Source document
South Holland, IL 1992 Consumer Confidence Report
The original annual drinking-water report. Every number on the South Holland, IL water quality page is pulled from this document.
The South Holland, IL figures for 1992 come from EPA's national Safe Drinking Water database (SDWIS / ECHO) — not a single utility-published PDF. Every value on the South Holland, 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