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How EPA Regulates Drinking Water Contaminants Documents

The Safe Drinking Water Act (SDWA) defines a water contaminant as any physical chemical, biological, or radiological substance or matter in water. The law charges EPA to set legal limits on the levels of certain contaminants in drinking water.

CFR Part 141 National Primary Drinking Water Regulations (pdf) (1.02 MB)
CFR Part 142 National Primary Drinking Water Regulations Implementation (pdf) (328.68 KB)
CFR Part 143 National Secondary Drinking Water Regulations (pdf) (167.95 KB)