EPA Air · by county
Air-emissions sources in Middlesex County, Massachusetts
- 932Facilities
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Every stationary source in Middlesex County, Massachusetts 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 Middlesex County
Each of the 789 operating major, synthetic minor and minor sources in Middlesex County, Massachusetts has a record page: every source in Middlesex County, A to Z.
By emissions classification in Middlesex 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 Middlesex 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 124
- 2025 inspections 190
- 2024 inspections 185
- 2023 inspections 106
- 2022 inspections 63
- 2021 inspections 100
- 2020 inspections 103
- 2019 inspections 132
- 2018 inspections 127
- 2017 inspections 169
Violations in Middlesex 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.
- 2026 violations 6
- 2025 violations 18
- 2024 violations 10
- 2023 violations 17
- 2022 violations 9
- 2021 violations 7
- 2019 violations 7
- 2018 violations 10
- 2017 violations 10
Stack tests in Middlesex County, by year
A stack test measures what a source actually emits, at the stack, against the limit in its permit.
- 2026 stack tests 11
- 2025 stack tests 13
- 2024 stack tests 6
- 2023 stack tests 3
- 2022 stack tests 3
- 2021 stack tests 4
- 2019 stack tests 11
- 2017 stack tests 9
Inspections in Middlesex County, year by year · Violations in Middlesex County, year by year · Stack tests in Middlesex County, year by year
Other counties in Massachusetts
Every county in the state with at least three sources on file.
- Barnstable County 95
- Berkshire County 104
- Bristol County 484
- Dukes County 7
- Essex County 376
- Franklin County 66
- Hampden County 432
- Hampshire County 93
- Nantucket County 9
- Norfolk County 365
- Plymouth County 256
- Suffolk County 412
- Undetermined County 7
- Worcester County 696
Facilities
| Facility↑↓ | Classification↑↓ | HPV |
|---|---|---|
| 100 MEMORIAL DRIVE ASSOCIATES | Minor source | No |
| 1366 TECHNOLOGIES | Minor source | No |
| 18 PHOENIX PARK LLC | Minor source | No |
| 200 TECHNOLOGY SQUARE | Minor source | No |
| 21ST CENTURY BIOCHEMICALS | Minor source | No |
| 275 WYMAN LLC HOBBS BROOK MANAGEMENT LLC | Minor source | No |
| 290 BINNEY STREET AZ | No | |
| 3M CHELMSFORD | Minor source | No |
| 404 WYMAN LLC HOBBS BROOK MANAGEMENT | Minor source | No |
| 495 NETWORK CENTER | Minor source | No |
| 555 WATERTOWN LLC | Minor source | No |
| 610 LINCOLN STREET LLC | Minor source | No |
| 808 MEMORIAL DRIVE | No | |
| 81 WYMAN LLC OFFICE BUILDING | No | |
| A123 SYSTEMS | No | |
| AA WILL SAND & GRAVEL | Minor source | No |
| ABCAM INC | Minor source | Yes |
| ACCUTEST LABORATORIES OF NEW ENG | Minor source | No |
| ACE LON CORPORATION | Minor source | No |
| ACE-LON CORP | No | |
| ACT ELECTRONICS | Minor source | No |
| ACTON METAL PROCESSING CORP | Minor source | Yes |
| ACTON OPTICS & COATING | Minor source | No |
| ACTON REFINISHING COMPANY | Minor source | No |
| ACUSPHERE INC | Minor source | No |
| ACUSPHERE INC | Minor source | No |
| ADDISON WESLEY COMPANY | Minor source | No |
| ADESA AUCTION OF BOSTON | Synthetic minor source | No |
| ADVANCED MEMBRANE SYSTEMS INC | Minor source | No |
| ADVANCED SURFACE TECHNOLOGY | Minor source | Yes |
| AGENUS | Minor source | No |
| AGGREGATE INDUSTRIES INC | Minor source | No |
| AGGREGATE INDUSTRIES NORTHEAST | Synthetic minor source | No |
| AGGREGATE INDUSTRIES NORTHEAST (HOLCIM) | Synthetic minor source | No |
| AGILENT TECHNOLOGIES | Minor source | No |
| AGILENT TECHNOLOGIES INC | Minor source | No |
| AI USED AUTO PARTS | Minor source | No |
| AIR LIQUID ADVANCED TECHNOLOGIES | Synthetic minor source | Yes |
| ALEXANDRIA REAL ESTATE | Synthetic minor source | No |
| ALEXANDRIA REAL ESTATE EQUITIES INC | Minor source | No |
| ALKERMES INC | Minor source | No |
| ALLCOAT TECHNOLOGY INC | Synthetic minor source | No |
| ALLIED INDUSTRIES | Minor source | No |
| ALLIED WASTE SYSTEMS | Minor source | No |
| ALNYLAM PHARMACEUTALS | Minor source | No |
| ALNYLAM PHARMACEUTICAL | No | |
| ALNYLAM PHARMACEUTICALS | Minor source | No |
| ALPHA AUTO BODY | Minor source | No |
| ALPHA OMEGA AUTO BODY | No | |
| AMAZON.COM LLC - DK01 | No | |
| AMBRI | Minor source | No |
| AMCOR FLEXIBLES HEALTHCARE | Minor source | No |
| AMERICAN DURAFILM CO INC | Minor source | No |
| AMERICAN FURNITURE RENTALS | Minor source | No |
| AMERICAN SCIENCE & TECHNOLOGY | Minor source | No |
| AMERICAN TOWER | No | |
| AMERICRAFT CARTON INC | Minor source | No |
| AMES ON DEMAND | Minor source | No |
| AMETEK AEROSPACE INCORPORATED | Minor source | No |
| AMGEN | Synthetic minor source | No |
| AMRIZE NORTHEAST INC | Synthetic minor source | No |
| AMSPEC | No | |
| ANALOG DEVICES | Minor source | No |
| ANALOG DEVICES INC | Synthetic minor source | No |
| ANALOGIC CORPORATION | Minor source | No |
| ANDE CORPORATION | No | |
| ANDOVER NEWTON THEOLOGICAL SCHOOL | Minor source | No |
| ANGELICA TEXTILE SERVICES | Minor source | No |
| ANIKA THERAPEUTICS INC | Synthetic minor source | No |
| ANJEN FINISHING | Minor source | No |
| ANTONS CLEANERS | Minor source | No |
| AOA XINETICS/ADAPTIVE OPTICS | No | |
| AOTCO METAL FINISHING | Synthetic minor source | No |
| ARC TECH SQUARE LLC | Minor source | No |
| ARDENT MILLS LLC | Minor source | No |
| ARE MA REGION NO 107 OWNER LLC | No | |
| ARIAD PHARMACEUTICALS INC | Minor source | No |
| ARLIN MFG CO INC | Synthetic minor source | No |
| ARLINGTON HOUSING AUTHORITY | Minor source | No |
| ARLINGTON REDEVELOPMENT BOARD | Minor source | No |
| ARQULE INCORPORATED | Emissions classification unknown | No |
| ARTISAN INDUSTRIES INCORPORATED | Minor source | No |
| ASHBURNHAM FINISHING | Minor source | No |
| ASHLAND HIGH SCHOOL | Minor source | No |
| ASHLAND TECHNOLOGY CENTER | Synthetic minor source | No |
| ASTRAZENECA PHARMACEUTICALS LP | Synthetic minor source | No |
| AT&T | Synthetic minor source | No |
| AT&T CAMBRIDGE | Synthetic minor source | No |
| AT&T FRAMINGHAM | Synthetic minor source | No |
| AT&T LITTLETON | Minor source | No |
| AT&T MOBILITY | Minor source | No |
| ATHENA DIAGNOSTICS | Minor source | No |
| ATHENA HEALTH INC | Synthetic minor source | No |
| ATLANTIC BATTERY | Minor source | No |
| AVCARB MATERIAL SOLUTIONS | Synthetic minor source | No |
| AVERICA DISCOVERY SERVICES INC | Minor source | No |
| AVERY DENNISON CORP | Minor source | No |
| AXSUN TECHNOLOGIES | Minor source | No |
| BAE SYSTEMS | Synthetic minor source | No |
| BAKER COMMODITIES | Synthetic minor source | No |
County as filed on the facility record. Figures from EPA’s ICIS-AIR download.