EPA Air · stack tests by state and year
Air-emissions stack tests in California, 2025
- 5,390Stack tests
A stack test measures what a source actually emits, at the stack, against the limit in its permit. Every stack test below was recorded against a source in California during 2025; one facility can appear more than once, because this is a record of what happened rather than a list of places.
Counties in California, 2025
- Kern County 3,380
- Stanislaus County 579
- San Joaquin County 413
- Fresno County 211
- Merced County 170
- Tulare County 157
- Los Angeles County 139
- Madera County 91
- San Bernardino County 74
- Monterey County 49
- Riverside County 29
- Kings County 23
- Sacramento County 17
- Ventura County 17
- San Diego County 11
- Orange County 10
- Santa Cruz County 7
- Undetermined County 6
- Humboldt County 6
California, other years
Air-emissions stack tests recorded in California, 2025
| Date | Facility | Where | Kind | Agency |
|---|---|---|---|---|
| 2025-11-17 | LADW&P-HAYNES STEAM | LONG BEACH, Los Angeles, CA | Pass | Local |
| 2025-11-13 | AERA ENERGY LLC | SAN ARDO, Monterey, CA | Pass | Local |
| 2025-11-13 | ARROWHEAD REGIONAL MEDICAL CENTER — high-priority violation on file | COLTON, San Bernardino, CA | Pass | Local |
| 2025-11-13 | ARROWHEAD REGIONAL MEDICAL CENTER — high-priority violation on file | COLTON, San Bernardino, CA | Pass | Local |
| 2025-11-13 | ARROWHEAD REGIONAL MEDICAL CENTER — high-priority violation on file | COLTON, San Bernardino, CA | Pass | Local |
| 2025-11-12 | MCCLELLAN BUSINESS PARK — high-priority violation on file | MCCLELLAN, Sacramento, CA | Pending | Local |
| 2025-11-12 | PHILLIPS 66 COMPANY/LA REFINERY | CARSON, Los Angeles, CA | Pass | Local |
| 2025-11-12 | SENTINEL PEAK RESOURCES CA LLC — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-11 | SALINAS VALLEY SOLID WASTE AUTHORITY | GONZALES, Monterey, CA | Pass | Local |
| 2025-11-11 | PHILLIPS 66 CO/LA REFINERY WILMINGTON — high-priority violation on file | WILMINGTON, Los Angeles, CA | Pass | Local |
| 2025-11-11 | SENTINEL PEAK RESOURCES CA LLC — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-10 | TESORO REFINING AND MARKETING CO — high-priority violation on file | WILMINGTON, Los Angeles, CA | Pass | Local |
| 2025-11-10 | LA CO. SANITATION DIST | CARSON, Los Angeles, CA | Pass | Local |
| 2025-11-10 | PHILLIPS 66 PIPELINE LLC | LOS ANGELES, Los Angeles, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | CHEVRON USA INC- HEAVY OIL — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-07 | FOSTER FOOD PRODUCTS — high-priority violation on file | LIVINGSTON, Merced, CA | Pass | Local |
| 2025-11-07 | FOSTER FOOD PRODUCTS — high-priority violation on file | LIVINGSTON, Merced, CA | Pass | Local |
| 2025-11-07 | CALIFORNIA DAIRIES, INC. — high-priority violation on file | TURLOCK, Stanislaus, CA | Fail | Local |
| 2025-11-07 | CALIFORNIA DAIRIES, INC. — high-priority violation on file | TURLOCK, Stanislaus, CA | Fail | Local |
| 2025-11-07 | CALIFORNIA DAIRIES, INC. — high-priority violation on file | TURLOCK, Stanislaus, CA | Fail | Local |
| 2025-11-07 | CALIFORNIA DAIRIES, INC. — high-priority violation on file | TURLOCK, Stanislaus, CA | Fail | Local |
| 2025-11-07 | CALIFORNIA DAIRIES, INC. — high-priority violation on file | TURLOCK, Stanislaus, CA | Fail | Local |
| 2025-11-07 | CALIFORNIA DAIRIES, INC. — high-priority violation on file | TURLOCK, Stanislaus, CA | Fail | Local |
| 2025-11-07 | CALIFORNIA DAIRIES, INC. — high-priority violation on file | TURLOCK, Stanislaus, CA | Fail | Local |
| 2025-11-07 | CALIFORNIA DAIRIES, INC. — high-priority violation on file | TURLOCK, Stanislaus, CA | Fail | Local |
| 2025-11-06 | BLYTHE ENERGY LLC (FPL FLORIDA POWER) | BLYTHE, Riverside, CA | Pass | Local |
| 2025-11-06 | PACIFIC BELL TELEPHONE CO (DBA AT&T CA) | FRESNO, Fresno, CA | Pass | Local |
| 2025-11-06 | PACIFIC BELL TELEPHONE CO (DBA AT&T CA) | FRESNO, Fresno, CA | Pass | Local |
| 2025-11-06 | PACIFIC BELL TELEPHONE CO (DBA AT&T CA) | FRESNO, Fresno, CA | Pass | Local |
| 2025-11-06 | SIMI VALLEY LANDFILL & RECYCLING CENTER — high-priority violation on file | SIMI VALLEY, Ventura, CA | Pass | Local |
| 2025-11-05 | HILMAR CHEESE COMPANY — high-priority violation on file | HILMAR, Merced, CA | Pass | Local |
| 2025-11-05 | HILMAR CHEESE COMPANY — high-priority violation on file | HILMAR, Merced, CA | Pass | Local |
| 2025-11-05 | HILMAR CHEESE COMPANY — high-priority violation on file | HILMAR, Merced, CA | Pass | Local |
| 2025-11-04 | BLYTHE ENERGY LLC (FPL FLORIDA POWER) | BLYTHE, Riverside, CA | Pass | Local |
| 2025-11-04 | ALON BAKERSFIELD REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-04 | ALON BAKERSFIELD REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-04 | ALON BAKERSFIELD REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-04 | ALON BAKERSFIELD REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-04 | ALON BAKERSFIELD REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-04 | DELICATO VINEYARDS | MANTECA, San Joaquin, CA | Pass | Local |
| 2025-11-04 | DELICATO VINEYARDS | MANTECA, San Joaquin, CA | Pass | Local |
| 2025-11-04 | DELICATO VINEYARDS | MANTECA, San Joaquin, CA | Pass | Local |
| 2025-11-04 | DELICATO VINEYARDS | MANTECA, San Joaquin, CA | Pass | Local |
| 2025-11-04 | DELICATO VINEYARDS | MANTECA, San Joaquin, CA | Pass | Local |
| 2025-11-04 | DELICATO VINEYARDS | MANTECA, San Joaquin, CA | Pass | Local |
| 2025-11-03 | SAN JOAQUIN REFINING CO — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-03 | SAN JOAQUIN REFINING CO — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-11-03 | SAN JOAQUIN REFINING CO — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-10-31 | HP HOOD, LLC — high-priority violation on file | SACRAMENTO, Sacramento, CA | Pending | Local |
| 2025-10-30 | PHILLIPS 66 COMPANY | SACRAMENTO, Sacramento, CA | Pending | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
| 2025-10-29 | WELLHEAD POWER PANOCHE, LLC — high-priority violation on file | FIREBAUGH, Fresno, CA | Pass | Local |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.