What is UCMR 5?

The Unregulated Contaminant Monitoring Rule (UCMR) is an initiative by the EPA to monitor public drinking water for the occurrence of specific contaminants. The data collected regarding the exposure and occurrence of these contaminants is used to help improve regulatory decisions that affect public health.

  • The fifth rule was published on March 11, 2021, and includes 30 new chemical contaminants that must be monitored between 2023 and 2025 using specified analytical methods.
  • The Safe Drinking Water Act now requires that UCMR include all large PWSs (serving >10,000 people), all PWSs serving between 3,300 and 10,000 people, and a representative sample of PWSs serving fewer than 3,300 people.
  • Large systems must pay for their own testing, and US EPA will pay for analytical costs for small systems.
  • Labs must receive EPA UCMR approval to conduct analyses on UCMR 5 contaminants.


AEL is an EPA Accredited UCMR 5 Testing Lab and was certified to provide analytical services for the upcoming sampling period (2023-2025). The EPA requires public water systems (PWSs) to use EPA approved laboratories. To receive EPA approval for UCMR 5, laboratories must successfully complete the EPA’s rigorous lab approval program, demonstrating their ability to meet UCMR 5 methods and guidelines.


AEL has EPA approval to conduct UCMR 5 testing using EPA Methods 200.7, 533, and 537.

 No matter what size Public Water Drinking System AEL can help you maintain compliance.