February 20, 2024 9:41 AM

PFAS Detected in Two City of Prescott Wells

The City of Prescott tests its drinking water supply regularly to ensure that it meets all drinking water quality standards.  Recent test results found the presence of man-made chemicals called Perfluoriooctanoic acid (PFOA) and Perfluorooctane sulfonate (PFOS) in two of its water production wells located in the airport area.  While PFOA and PFOS are not currently regulated by the US Environmental Protection Agency (EPA) nor the Arizona Department of Environmental Quality (ADEQ), emerging scientific thought is that these compounds may be harmful to human health.  Results of sampling for these two wells showed levels of PFOA as high as 15 parts per trillion (ppt) and PFOS as high as 12 ppt, which is greater than the temporary advisory levels given by the EPA and ADEQ.  

What Is the City Doing?

Immediately upon receiving test results that were greater than the recommended Health Advisory Levels (HALs) of 0.004 ppt for PFOA and 0.02 ppt for PFOS, the City shut down water production at the two affected well sites.  The City will promptly investigate the possible source(s) of the PFOA/PFOS. The affected wells will not be put back into service until they meet the recommended Heath Advisory Levels established by the EPA and ADEQ.   

What Does this Mean? 

PFAS such as PFOA and PFOS are a group of manufactured chemicals that have been used in industry and consumer products since the 1940s because of their useful properties.  PFAS can be present in our water, soil, air, and food as well as in materials found in our homes or workplaces.  PFAS can break down very slowly and can build up in people, animals, and the environment over time.

Will the Shut Down of the Two Wells Affect Water Service?

The City operates a total of 8 wells located in and around Prescott.  There will be no noticeable difference in water delivery to any customers.

What Should I Do?

There is no immediate health risk.  You DO NOT need to use an alternative water supply since the affected wells are no longer in use.  However, if you have specific concerns, please consult your doctor.

For more information about PFOA or PFOS, please visit the City website at https://www.prescott-az.gov/water-sewer/water-operations/water-quality-reports/  or contact City of Prescott Public Works Department – Water Division at 928-777-1118.   

For information about the EPA Health Advisory and ADEQ actions, follow these links: 

Arizona Department of Environmental Quality (ADEQ)

Environmental Protection Agency (EPA)

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