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Monitoring Unregulated Drinking Water Contaminants

List of Laboratories Approved by EPA for the Fourth Unregulated Contaminant Monitoring Rule (UCMR 4)

This document provides a list of laboratories that met the fourth Unregulated Contaminant Monitoring Rule (UCMR 4) laboratory approval program application and proficiency testing criteria for the methods indicated.

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EPA Approved Laboratories for UCMR 4 (PDF)(18 pp, 865 K, January 2018, 810-B-18-001)