Environmentalists opposed to the expansion of a Northeast Kingdom landfill say Vermont is being inconsistent in how it regulates the landfill’s wastewater.
At issue is leachate – the chemical brew created when water seeps through mountains of trash.
A state environmental commission recently allowed a division of Casella Waste Systems to expand Vermont’s only open landfill by 51 acres, but with one key restriction.
Opponents from the group Memphremagog Conservation Inc. argued successfully that Coventry landfill leachate, which the advocates like to call "garbage juice," should no longer be sent to the Newport sewage treatment plant, since it eventually ends up in Lake Memphremagog.
The state commission noted Memphremagog is a drinking water supply for hundreds of thousands of Canadians, who should be protected from exposure to leachate chemicals.
More from VPR: Canadian Opponent To Coventry Landfill: 'We're Just Getting The Leachate' [July 30]
But in Vermont and around the country, other sewage treatment plants still routinely accept leachate, including one in Montpelier.
The capital city’s sewage treatment plant sits near the confluence of the Dog River and the Winooski River. And that’s where the treated wastewater goes – 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.
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On a hot afternoon in August, Kurt Motyka, the city’s assistant public works director, pointed out some metal-covered tanks on one side of the plant.
“The one nearest to us is for leachate storage," he said. "It’s 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’s not set up to process some of the more dangerous compounds of leachate. These are the so-called contaminants of emerging concern, PFOA, PFASand other related compounds. They are the by-products of many common household products or industrial processes. They’ve shown up in groundwater in Vermont and all over the country – 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." — 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’s limit for drinking water. But they were above Vermont’s stricter standard of 20 parts per trillion.
“They’re really very, very small levels,” he said. “And that’s what’s 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.”
Environmentalists argue that even at low levels, the family of PFAS chemicals can pose a health risk.
“Unfortunately with these contaminants, the levels that are safe for human exposure are in the parts per trillion,” said Elena Mihaly, a lawyer for the Conservation Law Foundation in Montpelier who worked on the Coventry case.
“So this is one of those contaminants that talking about diluting is not the answer to the health risks posed,” she said.
"Unfortunately with these contaminants, the levels that are safe for human exposure are in the parts per trillion." — 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.
“When you look at the remaining waste water treatment facilities that are currently authorized to accept that leachate, they all discharge into drinking water sources,” she said. “So it’s 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’s not unusual.
“The management of leachate at wastewater treatment facilities is kind of standard best management practice in the country,” she said.
Kathan said unless there’s 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." — 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’t been done to show alternatives.
Mihaly from the Conservation Law Foundation said it’s premature to allow leachate into wastewater plants without knowing if there will soon be a better way to handle it.
“The problem here is that we’re 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,” 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." — 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’s especially useful as the plant is undergoing a $16 million upgrade.
“Our primary objective is clean water,” Motyka said. “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."
