TRI air releases
TRI air releases at Wisconsin have more than halved since 2010 (through 2024).
State · TRI 2024
Wisconsin Pollution
686 TRI facilities, 977 public water systems, and 46 Superfund / NPL sites across 63 counties. Statewide TRI releases fell meaningfully year over year (-21%). Toxic releases concentrations have fallen 45% since 2010.
FIPS 55 · population 5,893,718 · 72 counties total
Anomaly engine
Notable Signals At The State Level
Where the burden sits
County-Level TRI Choropleth
A color-shaded map of pollution data. Darker counties report more pounds of toxic chemicals released to the EPA's Toxics Release Inventory (TRI).
Shaded by total reported releases for 2024. Counties without a published page render as “no TRI data”. Red dots mark this state's top emitters.
Statewide pollutant pathways
Wisconsin 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 49% since 2010.
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 fallen 48% since 2010.
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.
NO₂ annual mean (NAAQS 53 ppb (annual))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.
NO₂ annual mean (NAAQS 53 ppb (annual)) concentrations have more than halved 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) concentrations are roughly unchanged from 2010.
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 42% 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 fallen 13% since 2010.
| County | Population | Facilities | Total releases | YoY | Top chemical |
|---|---|---|---|---|---|
| Marathon CountyFIPS 55073 | 137,820 | 30 | 3.3M lb | -20% | 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) |
| Waupaca CountyFIPS 55135 | 51,822 | 9 | 2.1M lb | -12% | Zinc compoundsHealth riskGenerally low acute toxicity. Chronic high-dose exposure disrupts copper absorption and immune function. (ATSDR) |
| Milwaukee CountyFIPS 55079 | 933,063 | 76 | 2.0M lb | -5% | Methyl isobutyl ketoneHealth riskEye, skin, and respiratory irritant; central-nervous-system depressant at high exposure. (NIOSH) |
| Portage CountyFIPS 55097 | 70,281 | 9 | 1.4M lb | +3% | 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) |
| Ozaukee CountyFIPS 55089 | 91,745 | 10 | 958k lb | +17% | Zinc compoundsHealth riskGenerally low acute toxicity. Chronic high-dose exposure disrupts copper absorption and immune function. (ATSDR) |
| Brown CountyFIPS 55009 | 268,393 | 45 | 932k lb | +14% | 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) |
| Outagamie CountyFIPS 55087 | 190,611 | 24 | 919k lb | -4% | MethanolHealth riskAcutely toxic if ingested or inhaled. Metabolizes to formaldehyde and formic acid, causing blindness and metabolic acidosis. (EPA) |
| Douglas CountyFIPS 55031 | 44,092 | 5 | 811k lb | +26% | Hydrochloric acid (acid aerosols including mists, vapors, gas, fog, and other airborne forms of any particle size)Health riskAerosolized HCl is a corrosive respiratory irritant; chronic exposure damages teeth and respiratory tissue. (NIOSH) |
| Winnebago CountyFIPS 55139 | 171,197 | 23 | 789k lb | -11% | Zinc (fume or dust)Health riskGenerally low acute toxicity. Chronic high-dose exposure disrupts copper absorption and immune function. (ATSDR) |
| Sheboygan CountyFIPS 55117 | 117,741 | 24 | 712k lb | +13% | Zinc compoundsHealth riskGenerally low acute toxicity. Chronic high-dose exposure disrupts copper absorption and immune function. (ATSDR) |
| Facility | City | Top chemical | Total releases | YoY |
|---|---|---|---|---|
| Mullins Cheese INCMullins Cheese INC | Mosinee | 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) | 1.6M lb | -32% |
| Mccain Foods USA INCMccain Foods USA INC | Wisconsin Rapids | 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) | 1.4M lb | +3% |
| Waupaca Foundry Plant 1Monomoy Capital Partners | Waupaca | Zinc compoundsHealth riskGenerally low acute toxicity. Chronic high-dose exposure disrupts copper absorption and immune function. (ATSDR) | 1.2M lb | +16% |
| Ppg Industries Inc-Oak CreekPpg Industries INC | Oak Creek | Methyl isobutyl ketoneHealth riskEye, skin, and respiratory irritant; central-nervous-system depressant at high exposure. (NIOSH) | 999k lb | +69% |
| Charter Steel-SaukvilleCharter Manufacturing Co INC | Saukville | Zinc compoundsHealth riskGenerally low acute toxicity. Chronic high-dose exposure disrupts copper absorption and immune function. (ATSDR) | 894k lb | +16% |
| Waupaca Foundry Plant 2/3Monomoy Capital Partners LLC | Waupaca | Zinc compoundsHealth riskGenerally low acute toxicity. Chronic high-dose exposure disrupts copper absorption and immune function. (ATSDR) | 825k lb | -36% |
| Weston Power PlantWec Energy Group | Mosinee | Barium compounds (except for barium sulfate (CAS No. 7727-43-7))Health riskSoluble barium compounds are toxic if ingested, affecting the heart, kidneys, and nervous system. Insoluble forms (e.g. barium sulfate) are far less toxic. (EPA) | 658k lb | -12% |
| Packaging Corp Of Ameri CaPackaging CORP Of America | Tomahawk | MethanolHealth riskAcutely toxic if ingested or inhaled. Metabolizes to formaldehyde and formic acid, causing blindness and metabolic acidosis. (EPA) | 580k lb | +7% |
| Neenah Foundry CO Neenah OperationsNeenah Foundry Co | Neenah | Zinc (fume or dust)Health riskGenerally low acute toxicity. Chronic high-dose exposure disrupts copper absorption and immune function. (ATSDR) | 494k lb | -15% |
| Ahlstrom Na Specialty Solutions LLCAhlstrom USA INC | Kaukauna | MethanolHealth riskAcutely toxic if ingested or inhaled. Metabolizes to formaldehyde and formic acid, causing blindness and metabolic acidosis. (EPA) | 441k lb | -3% |
Water utilities to watch
Largest Water Systems With Unresolved Health-Based Violations
Sorted to surface utilities serving the most people that still have an active health-based SDWIS violation on the record. Systems in compliance with no unresolved issues fall to the bottom of the ranking.
| Water system | PWSID | Population served | Health-based · 5yr | Status |
|---|---|---|---|---|
| Madison Water Utility Municipal | WI1130224 | 272,000 | 2 | UNRESOLVED |
| Waukesha Water Utility Municipal | WI2680238 | 70,718 | 315 | UNRESOLVED |
| Sun Prairie Utilities Municipal | WI1130258 | 33,966 | 3 | UNRESOLVED |
| Oak Creek Waterworks Municipal | WI2410172 | 32,104 | 1 | UNRESOLVED |
| Brookfield Water Utility Municipal | WI2680253 | 29,070 | 2 | UNRESOLVED |
| Superior Water Light & Power Company Private | WI8160147 | 26,084 | 1 | UNRESOLVED |
| Middleton Waterworks Municipal | WI1130242 | 23,868 | 1 | UNRESOLVED |
| Caledonia Water Utility - Village Of Municipal | WI2520184 | 21,819 | 1 | UNRESOLVED |
| Howard Waterworks Municipal | WI4050468 | 21,133 | 4 | UNRESOLVED |
| Germantown Water Utility Municipal | WI2670105 | 20,027 | 1 | UNRESOLVED |
Superfund / NPL sites
Federal Cleanup Sites In Wisconsin
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 |
|---|---|---|---|---|
| Algoma Municipal Landfill | Algoma | 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) |
| Amcast Industrial Corporation | Cedarburg | NPL FINAL | No | 1,1'-Biphenyl |
| Ashland/Northern States Power Lakefront | Ashland | NPL FINAL | No | 1,2,4-Trichlorobenzene |
| Better Brite Plating Co. Chrome And Zinc Shops | De Pere | 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) |
| City Disposal Corp. Landfill | Dunn | NPL FINAL | No | 1,2-Dimethylbenzene (O-Xylene) |
| Delavan Municipal Well #4 | Delavan | NPL FINAL | No | TetrachloroetheneHealth riskPCE / 'perc'. IARC Group 2A probable carcinogen; central-nervous-system effects; common dry-cleaning solvent and DNAPL plume contaminant. EPA MCL 5 µg/L. (IARC, EPA) |
| Hagen Farm | Stoughton | 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) |
| Hechimovich Sanitary Landfill | Mayville | NPL FINAL | No | 1,2-DichloroethaneHealth riskIARC Group 2B possible carcinogen; liver and kidney toxic. EPA MCL 5 µg/L. (IARC, EPA) |
| Hunts Disposal Landfill | Caledonia | 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) |
| Janesville Ash Beds | Janesville | 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) |
Showing the top 10 sites by status priority. 36 additional NPL-relevant sites in Wisconsin have entity pages — browse them via the host-county or host-city page rollups.
Equity context · ACS 2018-2022 · USEPA-clone EJ disparity
Statewide Population Characteristics
All Wisconsin block groups: 5,893,718 residents. Statewide disparity score for pm2.5 (fine particulate) sits well below the reference (44). Why we surface this →
State-level percentiles are aggregated from block-group EJScreen data. The EJ pattern within the state will be sharper at the county level — drill down for the meaningful spatial detail.
10.7%
Low-income
20.1%
People of color
5.9%
Under age 5
17.7%
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.41near the national median
- OzoneHealth riskGround-level ozone (smog) inflames the airways. Even short exposures trigger asthma attacks and worsen chronic lung and heart disease.68above 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.55near 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.41near 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.90in the highest 10% 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.85in the highest 20% nationally
- 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.69above 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.78above the national median
- 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.74above 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.61above 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.71above 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.65above 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.93in the highest 10% nationally
| Indicator | Disparity score | Reading |
|---|---|---|
| PM2.5 (fine particulate) | 44 | well below the reference |
| Ozone | 48 | well below the reference |
| Nitrogen dioxide (NO₂) | 56 | below the reference |
| Diesel particulate | 44 | well below the reference |
| Toxic releases (RSEI) | 60 | below the reference |
| Traffic proximity | 62 | below the reference |
| Lead-paint risk (pre-1960 housing) | 58 | below the reference |
| Superfund site proximity | 45 | well below the reference |
| RMP-facility proximity | 57 | below the reference |
| Hazardous-waste site proximity | 51 | below the reference |
| Underground storage tanks | 54 | below the reference |
| NPDES wastewater proximity | 28 | well below the reference |
| Drinking-water non-compliance | 34 | well below the reference |
Source: Census ACS 2018-2022 (5-year) + USEPA-clone EJ blockgroup stats (raw indicators + EJ disparity mirror). EJ disparity scores via the USEPA-clone GitHub mirror after EPA deprecated the public EJScreen tool in 2025; demographics from Census ACS.
Browse
All 63 Wisconsin Counties With TRI Data
Pollution trends and TRI 2024 pages for every tracked county. Alphabetical.
- Adams County pollution· 2 facilities
- Barron County pollution· 10 facilities
- Bayfield County pollution· 1 facility
- Brown County pollution· 45 facilities
- Buffalo County pollution· 1 facility
- Burnett County pollution· 2 facilities
- Calumet County pollution· 9 facilities
- Chippewa County pollution· 7 facilities
- Clark County pollution· 6 facilities
- Columbia County pollution· 14 facilities
- Crawford County pollution· 2 facilities
- Dane County pollution· 37 facilities
- Dodge County pollution· 19 facilities
- Door County pollution· 2 facilities
- Douglas County pollution· 5 facilities
- Dunn County pollution· 8 facilities
- Eau Claire County pollution· 10 facilities
- Fond du Lac County pollution· 12 facilities
- Grant County pollution· 6 facilities
- Green County pollution· 8 facilities
- Iowa County pollution· 1 facility
- Jackson County pollution· 1 facility
- Jefferson County pollution· 16 facilities
- Juneau County pollution· 5 facilities
- Kenosha County pollution· 15 facilities
- Kewaunee County pollution· 2 facilities
- La Crosse County pollution· 11 facilities
- Lafayette County pollution· 1 facility
- Langlade County pollution· 2 facilities
- Lincoln County pollution· 4 facilities
- Manitowoc County pollution· 20 facilities
- Marathon County pollution· 30 facilities
- Marinette County pollution· 9 facilities
- Marquette County pollution· 1 facility
- Milwaukee County pollution· 76 facilities
- Monroe County pollution· 4 facilities
- Oconto County pollution· 5 facilities
- Oneida County pollution· 3 facilities
- Outagamie County pollution· 24 facilities
- Ozaukee County pollution· 10 facilities
- Pierce County pollution· 4 facilities
- Polk County pollution· 3 facilities
- Portage County pollution· 9 facilities
- Price County pollution· 1 facility
- Racine County pollution· 21 facilities
- Richland County pollution· 2 facilities
- Rock County pollution· 15 facilities
- Rusk County pollution· 1 facility
- Sauk County pollution· 14 facilities
- Sawyer County pollution· 3 facilities
- Shawano County pollution· 5 facilities
- Sheboygan County pollution· 24 facilities
- St Croix pollution· 3 facilities
- Trempealeau County pollution· 5 facilities
- Vernon County pollution· 3 facilities
- Vilas County pollution· 1 facility
- Walworth County pollution· 17 facilities
- Washington County pollution· 19 facilities
- Waukesha County pollution· 44 facilities
- Waupaca County pollution· 9 facilities
- Waushara County pollution· 1 facility
- Winnebago County pollution· 23 facilities
- Wood County pollution· 13 facilities
Sources.
- EPA Toxics Release Inventory · retrieved 2026-05-07.