Total TRI releases
Total TRI releases at Chester County have more than three-quarters since 2010 (through 2024).
County · TRI 2024
Chester County, Pennsylvania Pollution
10 top TRI facilities tracked here. PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) fell meaningfully year over year (-33%). PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) concentrations have fallen 48% since 2011.
FIPS 42029 · population 536,474
Anomaly engine
Notable Signals
Top facilities mapped
Where Chemicals Are Released In Chester County
Each red dot is one of the top TRI facilities. Size reflects 2024 total releases. County boundary outlined in blue.
Pollutant pathways
Chester County Pollutant Multi-Year Trends
PM2.5 annual mean (NAAQS 9 µg/m³ (annual))Health riskFine inhalable particles 2.5 micrometers or smaller. They travel deep into the lungs and into the bloodstream — linked to asthma, heart disease, stroke, and premature death.
PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) concentrations have fallen 48% since 2011.
PM2.5 24-hour 98th percentile (NAAQS 35 µg/m³ (24-hour))Health riskFine inhalable particles 2.5 micrometers or smaller. They travel deep into the lungs and into the bloodstream — linked to asthma, heart disease, stroke, and premature death.
PM2.5 24-hour 98th percentile (NAAQS 35 µg/m³ (24-hour)) concentrations have more than halved since 2011.
Ozone 8-hour 4th-highest daily max (NAAQS 0.070 ppm (8-hour))Health riskGround-level ozone (smog) forms when vehicle and industrial emissions react in sunlight. Inflames the airways, triggers asthma attacks, and worsens heart and lung disease.
Ozone 8-hour 4th-highest daily max (NAAQS 0.070 ppm (8-hour)) concentrations have fallen 13% since 2010.
Lifetime cancer risk all pollutants (100 in a million (EPA elevated threshold))Health riskEPA-modeled added cancer cases per million residents from a lifetime of breathing local air toxics. EPA flags 100-in-a-million as elevated.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Formaldehyde ambient mean (0.077 µg/m³ (1-in-a-million URE))Health riskAn air toxic emitted by refineries, wood products, and combustion. EPA classifies it as a known human carcinogen — long-term inhalation raises cancer risk.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Benzene ambient mean (0.13 µg/m³ (1-in-a-million URE))Health riskAn air toxic from gasoline, refineries, and tobacco smoke. A known human carcinogen — chronic exposure is linked to leukemia and other blood cancers.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
TRI air releases (5.1 fugitive + 5.2 stack)Health riskToxic chemicals reported by industrial facilities as released into the air — fugitive leaks plus smokestack emissions. Higher pounds means more inhaled exposure for nearby residents.
TRI air releases (5.1 fugitive + 5.2 stack) concentrations have more than halved since 2010.
TRI water releases (5.3)Health riskToxic chemicals reported by industrial facilities as discharged to surface waters (rivers, lakes, the ocean). Affects fishing, recreation, and downstream drinking-water intakes.
TRI water releases (5.3) volumes here are too small to anchor a multi-year trend; YoY movement is still shown above.
TRI land + off-site releasesHealth riskToxic chemicals released to land on-site or transferred off-site for disposal — landfills, deep-well injection, and similar. Risks groundwater contamination over time.
TRI land + off-site releases concentrations have fallen 21% since 2010.
Greenhouse gases (GHGRP large emitters, through 2023)Health riskGreenhouse gases reported by large industrial emitters under EPA's GHGRP, in metric tons of CO₂ equivalent. Drives climate warming and the heat-related health effects that follow.
Greenhouse gases (GHGRP large emitters, through 2023) concentrations have more than halved since 2010.
Top facilities · 2024
Where The Chemical Releases Are Concentrated
| Facility | City | Top chemical | Total releases | YoY |
|---|---|---|---|---|
| Cleveland-Cliffs Plate LLC Coatesville FacilityCleveland-Cliffs INC | Coatesville | Nickel And Nickel CompoundsHealth riskNickel compounds are IARC Group 1 carcinogens; inhalation exposure raises lung and nasal cancer risk. (IARC) | 113k lb | -3% |
| Johnson Matthey INCJohnson Matthey Holdings INC | Wayne | Nitrate compounds (water dissociable; reportable only when in aqueous solution)Health riskDrinking-water nitrate causes methemoglobinemia ('blue-baby syndrome') in infants; EPA MCL is 10 mg/L as N. (EPA) | 21k lb | +51% |
| Arkema West Chester PlantArkema Delaware INC | West Chester | TolueneHealth riskCentral-nervous-system depressant. Chronic high exposure causes hearing loss and developmental effects. (EPA, ATSDR) | 13k lb | -4% |
| Agc Chemicals Americas INCAgc America INC | Downingtown | CopperHealth riskInhaled copper fumes cause metal-fume fever; chronic ingestion above EPA's 1.3 mg/L action level damages the liver. (EPA) | 6k lb | +5% |
| Taylor Industries INC. | Parker Ford | StyreneHealth riskIARC Group 2A probable carcinogen; central-nervous-system effects from inhalation. (IARC, EPA) | 5k lb | -14% |
| Delaware Valley Custom Marble INC | West Grove | StyreneHealth riskIARC Group 2A probable carcinogen; central-nervous-system effects from inhalation. (IARC, EPA) | 5k lb | +48% |
| Metallurgical Products COKramer International LLC | West Chester | CopperHealth riskInhaled copper fumes cause metal-fume fever; chronic ingestion above EPA's 1.3 mg/L action level damages the liver. (EPA) | 5k lb | -27% |
| Whitford CorpPpg Industries INC | Elverson | N-Methyl-2-pyrrolidoneHealth riskReproductive and developmental toxicant; absorbed through skin. (EPA) | 4k lb | -93% |
| Action Manufacturing COAction Manufacturing Co | Atglen | Lead And Lead CompoundsHealth riskNeurotoxin. Even low childhood exposure impairs cognitive development; chronic adult exposure damages kidneys and the cardiovascular system. (EPA, ATSDR) | 1k lb | +3% |
| Dsm BiomedicalDsm Holding Co USA INC | Exton | N,N-DimethylformamideHealth riskHepatotoxin; absorbed through skin; IARC Group 2A probable carcinogen. (IARC) | 750 lb | 0% |
Superfund / NPL sites
Federal Cleanup Sites In Chester County
Sites on EPA's Superfund National Priorities List, plus deleted sites whose cleanup objectives EPA has finalized. Federal-facility sites (defense, DOE, etc.) are flagged separately. Each link routes to a per-site page.
| Site | City | Status | Federal facility | Primary contaminant |
|---|---|---|---|---|
| A.I.W. Frank/Mid-County Mustang | Exton | NPL FINAL | No | 1,1-DichloroethaneHealth riskSuspected carcinogen (EPA C/likely); CNS depressant. Common at solvent-contaminated sites as a degradation intermediate. (EPA, ATSDR) |
| Blosenski Landfill | West Caln Township | NPL FINAL | No | AcetoneHealth riskLow chronic toxicity; high acute exposure causes CNS depression and respiratory irritation. (EPA, NIOSH) |
| Foote Mineral Co. | East Whiteland Township | NPL FINAL | No | AntimonyHealth riskInhaled antimony trioxide is an IARC Group 2B possible carcinogen; respiratory and cardiovascular effects from long-term exposure. EPA MCL 6 µg/L. (IARC, EPA) |
| Kimberton | East Pikeland Township | NPL FINAL | No | Chloroethene (Vinyl Chloride)Health riskIARC Group 1 carcinogen — angiosarcoma of the liver. Final TCE/PCE biodegradation product; commonly found in groundwater plumes. EPA MCL 2 µg/L. (IARC, EPA) |
| Malvern Tce | Malvern | NPL FINAL | No | 1,4-DioxaneHealth riskIARC Group 2B possible carcinogen; persistent in groundwater, resists conventional treatment. EPA HRL 0.35 µg/L (10⁻⁶ cancer risk). (IARC, EPA) |
| Old Wilmington Road Gw Contamination | West Caln Township | NPL FINAL | No | 1,4-DioxaneHealth riskIARC Group 2B possible carcinogen; persistent in groundwater, resists conventional treatment. EPA HRL 0.35 µg/L (10⁻⁶ cancer risk). (IARC, EPA) |
| Paoli Rail Yard | Paoli | NPL FINAL | No | Aroclor 1260Health riskPCBs. IARC Group 1 carcinogen; immune, reproductive, and neurological effects; bioaccumulate in fish and breast milk. Banned in 1979; persist as legacy contamination. (IARC, EPA) |
| Walsh Landfill | Honeybrook Township | NPL FINAL | No | ArsenicHealth riskIARC Group 1 carcinogen via inhalation and ingestion. EPA MCL 10 µg/L; chronic exposure causes skin, lung, bladder cancer and cardiovascular disease. (IARC, EPA, ATSDR) |
| William Dick Lagoons | West Caln Township | NPL FINAL | No | 1,1,1-TrichloroethaneHealth riskMethyl chloroform. CNS depressant; ozone-depleting substance phased out under Montreal Protocol. EPA MCL 200 µg/L. (EPA, ATSDR) |
| Recticon/Allied Steel Corp. | E Coventry Twp | DELETED | No | 1,1-DichloroetheneHealth riskVinylidene chloride; IARC Group 3 (inadequate evidence in humans) but liver toxic in animal studies; common TCE/PCE biodegradation product. (IARC, EPA) |
Showing the top 10 sites by status priority. 1 additional NPL-relevant sites in Chester County have entity pages — browse them via the host-county or host-city page rollups.
Equity context · ACS 2018-2022 · USEPA-clone EJ disparity
Who Lives In Chester County
All block groups in Chester County County, PA: 536,474 residents. County disparity score for pm2.5 (fine particulate) sits well below the reference (40). Why we surface this →
6.0%
Low-income
22.6%
People of color
6.0%
Under age 5
17.0%
Over age 64
- PM2.5 (fine particulate)Health riskFine inhalable particles 2.5 micrometers or smaller. They travel deep into the lungs and into the bloodstream — linked to asthma, heart disease, stroke, and premature death.57near the national median
- OzoneHealth riskGround-level ozone (smog) inflames the airways. Even short exposures trigger asthma attacks and worsen chronic lung and heart disease.47near the national median
- Nitrogen dioxide (NO₂)Health riskA tailpipe and combustion gas. Concentrates near busy roads and industrial sites; raises risk of airway inflammation, asthma, and lower respiratory infections in children.37below the national median
- Diesel particulateHealth riskSoot from diesel engines (trucks, trains, ports, construction). EPA classifies it as a likely human carcinogen and a major driver of childhood asthma near freight corridors.55near the national median
- Toxic releases (RSEI)Health riskEPA's Risk-Screening Environmental Indicators score — weights TRI chemical releases by toxicity, where they go, and how many people are nearby. Higher means greater modeled cancer and chronic-health risk.81in the highest 20% nationally
- Traffic proximityHealth riskPopulation-weighted distance to high-volume roads. Living close to heavy traffic raises exposure to PM2.5, NO₂, and diesel exhaust — and the cardiovascular and asthma risks that follow.48near the national median
- Lead-paint risk (pre-1960 housing)Health riskShare of housing built before 1960, when lead-based paint was common. Dust from deteriorating paint is the leading cause of childhood lead poisoning, which permanently impairs cognitive development.59near the national median
- Superfund site proximityHealth riskPopulation-weighted distance to NPL Superfund sites — the most contaminated waste sites in the country. Nearby groundwater, soil, and air can carry industrial solvents, metals, and other long-lived contaminants.85in the highest 20% nationally
- RMP-facility proximityHealth riskDistance to facilities holding chemicals at quantities large enough to require an EPA Risk Management Plan (refineries, fertilizer plants, etc.). These pose acute exposure risk during accidental releases.56near the national median
- Hazardous-waste site proximityHealth riskDistance to RCRA hazardous-waste handlers (treatment, storage, disposal facilities). Indicates potential exposure to industrial chemicals in air, soil, and groundwater.54near the national median
- Underground storage tanksHealth riskDensity of underground tanks (gasoline, heating oil, industrial fluids). Leaking tanks are a leading source of benzene and other volatile organic compounds in groundwater drinking-water supplies.66above the national median
- NPDES wastewater proximityHealth riskDistance to permitted industrial wastewater dischargers. Closer proximity raises exposure to pollutants released into surface waters used for fishing, recreation, and downstream drinking-water intakes.68above the national median
- Drinking-water non-complianceHealth riskEPA score for public water systems with health-based Safe Drinking Water Act violations. Higher means more residents on systems that recently exceeded safe limits for contaminants like lead, arsenic, or nitrate.78above the national median
| Indicator | Disparity score | Reading |
|---|---|---|
| PM2.5 (fine particulate) | 40 | well below the reference |
| Ozone | 43 | well below the reference |
| Nitrogen dioxide (NO₂) | 28 | well below the reference |
| Diesel particulate | 38 | well below the reference |
| Toxic releases (RSEI) | 54 | below the reference |
| Traffic proximity | 30 | well below the reference |
| Lead-paint risk (pre-1960 housing) | 36 | well below the reference |
| Superfund site proximity | 49 | well below the reference |
| RMP-facility proximity | 33 | well below the reference |
| Hazardous-waste site proximity | 33 | well below the reference |
| Underground storage tanks | 37 | well below the reference |
| NPDES wastewater proximity | 38 | well below the reference |
| Drinking-water non-compliance | 6 | well below the reference |
Source: Census ACS 2018-2022 (5-year) + USEPA-clone EJ blockgroup stats (raw indicators + EJ disparity mirror).
Browse
All 22 Chester County Cities With TRI Data
Pollution trends and TRI 2024 pages for every tracked city in this county. Alphabetical.
- Atglen pollution· 0 facilities
- Avondale pollution· 0 facilities
- Coatesville pollution· 0 facilities
- Cochranville pollution· 0 facilities
- Downingtown pollution· 1 facility
- Elverson pollution· 1 facility
- Exton pollution· 0 facilities
- Glenmoore pollution· 0 facilities
- Honey Brook pollution· 0 facilities
- Kennett Square pollution· 0 facilities
- Kimberton pollution· 0 facilities
- Nottingham pollution· 0 facilities
- Oxford pollution· 0 facilities
- Parkesburg pollution· 0 facilities
- Phoenixville pollution· 0 facilities
- South Coatesville pollution· 1 facility
- Spring City pollution· 0 facilities
- Thorndale pollution· 1 facility
- Toughkenamon pollution· 0 facilities
- Unionville pollution· 0 facilities
- West Chester pollution· 1 facility
- West Grove pollution· 0 facilities
Sources.
- EPA Toxics Release Inventory · retrieved 2026-05-07.
All sources are federal public-domain datasets under 17 USC §105. We aggregate but do not relabel; the underlying observations remain attributable to EPA.