, Sweetwater, WY | Pass | State |
| 2026-04-02 | GREEN RIVER SODA ASH PLANT (AMERICAN SODA LLC) | SWEETWATER COUNTY, Sweetwater, WY | Pass | State |
| 2026-04-01 | DEMOPOLIS PELLETS, LLC | DEMOPOLIS, Marengo, AL | Pass | State |
| 2026-04-01 | ENABLE GAS TRANSMISSION, LLC - WALKER COMPRESSOR STATION | CECIL, Franklin, AR | Pass | State |
| 2026-04-01 | ENABLE GAS TRANSMISSION, LLC - WALKER COMPRESSOR STATION | CECIL, Franklin, AR | Pass | State |
| 2026-04-01 | APS WEST PHX POWER PLANT | MARICOPA COUNTY, Maricopa, AZ | Pass | Local |
| 2026-04-01 | IVANPAH I, II, III | IVANPAH, San Bernardino, CA | Pass | Local |
| 2026-04-01 | IVANPAH I, II, III | IVANPAH, San Bernardino, CA | Pass | Local |
| 2026-04-01 | IVANPAH I, II, III | IVANPAH, San Bernardino, CA | Pass | Local |
| 2026-04-01 | IROQUOIS PIPELINE OPERATING COMPANY - BROOKFIELD COMPRESSOR STATION | BROOKFIELD, Fairfield, CT | Pass | State |
| 2026-04-01 | LUVATA WATERBURY, INC. | WATERBURY, New Haven, CT | Pass | State |
| 2026-04-01 | ALGONQUIN GAS TRANSMISSION LLC - OXFORD COMPRESSOR STATION | OXFORD, New Haven, CT | Pass | State |
| 2026-04-01 | MIAMI-DADE WATER AND SEWER DEPARTMENT | MIAMI, Miami-Dade, FL | Pass | State |
| 2026-04-01 | MIAMI-DADE WATER AND SEWER DEPARTMENT | MIAMI, Miami-Dade, FL | Pass | State |
| 2026-04-01 | MIAMI-DADE WATER AND SEWER DEPARTMENT | MIAMI, Miami-Dade, FL | Pass | State |
| 2026-04-01 | ASCEND PERFORMANCE MATERIALS OPERATIONS — high-priority violation on file | CANTONMENT, Escambia, FL | Pass | State |
| 2026-04-01 | INTERNATIONAL PAPER COMPANY | CANTONMENT, Escambia, FL | Pass | State |
| 2026-04-01 | INTERNATIONAL PAPER COMPANY | CANTONMENT, Escambia, FL | Pass | State |
| 2026-04-01 | INTERNATIONAL PAPER COMPANY | CANTONMENT, Escambia, FL | Pass | State |
| 2026-04-01 | WHITE SPRINGS AGRICULTURAL CHEMICALS,INC | WHITE SPRINGS, Hamilton, FL | Pass | State |
| 2026-04-01 | IPL � MARSHALLTOWN GENERATING STATION | MARSHALLTOWN, Marshall, IA | Pass | State |
| 2026-04-01 | STRAWBERRY POINT UTILITIES — high-priority violation on file | STRAWBERRY POINT, Clayton, IA | Pass | State |
| 2026-04-01 | STRAWBERRY POINT UTILITIES — high-priority violation on file | STRAWBERRY POINT, Clayton, IA | Pass | State |
| 2026-04-01 | PEOPLES GAS LIGHT & COKE CO | FISHER, Champaign, IL | Pass | State |
| 2026-04-01 | PEOPLES GAS LIGHT & COKE CO | FISHER, Champaign, IL | Pass | State |
| 2026-04-01 | NICOR GAS | TROY GROVE, La Salle, IL | Pass | State |
| 2026-04-01 | NICOR GAS | TROY GROVE, La Salle, IL | Pass | State |
| 2026-04-01 | NICOR GAS | TROY GROVE, La Salle, IL | Pass | State |
| 2026-04-01 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-01 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-01 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-01 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-01 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-01 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-01 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-01 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-01 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-01 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-01 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-01 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-01 | HILLSBORO ENERGY LLC | HILLSBORO, Montgomery, IL | Pass | State |
| 2026-04-01 | ANR PIPELINE CO | JOLIET, Will, IL | Pass | State |
| 2026-04-01 | WILLIAMSON ENERGY LLC | JOHNSTON CITY, Williamson, IL | Pass | State |
| 2026-04-01 | WILLIAMSON ENERGY LLC | JOHNSTON CITY, Williamson, IL | Pass | State |
| 2026-04-01 | WILLIAMSON ENERGY LLC | JOHNSTON CITY, Williamson, IL | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.