PWSID
IL1630350
State
Illinois
City
DUPO
Population served
4,684
Primary source
Groundwater
Score history
▼ 11 points — the score moved from 100 to 89 on Jun 18, 2026, as newly published EPA data was incorporated.
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 Nov 2025). Levels in parts per trillion (ppt).
PFOS
Perfluorooctanesulfonic acid
4.5 ppt
limit 4 ppt
PFHxS
Perfluorohexanesulfonic acid
3.1 ppt
limit 10 ppt
Lithium
23,000 ppt
limit —
PFBS
3.7 ppt
limit —
Violations & enforcement
2
Violations on record
0
Unaddressed
0
Health-based
4
Enforcement actions
From EPA ECHO (SDWIS), most recent enforcement Oct 2024. Official EPA record →
Recent enforcement actions
- State action · SOX Oct 2024
- State action · SIA Oct 2024
- State action · SOX Aug 2019
- State action · SIA Jul 2019
This profile is built from EPA public records for system IL1630350 — 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.