EPA Air · stack tests by county and year

Air-emissions stack tests in Clay County, Illinois, 2026

• 5Stack 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 Clay County, Illinois 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 Clay County facility page.

Air-emissions stack tests in Clay County, other years

• 2020 3

Air-emissions stack tests recorded in Clay County, Illinois, 2026

Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.