UCMR4 Analysis

UCMR4 Logo

What is UCMR4?

January 2018 marks the start of the USEPA’s Unregulated Contaminant Monitoring Rule 4 (UCMR4) sampling and analysis period.  All public water supplies (PWS) serving more than 10,000 people are required to monitor for a 12-month period between January 2018 and December 2020.

Population will be based on size of system as of December 31, 2015.  EPA selects the nationally representative sample of small systems serving 10,000 or fewer as well.

Monitoring Requirements

The UCMR4 final rule requires PWSs to analyze drinking water for 29 unregulated contaminants and one group of regulated contaminants (HAAs).  The monitoring data may influence future regulatory actions to protect public health.

Click Here for a detailed chart of UCMR4 Testing Requirements for Groundwater, Surface Water and Groundwater Under the Influence of Surface Water Public Water Supplies.


If you are within a 2-3 hour radius of our headquarters, our team of field scientists can provide sampling and transportation services.  If you are outside of that area, no problem!  We are certified to test anywhere in the US.  We can send you easy-to-use sampling kits that you simply ship back to us for analysis.

For UCMR4, sampling will be done at the EPTDS (Entry Point to the Distribution System), except for:

  • HAA’s: Distribution HAA Locations.  Regulated HAAs and UCMR4 HAAs can be collected concurrently to prevent significant burden.
  • TOC & Bromide – SR (Source Water Intake Locations)

Key Reporting Deadlines for PWSs

By December 31, 2017

  • Report Contact Info in SDWARS
  • Review / Revise Sampling Location Info and Monitoring Schedule in SDWARS

After December 31, 2017

  • Notify EPA of any sampling location/inventory changes
  • Notify EPA if unable to sample according to established schedulermation

More information about the UCMR4 program can be found on the EPA’s website: https://www.epa.gov/dwucmr/fourth-unregulated-contaminant-monitoring-rule