Westborough officials report isolated leak in Fales geothermal system; fluid described as food‑grade, building remains in service

During the superintendent's update the committee heard that a maintenance employee discovered an abnormal pressure condition in one portion of the Fales Elementary geothermal system.

District staff said the system has five circuits; technicians isolated Circuit 1 after testing stabilized the pressure and the district has not needed to add additional heat-transfer fluid since isolating that branch. The presenters said the system is under warranty and that the district engaged the owner's project manager (OPM), the original architect, and the geothermal designer to identify and remediate the fault.

Officials told the committee the fluid used in the closed geothermal loop is propylene glycol and described it as a food‑grade antifreeze used in many school installations; the superintendent said it is considered safe and that neither state reporting requirements nor immediate health restrictions apply. The Board of Health and the Massachusetts Department of Environmental Protection were contacted; the Board of Health will provide a list of abutting neighbors who may have private wells so the district can notify them and offer testing guidance.

District staff said crews will perform on‑site work in February to isolate which well or fitting is leaking (there are five wells in the affected group and 37 total), and presenters said they expect the fault is likely at a fitting near the surface rather than a deep‑well failure. The district emphasized that the building is operating normally with the affected circuit isolated and that, per presenters, ground-source heat and solar systems continue to provide the buildings energy.

The superintendent said a community letter will be sent to give details and invited residents to contact the school committee directly with questions.