ST CHARLES COUNTY PWSD 2

O'FALLON, MO · ~100,587 people served

Check your exact address → O'FALLON overview

100

Excellent

PurityRadar safety score

PWSID

MO6024530

State

Missouri

City

O'FALLON

Population served

100,587

Primary source

SWP

Score history

No change since tracking began Jun 18, 2026.

Jun 18, 2026 · score 100 Jun 18, 2026 · score 100

2 score updates logged since tracking began Jun 18, 2026. Each future EPA re-score adds a point.

PFAS & contaminant readings

Latest detections from EPA’s UCMR5 monitoring (through Jan 2025). Levels in parts per trillion (ppt).

Lithium

31,200 ppt

limit —

No federal limit

PFBA

5.2 ppt

limit —

No federal limit

Violations & enforcement

Violations on record

Unaddressed

Health-based

Enforcement actions

From EPA ECHO (SDWIS), most recent enforcement Sep 2025. Official EPA record →

Monitoring & reporting · EPA contaminant 0700 began Jun 2025 Resolved

Monitoring · Lead & Copper Rule began Jun 2021 Resolved

Max contaminant level (MCL) · Total coliform health-based began Sep 2007 Resolved

Max contaminant level (MCL) · Total coliform health-based began Dec 1996 Resolved

Recent enforcement actions

State action · SOX Sep 2025
State action · SIF Aug 2025
State action · SIA Jul 2025
State action · SIE Jul 2025
State action · SIF Jul 2022
State action · SOX Jul 2022
State action · SIA Aug 2021
State action · SIE Aug 2021

Area water-quality monitoring

Environmental monitoring (rivers, wells, intakes) recorded in this system’s service area in the EPA/USGS Water Quality Portal since 2018 — source/ambient water, not finished tap water. Context for the watershed, not a reading from your tap.

ContaminantMedian · max · samples

Nitrate

8 stations · latest Sep 2024

0.013 · max 1.04 mg/L · 144

Source: Water Quality Portal (EPA/USGS/state agencies). Values are as-reported and aren’t health thresholds.

This profile is built from EPA public records for system MO6024530 — SDWIS violations and UCMR5 PFAS sampling. The score is system-level and can’t account for your home’s plumbing (older pipes can add lead at the tap). For health decisions, check your exact address, read the utility’s Consumer Confidence Report, and confirm with your provider.