PFAS · Biosolids and PFAS: Planning Ahead
Why Is PFAS a Concern in Biosolids?
Sewage sludge contains the solids separated during wastewater treatment. Biosolids are treated sewage sludge intended for beneficial use under applicable requirements. PFAS entering the plant can remain in water or associate with solids and appear in biosolids.
Not every biosolids product has the same PFAS profile. Sources, treatment, blending, storage, solids content, and sampling approach differ. A result should identify whether it represents liquid biosolids, dewatered cake, stored material, compost feed, or another point.
EPA released its PFOA/PFOS sewage-sludge risk assessment as a draft in January 2025. In its June 2026 draft biosolids guidance, EPA said that assessment had serious flaws and should not be treated as a final risk finding. The separate 2026 guidance is also a draft. State requirements can be more specific. Do not describe a screening value or draft scenario as a universal federal limit.
Key point: Biosolids decisions require current jurisdiction-specific requirements and representative product data.
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PFAS in Wastewater: Sources, Sampling, Source Control, and Residuals
This page comes from the course. It covers PFAS sources in the sewershed, how PFAS moves through a treatment plant, sampling and lab methods, source control, treatment residuals and biosolids, one step at a time, with short knowledge checks and a certificate of completion.
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