In 2016, the Federal Health Advisory (HAL) Drinking Water Guidance Levels for PFOS and PFOA were reduced to 70 Parts Per Trillion (PPT). Also in 2016, Suffolk County Water Authority tested a well located approximately 2 miles southeast of the airport on Church Street. The tests contained results above the HAL for PFOS and PFOA. In January 2018 the Town was notified by NYSDEC that the airport would be designated as a potential inactive hazardous waste disposal site – Class “P”, following the 2016 detection of PFOS in those wells.

In February 2019, the Town Board passed a resolution to enter into an Order on Consent with NYSDEC to conduct a site characterization to determine if contamination is present in soil or groundwater at the airport. On the same date, the Town Board passed a resolution to engage Arcadis Inc. for environmental services and expanded site inspection (Records Research – 2019 and Site Characterization Work Plan-2020). This work was approved by NYSDEC on April 16, 2020. A Site Characterization Report was prepared by Arcadis and submitted to NYSDEC in December 2022.

While this investigative work by the Town and review of drinking water standards by EPA and the New York State Department of Health has been underway, the Suffolk County Water Authority, working with all of these agencies, has installed protective carbon filtering systems at its drinking water wells to block the entry of PFAS and PFOA into the drinking water supply. These activities have been taking place at many airports and other sites across the state where the use of aqueous firefighting foam and other releases of PFAS and PFOA has been documented.

The designation of MacArthur Airport as a State Superfund Site in February 2023 opens the next “remediation” phase of the effort to protect the public health from these chemical compounds. In January 2024 the Town expects to approve the execution of a new Consent Order with the NYSDEC to perform a Remedial Investigation/Feasibility Study (RI/FS) for the airport. This Order will not only make the Town eligible for grant funding to help perform the RI/FS, but will advance the effort to not only identify, but implement, a final management solution.

The Remedial Investigation phase will come first. This will build upon the Site Characterization already performed to gain a precise, three-dimensional understanding of the location and concentration of contaminants in the soil. The following phase will be a Feasibility Study to determine the most effective and practical management methods to control and remove the identified contaminants. That phase will draw upon the results of similar studies at other sites, and the recommendations of EPA, NYSDOH, NYSDEC and SCWA as these agencies collaborate to share experience and techniques. The final phase will be the assembly of a Record of Decision, open to public comment, for the selection of a final remedial mitigation program to be undertaken by the Town, with the assistance of other agencies.

The answer to the environmental threat of PFAS/PFOA and other “forever chemicals” will require a collaborative effort of federal, state and local governments. You may follow the progress of Islip’s efforts on the Town website via this page.