In May 2021, state officials discovered that an underdrain carrying groundwater away from the state’s only landfill — which empties into nearby water bodies — was contaminated with PFAS, a class of chemicals that are harmful to human health. Casella, the company that owns the Coventry landfill, has submitted a plan, in the form of an amendment to their operating permit, to address the contamination.
The underdrain carries between 4,000 and 13,000 gallons of groundwater per day from beneath the landfill and away from the facility toward the Black River, which drains into Lake Memphremagog, a drinking water source for more than 175,000 Canadians. The permit amendment is separate from another PFAS-related pilot project Casella is working on that would take PFAS out of its leachate, the liquid waste from the landfill.
Leachate is currently treated at the Montpelier wastewater treatment facility before being discharged into the Winooski River, which eventually empties into Lake Champlain. The wastewater treatment facility doesn’t take PFAS out of the leachate. State officials have been sorting through a bevy of public comments about the pilot project, and haven’t yet finalized that permit.