In early 2021, the Centerville-Osterville-Marstons Mills (COMM) Water Department in Barnstable, Massachusetts found 30 parts per trillion (ppt) of six types of Per-and polyfluoroalkyl substances (PFAS) in their water source. PFAS are a family of thousands of man-made compounds that are potential hazards to human and ecological health. New state regulations require that if the sum of these “PFAS6” compounds is at or above the Maximum Contaminant Level (MCL) of 20 ppt, then corrective actions by the public water supplier are required. Through a third party, they reached out to Weston & Sampson for assistance with getting the PFAS6 levels below the MCL before the summer tourist season hit and their water demand spiked. They also had very strict financial limitations, so there were constraints on the size and complexity of the treatment system.
We began by reaching out to several treatment vessel manufacturers, looking at both carbon steel and fiberglass reinforced plastic (FRP). We also performed an alternatives analysis, comparing granular activated carbon (GAC) and an ion exchange resin as treatment options. We selected three 4-foot diameter FRP vessels with ion exchange resin, due to the lower time required for the PFAS-contaminated water to be in contact with the media to achieve the treatment goals. This method was both the most cost-effective and most timely, allowing the COMM Water Department to have the system online by the peak summer demand. After we devised and designed the treatment system, our CMR division worked with Clear Creek Systems to install and pipe the entire system together.
The ion exchange treatment system is now fully constructed and COMM has received final approval from the Massachusetts Department of Environmental Protection (MassDEP) to feed the treated water into the distribution system. The COMM Water Department has put the system into full operation, meeting both their financial goals and their need to have the system online to meet both year-round and peak summer demand.
Key Project Features:
- PFAS treatment
- rapid design and deployment
- ion exchange resin