EPA Air · stack tests by county and year
Air-emissions stack tests in Spencer County, Indiana, 2025
- 10Stack 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 Spencer County, Indiana 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 Spencer County facility page.
Air-emissions stack tests in Spencer County, other years
Air-emissions stack tests recorded in Spencer County, Indiana, 2025
| Date | Facility | Kind | Agency |
|---|---|---|---|
| 2025-12-22 | INDIANA MICHIGAN POWER COMPANY DBA AEP ROCKPORT PLANT | Pass | State |
| 2025-12-22 | INDIANA MICHIGAN POWER COMPANY DBA AEP ROCKPORT PLANT | Pass | State |
| 2025-09-24 | INDIANA MICHIGAN POWER COMPANY DBA AEP ROCKPORT PLANT | Pass | State |
| 2025-09-24 | INDIANA MICHIGAN POWER COMPANY DBA AEP ROCKPORT PLANT | Pass | State |
| 2025-09-24 | INDIANA MICHIGAN POWER COMPANY DBA AEP ROCKPORT PLANT | Pass | State |
| 2025-09-23 | INDIANA MICHIGAN POWER COMPANY DBA AEP ROCKPORT PLANT | Pass | State |
| 2025-09-23 | INDIANA MICHIGAN POWER COMPANY DBA AEP ROCKPORT PLANT | Pass | State |
| 2025-09-23 | INDIANA MICHIGAN POWER COMPANY DBA AEP ROCKPORT PLANT | Pass | State |
| 2025-06-05 | CLEVELAND-CLIFFS STEEL CORPORATION, ROCKPORT WORKS | Pass | State |
| 2025-06-03 | CLEVELAND-CLIFFS STEEL CORPORATION, ROCKPORT WORKS | 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 Spencer county, IN, in 2025. Stack tests recorded in 2025: 10.