Ask an Expert: What you need to know about PFAS in leachate

In this month’s feature, BC subject matter expert Kevin Torrens talks about PFAS in leachate.

Question: I am an operator of a landfill. It seems like per- and polyfuoroalkyl substances (PFAS) are a hot topic among industry members and regulators. Why am I hearing so much about it and what do I need to consider?

Answer: The solid waste industry is faced with diverse and complex wastewater treatment issues. More stringent discharge requirements and changing regulations place increasing demands on facilities whose core business is not wastewater treatment. Leachate has been a specific area of concern given the general presence of PFAS compounds in most, if not all, leachates that have been analyzed. While landfills are not direct sources of PFAS, it is present in leachate due to its common presence in consumer products and many industrial wastes as well as publicly owned treatment works (POTW) biosolids and sludge.

Complex and complicated

Much of the PFAS research and work being done now is around groundwater and drinking water, which is a comparatively straightforward process (compared to leachate) and is not significantly impacted from other contaminants given their relatively clean nature. PFAS in leachate has proven to be a more complicated issue to tackle due to its complex matrix and high concentrations of other contaminants. BC is working with clients, regulators, and research foundations to raise awareness of leachate’s PFAS challenges and to identify treatment solutions that are suitable and effective for leachate.

Treatability Testing Laboratory

BC has a sophisticated Treatability Testing Laboratory enabling expedited data development to support solution implementation to keep pace with regulatory requirements and public concerns. BC’s Lab provides rapid analyses for treatment approaches proven with leachate for PFAS, such as granular activated carbon (GAC), ion exchange (IX), foam fractionation and reverse osmosis (RO) and their appropriate pretreatment steps. We are also making strategic investments in research and development of destructive and sequestration treatment technologies such as electrochemical oxidation, plasma, super critical water oxidation (SWCO) and solidification to support our clients’ needs for addressing long-term management of PFAS.

Nondestructive treatment technologies such as RO, GAC, and IX resins focus on PFAS removal by separation, which produces residuals that must be managed. This creates potential for long-term risk management costs for PFAS associated liabilities. Conversely, destructive technologies for PFAS are focused on breaking down these chemicals into less harmful end products. The destruction of PFAS in residuals is an area of ongoing research and development. While there are several innovative, destructive technologies under consideration, BC is actively testing technologies which have already been shown to effectively degrade PFAS compounds under laboratory conditions.

Through our Treatability Testing Laboratory, we are able to provide our clients with the full spectrum of services from initial proof-of-concept and bench-testing of technologies through pilot-testing and full-scale design, construction and start-up.

Connection and collaboration

We are also working to make the connection between landfills and publicly owned treatment works (POTWs), which have much in common as “end of the line” managers of consumer wastes. In many cases, landfills and POTWs are dependent on each other for disposal needs. This dependency provides an opportunity for collaboration and discussion of mass-based limits for PFAS that are allocated based on technology and cost considerations. BC has jointly developed local industrial pretreatment limits with POTWs and state regulatory agencies.

Given the current regulatory climate and public concern, it is likely that PFAS will continue to dominate conversations, especially in the solid waste industry. We look forward to continuing to being part of the conversations and solutions.