New York River Watch, a coalition of clean water advocates, called on the New York State Department of Environmental Conservation on 15 August 2026 to strengthen a proposed rule requiring active landfills to pretreat leachate before it reaches municipal sewage plants, citing a report that more than 500 million gallons of landfill leachate flowed to publicly owned treatment works each year from 2019 to 2023, with one-third ultimately discharged to waterways used as drinking water sources Yahoo.
Key takeaways
- New York River Watch reported in August 2026 that more than 500 million gallons of leachate per year were sent to municipal sewage plants from 2019 to 2023, with one-third discharged to drinking-water source waterways Yahoo.
- DEC's draft rule would require active landfills to pretreat leachate for PFOA, PFOS and 1,4-dioxane, but would exempt inactive landfills and those closing within two years of finalization Yahoo.
- About half of the leachate reaching New York waterways came from landfills run by WM, Waste Connections and Casella Waste Systems, according to the New York River Watch report Yahoo.
- DEC projected in supporting documents that 25 active municipal solid waste landfills and seven active construction-and-demolition debris landfills would be covered by the proposal Waste Dive.
- Operators told DEC that specialized leachate treatment facilities could cost $3 million to $50 million to build, with annual operating costs of about $1.5 million to $8 million Waste Dive.
What happened
The push comes as DEC moves to finalize what would be the first state rule to specifically require landfill operators to treat leachate for contaminants, with a public comment period that closed on 9 September and a public hearing held on 2 September Waste Dive. Under the proposal, landfill operators would need to develop a leachate treatment plan within one year of the rule becoming effective, while wastewater facilities would have four years to continue receiving leachate as landfills transition to more advanced treatment systems Waste Dive.
New York River Watch's report argues that responsibility for contaminant management should move upstream from publicly owned treatment works to landfill operators and, eventually, to chemical manufacturers, because many sewage plants are not equipped to handle the wide range of contaminants in leachate, particularly when raw leachate is also high in organic material Yahoo. Pat Byrne, an analyst at Bluefield Research, said that "if you try and treat really high organic material water with that stuff, it's going to mess up that adsorptive capacity, and your costs go through the roof" Yahoo. Rebecca Martin, executive director and co-founder of New York River Watch, said the largest private operators "should bear some responsibility for this before the state just opens up the coffers and gives pilots or grants or public funds for these private companies to develop treatment facilities with technologies that are really new" Yahoo.
Industry response has been sharply critical. The National Waste and Recycling Association, along with WM, Waste Connections and Casella, argued during the public comment process that a 99.9% removal requirement for a wide range of contaminants could approach the limits of detection and that any rules should be based on contaminant-specific research and available treatment technology Waste Dive. WM cited state studies in Michigan and North Carolina that found average leachate contributions of PFOS, PFOA and 1,4-dioxane ranged from 0.3% to 10.2% of total contaminant presence, averaging 3.3%, arguing that landfill leachate is a relatively small share of PFAS reaching wastewater systems Waste Dive. Sam Nicolai, Casella's vice president of engineering and compliance, told the hearing that "this is an extraordinarily expensive and wasteful approach to leachate management and a missed opportunity to develop a well-coordinated approach to PFAS" Waste Dive.
Local officials and landfill operators proposed a regional model, in which centrally located facilities handle leachate from multiple landfills, to keep costs down and avoid duplicating infrastructure Waste Dive. The EPA has signaled it plans to update its landfill Effluent Limitation Guidelines, last revised in 2000, which could tighten federal requirements for contaminants passing from landfill leachate to public waterways Yahoo. New York River Watch is also asking DEC to extend the comment period and to include inactive landfills, citing a 2024 DEC study that found PFOA and PFOS above drinking-water standards in groundwater at 68% of the state's closed landfills Yahoo.
Specification read
The reported 500 million gallons per year of leachate sent to municipal plants in New York from 2019 to 2023 equates to roughly 5,200 m³/day averaged across the state, with the one-third share discharged to drinking-water source waterways at about 1,750 m³/day; on a per-landfill basis that lands in the low thousands of m³/day range for a typical active MSW site, which is the class of project that drives pretreatment train sizing. The DEC proposal is aimed squarely at the front end of that train, at screening and pretreatment for PFOA, PFOS and 1,4-dioxane before the leachate ever reaches a publicly owned treatment works, rather than at biological or tertiary stages typically used for municipal sewage. For a municipal or private operator whose plant receives landfill leachate in the 500 to 5,000 m³/day range with high organic loading and PFAS-driven compliance pressure, this rule signals that on-site or regional advanced treatment, likely using carbon adsorption or reverse osmosis, will have to be specified and costed alongside the existing headworks, with capital estimates that DEC has placed in the $3 million to $50 million range and operating costs of $1.5 million to $8 million per year. Engineering interpretation, including the flow conversion, is general industry practice; the cost figures and target contaminants come from the sources.
FAQ
What is the DEC actually proposing to require?
DEC is proposing the first state rule that would specifically require active landfill operators to pretreat leachate for PFOA, PFOS and 1,4-dioxane before sending it to a publicly owned treatment works, with affected operators needing a leachate treatment plan within one year of the rule's effective date Waste Dive.
How many landfills would the rule cover and what could it cost?
DEC's supporting documents estimate 25 active MSW landfills and seven active C&D debris landfills would be affected, with DEC projecting treatment facility capital costs of $3 million to $50 million and annual operating costs of about $1.5 million to $8 million per facility Waste Dive.
Which treatment stages are most likely to be specified for a compliant landfill leachate plant?
Based on the source materials, on-site treatment would target advanced removal of PFAS and 1,4-dioxane using processes such as granular activated carbon and reverse osmosis, sized after upstream municipal headworks; the high organic load in raw leachate is expected to foul adsorptive media and drive up operating cost, so equalization and biological pretreatment are typical pre-stages (general industry range, not from the sources).
What is the current regulatory status and next milestone?
DEC's public comment period closed on 9 September 2026 following a 2 September hearing, and the agency is now reviewing comments; the EPA has also signaled it plans to update its landfill Effluent Limitation Guidelines, last revised in 2000 Yahoo Waste Dive.
