On January 14, the U.S. Environmental Protection Agency (EPA) released the Draft Sewage Sludge Risk Assessment for Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonic Acid (PFOS) for public comment. The draft risk assessment reflects the agency’s latest scientific understanding of the potential risks to human health and the environment posed by the presence of PFOA and PFOS in sewage sludge that is land applied as a soil conditioner or fertilizer (on agricultural, forested, and other lands), surface disposed (e.g., placed in a sewage sludge-only landfill called a monofill), or incinerated. From now until March 17th, the draft risk assessment is available for public comment in the Federal Register.
What is an EPA Risk Assessment?
Risk assessments are an important part of the EPA’s regulatory process and serve as a scientific analysis of the health risks of PFOA and PFOS to people, livestock, or wildlife across the country. The draft risk assessment focuses on those living on or near impacted sites (e.g., farm families and their neighbors) or those that rely primarily on their products (e.g., food crops, animal products, drinking water); the draft risk assessment does not model risks for the general public.
What are the Findings from the Risk Assessment?
The risk assessment’s findings reveal that there may be human health risks exceeding the EPA’s acceptable thresholds for some scenarios when land applying biosolids that contain 1 ppb of PFOA or PFOS. The EPA also finds that there may be human health risks associated with drinking contaminated groundwater sourced near a surface disposal site when sewage sludge containing 1 ppb of PFOA or sewage sludge containing 4 to 5 ppb of PFOS is disposed in an unlined or clay-lined surface disposal unit.
What to Expect Next
After the public comment period has closed, the EPA will consider the comments received, revise the draft risk assessment as appropriate, and prepare a final risk assessment. The final risk assessment will help inform the EPA’s potential future regulatory actions under the Clean Water Act (CWA). If the final risk assessment indicates that there are risks above acceptable thresholds when using or disposing of sewage sludge, the EPA expects to propose a regulation under CWA section 405 to manage PFOA and/or PFOS in sewage sludge to protect public health and the environment.
Resources
The EPA has compiled a list of resources on the main draft risk assessment webpage that help further outline the draft risk assessment and its implications. Relevant documents are:
Fact Sheet: Draft Sewage Sludge Risk Assessment for PFOA and PFOS
Fact Sheet: Draft Sewage Sludge Risk Assessment for PFOA and PFOS: Information for Wastewater Treatment Plants
Frequent Questions and Answers
If you’re interested in discussing best practices, sharing experiences, and gaining exclusive insights on cutting-edge PFAS treatment and destruction technologies with 12+ other leading utilities in the US, contact Patrick Dube for information about Isle’s PFAS Utility Partnership Project.