Home News and Features City will Keep Accepting PFAS-Reduced Landfill Leachate as Part of Pilot

City will Keep Accepting PFAS-Reduced Landfill Leachate as Part of Pilot

Demonstrators at the Vermont Statehouse on Jan. 30 use a bit of theater to showcase some of the health effects of PFAS in water systems. Photo by Terry Allen.
Montpelier City Council gave its approval for the wastewater treatment plant to continue accepting daily truckloads of pretreated leachate, or “garbage juice,” from the Coventry landfill for at least another six months. 

During that time, landfill operator Casella Waste Systems will continue pilot-testing technology to reduce levels of the per- and polyfluoroalkyl substances (PFAS) family of hazardous “forever chemicals” in the liquid. 

The chemicals, which are linked to numerous health problems and resist environmental breakdown, ooze into the landfill from trashed carpets, furniture, and other everyday items. They are a source of rising concern to regulators. 

“This is cutting-edge across the country right now, what we’re trying to do with this leachate treatment here in Vermont,” Department of Environmental Conservation (DEC) Watershed Division Director Peter LaFlamme told the Council.

“It’s an opportunity to take responsibility,” said District 1 Council member Dona Bate. “We put the same stuff in our landfill … [so] we’re responsible for it.” 

With only District 2 Council Member Tim Heney dissenting, the Montpelier City Council voted to accept the motion near midnight on Wednesday, Feb. 14, wrapping up a marathon meeting. 

Small City, Big Leverage

As the only Vermont municipality currently accepting leachate for treatment, Montpelier holds outsized power over PFAS handling statewide. 

That’s because the ability of state regulators to issue a pretreatment permit — like the proposed one directing Casella to reduce PFAS in leachate — is triggered by the permit allowing leachate to go to Montpelier, LaFlamme told the City Council.

“Should the city of Montpelier decide not to accept leachate from Coventry, then the pretreatment permit goes away, and we don’t have jurisdiction over the landfill,” LaFlamme said.

Mayor Jack McCullough noted that the decision puts Montpelier in a position to influence the environment and environmental regulations beyond the city, “because we’re the linchpin to state regulation. 

“To be a player in improving the environment, not only within Montpelier, but outside of Montpelier — it’s an opportunity we don’t often have,” McCullough added.

“We are probably going to be the first commercial operation of one of these in the entire country, and one of the first landfills treating all of our leachate in the entire country,” said Jeremy Labbe, general manager of the Coventry landfill. “We’re setting the tone for the rest of the country with this.”

Montpelier’s Relationship to Leachate

Montpelier’s Water Resource Recovery Facility has accepted landfill leachate by the truckload for years. It earns revenue from treating the liquid, and the landfill also offers the city reduced rates to treat the solids Montpelier sends back. 

However, wastewater treatment can’t remove PFAS from leachate, so the chemicals wind up discharged to local waterways such as the Winooski River.

Reducing PFAS in local waterways, then, means cutting down on how much arrives at the facility — and leachate is a key target. (PFAS also enter wastewater facilities from residential water customers thanks to their widespread use in consumer goods.)

In late 2021, the City Council called for a halt on accepting the leachate by July 1, 2023 in the absence of pretreatment, and it urged state regulators and Casella to work on ways of reducing PFAS in leachate. Casella began testing pretreatment technology in August 2023, and the deadline was pushed to February 2024. 

The DEC’s draft permit, which it can now go ahead and issue thanks to the City Council’s decision, will give Casella four months to begin a 180-day period of formal pilot testing. The company will collect data on how well its technology reduces levels of the five state-regulated PFAS. Those data will help state regulators create future PFAS-related standards. 

The plan is to set limits on PFAS levels in pretreated leachate for a five-year future permit, explained Amy Polaczyk, the DEC’s Wastewater Program Manager.

The federal Environmental Protection Agency is expected to set federal water standards soon. But those likely won’t be protective enough, Polacyzk said. 

“We’re trying to take this approach to stay ahead of the federal regulations and to be as protective as possible,” Polaczyk said.

How it Works

To reduce PFAS levels in leachate, Casella uses a technology called foam fractionation. The process creates foam, where PFAS tend to collect, then reduces that foam back to liquid form. Doing this repeatedly concentrates the chemicals into a small volume. This concentrated PFAS solution is then bound into cement blocks that are disposed of in the landfill.

Of the five regulated PFAS types, the pretreatment technology reduces levels for four of them by 96% to 99%. Reducing levels of the fifth is proving more difficult, with fluctuating reductions averaging 66%. Samuel Nicolai, vice president of engineering and compliance at Casella, said Casella personnel are working to understand what influences these variations, and they expect to learn more in the coming months.

“That fifth compound is the problem child,” Nicolai said. “Still, we’re very, very pleased with this level of progress and the amount of removal we’re getting, acknowledging that we’ve got to continue to try to find solutions to get that fifth compound a little bit lower.” 

The foam fractionation technology is also adaptable and can be linked to other technologies to improve removal, Nicolai added. (Technologies to totally destroy the chemicals are still “a little bit behind” separation technologies, he said.) 

Downsides to NIMBYing the Leachate

Some council members noted concerns from constituents that the city continues to accept leachate. However, a decision to stop accepting leachate would have several consequences in addition to the loss of state-level regulatory oversight.

Chris Cox, chief operator of the Water Resource Recovery Facility, outlined what the environmental downsides would be. 

“There’s a lot more trucking that goes along with moving the material out of state, so there’s carbon emissions associated with that [and] environmental impacts,” Cox said. “And the majority of the leachate is still going to end up being discharged into Lake Champlain — Plattsburgh is the primary alternate discharge point for leachate for Casella. So it’s hard to see that there’s any environmental gain.”

In addition, Cox said, the city would have a hard time justifying its $1 million pretreatment grant from ARPA if it stopped accepting leachate. Montpelier also earns about $100,000 in annual revenue from accepting and treating leachate. 

In the recent past the city accepted four truckloads of leachate per day, according to Cox, and had four times the revenue from doing so. Now Montpelier accepts one truckload per day, he said.

And if Montpelier refused leachate, Casella would charge the city “market rates” for accepting treated biosolids, or about double what the city currently pays, according to Public Works Director Kurt Motyka. 

That lost discount alone would cost the city roughly a quarter million dollars every year, Motyka said.