Middlesex Water’s $52M plant to treat ground water for PFAS compounds now in service

Middlesex Water Co. recently said that construction of an upgraded treatment plant at its Park Avenue wellfield in South Plainfield — to treat Perfluorooctanoic Acid, or PFOA — is now completed and the plant is in service. It is treating groundwater in compliance with all state and federal drinking water standards.

In 2021, the New Jersey Department of Environmental Protection adopted a new Maximum Contaminant Level for one of the more prevalent per- and polyfluoroalkyl substances, or PFAS, compounds, PFOA. While the drinking water delivered by Middlesex met all existing regulatory standards at the time, when the new MCL became effective, the Park Avenue plant initially exceeded the new PFOA standard. The company suspended use of the wellfield once it was able to switch to alternate sources of supply in November 2021. These alternate sources of supply helped ensure water delivered, from that time forward, was in compliance with all drinking water standards.

By June 2022, due to an expedited, phased construction approach, Middlesex Water was able to begin successfully treating groundwater containing PFOA in compliance with the new standard through a partial and temporary treatment facility.

This interim facility also helped Middlesex meet heightened seasonal water consumption demands. As of June 30, the facility has progressed from temporary to permanent treatment status and is treating groundwater in compliance with all drinking water standards.

New Jersey’s standard for PFOA is 0.014 parts per billion and is among the most stringent standards in the nation. The 0.014 ppb is based on a running annual average, in which the four most recent quarters of monitoring data are averaged. Middlesex’s RAA for PFOA at the Park Avenue facility is currently at a level that is non-detectible under current analytical technology.

“I am deeply appreciative of our internal engineering and operations teams and external consultants who worked together to address this issue so effectively and efficiently. Our company did not place PFOA into the groundwater, yet we’re committed to protecting public health and, as such, are required to expend significant funds and labor resources to remove it to comply with standards,” Dennis Doll, chairman, CEO and president, said. “We are grateful to the New Jersey Department of Environmental Protection for their counsel as we navigated the design, construction, operationalization and public communication relative to our treatment facility, which continue to be comparable challenges for water systems in many states.”

Middlesex Water is currently in litigation with the firm it believes is responsible for the PFOA contamination. A trial date is set for Oct. 2 in the U.S. District Court for the District of New Jersey in Newark.