The Massachusetts Department of Environmental Protection has approved Hopkinton’s activation of the full-scale PFAS treatment system at Well 6, Department of Public Works Director Kerry Reed announced in a statement Friday.

“The system is in operation, and cleaner water is flowing to users,” Reed stated.

This water treatment system is designed to remove per- and polyfluoroalkyl substances known as PFAS to levels reliably and consistently below the current MassDEP and EPA Maximum Contaminant Levels (MCL).

PFAS levels in water have been an ongoing concern for the town, which prompted the remediation effort. Known as “forever chemicals,” these synthetic, potentially harmful chemicals used since the 1940s can be found in a wide variety of household products and industrial processes.

While the effects of PFAS still are being studied, the Environmental Protection Agency found that exposure to certain levels of PFAS may be harmful to children and pregnant or lactating women.

MassDEP notified the town on June 27 of its approval to activate the temporary full-scale PFAS treatment system. The decision was made after personnel from the Central Regional Office of the MassDEP on June 13 conducted an activation inspection. This approval is good until July 1, 2027, or until Hopkinton is interconnected into the Massachusetts Water Resources Authority (MWRA) water system.

In the absence of an interconnection to MWRA, the temporary PFAS treatment system will need to be converted to a permanent water treatment plant that fully complies with all permits, regulations, guidelines and policies.

The Water Department will operate the PFAS filtration system and monitor water treatment, according to Reed. Sampling will be conducted in accordance with regulatory requirements, and sampling results will continue to be available to the public.

The bottled water rebate program will remain in effect until the town determines that it is no longer necessary, Reed added.

Reed thanked MassDEP as well as the project team for its work. The project team consists of the Hopkinton Water Department, consultant Weston & Sampson and Bay State Regional Contractors, Inc.

Additional information is available on the Water Department website.