HURLEY — The closed town of Hurley landfill in Ulster County has been added to the state’s registry for Superfund sites, which will allow the town to access more than $1 million of state remediation funds to clean up PFOS and PFOA contamination at the site.

A public notice issued by the state Department of Environmental Conservation announced the site’s Superfund classification, urging anyone living near the inactive landfill at 1043 Dug Hill Road to be aware. The list it was added to — the state’s Registry of Inactive Hazardous Waste Disposal Sites — is maintained by a DEC program for identifying, investigating and cleaning up sites where disposed hazardous waste may present a threat to public health and/or the environment.

The landfill was categorized as “Class 02,” meaning it presents a “significant threat to public health and/or the environment,” in this case, because of PFOS and PFOA contamination.

Perfluorooctane sulfonic acid (PFOS) is one group of thousands of related chemicals known as perfluorinated alkylated substances (PFAS). The toxic chemicals are long-lasting and break down very slowly over time. They are commonly used in a wide range of industrial processes and found in many everyday consumer items, including food.

The U.S. Environmental Protection Agency says scientific studies have shown exposure to some PFAS in the environment may cause harmful health effects in people and animals. Though it has been known for years that exposure to PFAS is harmful, researchers still do not fully understand how to remove them from drinking water, the full extent of how harmful they are to humans, how much people are exposed to the chemicals and how to better and more efficiently detect them in the air, water, soil, fish and wildlife.

PFOA and PFOS have been detected at the Hurley landfill on-site groundwater monitoring wells, in a leachate collection tank, in surface water and sediment samples adjacent to the site, as well as in private drinking water wells downgradient of the site, according to the public notice of its Superfund classification.

Additional investigation is needed to define the nature and extent of site-related contamination, to evaluate associated human exposure pathways, and to determine the appropriate actions to prevent and mitigate potential exposures, according to the public notice.

“We were expecting this,” Hurley Supervisor Melinda McKnight said of the Superfund designation in a news release issued Thursday. She noted the contamination dates to when the landfill operated — from the 1960s to the mid-1990s — but that the presence of PFOS wasn’t known until after the state started testing for it in 2018.

An engineering report on the landfill’s conditions that was discussed by the town earlier this year led to questions about the possible pollution of nearby wells caused by lack of maintenance, according to Hudson Valley One. An engineer said the landfill’s original construction was an issue — that waste was deposited directly on the bedrock without a liner, according to the news story. A liner is used in a landfill as a protective layer between waste and the environment and helps with leachate collection. Without it, waste can seep into the ground and contaminate the soil and groundwater.