The vast majority of Vermont’s trash meets its end at a large landfill in Coventry, the only operating landfill in the state. Leachate — liquid waste from the landfill — is currently treated at a single wastewater facility in Montpelier. In late April, after discovering levels of E. coli in the plant’s effluent that violated its permit, officials at the Montpelier facility stopped accepting leachate from the Coventry landfill. From then until now, Casella, the company that owns the landfill, has been trucking most of the leachate produced in the state to Plattsburgh, New York, and the rest to Franklin, New Hampshire.
Chris Cox, chief operating officer at Montpelier’s Water Resource Recovery Facility, said he’s not sure when the city will be able to accept leachate again. His team is working with Casella and the consulting engineering firm Brown and Caldwell to determine the source of the problem. On April 20, Cox said officials found E. coli levels of 190 colony forming units (CFU) per 100 milligrams, and the permitted limit is 77 CFU. That level remains below what the state considers safe for swimming, which is 235 CFU, Cox said.
Montpellier’s facility uses ultraviolet light to sterilize effluent before it’s released into the Winooski River, which is part of the Lake Champlain watershed. It seems that a material present in the leachate hindered the effectiveness of the ultraviolet light, Cox said, adding that a material may have absorbed or reflected the light, shielding the E. coli and possibly other bacteria and pathogens. E. coli is an indicator organism, Cox said, meaning that “if you can really prove that you’re killing E. coli, you’re beyond certain that you’re killing viruses and pathogens that are killed a lot easier than E. coli.”