EPA Air · stack tests by county and year
Air-emissions stack tests in Howard County, Maryland, 2025
- 4Stack 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 Howard County, Maryland during 2025. 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 Howard County facility page.
Howard County, Maryland, 2025
Air-emissions stack tests in Howard County, other years
Air-emissions stack tests recorded in Howard County, Maryland, 2025
| Date | Facility | Kind | Agency |
|---|---|---|---|
| 2025-11-05 | TRANSCONTINENTAL GAS PIPELINE | Pass | State |
| 2025-08-12 | ALPHA RIDGE LANDFILL | Pass | State |
| 2025-08-05 | TRANSCONTINENTAL GAS PIPELINE | Pass | State |
| 2025-01-30 | TRANSCONTINENTAL GAS PIPELINE | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.