Per- and polyfluoroalkyl substances (PFAS) can move through wastewater, biosolids, landfill leachate, and other residual streams. As regulatory requirements evolve, organizations need to understand these pathways and how they affect treatment, disposal, and land application decisions.

PFAS are being identified across wastewater systems, solid waste facilities, and biosolids management programs.

Wastewater treatment plants, landfills, and biosolids programs are generally not the original sources of PFAS. Instead, they can function as collection and redistribution points for PFAS originating from industrial processes, commercial activities, consumer products, and legacy materials. Understanding these interconnected pathways is critical to identifying sources, designing effective sampling programs, evaluating treatment and disposal alternatives, and anticipating potential regulatory obligations.

How PFAS Move Through Wastewater & Waste Streams

How PFAS Enter Wastewater & Residuals

PFAS enter wastewater systems through multiple pathways. Industrial discharges, landfill leachate, stormwater runoff, and domestic wastewater all contribute to PFAS loading at treatment facilities. Once PFAS reach a wastewater treatment plant, conventional treatment processes are generally not designed to destroy them.

Instead, PFAS are often partitioned between treated effluent and solid residuals. Some compounds remain dissolved in effluent discharged to surface waters, while others accumulate in sewage sludge that is later processed into biosolids. This redistribution creates downstream management challenges.

Because wastewater treatment facilities are not typically equipped with PFAS destruction technologies, they must manage PFAS within existing operations.

PFAS Pathways Through Solid Waste & Landfills

PFAS-containing consumer products, industrial materials, treatment residuals, and contaminated soils disposed of in landfills may contribute PFAS to landfill leachate. When that leachate is sent to a wastewater treatment facility, PFAS can enter another management system and subsequently partition into treated effluent or biosolids. This creates an interconnected pathway in which PFAS may move from products and industrial materials to landfills, from landfill leachate to wastewater treatment facilities, and ultimately into effluent or residual solids.

Understanding that pathway can help landfill operators and wastewater utilities determine where sampling provides the most useful information and whether waste streams or sources are disproportionately contributing to PFAS loading. Coordination between solid waste operators and wastewater utilities is therefore important when developing sampling programs, evaluating treatment options, and communicating with regulators.

Landfill operators must evaluate potential long-term management strategies and associated costs.

PFAS in Biosolids & Land Application Decisions

Biosolids management is a critical area of focus in PFAS risk management. When biosolids are land-applied for agricultural or soil amendment purposes, PFAS may be introduced into soils, where their mobility and potential transport depend on site-specific conditions, compound characteristics, and environmental factors.

Federal and state actions illustrate how PFAS concentrations may influence biosolids management decisions. In January 2025, the US Environmental Protection Agency (EPA) released its Draft Sewage Sludge Risk Assessment for PFOA and PFOS, evaluating potential human health and environmental risks associated with these compounds in sewage sludge that is land applied, surface disposed, or incinerated.

States are also developing their own management approaches. Michigan, for example, requires PFAS monitoring for facilities that land apply biosolids and uses PFOA and PFOS concentrations to determine additional management requirements. Under Michigan's current interim strategy, biosolids containing 100 µg/kg or more of either PFOA or PFOS are considered industrially impacted and cannot be land applied. Concentrations from 20 to less than 100 µg/kg trigger additional requirements, including reduced land application rates, effluent sampling, and source-reduction activities.

For wastewater utilities, these requirements create practical management questions:

Answering these questions increasingly requires utilities to evaluate PFAS concentrations alongside source information, site conditions, applicable regulatory requirements, disposal alternatives, and long-term costs rather than treating biosolids management as an isolated end-of-pipe decision.

Managing PFAS Impacts on Wastewater Treatment Operations

PFAS in wastewater affect operational planning and compliance strategies. New drinking water standards and surface water discharge limits may indirectly increase scrutiny on upstream wastewater contributors. Utilities may face requirements to monitor influent, effluent, and biosolids for specific PFAS compounds.

Industrial pretreatment programs are also evolving. Wastewater utilities are reviewing discharge permits and engaging with industrial users to identify potential PFAS sources and opportunities for source reduction, helping mitigate long-term treatment and disposal challenges.

In some cases, utilities are evaluating advanced treatment technologies such as granular activated carbon (GAC), ion exchange systems, or membrane filtration to address PFAS in effluent. These technologies may reduce PFAS in effluent while concentrating the compounds in spent media, regenerant solutions, membrane concentrates, or other secondary residuals that require treatment or disposal.

Technology evaluations should therefore consider the full PFAS lifecycle, including removal effectiveness for target compounds, influent water chemistry, residual generation and management, disposal pathways, regulatory requirements, and life-cycle costs. A treatment option that effectively reduces PFAS in effluent may still create downstream management challenges if residual waste streams are not incorporated into the treatment strategy.

Preparing PFAS Waste Management Programs for Evolving Requirements

The regulatory landscape surrounding PFAS in waste streams and biosolids continues to evolve across federal and state jurisdictions. Organizations can reduce uncertainty by building the data and decision framework needed to respond as requirements develop.

How APTIM Supports PFAS Waste Stream Management

APTIM supports utilities, municipalities, solid waste operators, and industrial clients across the PFAS waste-management lifecycle. Our teams help clients design and implement sampling programs, interpret PFAS data, identify potential sources, evaluate treatment and residuals-management alternatives, assess risk, navigate evolving regulatory requirements, and develop long-term management strategies.

APTIM brings together technical, regulatory, risk assessment, and waste-management expertise to help clients understand how PFAS move across wastewater, biosolids, landfill leachate, and treatment residuals. This cross-media perspective helps clients evaluate tradeoffs, avoid shifting PFAS risk from one waste stream to another, and make defensible treatment, disposal, and management decisions based on operational needs, regulatory requirements, and long-term costs.

If your organization is evaluating PFAS in wastewater, biosolids, or landfill leachate, APTIM's Remediation & Technical Solutions team can help turn PFAS data into a practical management strategy by identifying sources, comparing treatment and disposal options, and establishing a path forward that accounts for both current requirements and long-term waste-management implications.

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Published September 2026

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