Conversations are ramping up around per- and polyfluoroalkyl substances (PFAS), and in an effort to bring those conversations into one room, the Environmental Research & Education Foundation (EREF) is holding its Summit on PFAS in Leachate August 14 and 15 at the Marriott Ypsilanti at Eagle Crest in Ann Arbor, Mich. The summit will bring together practicing engineers, academics, industry professionals, government personnel and policymakers to provide various perspectives and facilitate discussions on PFAS in landfill leachate.
PFAS, a group of man-made compounds manufactured for the last 50 years that are commonly used in industrial processes and consumer products, have become a topic of concern for waste professionals due to the management challenges they present and the significant knowledge gaps associated with the management of these compounds. Conventional treatment processes are ineffective for the removal of PFAS in leachate, and there are a number of analytical challenges when it comes to detecting PFAS in landfill leachate and gas samples.
“Discussions around the topic of PFAS have escalated quickly due to their widespread use in everyday products and media coverage surrounding their possible health and environmental impacts,” says Bryan Staley, president and CEO of EREF. “At this time, there is limited data to guide regulation and management of these compounds. Because of the implications for solid waste management, EREF has focused significant effort to better understand the issue via an educational summit in Michigan and a commitment to funding research related to PFAS to help fill in knowledge gaps.”
At the summit, topics for discussion will include: what are PFAS?; sources and sinks; state agency responses to PFAS; and testing for PFAS. Here’s a sneak peek at some of the presentations that will be showcased at the summit.
PFAS in Landfill Leachate and Municipal Wastewater
Dr. Morton Barlaz of North Carolina State University will present information about a survey he’s conducting in North Carolina that looks at PFAS concentrations in wastewater treatment plants as well as landfill leachate.
The survey, which has been in progress since February 2019, aims to provide a better understanding of whether landfill leachate is a significant contributor of PFAS because it would make it a harder waste stream to control if it is a contributor.
“My job is to analyze the data and evaluate what we can learn from it with respect to the importance of leachate versus wastewater as a source of PFAS to the environment and to write a report that will go to the North Carolina legislature to address those questions for them because they are the ones who have the power to drive appropriate policy,” says Barlaz.
The survey includes information from about 23 wastewater treatment plants and 14 landfills, and Barlaz will share some of that data as well as some insights about the concern of PFAS during his presentation.
How Receiving Facilities are Dealing with PFAS
During a panel discussion moderated by Anne Germain of the National Waste & Recycling Association, Christina Pearse of Republic Services, Sam Nicolai of Casella Waste Systems and Stephen Kuplicki of Great Lakes Water Authority will explain how their facilities are currently managing PFAS.
Right now, Casella sorts waste into different categories and treats sourced materials different than waste streams that have PFAS, according to Nicolai. The company also has made changes at some sites to stop accepting materials directly from PFAS manufacturers and remediation sites that are known to have high concentrations of PFAS.
“As the industry learns more about this class of compounds and its effect on the environment, we’re having to adjust how we deal with these materials, make changes to the types of materials we do and do not accept, decide which kinds of testing we require, etc.,” says Nicolai.
One example is wastewater sludges, which contain a fair amount of compounds, but particular compounds are different than the ones found in leachate so more research needs to be done on whether PFAS compounds are coming out of sludge, staying in the sludge inside a landfill environment or being transformed as they go through the processes, explains Nicolai, who states that Michigan has some good research around this topic, and Vermont is working on a similar research project.
“PFAS is a complicated topic, but we feel it’s timely in terms of getting information out to the industry and then back to manufacturers and consumers because, ultimately, most material containing PFAS is coming from consumer products,” adds Nicolai. “The waste industry is dealing with it at the end of the line, but the solution needs to start at the front of the line with how products are being created.”
Managing PFAS in Leachate
During a panel discussion moderated by Ivan Cooper of CEC, Ryan Thomas of GHD, Pat Stanford of Rochem, Fred Doran of Burns & McDonnell, Dr. Kazem Oskoui of Clark Technology and Steve Mobley of Buckeye Brine will explore how PFAS in leachate is currently managed and how these compounds could be better managed in the future.
Currently, some landfill operators are investing in separation technologies to address PFAS contamination, with the main three being granular activated carbon (GAC), ion exchange (IX) and reverse osmosis (RO). GAC is where PFAS are passed through a GAC vessel and adsorbed into the carbon, and the pretreated leachate passes through. IX is where leachate passes through resins in a vessel that binds PFAS. And RO is where leachate flows through a membrane, leaving the separated PFAS to be collected in a concentrated solution.
“While separation technologies are pretty common, destructive technologies haven’t really progressed yet and are in the early stages of development and research,” says Cooper. “With destruction, you can break carbon-forming bonds, which are some of the strongest in nature, but the concern with breaking apart the bonds is you don’t know what other constituents you may uncover.”
During the panel discussion, Cooper will highlight these technologies as well as a of developing technologies and limited application technologies that are being explored for managing PFAS in leachate. Some of the developing technologies are chemical oxidation, thermal decomposition, solvated electron reduction, electron beam, absorbents, PerfluorAd, nanoporpous nets and boron doped diamond electrode-oxidation. Some of the limited application technologies are electrochemical oxidation, advance oxidation, zero valent iron reduction plus bio treatment, chemical oxidation plus bio treatment, non-thermal plasma, hydrothermal, ScisoR, plasma and deep well injection.
“There has been research done in Michigan, Oklahoma and Australia as well as by a researcher at Rutgers University that has given us a good start, but there is still a lot of research that needs to be done and questions that need to be answered surrounding PFAS in leachate,” says Cooper.
For more information on the summit, click here.