Skip to main content
U.S. flag

An official website of the United States government

Radium in Groundwater Study Area - Cambrian-Ordovician Aquifer

Detailed Description

Concentrations of radium in samples of untreated groundwater from the confined parts of the Cambrian-Ordovician groundwater system frequently exceeded the USEPA maximum contaminant level of 5 picocuries per liter in Illinois, Iowa, and eastern Wisconsin, where wells tap deeper, older groundwater.


Public Domain.