Navigating the future of biosolids and PFAS: Regulatory shifts and industry adaptation

Over the past several years, per- and polyfluoroalkyl substances (PFAS) have moved from an emerging concern to a defining challenge for wastewater utilities. Since our 2024 examination of PFAS and biosolids, the regulatory environment has continued to evolve, often faster at the state level than federally, forcing utilities to navigate a patchwork of regulatory frameworks. What is emerging, however, is greater variability in state responses, ranging from outright bans to more targeted, pragmatic frameworks aimed at managing exposure while preserving beneficial use.

Federal momentum remains slow, but consequential

At the federal level, progress on PFAS regulation in biosolids remains deliberate. In 2024, the EPA made PFAS a clear priority through its PFAS Strategic Roadmap, which emphasizes source reduction, research and remediation. One roadmap activity that drew particular interest from biosolids managers was the draft risk assessment for PFOA and PFOS in land-applied biosolids, released by EPA in January 2025.

Importantly, the draft risk assessment itself does not establish enforceable standards, and EPA noted that it does not speak to risks to the general population. Instead, it may represent a foundational step that could shape future federal action. In the absence of numeric federal limits, states have continued to move forward independently, often explicitly stating they are unwilling to wait for EPA action.

EPA's designation of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) as hazardous substances under CERCLA has introduced new uncertainty for land application of biosolids. While EPA has indicated that wastewater utilities are not an enforcement focus, concerns about third-party litigation and long-term liability remain. Although existing CERCLA provisions include limitations intended to reduce potential liability for land application activities, questions remain regarding long-term exposure and third-party litigation. Both EPA and the biosolids community have pointed to the need for additional clarity from Congress, including legislative protections for water and wastewater systems. Utilities emphasize that they function as passive receivers of PFAS and were not designed to remove these compounds before they concentrate in biosolids, underscoring the importance of regulatory approaches that reflect the role of wastewater systems within the broader PFAS lifecycle.

States take the lead: Bans versus tiered approaches

With limited federal direction, state legislatures and regulators have become the primary drivers of PFAS policy for biosolids. Early legislative responses often centered on outright bans on land application. While politically attractive to some, these bans have had unintended consequences and have proven to be very costly for utilities.

Bans can abruptly eliminate the dominant outlet for wastewater solids, beneficial reuse through land application, forcing utilities toward landfilling or incineration, both of which carry higher costs, limited capacity and their own environmental tradeoffs. As the unintended consequences become clearer, some are following the early lead set by Michigan and adopting tiered, concentration-based frameworks.

The tiered model gains traction

Michigan was the first to implement the tiered approach, which is increasingly being adopted elsewhere. It establishes PFAS concentration thresholds that trigger graduated responses rather than automatic bans. Under a typical framework:

• Biosolids below a lower threshold (e.g., PFOS or PFOA below 20 µg/kg) may continue to be land applied without additional action;
• Intermediate concentrations prompt investigation, enhanced monitoring and source control efforts, particularly targeting industrial contributors;
• High concentrations may restrict or halt land application until PFAS levels are reduced.

This approach has gained favor with regulators because it is targeted and aligns with the EPA as well as a general focus on source reduction as a control. It also recognizes a critical reality: wastewater treatment facilities and landfills are PFAS receivers, not primary sources.

Recent legislative activity underscores this shift. In Virginia, a proposed ban was amended to a tiered framework following engagement among utilities, regulators and lawmakers. Even in states that previously enacted strict controls, regulators have acknowledged the need to reassess policies as implementation challenges become clearer.

While bans have not disappeared entirely, and may reemerge in future legislative sessions, the overall trajectory points toward tiered regulation as a preferred model among states actively addressing PFAS in biosolids.

Why pragmatism is prevailing

Several factors are driving this regulatory recalibration.

First, the environmental and economic value of biosolids beneficial use is increasingly difficult to ignore. Land-applied biosolids recycle nutrients, improve soil health, increase drought resilience and reduce reliance on energy-intensive commercial fertilizers. At a time of volatile fertilizer prices and growing attention to climate impacts, these benefits carry renewed weight.

Second, bans do little to reduce PFAS loading at its source. PFAS enter wastewater systems from a wide array of industrial and consumer products, meaning that eliminating land application does not eliminate PFAS, it merely shifts it to other locations such as landfills.

Third, utilities and regulators alike are recognizing that abrupt bans can undermine long-term solids management resilience. Landfills are increasingly restricting acceptance of high-moisture wastes, while new incineration capacity faces steep capital costs and public opposition. Tiered approaches, by contrast, preserve optionality while allowing time for data collection, source control and technology evaluation.

Technology and operational responses evolve

In parallel with regulatory shifts, the industry's approach to managing PFAS in biosolids has matured. Earlier conversations focused heavily on emerging destruction technologies such as pyrolysis, gasification and supercritical water oxidation. These technologies show promise, though long-term reliability and operational needs continue to be assessed. Their products, such as biochar, have potential for beneficial reuse in emerging markets such as concrete additives.

More recent efforts have emphasized practical, near-term measures that utilities can deploy using existing infrastructure. Source control programs targeting industrial dischargers remain one of the most effective tools for reducing PFAS concentrations entering treatment plants. Similarly, focusing treatment on smaller, more concentrated streams, such as filtrate or recycle flows, may achieve meaningful reductions without treating entire plant flows.

Operational practices such as biosolids drying have also gained attention. While drying does not destroy PFAS, it can reduce measured concentrations and significantly lower volumes requiring management, helping utilities remain below regulatory thresholds while preserving reuse opportunities.

Together, these strategies reflect a broader industry shift away from crisis-driven responses and toward integrated PFAS management embedded within existing solids programs.

Education as a regulatory tool

One consistent lesson from recent legislative cycles is the importance of education. Policymakers often encounter PFAS through alarming headlines rather than technical context, leading to well-intentioned but impractical proposals. Utilities and industry associations have increasingly invested in legislator briefings, facility tours and fact-based guidance to explain how biosolids are managed, where PFAS originate, and what different regulatory choices mean in practice. These efforts are paying dividends. In multiple states, lawmakers have revised or withdrawn proposed bans after gaining a clearer understanding of their impacts. While future legislative battles are inevitable, the groundwork for more informed decision-making is being laid.

Looking ahead

The regulatory landscape for PFAS in biosolids remains dynamic, with continued uncertainty at the federal level and active experimentation among states. What is clear, however, is that momentum is building around tiered, risk-based approaches that balance environmental protection with operational feasibility.

For utilities, the path forward lies not in waiting for a single regulatory answer, but in building flexible, data-driven programs that combine source control, targeted treatment and proactive engagement with regulators and legislators. As PFAS policy continues to evolve, pragmatism —not prohibition — is increasingly shaping the future of biosolids management.