Public Notice of Availability and Request for Comment
Draft Environmental Assessment for Westchester County Airport: Million Air Redevelopment / Development Project
View the public notice of availability.
Airport PFAS Investigation and Remediation Program
On June 6, 2019 Westchester County (the County) and the New York State Department of Environmental Conservation (NYSDEC) executed an Order on Consent (CO3-20180308-44) due to concerns related to perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) identified in groundwater on the Westchester County Airport (Airport). The airport is classified as a “P-site” in the NYSDEC database. The P-site designation means that, based on preliminary information, the Airport and surrounding area appear to be impacted requiring site characterization. The chemicals of concern at the site are per- and polyfluoroalkyl substances (PFAS). PFAS are a group of man-made chemicals that includes PFOA, PFOS, as well as many other chemicals. PFAS are reported to be very persistent in the environment and can accumulate in the human body. PFAS in groundwater at airports is primarily linked to the use of firefighting foams at airports. Although no promulgated regulatory remediation standards have been developed for PFAS for various environmental media (i.e. soil, groundwater or sediment), the NYSDEC views PFAS as a deleterious chemical that requires site characterization.
On May 19, 2016, USEPA issued a lifetime health advisory level of 70 parts per trillion (ppt) for long-term exposure to PFOA and PFOS in drinking water. On July 30, 2020 the Governor of New York announced maximum contaminant levels for PFOA and PFOS in New York's drinking water of 10 ppt. The NYSDEC’s position regarding PFAS and other non-PFAS chemicals at the Site was memorialized in its letter to the County dated March 20, 2019.
Based on the preliminary findings at the site, the NYSDEC is requiring that further site characterization activities be completed to determine the nature and extent of PFAS contamination previously identified at the Site. Additionally, NYSDEC is requiring the County to further investigate other areas of the site to confirm the presence or absence of additional PFAS source areas. NYSDEC has also required the investigation of potential sources of other Target Compound List/Target Analyte List (TCL/TAL) of chemicals (e.g., volatile and semi-volatile compounds, pesticides, Polychlorinated Biphenyls (PCBs), and metals).
The deliverables associated with the Site Characterization Work Plan include monthly progress reports, due on or before the tenth day of the month; summarizing the prior month’s and projecting the future month’s activities; and a final report is required in connection with each Work Plan that is implemented by the County.
The County is also involved in surface water and groundwater Interim Remedial Measures (IRMs) for PFOS and PFOA.
2019-2020"Site Characterization" and "IRMs" work plans and monthly progress reports follow.
Site Characterization Report Westchester County Airport (PFAS)