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 | LARAMIE RIVER STATION (BASIN ELECTRIC POWER COOPERATIVE) — high-priority violation on file | WHEATLAND, Platte, WY | Pass | State |
| 2026-03-31 | GREEN RIVER SODA ASH PLANT (AMERICAN SODA LLC) | SWEETWATER COUNTY, Sweetwater, WY | Pass | State |
| 2026-03-31 | GREEN RIVER SODA ASH PLANT (AMERICAN SODA LLC) | SWEETWATER COUNTY, Sweetwater, WY | Pass | State |
| 2026-03-31 | GREEN RIVER SODA ASH PLANT (AMERICAN SODA LLC) | SWEETWATER COUNTY, Sweetwater, WY | Pass | State |
| 2026-03-30 | ET GATHERING & PROCESSING LLC. - KIBLER COMPRESSOR STATION | VAN BUREN, Crawford, AR | Pass | State |
| 2026-03-30 | ET GATHERING & PROCESSING LLC - SOUTH KIBLER COMPRESSOR STATION | KIBLER, Crawford, AR | Pass | State |
| 2026-03-30 | AERA ENERGY LLC — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2026-03-30 | AERA ENERGY LLC — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2026-03-30 | PB LEINER USA | DAVENPORT, Scott, IA | Pass | State |
| 2026-03-30 | CITGO PETROLEUM CORP — high-priority violation on file | LEMONT, Will, IL | Pass | State |
| 2026-03-30 | EXXONMOBIL OIL CORP | LOCKPORT, Will, IL | Pass | State |
| 2026-03-30 | MONTPELIER GENERATING STATION LLC — high-priority violation on file | PONETO, Wells, IN | Pass | State |
| 2026-03-30 | MONTPELIER GENERATING STATION LLC — high-priority violation on file | PONETO, Wells, IN | Pass | State |
| 2026-03-30 | MASSACHUSETTS INSTITUTE OF TECHNOLOGY | CAMBRIDGE, TOWN OF, Middlesex, MA | Pending | State |
| 2026-03-30 | THOMAS HILL ENERGY CENTER - POWER DIVISION | CLIFTON HILL, Randolph, MO | Pass | State |
| 2026-03-30 | MARTIN MARIETTA MATERIALS, INC. - ASHEBORO QUARRY | ASHEBORO, Randolph, NC | Pass | State |
| 2026-03-30 | LOBO COMPRESSOR STATION | LOCO HILLS, Eddy, NM | Pass | State |
| 2026-03-30 | DIMENSIONS 6 GAS LIFT COMPRESSOR STATION | MALAGA, Eddy, NM | Pass | State |
| 2026-03-30 | DIMENSIONS 6 GAS LIFT COMPRESSOR STATION | MALAGA, Eddy, NM | Pass | State |
| 2026-03-30 | COACH JOE FED TB | LOCO HILLS, Eddy, NM | Pass | State |
| 2026-03-30 | BENT TREE 9 CTB 2 | LA HUERTA, Eddy, NM | Pass | State |
| 2026-03-30 | RICO COMPRESSOR STATION | MALAGA, Lea, NM | Pass | State |
| 2026-03-30 | RICO COMPRESSOR STATION | MALAGA, Lea, NM | Pass | State |
| 2026-03-30 | MARWARI 28 CTB 2 | MALAGA, Lea, NM | Pass | State |
| 2026-03-30 | GATO GRANDE 16 CTB 1 | MALAGA, Lea, NM | Pass | State |
| 2026-03-30 | STRANGER 34 CTB 1 | JAL, Lea, NM | Pass | State |
| 2026-03-30 | LEA COUNTY ELECTRIC COOPERATIVE POWER PLANT | LOVINGTON, Lea, NM | Pass | State |
| 2026-03-30 | LEA COUNTY ELECTRIC COOPERATIVE POWER PLANT | LOVINGTON, Lea, NM | Pass | State |
| 2026-03-30 | LEA COUNTY ELECTRIC COOPERATIVE POWER PLANT | LOVINGTON, Lea, NM | Pass | State |
| 2026-03-30 | LEA COUNTY ELECTRIC COOPERATIVE POWER PLANT | LOVINGTON, Lea, NM | Pass | State |
| 2026-03-30 | LEA COUNTY ELECTRIC COOPERATIVE POWER PLANT | LOVINGTON, Lea, NM | Pass | State |
| 2026-03-30 | LEA COUNTY ELECTRIC COOPERATIVE POWER PLANT | LOVINGTON, Lea, NM | Pass | State |
| 2026-03-30 | LAUREL MTN MIDSTREAM OPR LLC/DUNBAR COMP STA | DUNBAR, Fayette, PA | Pass | State |
| 2026-03-30 | RWE HOLDING CO/WEST PITTSBURG PLT — high-priority violation on file | NEW CASTLE, Lawrence, PA | Pass | State |
| 2026-03-30 | HIGH PLAINS PROCESSING, LLC, A DELAWARE LIMITED LIABILITY | MITCHELL, Davison, SD | Pass | State |
| 2026-03-29 | LEA COUNTY ELECTRIC COOPERATIVE POWER PLANT | LOVINGTON, Lea, NM | Pass | State |
| 2026-03-29 | LEA COUNTY ELECTRIC COOPERATIVE POWER PLANT | LOVINGTON, Lea, NM | Pass | State |
| 2026-03-29 | LEA COUNTY ELECTRIC COOPERATIVE POWER PLANT | LOVINGTON, Lea, NM | Pass | State |
| 2026-03-29 | LEA COUNTY ELECTRIC COOPERATIVE POWER PLANT | LOVINGTON, Lea, NM | Pass | State |
| 2026-03-28 | MACY J COMPRESSOR STATION | MALAGA, Eddy, NM | Pass | State |
| 2026-03-28 | COTTON DRAW UNIT 25 CTB 5 & COTTON DRAW 25 CTB 4 | MALAGA, Eddy, NM | Pass | State |
| 2026-03-27 | KRONOSPAN USA — high-priority violation on file | EASTABOGA, Calhoun, AL | Pass | State |
| 2026-03-27 | KRONOSPAN USA — high-priority violation on file | EASTABOGA, Calhoun, AL | Pass | State |
| 2026-03-27 | POWERSOUTH ENERGY COOPERATIVE INC | MCINTOSH, Washington, AL | Pass | State |
| 2026-03-27 | LA CO. SANITATION DIST | CARSON, Los Angeles, CA | Pass | Local |
| 2026-03-27 | ARMSTRONG WORLD INDUSTRIES, INC. | PENSACOLA, Escambia, FL | Pass | State |
| 2026-03-27 | MECO - MAALAEA | MAALAEA, Maui, HI | Pass | State |
| 2026-03-27 | HOLCIM (US) INC | GRAND CHAIN, Massac, IL | Pass | State |
| 2026-03-27 | ARAPAHOE PARK COMPRESSOR STATION | WHITES CITY, Eddy, NM | Pass | State |
| 2026-03-27 | WINGMAN AIRBOSS BATTERY | CARLSBAD, Eddy, NM | Pass | State |
| 2026-03-27 | DEVON - FULLY LOADED 12 CTB 2 | MALAGA, Eddy, NM | Pass | State |
| 2026-03-27 | SALADO DRAW COMPRESSOR STATION | JAL, Lea, NM | Pass | State |
| 2026-03-27 | ROCCO COMPRESSOR STATION | MALAGA, Lea, NM | Pass | State |
| 2026-03-27 | NINA CORTELL SOUTH TB | LOVING, Lea, NM | Pass | State |
| 2026-03-27 | LHOIST NORTH AMERICA OF ARIZONA - APEX PLANT — high-priority violation on file | LAS VEGAS, Clark, NV | Pass | Local |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | NORTHSTAR BLUESCOPE STEEL, LLC | DELTA, Fulton, OH | Pass | State |
| 2026-03-27 | COLUMBIA GAS TRANSMISSION -D74 SOUTH MUDDY CREEK COMPRESSION | OAK HARBOR, Ottawa, OH | Pass | State |
| 2026-03-27 | COLUMBIA GAS TRANSMISSION -D74 SOUTH MUDDY CREEK COMPRESSION | OAK HARBOR, Ottawa, OH | Pass | State |
| 2026-03-27 | COLUMBIA GAS TRANSMISSION -D74 SOUTH MUDDY CREEK COMPRESSION | OAK HARBOR, Ottawa, OH | Pass | State |
| 2026-03-27 | SGL CARBON CORP/ST MARYS PLT | SAINT MARYS, Elk, PA | Pending | State |
| 2026-03-27 | PIN OAK MIDSTREAM LLC/HURTT COMP STA | NEW WILMINGTON, Mercer, PA | Pass | State |
| 2026-03-27 | MARKWEST LIBERTY MIDSTREAM/SMITH COMP STA | BURGETTSTOWN, Washington, PA | Pass | State |
| 2026-03-27 | NFG MIDSTREAM CLERMONT LLC/RICH VALLEY COMP STA | EMPORIUM, Cameron, PA | Pass | State |
| 2026-03-27 | MCKINLEY PAPER AND PACKAGING COMPANY — high-priority violation on file | COMBINED LOCKS, Ozaukee, WI | Pass | State |
| 2026-03-26 | HYUNDAI MOTOR MANUFACTURING ALABAMA LLC. | MONTGOMERY, Montgomery, AL | Pass | State |
| 2026-03-26 | REGIONS OPERATIONS CENTER | BIRMINGHAM, Jefferson, AL | Pass | Local |
| 2026-03-26 | CALPORTLAND - RILLITO CEMENT PLANT | MARANA, Pima, AZ | Pass | State |
| 2026-03-26 | BAGDAD MINE | BAGDAD, Yavapai, AZ | Pass | State |
| 2026-03-26 | CENTRAL VALLEY MEAT CO | HANFORD, Kings, CA | Pass | Local |
| 2026-03-26 | CENTRAL VALLEY MEAT CO | HANFORD, Kings, CA | Pass | Local |
| 2026-03-26 | CENTRAL VALLEY MEAT CO | HANFORD, Kings, CA | Pass | Local |
| 2026-03-26 | CENTRAL VALLEY MEAT CO | HANFORD, Kings, CA | Pass | Local |
| 2026-03-26 | AMRIZE PORTLAND PLANT — high-priority violation on file | FLORENCE 3.8 MI. E OF, Fremont, CO | Pass | State |
| 2026-03-26 | LEPRINO FOODS COMPANY - GREELEY PLANT | GREELEY, Weld, CO | N/A | State |
| 2026-03-26 | WES DJ FT LUPTON/PLATTE VALLEY/LANCASTER — high-priority violation on file | FORT LUPTON, Weld, CO | Pass | State |
| 2026-03-26 | MILLIKEN & CO. DBA SIVANCE, LLC | GAINESVILLE, Alachua, FL | Pass | State |
| 2026-03-26 | MILLIKEN & CO. DBA SIVANCE, LLC | GAINESVILLE, Alachua, FL | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.