Middlesex Water tells board PFAS rule changes force treatment upgrades, picks granular activated carbon

Middlesex Water told the Highland Park board that new federal and state PFAS drinking‑water standards are driving a substantial treatment upgrade at their Carl J. Olson (CJO) facility, and that the company selected granular activated carbon (GAC) contactors after an extensive pilot program. Brian Carr, vice president and head of engineering, said the firm tested multiple removal techniques and found GAC contactors the most effective and cost‑efficient for the plant’s raw water.

Carr explained the operational implications: the contactor vessels are large (the witnesses used the image of a deep contactor to describe scale), and media changeouts require deliveries and removals of spent carbon. "We tested 6 different techniques...the most effective and most cost effective was the granular and activated carbon deep bed contactors," Carr said. He and other witnesses told the board the state/federal timeline is firm enough that Middlesex intends to begin compliance steps in 2028 and be in compliance by April 2029. The company described media reactivation—spent carbon shipped back to a manufacturer kiln for reactivation—and a roughly one‑year useful life for each tank’s media, staggered so changeouts occur regularly without taking the plant offline.

Board members used this testimony to judge public‑interest justification for the variances. The treatment need was presented as the principal driver for the project and a key reason why the board should weigh benefits to the system alongside local impacts.