Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

JavaScript appears to be disabled on this computer. Please click here to see any active alerts.

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

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

UCMR 4 Basic Information Fact Sheet (pdf) (December 2016, 815-F-16-007)
General background information for UCMR 4.
UCMR 4 Fact Sheet for Assessment Monitoring - Cyanotoxins (pdf) (December 2016, 815-F-16-008)
UCMR 4 Fact Sheet for Assessment Monitoring - Haloacetic Acid (HAA) (pdf) (December 2016, 815-F-16-006)
UCMR 4 Fact Sheet for Assessment Monitoring - Additional Contaminants (pdf) (December 2016, 815-F-16-009)