Velarion Records

The 340B register and hospital finances — joined, watched daily, delivered.

EPA Air · stack tests by county and year

Air-emissions stack tests in Mason County, Michigan, 2025

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 Mason County, Michigan 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 Mason County facility page.

Mason County, Michigan, 2025

Air-emissions stack tests in Mason County, other years

Air-emissions stack tests recorded in Mason County, Michigan, 2025

DateFacilityKindAgency
2025-06-13DTE MICHIGAN POWER, LLCPassState
2025-05-22OCCIDENTAL CHEMICAL CORPORATIONPassState
2025-05-22OCCIDENTAL CHEMICAL CORPORATIONPassState
2025-05-21OCCIDENTAL CHEMICAL CORPORATIONPassState
2025-05-01OCCIDENTAL CHEMICAL CORPORATIONPassState
2025-05-01OCCIDENTAL CHEMICAL CORPORATIONPassState

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