Superfund / NPL site · EPA Superfund SEMS through latest publishNPL Final

Washington County Lead District - Potosi

This site is currently on the EPA Superfund National Priorities List and remains under federal cleanup oversight. Most-cited contaminant of concern: Arsenic.

500 Ft East Of Bell St And Valley Road, Potosi, Missouri · ZIP 63664 · EPA ID MON000705023

CLEANUP TIMELINE

Listing-date and cleanup-phase enrichment from EPA's per-site SEMS profile is queued for a follow-up ingest pass. Until then, this section will populate from EPA's published timeline data.

Anomaly engine

Notable Signals

No notable signals at this Superfund site for the current ingest. Cleanup-phase and SEMS-action flags are deferred to a follow-up engineering pass.

Contaminants of concern · per EPA SEMS

What's In This Site

Each row pairs a contaminant with the medium it was found in (the exposure pathway). Hover any named contaminant for an agency-cited health-risk summary. Cited count = number of SEMS decision records (RODs and related) that name the pair.

ContaminantPathwayCited
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)Groundwater1
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)Soil1
BariumHealth 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)Groundwater1
CadmiumGroundwater1
LeadHealth riskNeurotoxin. Even low childhood exposure impairs cognitive development; chronic adult exposure damages kidneys and the cardiovascular system. (EPA, ATSDR)Groundwater1
LeadHealth riskNeurotoxin. Even low childhood exposure impairs cognitive development; chronic adult exposure damages kidneys and the cardiovascular system. (EPA, ATSDR)Soil1
Drinking-water linkage · SDWIS

Groundwater Systems Serving Communities Within 3 Miles

The 3 systems below draw on groundwater (or mixed sources) and serve communities whose centroid sits within 3 miles of this site. Distance is to the served-city centroid — SDWIS does not expose individual wellhead locations, so this is a proximity screen, not a wellhead-impact assessment.

Water systemServesDistancePopulation servedSourceStatus
Potosi Pws MunicipalPotosi0.5 mi2,527GROUNDWATERUNRESOLVED
Potosi East State-ownedPotosi0.5 mi900GROUNDWATERUNRESOLVED
Mineral Point Pws MunicipalMineral Point2.6 mi231GROUNDWATERUNRESOLVED

Methodology: served-city centroid (TIGER 2020) is used as the PWS coordinate. Source-water classification from SDWIS primary_source_code; only groundwater and mixed-source systems are queried. Click any system above for its full SDWIS profile.

Equity context · ACS 2018-2022 block-group demographics

Who Lives Near This Site

Within 1 mile of this site (1 Census block groups, population-weighted demographics): a population of 4,797. Why we surface this →

POPULATION SHARE
42.9%

Low-income

POPULATION SHARE
13.5%

People of color

POPULATION SHARE
5.4%

Under age 5

POPULATION SHARE
13.3%

Over age 64

Source: Census ACS 2018-2022 block-group demographics, population-weighted across the 1-mile buffer around this site (from USEPA-clone/EJAM-open blockgroupstats). NPL site proximity contributes to the national EJ pattern; indicator-level percentile and disparity scores are surfaced on the county page and the state page.

Source. EPA Superfund Enterprise Management System (SEMS) · retrieved 2026-05-07. SEMS is a federal public-domain dataset under 17 USC §105.

What this is not. We report EPA's published Superfund record — site listing, status, and contaminants of concern as named in EPA's decision documents. We do not perform site visits, independent air or water sampling, or current-state health-risk assessment. NPL listing reflects EPA's Hazard Ranking Score at a point in time; it does not by itself describe present-day exposure.