Concerns over PFAS in biosolids have been growing, particularly in the wake of Maine’s 2022 ban on land application. The recent U.S. EPA Draft PFAS Sewage Sludge Risk Assessment has only intensified these discussions, raising questions about the long-term viability of beneficial reuse programs for biosolids. Carollo’s Rashi Gupta, national wastewater practice director, and Kyle Thompson, national PFAS lead, spoke with Treatment Plant Operator about the implications of this risk assessment and the steps utilities should take to prepare for potential regulatory changes.
What the EPA’s PFAS Risk Assessment Means for Utilities
The EPA’s assessment focused specifically on PFOA and PFOS—two of the most widely studied PFAS compounds. The agency analyzed 18 different exposure pathways related to land-applied biosolids, including how these chemicals could transfer from soil to groundwater, crops, livestock, and ultimately, human consumption.
“The EPA’s assessment has potential to reshape how utilities approach biosolids management. Understanding these changes early will be crucial if utilities are to develop cost-effective, sustainable solutions,” Rashi emphasizes.
The Challenge of Managing PFAS in Biosolids
While the EPA’s risk assessment does not address general public exposure, it models risks for a hypothetical farm family living on land where biosolids are applied. This conservative approach has raised concerns about how the findings will influence public opinion, regulatory decisions, and biosolids management options.
Rashi warns that the perception of risk alone could have far-reaching consequences. “Farmers who have a perception that the biosolids are unsafe would not want them to be land-applied. And landfills may also say they don’t want the material because it will lead to PFAS in their leachate, for which they fear they could be held liable.”
The situation in Maine provides a case study of what can happen when land application is no longer an option. After the ban, utilities struggled to find disposal outlets, leading to stockpiling and increased reliance on the state’s limited landfill capacity. “This shows why it’s important to know the consequences of imposing restrictions and the potential end results,” Rashi notes.
Strategies for Utilities Facing PFAS Regulations
As regulatory uncertainty looms, utilities must proactively assess their biosolids management strategies. Carollo recommends starting with a data-driven approach. “We suggest they look at their data to understand where they are now,” says Rashi. Identifying industrial PFAS sources in a watershed or sewershed can help utilities implement source control measures, which have proven effective in reducing PFAS concentrations in biosolids.
Beyond source control, utilities should also evaluate emerging PFAS treatment technologies. While promising, these technologies still present challenges related to cost, scalability, and the fate of PFAS in solid, liquid, and gaseous byproducts. Kyle suggests that utilities conduct pilot testing when possible, as this will help both individual agencies and the broader industry better understand viable solutions.
Preparing for an Uncertain Regulatory Future
While the EPA has not yet outlined a definitive timeline for implementing new regulations, a public comment period is underway. After this phase, the agency will review feedback and consider risk management options, including the feasibility and costs of alternative biosolids disposal methods.
Given the potential for regulation, Carollo emphasizes that utilities must act now to prepare for future changes. “They should be strategically planning so that if a regulation comes down the pike and requires the destruction of PFAS, they know what their options are and how to get set up to exercise them,” Kyle explains. “That’s not going to be easy. It takes a considerable amount of time and money to get those potential options online.”
To learn more about Carollo’s insights on this evolving issue, read the full Treatment Plant Operator article.