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Six-Year Review of Drinking Water Standards

The Safe Drinking Water Act (SDWA) requires EPA to review each national primary drinking water regulation at least once every six years and revise them, if appropriate. As part of the "Six-Year Review," EPA evaluates any newly available data, information and technologies to determine if any regulatory revisions are needed. Revisions must maintain or strengthen public health protection.

Contaminant Occurrence in Drinking Water

What Contaminants are Currently Regulated?