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Monitoring the Occurrence of Unregulated Drinking Water Contaminants

EPA collects data for chemicals and microbes that may be present in drinking water, but are not currently subject to EPA drinking water regulations. Learn about the Unregulated Contaminant Monitoring Rule.

About Monitoring Unregulated Drinking Water Contaminants

Current and Previous UCMRs

Laboratory Approval

(Ongoing) UCMR 5 Laboratory Approval Program

Occurrence and Reporting Data

The Safe Drinking Water Act requires that EPA monitor for no more than 30 unregulated contaminants every five years.

Important Dates for UCMR 5

January 15, 2021 – Laboratory Approval Program starts for UCMR 5.
January 15, 2021 – Ground Water Representative Monitoring Plan Program starts for UCMR 5.
April 6 and 7, 2021 – Public webinar meeting on Revisions to the Unregulated Contaminant Monitoring Rule for the Fifth Monitoring Cycle (UCMR 5)

Related Information