EPA Air · stack tests by county and year

Air-emissions stack tests in Yellowstone County, Montana, 2020

74Stack 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 Yellowstone County, Montana during 2020. 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 Yellowstone County facility page.

Yellowstone County, Montana, 2020

Air-emissions stack tests in Yellowstone County, other years

Air-emissions stack tests recorded in Yellowstone County, Montana, 2020

Date	Facility	Kind	Agency
2020-12-18	PAR MONTANA BILLINGS REFINERY	Pass	State
2020-11-04	CHS INC REFINERY LAUREL	Pass	State
2020-11-04	CHS INC REFINERY LAUREL	Pass	State
2020-11-04	CHS INC REFINERY LAUREL	Pass	State
2020-11-04	CHS INC REFINERY LAUREL	Pass	State
2020-11-04	CHS INC REFINERY LAUREL	Pass	State
2020-11-04	CHS INC REFINERY LAUREL	Pass	State
2020-11-04	CHS INC REFINERY LAUREL	Pass	State
2020-10-13	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-09-30	YELLOWSTONE POWER PLANT — high-priority violation on file	Fail	State
2020-09-30	YELLOWSTONE POWER PLANT — high-priority violation on file	Fail	State
2020-09-30	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-09-30	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-09-30	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-09-30	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-09-29	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-08-28	CHS INC REFINERY LAUREL	Pass	State
2020-08-28	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-08-28	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-08-28	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-08-28	YELLOWSTONE POWER PLANT — high-priority violation on file	Fail	State
2020-08-28	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-08-28	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-08-27	CHS INC REFINERY LAUREL	Pass	State
2020-08-27	CHS INC REFINERY LAUREL	Pass	State
2020-08-27	CHS INC REFINERY LAUREL	Pass	State
2020-08-27	CHS INC REFINERY LAUREL	Pass	State
2020-08-27	CHS INC REFINERY LAUREL	Pass	State
2020-08-18	BILLINGS REFINERY	Pass	State
2020-08-04	CHS INC REFINERY LAUREL	Pass	State
2020-08-04	CHS INC REFINERY LAUREL	Pass	State
2020-08-04	CHS INC REFINERY LAUREL	Pass	State
2020-08-04	CHS INC REFINERY LAUREL	Pass	State
2020-08-04	CHS INC REFINERY LAUREL	Pass	State
2020-07-20	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-07-15	CHS INC REFINERY LAUREL	Pass	State
2020-07-15	CHS INC REFINERY LAUREL	Pass	State
2020-07-07	CHS INC REFINERY LAUREL	Pass	State
2020-07-07	CHS INC REFINERY LAUREL	Pass	State
2020-06-26	PAR MONTANA BILLINGS REFINERY	Pass	State
2020-06-25	PAR MONTANA BILLINGS REFINERY	Pass	State
2020-06-25	PAR MONTANA BILLINGS REFINERY	Pass	State
2020-06-17	PAR MONTANA BULK TERMINAL	Pass	State
2020-06-05	CHS INC REFINERY LAUREL	Pass	State
2020-06-05	CHS INC REFINERY LAUREL	Pass	State
2020-06-05	CHS INC REFINERY LAUREL	Pass	State
2020-06-05	CHS INC REFINERY LAUREL	Pass	State
2020-06-05	CHS INC REFINERY LAUREL	Pass	State
2020-06-05	CHS INC REFINERY LAUREL	Pass	State
2020-06-05	CHS INC REFINERY LAUREL	Pass	State
2020-06-05	CHS INC REFINERY LAUREL	Pass	State
2020-04-29	CHS INC REFINERY LAUREL	Pass	State
2020-04-29	CHS INC REFINERY LAUREL	Pass	State
2020-04-29	CHS INC REFINERY LAUREL	Pass	State
2020-04-29	CHS INC REFINERY LAUREL	Pass	State
2020-04-29	CHS INC REFINERY LAUREL	Pass	State
2020-04-29	CHS INC REFINERY LAUREL	Pass	State
2020-04-29	CHS INC REFINERY LAUREL	Pass	State
2020-04-21	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-04-21	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-04-21	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-04-03	CHS INC REFINERY LAUREL	Pass	State
2020-01-29	PAR MONTANA BILLINGS REFINERY	Pass	State
2020-01-27	PAR MONTANA BILLINGS REFINERY	Pass	State
2020-01-20	WESTERN SUGAR COOPERATIVE — high-priority violation on file	Pass	State
2020-01-20	WESTERN SUGAR COOPERATIVE — high-priority violation on file	Pass	State
2020-01-14	MONTANA SULPHUR & CHEMICAL	Pass	State
2020-01-12	BILLINGS REFINERY	Pass	State
2020-01-10	YELLOWSTONE POWER PLANT — high-priority violation on file	Pass	State
2020-01-08	BILLINGS REFINERY	Pass	State
2020-01-08	BILLINGS REFINERY	Pass	State
2020-01-08	BILLINGS REFINERY	Pass	State
2020-01-08	BILLINGS REFINERY	Pass	State
2020-01-08	BILLINGS REFINERY	Pass	State

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