BANGOR DAILY NEWS • September 5, 2025
Casella Waste Systems is closing its Hawk Ridge Compost Facility in Unity Township after Maine regulators discovered high levels of forever chemicals on the site and indications that the contamination may have spread to the land around it. For almost four decades, Hawk Ridge, the state’s largest composting facility, has accepted millions of gallons of sewage sludge and turned it into compost used in Maine and beyond. The test results and Casella’s response show the pervasive nature of the chemicals and the difficulty in crafting Maine’s pioneering effort to regulate them. Casella submitted its closure proposal to the DEP in late August. It includes no longer accepting sludge as of Sept. 1 and removing all materials from the site, cleaning it and closing by June 30, 2026. Casella would pay for the closure, a DEP spokesperson said.