A team of environmental science consultants told the East Hampton Town Board on Tuesday that groundwater contamination beneath the now-capped Springs-Fireplace Road landfill is slowly diminishing, as expected. However, as the board noted, ongoing testing of private wells across a wide swath of the industrial corridor surrounding the old landfill demonstrate elevated levels of manganese and nitrates.
During the presentation, which also included data on the former Montauk landfill, one Springs resident insisted that the consultants were downplaying the danger of contaminated drinking water.
Benjamin Cancemi, the FPM Group’s (Fanning, Phillips and Molnar) hydrogeology department manager, summarized the findings: “Since capping operations have gone into place, we’re seeing conditions improve dramatically,” he said. “We submit these reports regularly to the state, the state reviews them, and there’s no concerns regarding the monitoring results.”
Supervisor Peter Van Scoyoc noted, however, that the Suffolk County Health Department has tested 184 of 514 private wells surrounding the capped landfill and commercial composting or mulching operations along the Springs-Fireplace Road corridor, and that the survey, which the department described as precautionary, has to date revealed 23 detections of nitrates above the drinking water standard and six detections of manganese above the standard. These, he said, are byproducts of composting facilities.
No volatile organic compounds above drinking water standards have been detected in the private wells surveyed, Mr. Van Scoyoc said. “That tends to reinforce the report that you’ve given here,” he told Mr. Cancemi. Most of the elevated levels of VOCs are “legacy,” he said, referring to past landfill operations. “But I do think we have to be ever-vigilant.”
That last remark echoed earlier ones by Frank Riina of Springs, who said that the consultants, while reporting accurate information, are understating their findings and downplaying the threat to human health posed by VOCs and manganese in groundwater. He said he was “disappointed by the town’s failure to show prudence.” Later in the meeting, he implored the board to examine the Suffolk Health Department’s private well survey “before you say it’s not spreading beyond the landfill.” Manganese levels in groundwater at the landfill “are far beyond anything that could occur naturally,” Mr. Riina asserted.
At the start of the presentation, officials of the FPM Group presented findings of their 2019 fourth-quarter report to the board, part of groundwater monitoring that the firm has conducted since the late 1990s, before the landfill was capped in 2002. “There have been VOC impacts identified from past monitoring, historically,” said Mr. Cancemi, who displayed maps detailing where elevated levels of such compounds have been detected.
VOCs originated and migrated from the “putrescible section” — raw garbage — at two portions of the landfill, Mr. Cancemi said. After the landfill was capped, construction and demolition debris, which he said included a wide variety of substances, were consolidated on top of the putrescible section.
VOC levels have decreased since the landfill was capped, Mr. Cancemi said, and are mostly confined to the town-owned landfill property. The only detections above the groundwater standard are near a well on the site, he said, but VOCs may extend north to the East Hampton Golf Club on Abraham’s Path.
Wells monitored along Abraham’s Path show no contamination, he said, with the exception of one near the corner of Springs-Fireplace Road, which has for several years revealed perchloroethylene, PCE, “below groundwater standards and just above the method detection limit for the laboratory,” which he said is around one microgram per liter. “It’s barely detectable, and below the standard,” Mr. Cancemi said.
Detections above groundwater standards at the well on the landfill property are of perchloroethylene, a toxic volatile solvent, cis-1,2DC, and vinyl chloride, a toxic gas. Mr. Cancemi said that the latter two result naturally from perchloroethylene degradation. “It’s doing exactly what one would expect once the landfill is capped and the levels are coming down.” All will continue to diminish, he said.
Levels of manganese have risen over the last few years, mostly on the periphery of the current composting area at the landfill, Mr. Cancemi said. “It appears the current composting operations are showing some impacts to groundwater at certain locations.” Elevated levels of manganese, which he described as a naturally occurring compound in “the organic matrix,” were detected within the landfill site, he said.
Elevated levels of manganese occur naturally in some groundwater on Long Island, Mr. Cancemi said, but the State Department of Environmental Conservation, Councilman Jeff Bragman noted, “is concerned about composting’s impact on groundwater. This is a big new area of concern for them.”
There has not been detection of methane at the landfill for at least 10 years, Mr. Cancemi said.
At the former landfill in Montauk, levels of ammonia rose after it was capped almost 20 years ago, “but now we’re starting to see a decreasing trend,” Mr. Cancemi said. Ammonia indicates nitrogen levels, “a natural component of landfill leachate” — liquid that has dissolved or drawn in and transported harmful substances as it flowed. Ammonia remains above the groundwater standard at the site, but is diminishing over time, “as one would expect once the landfill was capped.”
The concentration of sodium in the groundwater has increased, he said, suggesting a relationship to previous storage of salt at the site. Mr. Van Scoyoc and Stephen Lynch, the superintendent of highways, both said that salt is not stored there, though Mr. Van Scoyoc allowed that it could have been in the past.
The discussion took place alongside one about draft legislation that would require the owner of any mining or composting facility to submit a work plan for monitoring of groundwater impacts to the town’s Department of Natural Resources.
Stephanie Davis of FPM discussed the legislation, which the town board plans to add to the code. It is enabled by a state law passed in 2018, allowing municipalities to enact and enforce laws requiring groundwater monitoring for mines and composting facilities where sole-source aquifers are the primary water supply. “As you know, we are all drinking groundwater from sole-source drinking water aquifers, and that’s really the impetus for this,” Ms. Davis said.
The intent of a local law, she said, “is to protect the resources, to identify impacts to it, and remediate and address them as effectively as possible. It’s not to punish people as much as it is to just ensure we’re going to have safe drinking water for generations to come.”
Following a lengthy discussion of the proposed legislation’s parameters, Mr. Van Scoyoc said that the board would deliberate before further consultations with the FPM Group, ultimately crafting a law and scheduling a public hearing.