The Town of Frisco sent out a letter to Frisco water customers on Friday, November 18, 2022, to provide them with the latest information and updates regarding the progress on treatment options for Well 7, where PFAS substances were found during voluntary testing of water samples. The Town last sent out communications in July 2022 to inform water customers that the Environmental Protection Agency had issued interim, updated drinking water health advisories for PFAS substances, which advised that levels of two PFAS substances be brought to below detectable levels; basically to zero. While this was only an advisory and not a requirement, the Town subsequently decided to stop pulling water for the general water supply from Well 7, one of four Town water sources, and to continue working on treatment design for Well 7.
Well 7 Background and Progress
- All three rounds of voluntary testing in 2020 and 2021 showed that one water source, Well 7 (first used as a water source in March 2018), had combined levels of PFOA and PFOS between 17.2ppt (parts per trillion) and 16ppt; at that time, those levels were well below the EPA health advisory for these substances, which was then 70ppt and above for PFOA and PFOS combined. In July 2022, the EPA revised their health advisory recommending that PFOA and PFOS levels be at below detectable levels- close to zero.
- In 2021, the Town made the decision to voluntarily pursue and budget for a design of a PFAS water treatment system for Well 7, despite the levels being well below the EPA health advisory levels at that point.
- In July 2022 after receiving a revised health advisory from the EPA recommending levels below detectable limits, Frisco decided to stop pulling water from Well 7, as infrastructure improvements to other Town water sources had just been completed, and to continue working through treatment design. Well 7 is still not being used as a water source and will remain offline as long as conditions allow and until the PFAS treatment system is installed. In addition, water customers would be informed if Well 7 is ever needed in the general water supply before PFAS treatment can be installed.
- December 2022, Frisco Water is scheduled to start a three-month pilot test at Well 7 to assess two treatment options, a granular activated carbon filtration process and an ion exchange resin filtration process. These are the best treatment options available at this time and have been rigorously vetted by the Town’s engineering partner. During this assessment and pilot testing period, water from Well 7 will not be in the general water supply and will be contained to Well 7, where the testing will occur.
- In 2023, the Town of Frisco expects to install a PFAS treatment system on Well 7. This will necessitate an expansion of the Well 7 building to house whichever treatment process is found to be most effective in bringing all PFAS levels to below detectable levels during the pilot test.
The Town will continue to take every step possible to ensure that Frisco’s water is of the highest quality. Treatment and well shutdown were not advised or required in response to voluntary PFAS testing, and the Town still took steps to take Well 7 offline and plan for PFAS treatment.
Please expect to receive more of these updates regarding PFAS treatment at Well 7, as the Town reaches milestones in this process. To find out more about Frisco’s Water, please visit FriscoWater.com or reach out to us with your questions and feedback at WaterInfo@townoffrisco.com and 970-668-9153.