PFAS: Forever Chemicals

The per-and polyfluoroalkyl substances (PFAS) are a group of man-made chemicals used to make coatings used in consumer products that resist heat, oil, stains, grease, water, and can act as a fire retardant. The group of chemicals has been in use since the 1940's. 

These coatings, also known as fluoropolymer coatings, can be in a variety of products like clothing, furniture, adhesives, food packaging, heat-resistant non-stick cooking surfaces, and the insulation of electrical wire.  

PFAS are widely used, long lasting chemicals that break down very slowly over time. They are often called “forever chemicals”. 

Many PFAS are a concern because they: 

• Do not break down in the environment
• Can move through soils and contaminate drinking water sources
• Build up, or bioaccumulate, in fish and wildlife 

Tucson is one of the largest remaining groundwater systems in the country.  Tucson's groundwater supply is contained in a U.S. Environmental Protection Agency (USEPA) designated sole source aquifer, meaning that Tucson does not have immediate access to surface water from lakes, streams, or rivers making any contamination of the aquifer a critical issue for Tucson’s water supply. 

In 2009, the City of Tucson made the decision to voluntarily test local groundwater supplies and launched the Sentry Program. The City of Tucson and Tucson Water's goal was to maintain the integrity of the aquifer by going above and beyond state and federal regulatory requirements for water quality.  At that time, PFAS concentrations were detected in some areas but were below health advisory limits. As the health advisory limits became more stringent, Tucson Water restricted the use of the water where PFAS was detected, ensuring that the water delivered to customers remained safe and reliable. 

Coordinated efforts with the Arizona Department of Environmental Quality, the U.S. Environmental Protection Agency, and other local water providers to address PFAS in the region continue to occur.  

In tandem with proactive, widespread testing at all drinking water system entry points, Tucson Water is also removing PFAS from the groundwater at the Advanced Oxidation Process Water Treatment Facility/ Tucson Airport Remediation Project located near I-19 and Irvington and is working with the Arizona Department of Environmental Quality on additional water treatment remediation sites.  

Wells in the Tucson Water service area with PFAS detections are not in service to customers. 

The USEPA sets Maximum Contaminant Levels (MCLs) for PFAS and most recently updated MCL thresholds in April 2024. Tucson Water has implemented its own operational standards above and beyond these enforceable USEPA MCLs as listed below.

Tucson Water will continue to take actions to ensure our drinking water exceeds the EPA’s requirements and to protect our customers and our long-term water supply. Here’s a glimpse of some of the actions taken to date: 

• Removed almost 30 production wells from service that previously contributed to drinking water system 
• Invested in specialized laboratory equipment for our state certified water quality laboratory so that we can analyze over 1,800 samples for PFAS each year 
• Removed Tucson Airport Remediation Project (TARP) from connection to the potable system (June 2021) 
• ADEQ announces $25 million investment to improve PFAS treatment in Tucson 
• Biden-Harris Administration to Invest $30 Million to Protect Tucson Residents from PFAS 
• Construction of the Randolph Park Groundwater Treatment Facility

Tucson Water has been and continues to be proactive about water quality, including PFAS, because we care about customers and our community. We are Tucsonans working for Tucson. 

Explore recommendations from the USEPA to avoid other exposures to PFAS and learn how Tucson Water is working with ADEQ to achieve a PFAS-free future. 

The National Institute of Health (NIH) has more information about how people are exposed to PFAS, current research, government coordination efforts, and additional reading and resources.