As of mid-June 2025, agricultural stakeholders are increasingly aware of claims by clean water advocates and regulatory concerns that land-applying municipal sewage waste (biosolids) may contaminate soil and groundwater with per- and polyfluoroalkyl substances (PFAS). In 2023, approximately 60% of U.S. biosolids were land-applied, according to the U.S. Environmental Protection Agency (EPA). Also, according to the EPA, PFAS exposure may pose health risks, though ongoing research continues to assess the impacts of low-level, long-term exposure, especially in children.
Federal and state regulators are working to eliminate PFAS compounds considered the most dangerous to our environment and our health, perfluorooctanoic acid (PFOA) or perfluorooctane sulfonic acid (PFOS), from consumer products. However, reducing environmental PFAS loads will also require alterations to current practices which may simply be recycling existing environmental loads, including agricultural uses of biosolids. Legal changes are expected. Farmers, who own or rent most of the land involved in applications of biosolids, will be a central focus.
What we have seen over the last few years has been a smattering of individual state government actions restricting and limiting the practice of land application of biosolids in various ways. In some extreme instances, these have included quarantine orders of entire tracts of farmland preventing or limiting further agricultural production.
A compilation of those individual state actions has been assembled by a national environmental consulting firm, ALL4 , and it is publicly available at this link: State-by-State Regulatory Update (March 2025 Revision)(see Table 2 – State Water Regulation Highlights). This documents the patchwork in regulatory landscape faced across the country.
Complicating enforcement, biosolids are increasingly transported across state lines, undermining the consistency of state-level regulation and calling for a more unified approach. This regulatory inconsistency challenges both land-applicators and regulators tracking PFAS from production to final disposal.
While the Clean Water Act (CWA), via the National Pollutant Discharge Elimination System (NPDES), governs the permitting of biosolid land applications, PFAS-specific regulation under this system remains limited. EPA has issued only non-binding guidance to states for performing their CWA duties.
Adding a new pollutant to those already identified and regulated in biosolids is ultimately controlled by the text of 33 U.S.C. §1345(d) of the CWA (“Disposal or Use of Sewage Sludge”), and regulations at 40 CFR Part 503. These require EPA to establish numeric limits and mandatory management practices to protect public health and the environment from the reasonably anticipated adverse effects of designated pollutants during the use or disposal of biosolids. EPA is also required to review these regulations at least every two years and develop standards where evidence warrants. To date, EPA has not established numeric PFAS limits for biosolids, but a draft risk assessment released on January 15, 2025, marks a first step in that direction.
Historically, EPA’s “PFAS Strategic Roadmap” progress reports have stated it would complete by winter 2024 a risk assessment for PFAS in biosolids for use in determining whether to regulate these particular substances in biosolids.
On January 15, 2025, EPA commenced that process by publishing in the Federal Register the following document, “Draft Sewage Sludge Risk Assessment for Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonic Acid (PFOS). After multiple extensions, the public comment period is now scheduled to close on August 14, 2025. The public comments so far are available at the following regulatory docket: EPA-HQ-OW-2024-0504.
The upshot of EPA’s draft risk assessment states the following:
The draft risk assessment indicates that there are potential risks to human health to those living on or near impacted properties or primarily relying on their products from land application. . .
* * *
After the public comment period has closed, the EPA will. . . prepare a final risk assessment. . . 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.
Last year, on June 6, 2024, a federal lawsuit was commenced seeking to compel EPA to establish regulatory standards for PFAS in land-applied biosolids. Farmer, et al. v. EPA, No. 24-cv-1654. The plaintiffs in that case allege the EPA’s inaction has allowed PFAS-laden biosolids to contaminate millions of acres, harming farmers and the public. This lawsuit is currently moving slowly with preliminary matters and no resolution is expected for at least another year.
One thing is certain in the coming months and years. Those farmers and agricultural stakeholders across the country involved in the common practice of land-applying biosolids will see significant change mandated in their practices and operations by the emergence of PFAS regulation in biosolids.
Duer, Brook, and Paul Goeringer. “Why aren’t PFAS compounds in land applied biosolids prohibited by EPA?” Southern Ag Today 5(26.5). June 27, 2025. Permalink
