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Monitoring Unregulated Drinking Water Contaminants

Fact Sheets about the Fourth Unregulated Contaminant Monitoring Rule (UCMR 4)

These fact sheets provide background information and contaminant list informaton about the fourth Unregulated Contaminant Monitoring Rule (UCMR 4).

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UCMR 4 Basic Information Fact Sheet (PDF)(2 pp, 151 K, December 2016, 815-F-16-007)
General background information for UCMR 4.
UCMR 4 Fact Sheet for Assessment Monitoring - Cyanotoxins (PDF)(3 pp, 323 K, December 2016, 815-F-16-008)
UCMR 4 Fact Sheet for Assessment Monitoring - Haloacetic Acid (HAA) (PDF)(3 pp, 335 K, December 2016, 815-F-16-006)
UCMR 4 Fact Sheet for Assessment Monitoring - Additional Contaminants (PDF)(3 pp, 168 K, December 2016, 815-F-16-009)