Wastewater and Biosolids (PFAS)

Wastewater and biosolids are critical pathways for PFAS entering the environment. Conventional wastewater treatment plants (WWTPs) do not remove or destroy PFAS—they pass through treatment processes and are discharged in effluent or concentrated in biosolids (sewage sludge). When biosolids are applied to agricultural land as fertilizer, PFAS can contaminate soil and groundwater. EPA is developing regulatory approaches for PFAS in biosolids under the Clean Water Act and has completed draft risk assessments for PFOA and PFOS in biosolids.

EPA PFAS Strategic Roadmap; Clean Water Act §405; EPA Draft Biosolids Risk Assessment for PFOA/PFOS; EPA 2026 Multi-Sector General Permit (proposed PFAS monitoring).

Wastewater discharge is an emerging liability vector for PFAS. Companies that discharge PFAS-containing wastewater—directly or to publicly owned treatment works (POTWs)—may face new permit requirements, pretreatment standards, and liability for downstream contamination. EPA’s proposed 2026 Multi-Sector General Permit includes PFAS monitoring requirements for certain industrial sectors. Companies should audit their wastewater discharge for PFAS content and implement source reduction measures.

A textile finishing operation discharges process water containing fluorotelomer-based PFAS to the local municipal wastewater system. The POTW cannot remove these PFAS, which pass through to the river. Downstream, a drinking water utility detects PFAS above MCL thresholds and traces the contamination upstream. The textile facility faces potential pretreatment requirements, cost recovery claims, and state enforcement action.