EPA Air · stack tests by county and year
Air-emissions stack tests in Mercer County, Pennsylvania, 2026
- 12Stack tests
A stack test measures what a source actually emits, at the stack, against the limit in its permit. Each row below is one stack test recorded against a source in Mercer County, Pennsylvania during 2026. A facility can appear several times: this is the year’s record of what happened, not a list of places. The sources themselves are on the Mercer County facility page.
Mercer County, Pennsylvania, 2026
- Inspections 64
Air-emissions stack tests in Mercer County, other years
What stands out
- Stack tests in Mercer County, Pennsylvania, fell from 19 in 2025, the previous year on file, to 12 in 2026.
- The county’s file for stack tests holds 10 years of events, from 2017 through 2026.
- Its 12 stack tests rank 13th of the 43 county cells in Pennsylvania for 2026.
- Its 12 stack tests are 1.9% of the 636 the state’s file holds for 2026.
Every line is computed by formula from the state’s stored file; nothing is estimated.
Air-emissions stack tests recorded in Mercer County, Pennsylvania, 2026
| Date | Facility | Kind | Agency |
|---|---|---|---|
| 2026-07-28 | HERMITAGE MUNI AUTH/HERMITAGE WPCP | Pass | State |
| 2026-07-21 | NATL FUEL GAS SUPPLY CORP/MERCER COMP STA | Pass | State |
| 2026-05-28 | RSI METAL LITHO/GREENVILLE | Pass | State |
| 2026-05-05 | CCL CONTAINER/ADVANCED MONOBLOC AEROSOL DIV — high-priority violation on file | Pass | State |
| 2026-05-04 | WABTEC US RAIL GROVE CITY ENGINE/MERCER | Pass | State |
| 2026-04-30 | PENNEX ALUM CO/GREENVILLE PLT | Pass | State |
| 2026-04-29 | HILCORP ENERGY CO/LACKAWANNOCK LARMON CTL FAC | Pass | State |
| 2026-04-21 | HILCORP ENERGY CO/JEFFERSON MONTGOMERY STA | Pass | State |
| 2026-04-17 | HILCORP ENERGY CO/LACKAWANNOCK LARMON CTL FAC | Pass | State |
| 2026-04-09 | TENNESSEE GAS PIPELINE CO LLC/MERCER STA 219 | Pass | State |
| 2026-03-27 | PIN OAK MIDSTREAM LLC/HURTT COMP STA | Pass | State |
| 2026-01-20 | NATL FUEL GAS SUPPLY CORP/MERCER COMP STA | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.
What this page shows
This page covers Clean Air Act facilities in the EPA air register, stack tests in Mercer county, PA, 2026. Stack tests recorded in 2026: 11.