On Thursday, January 18, two PFAS filtration tanks were installed at the Fruit Street pump station. Crews from Bay State Contractors were working today to begin connecting the pipes to the pump house. 

When installation is complete, water will flow directly from Fruit Street wells #1, #2 and #6 into the tanks, where it will be processed through a series of filters designed to eliminate PFAS, before being returned to the pump house for distribution into the town water supply. 

PFAS (per- and polyfluoroalkyl substances) are a group of of man-made chemicals that have been manufactured and used in a variety of industries around the globe, including in the United States since the 1940s. Some of the chemicals are very persistent in the environment and in the human body — meaning they don’t break down and they can accumulate over time. There is evidence that exposure to PFAS can lead to adverse human health effects, including liver, blood, thyroid, fetal development and immune systems effects.

A HopNews investigation published in April 2023 revealed that Fruit Street well #6 was likely contaminated by Aqueous Film Forming Foam (AFFF) used by the Massachusetts Fire Academy, who operated a “gas school” at the Fruit Street complex in the 1970’s and early 1980’s. AFFF are synthetic PFAS-containing foams designed for flammable liquid fires. The PFAS serve as surfactants that spread the foam to cool and suppress the fire. While AFFF are extremely effective, they are also a significant source of PFAS pollution.

>> RELATED: Town Water Likely Contaminated by State Fire Academy

In June 2021, the Hopkinton Board of Health issued an advisory for infants, pregnant women, nursing mothers and those who are immunocompromised. The BOH recommended that residents not cook with or drink town water, and instead should use bottled water. The town offers a Bottled Water Rebate Program for affected residents.

The advisory is only for residents using Town water. Homeowners with private wells may also have PFAS in their water supply, but the BOH does not offer private testing.

>> RELATED: How to test your water for PFAS: A step-by-step guide

As of this month, the PFAS levels in well #6 stand at 36.1 part per-trillion (notated as ng/L or nanograms per liter), exceeding the Massachusetts Department of Environmental Protection Maximum Contaminant Level of 20 ng/L. The Department of Public Works is able to reduce the levels of PFAS by blending water from well #1 with well #6, creating a finished water level of 23.7 ng/L, which is still above the maximum state level. Well #2 remains offline for maintenance.

Once the piping is finished, the new filtration tanks will be enclosed in a housing similar to the pump station. The project has experienced delays, but is expected to be completed in late Spring or early Summer.