EPA Air · stack tests by state and year
Air-emissions stack tests in Pennsylvania, 2025
- 951Stack tests
A stack test measures what a source actually emits, at the stack, against the limit in its permit. Every stack test below was recorded against a source in Pennsylvania during 2025; one facility can appear more than once, because this is a record of what happened rather than a list of places.
Counties in Pennsylvania, 2025
- Susquehanna County 159
- Bradford County 63
- Washington County 59
- Lycoming County 51
- Greene County 47
- Tioga County 45
- Philadelphia County 41
- Butler County 30
- Westmoreland County 27
- Lancaster County 23
- Berks County 22
- Wyoming County 22
- Bucks County 21
- York County 19
- Mercer County 18
- Allegheny County 17
- Armstrong County 17
- Elk County 17
- Northampton County 15
- Montgomery County 15
- Delaware County 14
- Schuylkill County 13
- Luzerne County 12
- Potter County 11
- Clinton County 11
- Beaver County 10
- Fayette County 10
- Dauphin County 10
- Indiana County 9
- McKean County 9
- Centre County 9
- Chester County 8
- Cambria County 8
- Bedford County 8
- Venango County 7
- Jefferson County 6
- Columbia County 6
- Sullivan County 5
- Warren County 5
- Franklin County 5
- Clarion County 5
- Clearfield County 4
- Lawrence County 4
- Juniata County 3
- Montour County 3
- Carbon County 3
- Lehigh County 3
Pennsylvania, other years
Air-emissions stack tests recorded in Pennsylvania, 2025
| Date | Facility | Where | Kind | Agency |
|---|---|---|---|---|
| 2025-06-24 | WILLIAMS FIELD SVC CO LLC/NORTHEAST COMP STA | HALLSTEAD, Susquehanna, PA | Pass | State |
| 2025-06-24 | GREYLOCK PROD LLC/ANSONVILLE COMP STA | NEW MILLPORT, Clearfield, PA | Pass | State |
| 2025-06-24 | EXPAND OPERATING LLC/ADAMS WYO PAD | LACEYVILLE, Wyoming, PA | Pass | State |
| 2025-06-24 | SQUIER, R. PAD 1 — high-priority violation on file | KINGSLEY, Susquehanna, PA | Pass | State |
| 2025-06-24 | LAUFFER, J. PAD 1 — high-priority violation on file | SPRINGVILLE, Susquehanna, PA | Pass | State |
| 2025-06-23 | EQT PROD CO/MOJO COMPRESSOR UNIT | WASHINGTON, Washington, PA | Pass | State |
| 2025-06-23 | JKLM ENERGY LLC/HEADWATERS 145 WELL PAD | ULYSSES, Potter, PA | Pass | State |
| 2025-06-20 | LATROBE SPECIALTY METALS/ A CARPENTER CO | LATROBE, Westmoreland, PA | Pass | State |
| 2025-06-20 | HEIDELBERG MATERIALS US CEMENT LLC/NAZARETH | NAZARETH, Northampton, PA | Pass | State |
| 2025-06-20 | GANS ENERGY LLC/GANS POWER STA | GANS, Fayette, PA | Pass | State |
| 2025-06-20 | HAMILTON LIBERTY LLC/HAMILTON LIBERTY LLC — high-priority violation on file | WYSOX, Bradford, PA | Pass | State |
| 2025-06-19 | HEIDELBERG MATERIALS US CEMENT LLC/NAZARETH | NAZARETH, Northampton, PA | Pass | State |
| 2025-06-19 | REGENCY MARCELLUS GAS GATHERING LLC/ROUPP COMP STA | MIFFLIN, Lycoming, PA | Pass | State |
| 2025-06-18 | PEOPLES NATURAL GAS CO LLC/VALLEY STA | YATESBORO, Armstrong, PA | Pending | State |
| 2025-06-18 | COLUMBIA GAS TRANS LLC/ARTEMAS COMP STA | ARTEMAS, Bedford, PA | Pass | State |
| 2025-06-18 | REWORLD DELAWARE VALLEY LP/DELAWARE VALLEY RES REC — high-priority violation on file | CHESTER, Delaware, PA | Pass | State |
| 2025-06-18 | EAST PENN MFG CO INC/SMELTER PLT | LYONS, Berks, PA | Pass | State |
| 2025-06-18 | EQUITRANS LP/JEFFERSON COMP STA | LIPPINCOTT, Greene, PA | Pass | State |
| 2025-06-18 | EXPAND OPERATING LLC/N-24 BUCKHORN WELL PAD | MONTROSE, Susquehanna, PA | Pass | State |
| 2025-06-17 | PEOPLES NATURAL GAS CO LLC/VALLEY STA | YATESBORO, Armstrong, PA | Pass | State |
| 2025-06-17 | CNX MIDSTREAM OPR CO LLC /MORRIS DEHY STATION | GRAYSVILLE, Greene, PA | Pass | State |
| 2025-06-17 | EQM GATHERING OPCO LLC/EUROPA COMP STA | CENTER, Greene, PA | Pass | State |
| 2025-06-16 | EXPAND OPERATING LLC/RU-06 FLOHS PAD | NEW MILFORD, Susquehanna, PA | Pass | State |
| 2025-06-14 | BIRDSBORO POWER LLC/BIRDSBORO POWER PROJECT | BIRDSBORO, Berks, PA | Pass | State |
| 2025-06-13 | HAMILTON PATRIOT LLC/HAMILTON PATRIOT GENERATION PLANT — high-priority violation on file | MONTGOMERY, Lycoming, PA | Pass | State |
| 2025-06-12 | MERCK SHARP & DOHME LLC/WEST PT | WEST POINT, Montgomery, PA | Pass | State |
| 2025-06-12 | INTER POWER AHLCON LP/COLVER POWER PROJ — high-priority violation on file | COLVER, Cambria, PA | Pass | State |
| 2025-06-12 | ENERGY TRANSFER MKT & TERM LP/MALVERN TERM | MALVERN, Chester, PA | Pass | State |
| 2025-06-12 | ENERGY TRANSFER MKT & TERM LP/MALVERN TERM | MALVERN, Chester, PA | Pass | State |
| 2025-06-12 | UGI TEXAS CREEK LLC/THOMAS 808 FAC | ELK TOWNSHIP, Tioga, PA | Pass | State |
| 2025-06-12 | UGI TEXAS CREEK LLC/PIERSON 810 COMP STA | GAINES, Tioga, PA | Pass | State |
| 2025-06-12 | REGENCY MARCELLUS GAS GATHERING LLC/QUAKER STATE RD COMP STA | MONTOURSVILLE, Lycoming, PA | Pass | State |
| 2025-06-12 | ALLEGHENY ENERGY SUPPLY/SPRINGDALE | PITTSBURGH, Allegheny, PA | Pass | Local |
| 2025-06-11 | INTER POWER AHLCON LP/COLVER POWER PROJ — high-priority violation on file | COLVER, Cambria, PA | Pass | State |
| 2025-06-11 | ENERGY TRANSFER MKT & TERM LP/TWIN OAKS TERM | ASTON, Delaware, PA | Pass | State |
| 2025-06-11 | PEOPLES NATURAL GAS CO LLC/BELKNAP COMP STA | DAYTON, Armstrong, PA | Pass | State |
| 2025-06-11 | UGI TEXAS CREEK LLC/CLEGG COMP STA | TROUT RUN, Lycoming, PA | Pass | State |
| 2025-06-11 | HAMILTON PATRIOT LLC/HAMILTON PATRIOT GENERATION PLANT — high-priority violation on file | MONTGOMERY, Lycoming, PA | Pass | State |
| 2025-06-11 | UGI TEXAS CREEK LLC/JACKSON COMP STA | ROARING BRANCH, Tioga, PA | Pass | State |
| 2025-06-11 | NFG MIDSTREAM TROUT RUN LLC/TROUT RUN MTN COMP STA | TROUT RUN, Lycoming, PA | Pass | State |
| 2025-06-11 | XPRESS NATURAL GAS LLC/MONTROSE — high-priority violation on file | MONTROSE, Susquehanna, PA | Pass | State |
| 2025-06-11 | USS/CLAIRTON WORKS — high-priority violation on file | CLAIRTON, Allegheny, PA | Pass | Local |
| 2025-06-11 | ALLEGHENY ENERGY SUPPLY/SPRINGDALE | PITTSBURGH, Allegheny, PA | Pending | Local |
| 2025-06-10 | CONSOL PA COAL CO LLC/BAILEY PREP PLT — high-priority violation on file | WEST FINLEY, Greene, PA | Pass | State |
| 2025-06-10 | ENERGY TRANSFER MKT & TERM LP/TWIN OAKS TERM | ASTON, Delaware, PA | Pass | State |
| 2025-06-10 | NFG MIDSTREAM COVINGTON LLC/SHAW COMP STA | MAINESBURG, Tioga, PA | Pending | State |
| 2025-06-10 | EQM GATHERING OPCO LLC/CALLISTO COMP STA | SYCAMORE, Greene, PA | Pass | State |
| 2025-06-10 | EQM GATHERING OPCO LLC/CALLISTO COMP STA | SYCAMORE, Greene, PA | Pass | State |
| 2025-06-10 | FRESHPET INC/BETHLEHEM | BETHLEHEM, Northampton, PA | Pass | State |
| 2025-06-10 | DIETZ & WATSON INC/PHILA | PHILADELPHIA, Philadelphia, PA | Pass | Local |
| 2025-06-06 | NLMK PENNSYLVANIA LLC/FARRELL PLT — high-priority violation on file | FARRELL, Mercer, PA | Pass | State |
| 2025-06-06 | HIGHWAY MATERIALS INC/PLYMOUTH MTG ASPHALT PLT | PLYMOUTH MEETING, Montgomery, PA | Pass | State |
| 2025-06-06 | STARBUCKS COFFEE CO/YORK ROASTING PLT | YORK, York, PA | Pass | State |
| 2025-06-05 | PA STATE SYS OF HIGHER ED/INDIANA UNIV | INDIANA, Indiana, PA | Pass | State |
| 2025-06-05 | UGI TEXAS CREEK LLC/LOVELL COMP STA | ROARING BRANCH, Tioga, PA | Pass | State |
| 2025-06-05 | BLUESTONE PIPELINE/CDP#1-A | NEW MILFORD, Susquehanna, PA | Pass | State |
| 2025-06-05 | USS/CLAIRTON WORKS — high-priority violation on file | CLAIRTON, Allegheny, PA | Pass | Local |
| 2025-06-04 | LATROBE SPECIALTY METALS/ A CARPENTER CO | LATROBE, Westmoreland, PA | Pass | State |
| 2025-06-04 | UGI TEXAS CREEK LLC/LOVELL COMP STA | ROARING BRANCH, Tioga, PA | Pass | State |
| 2025-06-04 | EXPAND OPERATING LLC/NR02 ENDLESS MOUNTAIN WELLPAD | MONTROSE, Susquehanna, PA | Pass | State |
| 2025-06-04 | NORTHEAST WPCP/PHILA — high-priority violation on file | PHILADELPHIA, Philadelphia, PA | Pass | Local |
| 2025-06-04 | NORTHEAST WPCP/PHILA — high-priority violation on file | PHILADELPHIA, Philadelphia, PA | Pass | Local |
| 2025-06-03 | GREATER HAZLETON JT SEW AUTH/WEST HAZLETON STP — high-priority violation on file | WEST HAZLETON, Luzerne, PA | Fail | State |
| 2025-06-03 | JESSOP STEEL LLC/WASHINGTON PLT | WASHINGTON, Washington, PA | Pass | State |
| 2025-06-03 | CONSOL PA COAL CO LLC/BAILEY PREP PLT — high-priority violation on file | WEST FINLEY, Greene, PA | Pass | State |
| 2025-06-03 | UGI TEXAS CREEK LLC/YAGGIE COMP STA | ROARING BRANCH, Tioga, PA | Pass | State |
| 2025-06-03 | EQM GATHERING OPCO LLC/PISCES COMP STA | CLAYSVILLE, Washington, PA | Pass | State |
| 2025-06-03 | ARDEX LP/ALIQUIPPA | ALIQUIPPA, Beaver, PA | Pass | State |
| 2025-06-03 | NORTHEAST WPCP/PHILA — high-priority violation on file | PHILADELPHIA, Philadelphia, PA | Pass | Local |
| 2025-06-02 | REGENCY MARCELLUS GAS GATHERING LLC/LONE WALNUT COMP STA | JERSEY SHORE, Lycoming, PA | Pass | State |
| 2025-06-02 | UGI TEXAS CREEK LLC/TRIMBLE COMP STA | ROARING BRANCH, Tioga, PA | Pass | State |
| 2025-06-02 | UGI TEXAS CREEK LLC/CASTLE COMP STA | CANTON, Bradford, PA | Pass | State |
| 2025-05-30 | ARMSTRONG CEMENT & SUPPLY/WINFIELD — high-priority violation on file | CABOT, Butler, PA | Pass | State |
| 2025-05-30 | WALTER R EARLE ASPHALT PLT/MORRISVILLE — high-priority violation on file | MORRISVILLE, Bucks, PA | Pending | State |
| 2025-05-30 | NEXTERA RENEWABLE FUELS LLC/LYCO LANDFILL LFGTE PLT | MONTGOMERY, Lycoming, PA | Pass | State |
| 2025-05-30 | MTN GATHERING LLC/FORWARD COMP STA | RENFREW, Butler, PA | Pass | State |
| 2025-05-29 | HEIDELBERG MATERIALS US CEMENT LLC/EVANSVILLE CEMENT PLT & Q — high-priority violation on file | FLEETWOOD, Berks, PA | Pass | State |
| 2025-05-29 | BEFESA ZINC US INC./PALMERTON — high-priority violation on file | PALMERTON, Carbon, PA | Pass | State |
| 2025-05-29 | MARTINS FAMOUS PASTRY SHOPPE/CHAMBERSBURG | CHAMBERSBURG, Franklin, PA | Pass | State |
| 2025-05-29 | GREYLOCK MIDSTREAM LLC/VERES COMP STA | WAYNESBURG, Greene, PA | Pass | State |
| 2025-05-29 | ARIA ENERGY EAST LLC | BETHLEHEM, Northampton, PA | Pass | State |
| 2025-05-28 | COLUMBIA GAS TRANS CORP/GREENCASTLE | GREENCASTLE, Franklin, PA | Pass | State |
| 2025-05-28 | LANCASTER CNTY SWMA/SUSQ RESOURCE MGMT COMPLEX — high-priority violation on file | HARRISBURG, Dauphin, PA | Fail | State |
| 2025-05-28 | WASTE MGMT PA/TULLYTOWN RES REC FAC | TULLYTOWN, Bucks, PA | Pass | State |
| 2025-05-28 | EQT ARTEMIS MIDSTREAM LLC/ROGERS COMP STA — high-priority violation on file | NEW KENSINGTON, Westmoreland, PA | Pass | State |
| 2025-05-28 | CHAMBERS DEV CO INC/MONROEVILLE | PITTSBURGH, Allegheny, PA | Pass | Local |
| 2025-05-27 | MARKWEST LIBERTY BLUESTONE LLC/SARSEN GAS PROC PLT | EVANS CITY, Butler, PA | Pass | State |
| 2025-05-23 | CCL CONTAINER/ADVANCED MONOBLOC AEROSOL DIV — high-priority violation on file | HERMITAGE, Mercer, PA | Pass | State |
| 2025-05-23 | CONSTELLATION GENERATION CO/SCHUYLKILL STA | PHILADELPHIA, Philadelphia, PA | Pass | Local |
| 2025-05-22 | GUTHRIE ROBERT PACKER/SAYRE | SAYRE, Bradford, PA | Pending | State |
| 2025-05-22 | HUMMEL STA LLC/SUNBURY NAT GAS PLT | SHAMOKIN DAM, Snyder, PA | Pass | State |
| 2025-05-22 | SNYDER BROS INC/WHITE COMP STA | KITTANNING, Armstrong, PA | Pass | State |
| 2025-05-22 | EXPAND OPER LLC/GU-K CAMPBELL ERCOLE WELL PAD | STEVENSVILLE, Bradford, PA | Pass | State |
| 2025-05-22 | CONSTELLATION GENERATION CO/SCHUYLKILL STA | PHILADELPHIA, Philadelphia, PA | Pass | Local |
| 2025-05-21 | KEYSTONE PORTLAND CEMENT/EAST ALLEN — high-priority violation on file | BATH, Northampton, PA | Pass | State |
| 2025-05-21 | RW GATHERING LLC/SALEM COMP STA | DERRY, Westmoreland, PA | Pass | State |
| 2025-05-21 | APPALACHIA MIDSTREAM SVC LLC/WILMOT COMP STA | WYALUSING, Bradford, PA | Pass | State |
| 2025-05-21 | REGENCY MARCELLUS GAS GATHERING LLC/SEVERCOOL STA | FORKSTON, Wyoming, PA | Pass | State |
| 2025-05-21 | EXPAND OPERATING LLC/VALENTINE CPF 1 | CLIFFORD, Susquehanna, PA | Pass | State |
| 2025-05-21 | EXPAND OPERATING LLC/VALENTINE CPF 1 | CLIFFORD, Susquehanna, PA | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.