Source document
Oak Park, IL 1994 Consumer Confidence Report
The original annual drinking-water report. Every number on the Oak Park, IL water quality page is pulled from this document.
The Oak Park, IL figures for 1994 come from EPA's national Safe Drinking Water database (SDWIS / ECHO) — not a single utility-published PDF. Every value on the Oak Park, IL water quality page is transcribed from that public dataset, and you can verify it against the same source below.
View the source dataset ↗https://echo.epa.gov/tools/data-downloads/sdwa-download-summary