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For Release: Wednesday, March 15, 2023

DEC Releases Final Ambient Water Quality Guidance Values for PFOA, PFOS, and 1,4-Dioxane

Guidance Builds on State's Nation-Leading Actions to Protect Public Health and the Environment and Regulate Emerging Contaminants

New York State Department of Environmental Conservation (DEC) Commissioner Basil Seggos today announced the issuance of final water quality guidance values to regulate Perfluorooctanoic acid (PFOA), Perfluorooctanesulfonic acid (PFOS), and 1,4-Dioxane (1,4-D) in New York State waters. The 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. Additionally, the new guidance values for PFOS and 1,4-Dioxane provide protection for aquatic life.

"DEC continues to advance stringent water quality requirements backed by the latest science on emerging contaminants to ensure New Yorkers and our environment are protected," Commissioner Seggos said. "Finalization 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, reinforces the levels adopted by our partners at the State Department of Health for drinking water, and prioritizes the health and wellbeing of our communities and ecosystems."

The guidance values released today provide complementary protection of ambient waters used as drinking water sources. The guidance 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. Certain types of industrial discharges have been assessed as potentially being a more concentrated contaminant source, and these contaminants are best controlled at the industrial sources rather than at downstream treatment systems. In addition to the final guidance implementing actions to control industrial discharges, DEC is actively working on proposing draft guidance to address emerging contaminants discharged through Publicly Owned Treatment Works (POTWs).

DEC released the proposed draft guidance values for public review and comment in October 2021, and conducted a thorough review of comments submitted and the latest information about the effects of emerging contaminants in surface waters. The final guidance values are:

Chemical Final Ambient Water Quality Guidance Values
Human Health Aquatic Life
Chronic Acute
PFOA 6.7 ppt N/A N/A
PFOS 2.7 ppt 160 ppb (fresh)
41 ppb (saline)
710 ppb (fresh)
190 ppb (saline)
1,4-Dioxane 0.35 ppb 18,000 ppb (fresh)
7,000 ppb (saline)
160,000 ppb (fresh)
63,000 ppb (saline)

"Implementation of these guidance values provides vital protection for source waters used by public water systems," said DOH Acting Commissioner Dr. James McDonald. "New York State's public drinking water standards for PFOA, PFOS and 1,4-Dioxane are among the most protective in the nation. Implementation of DEC's guidance values will reduce discharges of these contaminants to the environment, and bolster protections to the water supplying New York's public water systems."

In 2020, New York State set maximum contaminant levels (MCLs) of 10 parts per trillion (10 ppt) each for PFOA and PFOS, and 1 part per billion (1 ppb) for 1,4-dioxane. In 2020, New York was the first state to develop an MCL for 1,4-Dioxane. These drinking water standards were promulgated under the advice and support of the New York State Drinking Water Quality Council, a body of water quality experts and scientists charged with recommending limits for emerging contaminants that have been pervasive in public drinking water systems and to help fill the regulatory gap in the absence of federal standards.

The new Guidance Values are below DOH's MCLs for PFOA, PFOS, and 1,4-Dioxane, to provide an extra margin of safety against the potential build-up of these contaminants to levels approaching or exceeding the MCLs. The proposed Guidance Values were derived by procedures established in Title 6 of the New York Codes, Rules, and Regulations (NYCRR) Part 702. These lower values complement DOH's drinking water MCLs by ensuring permitted industrial discharges do not cause their exceedance. In addition, the U.S. Environmental Protection Agency recently proposed national drinking water standards for PFOA and PFOS, and additional actions to limit exposure to PFNA, GenX, PFHxS, and PFBS. These proposals will be released for public comment soon. For additional info, visit EPA's website (leaves DEC website).

The guidance is described in Technical and Operational Guidance Series (TOGS). The full text of the TOGS documents and additional supporting information are available on the DEC website or by contacting by mail: New York State Department of Environmental Conservation, 625 Broadway, Albany NY 12233-3500, ATTN: Michelle Tompkins; by phone by calling (518) 402-8233; or by email to

New York State continues to lead the nation in responding to emerging contaminants like PFAS and holding polluters accountable for cleaning up chemicals from our environment. Governor Hochul's 2023 State of the State proposed establishing a new program to offer financial assistance to municipalities to investigate sources of contamination and remediate contaminated sites over the next five years. New York also continues to increase its investments in clean water infrastructure to reduce the impact of contaminants like PFOA, PFOS, and 1,4-dioxane on the State's water resources. Most recently, in the 2023 State of the State agenda, Governor Hochul committed to invest an additional $500 million in clean water funding in her upcoming budget, bringing New York's total clean water infrastructure investment to $5 billion. To leverage these investments and ensure ongoing coordination with local governments, Community Assistance Teams will provide proactive outreach to small, rural, and disadvantaged communities to help them access financial assistance to address their clean water infrastructure needs.

DEC also recently announced several new laws starting this year that will help protect public health and the environment by reducing exposure to emerging contaminants in everyday items that could find their way into waterbodies when disposed. Laws were implemented that will cover 1,4-dioxane, PFAS, and other chemicals used in household cleaning, personal care, cosmetics, food packaging, and children's products.

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