Thallium
Unresolved Lead and Copper Rule violation cited in 2025 (thallium).
1 TRI facilities inside the city limits and 18 public water systems serving residents. In-city TRI releases rose meaningfully year over year (+15%). Toxic releases concentrations are roughly unchanged from 2010.
FIPS 3023125 · population 1,829 · Lewis and Clark County
Unresolved Lead and Copper Rule violation cited in 2025 (thallium).
Unresolved Lead and Copper Rule violation cited in 2025 (thallium).
Unresolved Revised Total Coliform Rule violation cited in 2024 (contaminant 8000).
Unresolved Revised Total Coliform Rule violation cited in 2024 (contaminant 8000).
Showing the 4 most editorially weighted signals out of 10. Lower-severity signals fold into the chemical breakdown and history charts below.
PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) concentrations have fallen 37% since 2010.
PM2.5 24-hour 98th percentile (NAAQS 35 µg/m³ (24-hour)) concentrations have fallen 38% since 2010.
Ozone 8-hour 4th-highest daily max (NAAQS 0.070 ppm (8-hour)) concentrations are up 18% since 2011.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
TRI air releases (5.1 fugitive + 5.2 stack) concentrations are roughly unchanged from 2010.
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 releases volumes here are too small to anchor a multi-year trend; YoY movement is still shown above.
Greenhouse gases (GHGRP large emitters, through 2023) concentrations are up 49% since 2010.
| Facility | Top chemical | Total releases | YoY |
|---|---|---|---|
| American Chemet CorpAmerican Chemet CORP | Copper And Copper CompoundsHealth riskInhaled copper fumes cause metal-fume fever; chronic ingestion above EPA's 1.3 mg/L action level damages the liver. (EPA) | 14k lb | +15% |
50 unresolved violations on the SDWIS record across utilities serving this city.
Utilities serving
Population served
Health-based · 5yr
Unresolved
| Water system | PWSID | Population served | Health-based · 5yr | Status |
|---|---|---|---|---|
| Broadwater Estates Hoa Private | MT0004697 | 40 | 5 | UNRESOLVED |
| Mcdonald Trailer Ct Private | MT0000402 | 75 | 2 | UNRESOLVED |
| East Helena City Of Municipal | MT0000196 | 2,114 | 1 | UNRESOLVED |
| Bahny Brae Subdivision Private | MT0003196 | 35 | 1 | UNRESOLVED |
| Skyview Water And Sewer Utility Private | MT0004039 | 400 | 2 | Returned to compliance |
Showing the 5 systems with recorded health-based or unresolved violations. 13 additional systems are in compliance with no recorded health-based violations in the past 5 years and are not individually tabulated.
A public water systemis the regulated entity, not the city. EPA's SDWIS definition covers anything serving 25+ people for 60+ days a year or with 15+ service connections — that includes municipal utilities (City of Stockton), water districts, mobile home parks operating their own wells, schools, and small private subdivisions. Each system is independently monitored. Some systems serve multiple cities; some cities are served by many systems.
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 | Status | Federal facility | Primary contaminant |
|---|---|---|---|
| East Helena Site | NPL FINAL | No | LeadHealth riskNeurotoxin. Even low childhood exposure impairs cognitive development; chronic adult exposure damages kidneys and the cardiovascular system. (EPA, ATSDR) |
East Helena, Montana (Census place block groups): 1,829 residents. City disparity score for pm2.5 (fine particulate) sits well below the reference (3). Why we surface this →
Low-income
People of color
Under age 5
Over age 64
| Indicator | Disparity score | Reading |
|---|---|---|
| PM2.5 (fine particulate) | 3 | well below the reference |
| Ozone | 87 | below the reference |
| Nitrogen dioxide (NO₂) | 97 | near the reference |
| Diesel particulate | 21 | well below the reference |
| Toxic releases (RSEI) | 26 | well below the reference |
| Traffic proximity | 34 | well below the reference |
| Lead-paint risk (pre-1960 housing) | 70 | below the reference |
| Superfund site proximity | 129 | moderately above the reference |
| RMP-facility proximity | 54 | below the reference |
| Hazardous-waste site proximity | 66 | below the reference |
| Underground storage tanks | 93 | near the reference |
| NPDES wastewater proximity | 117 | moderately above the reference |
| Drinking-water non-compliance | 117 | moderately above the reference |
Source: Census ACS 2018-2022 (5-year) + USEPA-clone EJ blockgroup stats (raw indicators + EJ disparity mirror).
Modeled adult-prevalence estimates published by CDC PLACES, paired with this city's pollution and demographic context. Comparisons are ecological, not causal — pollution and disease prevalence covary at the area level, but the data does not attribute any individual's diagnosis to local exposure. How this section works →
CDC PLACES · 2025 release · BRFSS 2022-2023
CDC PLACES · 2025 release · BRFSS 2022-2023
CDC PLACES · 2025 release · BRFSS 2022-2023
CDC PLACES · 2025 release · BRFSS 2022-2023
CDC PLACES · 2025 release · BRFSS 2022-2023
PLACES uses BRFSS-modeled small-area estimates, not individual records. Crude prevalence shown above is the local rate as published; comparators are age-adjusted vs the Montana mean and the US mean — both population-weighted across counties — so geographies with different age structures stay apples-to-apples. Sources: CDC PLACES · 2025 release · BRFSS 2022-2023.
Sources.