EPA Air · by county
Air-emissions sources in Boulder County, Colorado
- 321Facilities
Every stationary source in Boulder County, Colorado that holds a Clean Air Act permit or is otherwise tracked by an air agency — planned, under construction, operating, seasonal or temporarily closed. Sources EPA records as permanently closed are not listed.
Every source’s record in Boulder County
Each of the 289 operating major, synthetic minor and minor sources in Boulder County, Colorado has a record page: every source in Boulder County, A to Z.
By emissions classification in Boulder County
A source’s classification is the size band its potential emissions put it in: a major source is large enough to need a Title V operating permit, a synthetic minor has accepted limits to stay below that line, and a minor source sits below it outright.
Inspections in Boulder County, by year
A compliance evaluation is the on-site or file review a state, local or federal air agency records against a permitted source.
- 2026 inspections 7
- 2025 inspections 30
- 2024 inspections 33
- 2023 inspections 40
- 2022 inspections 43
- 2021 inspections 57
- 2020 inspections 46
- 2019 inspections 49
- 2018 inspections 37
- 2017 inspections 41
Violations in Boulder County, by year
A high-priority violation is the most serious class of Clean Air Act non-compliance an agency records against a source; a federally reportable violation is the next step down in severity.
Stack tests in Boulder County, by year
A stack test measures what a source actually emits, at the stack, against the limit in its permit.
- 2026 stack tests 7
- 2025 stack tests 8
- 2024 stack tests 10
- 2023 stack tests 5
- 2022 stack tests 5
- 2021 stack tests 10
- 2020 stack tests 6
- 2019 stack tests 6
- 2018 stack tests 9
- 2017 stack tests 4
Inspections in Boulder County, year by year · Violations in Boulder County, year by year · Stack tests in Boulder County, year by year
Other counties in Colorado
Every county in the state with at least three sources on file.
- Adams County 869
- Alamosa County 23
- Arapahoe County 496
- Archuleta County 15
- Baca County 24
- Bent County 17
- Broomfield County 83
- Chaffee County 36
- Cheyenne County 132
- Clear Creek County 17
- Conejos County 8
- Costilla County 8
- Crowley County 5
- Custer County 14
- Delta County 51
- Denver County 595
- Dolores County 11
- Douglas County 155
- Eagle County 36
Facilities
County as filed on the facility record. Figures from EPA’s ICIS-AIR download.
What this page shows
This page covers Clean Air Act facilities in the EPA air register for Boulder county, CO. It lists 321 facilities in the county, of which 7 are major sources.