Environmentalists opposed to the expansion of a Northeast Kingdom landfill say Vermont is being inconsistent in how it regulates the landfill鈥檚 wastewater.
At issue is leachate 鈥� the chemical brew created when water seeps through mountains of trash.
A state environmental commission recently allowed a division of Casella Waste Systems but with one key restriction.
Opponents from the group Memphremagog Conservation Inc. argued successfully that Coventry landfill leachate, which the advocates like to call should no longer be sent to the Newport sewage treatment plant, since it eventually ends up in Lake Memphremagog.
The state commission noted of Canadians, who should be protected from exposure to leachate chemicals.
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But in Vermont and around the country, other sewage treatment plants still routinely accept leachate, including one in Montpelier.
The capital city鈥檚 sewage treatment plant sits near the confluence of the Dog River and the Winooski River. And that鈥檚 where the treated wastewater goes 鈥� out into the Winooski, and eventually into Lake Champlain. Included in that waste stream is leachate from the Coventry landfill and a closed landfill in Moretown.
On a hot afternoon in August, Kurt Motyka, the city鈥檚 assistant public works director, pointed out some metal-covered tanks on one side of the plant.
鈥淭he one nearest to us is for leachate storage," he said. "It鈥檚 about a 30,000 gallon tank. And we bleed in 30 gallons per minute of leachate into the effluent stream coming into the plant."
The Montpelier plant handles many pollutants in untreated sewage, like pathogens and like nutrients such as phosphorus and nitrogen.
But as with most other sewage treatment plants, it鈥檚 not set up to process some of the more dangerous compounds of leachate. These are the so-called and other related compounds. They are the by-products of many common household products or industrial processes. They鈥檝e shown up in 鈥� and they're leaching out of landfills.
The Coventry leachate gets the same treatment in Montpelier as the other stuff in the waste stream. But Motyka said the plant is not designed to treat PFAS.
"They're really very, very small levels [of PFAS]. And that's what's directly leaving the plant, and then you dilute it into the Winooski and Lake Champlain." 鈥� Kurt Motyka, Montpelier assistant public works director
The Winooski River flows into Lake Champlain. And just like Lake Memphremagog, Lake Champlain is a drinking water supply for hundreds of thousands of people.
State tests last year showed the PFAS levels released from the Montpelier plant were below 70 parts per trillion, the EPA鈥檚 limit for drinking water. But they were above Vermont鈥檚 stricter standard of 20 parts per trillion.
鈥淭hey鈥檙e really very, very small levels,鈥� he said. 鈥淎nd that鈥檚 what鈥檚 directly leaving the plant, and then you dilute it into the Winooski and Lake Champlain. They are low levels, but it is obviously a concern for many people and definitely worth investigating treatment alternatives.鈥�
Environmentalists argue that even at low levels, the family of PFAS chemicals can pose a health risk.
鈥淯nfortunately with these contaminants, the levels that are safe for human exposure are in the parts per trillion,鈥� said Elena Mihaly, a lawyer for the Conservation Law Foundation in Montpelier who worked on the Coventry case.
鈥淪o this is one of those contaminants that talking about diluting is not the answer to the health risks posed,鈥� she said.
"Unfortunately with these contaminants, the levels that are safe for human exposure are in the parts per trillion." 鈥� Elena Mihaly, lawyer for Conservation Law Foundation
Mihaly said there is a fundamental disconnect between barring leachate from going into one water supply but allowing it in another. A sewage plant in Plattsburgh, New York also handles Coventry leachate, and that also goes into Lake Champlain.
鈥淲hen you look at the remaining waste water treatment facilities that are currently authorized to accept that leachate, they all discharge into drinking water sources,鈥� she said. 鈥淪o it鈥檚 illogical that the [state environmental] commission would rule one way, citing a significant risk to drinking water, and not see that same risk when the water is flowing from the Montpelier waste plant into the Winooski River and into Lake Champlain."
Coventry produces a lot of leachate. In 2018, Montpelier handled almost six million gallons of the stuff from that landfill alone.
Casella is operating under a 2011 permit that lets it send the leachate to the sewage plants. Kasey Kathan, an analyst with Vermont's Department of Environmental Conservation, said that鈥檚 not unusual.
鈥淭he management of leachate at wastewater treatment facilities is kind of standard best management practice in the country,鈥� she said.
Kathan said unless there鈥檚 some known industrial source of PFAS in the landfill waste, landfills are rarely required to treat leachate on site.
"The management of leachate at wastewater treatment facilities is kind of standard best management practice in the country." 鈥� Kasey Kathan, state environmental analyst
However, the state wants Casella to look at alternative treatment methods, and a study is due in October. The state is also doing its own study into PFAS and leachate treatment. Both that study and the one Casella has underway will be used to inform a new leachate discharge permit for the Coventry landfill.
As for the disconnect that the environmentalists point to between one treatment plant being allowed to handle it, while another is prohibited, Kathan said that may be because the research hasn鈥檛 been done to show alternatives.
Mihaly from the Conservation Law Foundation said it鈥檚 premature to allow leachate into wastewater plants without knowing if there will soon be a better way to handle it.
鈥淭he problem here is that we鈥檙e putting the cart before the horse a little bit ... before we have the results back from investigations that are going on into what is the safest way to treat it,鈥� she said.
"Our primary objective is clean water. Leachate is added revenue for the city, but the goal of this facility is to produce clean water, so that's always the primary focus." 鈥� Kurt Motyka, Montpelier assistant public works director
At the Montpelier Water Resource Recovery Facility, Kurt Motyka said he's eager to learn more about better ways to treat leachate and remove PFAS chemicals. In the meantime, the treatment plant earns the city about $300,000 a year from accepting Coventry landfill's leachate, money that鈥檚 especially useful as the plant is undergoing a $16 million upgrade.
鈥淥ur primary objective is clean water,鈥� Motyka said. 鈥淟eachate is added revenue for the city, but the goal of this facility is to produce clean water, so that鈥檚 always the primary focus."
