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Monitoring Unregulated Drinking Water Contaminants

List of Laboratories Approved by EPA for the Third Unregulated Contaminant Monitoring Rule (UCMR 3)

EPA's UCMR 3 Laboratory Approval Program ended in December 2016, coinciding with the end of the UCMR 3 cycle. The list of UCMR 3 labs will remain posted for the foreseeable future to exclusively serve as a reference for interested stakeholders seeking the analytical services of a previously approved UCMR 3 laboratory.  Stakeholders interested in finding a UCMR 4 qualified laboratory should not use this table as a reference, but rather review the current list of EPA approved laboratories for UCMR 4.

This document provides a list of laboratories that met the third Unregulated Contaminant Monitoring Rule (UCMR 3) laboratory approval program application and proficiency testing criteria for the methods indicated.

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