Unregulated Contaminant Monitoring Rule (UCMR)
Egyptians drinking water
Under the 1996 amendments to the federal Safe Drinking Water Act, the U.S. Environmental Protection Agency is required once every five years to issue a new list of up to 30 unregulated contaminants for which public water systems must monitor. The intent of this rule is to provide baseline occurrence data that the EPA can combine with toxicological research to make decisions about potential future drinking water regulations. We are currently going through the third round of this contaminant testing.

The most recent UCMR, the Third Unregulated Contaminant Monitoring Rule (UCMR3), was signed by former EPA Administrator Lisa P. Jackson on April 16, 2012. The EPA, the states, laboratories and public water systems all participated in the testing for UCMR3 in various ways. The testing occurred between January 2013 and December 2015.
The contaminants that were monitored under UCMR3 included:
Seven Volatile Organic Compounds
  • trichloropropane
  • butadiene
  • chloromethane (methyl chloride)
  • bromomethane (methyl bromide)
  • chlorodifluoromethane (HCFC-22)
  • bromochloromethane (halon 1011)
One Synthetic Organic Compound
  • dioxane
Six Metals
  • vanadium
  • molybdenum
  • cobalt
  • strontium
  • chromium
  • chromium 6 (hexavalent chromium)
One Oxyhalide Anion
  • chlorate
Six Perfluorinated Compounds
  • perfluorooctanesulfonic acid (PFOS)
  • perfluorooctanoic acid (PFOA)
  • perfluorononanoic acid (PFNA)
  • perfluorohexanesulfonic acid (PFHxS)
  • perfluoroheptanoic acid (PFHpA)
  • perfluorobutanesulfonic acid (PFBS)
Seven Hormones
  • estradiol
  • ethynylestradiol (ethinyl estradiol)
  • hydroxyestradiol (estriol)
  • equilin
  • estrone
  • testosterone
  • 4-androstene-3,17-dione
Two Viruses
  • Enteroviruses
  • Noroviruses
It is likely that your water provider participates in UCMR testing in some capacity. All public water systems serving more than 10,000 people, 800 representative PWSs serving 10,000 or fewer people, and 800 representative PWSs serving 1,000 or fewer people participated in some portion of the UCMR3 testing. The testing occurred between January 2013 and December 2015. You can contact your local water provider to ask about its participation in UCMR testing.
This most recent round of testing helped determine whether or not certain contaminants are found in drinking water, at what levels they are found, and in which parts of the country.

The most recent round of testing ended December 2015. Depending on how prevalent the contaminants were and at what levels they were found, EPA may conduct further research to determine whether or not to begin regulating some or all of them.

In December 2015 EPA proposed a new list of analytes to be monitored in the next round of UCMR beginning in 2018.