EPA Air · stack tests by county and year
Air-emissions stack tests in Hardin County, Iowa, 2026
- 15Stack 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 Hardin County, Iowa 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 Hardin County facility page.
Air-emissions stack tests in Hardin County, other years
Air-emissions stack tests recorded in Hardin County, Iowa, 2026
| Date | Facility | Kind | Agency |
|---|---|---|---|
| 2026-06-16 | MARTIN MARIETTA INC-ALDEN | Pass | State |
| 2026-05-20 | POET BIOREFINING IOWA FALLS, LLC — high-priority violation on file | Fail | State |
| 2026-05-19 | POET BIOREFINING IOWA FALLS, LLC — high-priority violation on file | Pass | State |
| 2026-05-08 | POET BIOREFINING IOWA FALLS, LLC — high-priority violation on file | Pass | State |
| 2026-05-07 | POET BIOREFINING IOWA FALLS, LLC — high-priority violation on file | Pass | State |
| 2026-05-06 | POET BIOREFINING IOWA FALLS, LLC — high-priority violation on file | Pass | State |
| 2026-05-06 | POET BIOREFINING IOWA FALLS, LLC — high-priority violation on file | Pass | State |
| 2026-05-06 | POET BIOREFINING IOWA FALLS, LLC — high-priority violation on file | Pass | State |
| 2026-05-05 | NATURALLY RECYCLED PROTEINS OF IOWA LLC | Pass | State |
| 2026-03-26 | PLCP, L.P. | Pass | State |
| 2026-03-26 | PLCP, L.P. | Pass | State |
| 2026-03-25 | PLCP, L.P. | Pass | State |
| 2026-03-25 | PLCP, L.P. | Pass | State |
| 2026-01-06 | CARGILL INC-IOWA FALLS | Pass | State |
| 2026-01-05 | CARGILL INC-IOWA FALLS | 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 Hardin county, IA, in 2026. It lists 15 stack tests recorded in 2026.