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Inorganic Chemicals: Water Quality Testing

For questions about Water Quality,
call (608)266-4654,
email: water@cityofmadison.com

EPA SAFE DRINKING WATER HOTLINE
1-800-426-4791,
Web: epa.gov/safewater

 
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Inorganic chemicals (IOCs) include salts, metals, minerals and nutrients that can be naturally occurring or can result from storm water runoff, waste water discharges or farming activities. In a sandstone aquifer, significant amounts of naturally occurring minerals are dissolved in the water. These dissolved minerals account for “hardness” in Madison's water (averaging approximately 355 parts per million as calcium carbonate, or 21 grains of hardness).