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 |
|---|---|---|---|---|
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-07 | LINN OPERATING INC — high-priority violation on file | TAFT, Kern, CA | Pass | Local |
| 2025-10-06 | DANIEL COMPANY LLC | ADELANTO, San Bernardino, CA | Pass | Local |
| 2025-10-06 | CAMPOS BROTHERS | CARUTHERS, Fresno, CA | Pass | Local |
| 2025-10-06 | CAMPOS BROTHERS | CARUTHERS, Fresno, CA | Pass | Local |
| 2025-10-02 | SACRAMENTO AREA SEWER DISTRICT | ELK GROVE, Sacramento, CA | Pending | Local |
| 2025-10-02 | SILGAN CONTAINERS | SACRAMENTO, Sacramento, CA | Pass | Local |
| 2025-10-02 | PHILLIPS 66 COMPANY/LA REFINERY | CARSON, Los Angeles, CA | Pass | Local |
| 2025-10-02 | KERN OIL & REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-10-02 | KERN OIL & REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-10-02 | KERN OIL & REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-10-02 | KERN OIL & REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-10-02 | KERN OIL & REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-10-02 | KERN OIL & REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-10-02 | KERN OIL & REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-10-02 | KERN OIL & REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-10-02 | KERN OIL & REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-10-02 | KERN OIL & REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-10-02 | KERN OIL & REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-10-02 | KERN OIL & REFINING — high-priority violation on file | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-10-02 | EQUILON ENTERPRISES LLC | STOCKTON, San Joaquin, CA | Pass | Local |
| 2025-10-02 | EQUILON ENTERPRISES LLC | STOCKTON, San Joaquin, CA | Pass | Local |
| 2025-10-02 | EQUILON ENTERPRISES LLC | STOCKTON, San Joaquin, CA | Pass | Local |
| 2025-10-02 | EQUILON ENTERPRISES LLC | STOCKTON, San Joaquin, CA | Pass | Local |
| 2025-10-02 | EQUILON ENTERPRISES LLC | STOCKTON, San Joaquin, CA | Pass | Local |
| 2025-10-02 | EQUILON ENTERPRISES LLC | STOCKTON, San Joaquin, CA | Pass | Local |
| 2025-10-02 | EQUILON ENTERPRISES LLC | STOCKTON, San Joaquin, CA | Pass | Local |
| 2025-10-02 | EQUILON ENTERPRISES LLC | STOCKTON, San Joaquin, CA | Pass | Local |
| 2025-10-01 | LA CITY, DWP HARBOR GENERATING STATION | WILMINGTON, Los Angeles, CA | Pass | Local |
| 2025-09-30 | MONTEREY ONE WATER (PREVIOUSLY MONTEREY REGIONAL WTR POLLUTION CTRL) | MARINA, Monterey, CA | Pass | Local |
| 2025-09-29 | MITSUBISHI CEMENT CO — high-priority violation on file | LUCERNE VALLEY, San Bernardino, CA | Pass | Local |
| 2025-09-29 | MITSUBISHI CEMENT CO — high-priority violation on file | LUCERNE VALLEY, San Bernardino, CA | Pass | Local |
| 2025-09-29 | TESORO REFINING MARKETING COMPANY LLC | SOUTH GATE, Los Angeles, CA | Pass | Local |
| 2025-09-29 | TESORO REFINING MARKETING COMPANY LLC | SOUTH GATE, Los Angeles, CA | Pass | Local |
| 2025-09-26 | LA CITY, DWP HARBOR GENERATING STATION | WILMINGTON, Los Angeles, CA | Pass | Local |
| 2025-09-25 | PHILLIPS 66 CO/LA REFINERY WILMINGTON — high-priority violation on file | WILMINGTON, Los Angeles, CA | Pass | Local |
| 2025-09-25 | OC WASTE & RECYCLING, FRB | IRVINE, Orange, CA | Fail | Local |
| 2025-09-25 | CALPEAK POWER BORDER LLC | SAN DIEGO, San Diego, CA | Pending | Local |
| 2025-09-25 | E&B NATIONAL RESOURCES MANAGEMENT | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-09-25 | E&B NATIONAL RESOURCES MANAGEMENT | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-09-25 | E&B NATIONAL RESOURCES MANAGEMENT | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-09-25 | E&B NATIONAL RESOURCES MANAGEMENT | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-09-25 | E&B NATIONAL RESOURCES MANAGEMENT | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-09-25 | E&B NATIONAL RESOURCES MANAGEMENT | BAKERSFIELD, Kern, CA | Pass | Local |
| 2025-09-25 | HILMAR CHEESE COMPANY — high-priority violation on file | HILMAR, Merced, CA | Pass | Local |
| 2025-09-25 | HILMAR CHEESE COMPANY — high-priority violation on file | HILMAR, Merced, CA | Pass | Local |
| 2025-09-25 | HILMAR CHEESE COMPANY — high-priority violation on file | HILMAR, Merced, CA | Pass | Local |
| 2025-09-25 | HILMAR CHEESE COMPANY — high-priority violation on file | HILMAR, Merced, CA | Pass | Local |
| 2025-09-24 | LA CITY, DWP HARBOR GENERATING STATION | WILMINGTON, Los Angeles, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
| 2025-09-24 | MODESTO IRRIGATION DISTRICT | RIPON, San Joaquin, CA | Pass | Local |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.