New Study Identifies Over 57,000 Sites Presumptively Contaminated” with PFAS

A new paper from Northeastern University’s PFAS Project Lab and researchers from the National Institute of Environmental Health Sciences (NIEHS) reaches the sobering conclusion that over 57,000 sites in the U.S. have "presumptive contamination" from per- and polyfluoroalkyl substances (“PFAS”). Even more sobering is the authors' assertion that that number is almost certainly a dramatic underestimation of the number of PFAS-contaminated sites, given limited data availability and the conservative mapping methodology employed.

Released on October 11th, the paper, “Presumptive Contamination: A New Approach to PFAS Contamination Based on Likely Sources” (published in Environmental Science & Technology Letters), aims to fill existing data gaps by positing that

[I]n the absence of high-quality data to the contrary, PFAS contamination is probable near facilities known to produce, use, and/or release PFAS, and to protect public health, the existence of PFAS in these locations should be presumed until high-quality testing data is available.
Building on existing research, test data, and environmental reporting, the authors contend that PFAS contamination can be presumed at three types of facilities:

(1) Fluorinated aqueous film-forming foam ("AFFF") discharge sites: military sites, airports, firefighting training sites, and "high-hazard flammable liquid fire" sites such as those associated with oil and gas extraction, petroleum refineries, bulk storage facilities, and chemical manufacturing, as well as railroad crashes.

(2) Industrial facilities that produce or use PFAS: Identified largely through the limited scope of facilities that reported PFAS use under the U.S. Environmental Protection Agency ("EPA") Toxic Release Inventory ("TRI") program.

(3) Sites related to PFAS-containing waste: Including PFAS-contaminated effluent and sludge from wastewater treatment plants ("WWTPs"), as well as solid waste disposal sites.

Using mapping technology, the study identified 57,412 sites of "presumptive PFAS contamination" in the United States, including 49,145 industrial facilities, 4,255 WWTPs, 3,493 military sites, and 519 major airports. The sites are identified in the publicly available PFAS Contamination Site and Community Resources map, available at

The authors note that "State and federal agencies can use a presumptive contamination approach to identify and prioritize locations for monitoring, regulation, and remediation."

The information from this study is particularly notable on the heels of EPA's August 2022 proposal to add two PFAS chemicals (PFOA and PFOS) to the list of hazardous substances under the Superfund program. Clearly, the magnitude of PFAS contamination in the United States is extraordinary, and raises the potential for thousands of clean up actions (and regulatory enforcement) at sites across the country.