Just two days after the U.S. Environmental Protection Agency issued its Notice of Proposed Rulemaking to establish legally enforceable drinking-water levels for six per- and polyfluoroalkyl substances (PFAS), reported by ELM here, the New York State Department of Environmental Conservation released final ambient water quality guidance values for PFOA, PFOS, and 1,4-Dioxane in New York State waters.
In a March 15 press release the DEC said “[t]he finalized guidance values support the State’s ongoing efforts to protect public health and the environment and prevent exposure to emerging contaminants through the protection of drinking water sources.” Furthermore, Commissioner Basil Seggos commented that “[f]inalization of the water quality guidance values keeps New York State as a national leader in regulating PFOA, PFOS, and 1,4-Dioxane in surface water and groundwater…”
The final guidance values, with regard to human health, are 6.7 parts per trillion for PFOA, 2.7 parts per trillion for PFOS, and .35 parts per billion for 1,4-Dioxane. The values will “initially be incorporated into requirements for industrial discharges needing a DEC State Pollutant Discharge Elimination System (SPDES) permit, reducing facilities’ potential contribution of harmful levels of emerging contaminants in the environment.”
In 2020, New York State’s Department of Health had set MCLs at 10 parts per trillion for PFOA and PFOS, and 1 part per billion for 1,4-Dioxane in finished drinking water. Of note, New York was the first state in the nation to develop an MCL for 1,4-Dioxane, and its MCLs were the lowest in the country at the time. The new guidance values, applicable to ambient waters used as drinking water sources, are below the Department of Health’s MCLs “to provide an extra margin of safety against the potential build-up of these contaminants to levels approaching or exceeding the MCLs.”