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.
What this page shows
This page covers Clean Air Act facilities in the EPA air register with stack tests in Howard county, MD, in 2025. Stack tests recorded in 2025: 4.