Grantee Research Project Results

Fundamentals of Adsorption, Desorption, and Biodegradation of PFAS and Precursor Compounds in the Soil and Landfill Leachate System and An Innovative Treatment Strategy for Their Removal in Landfill Leachate and Groundwater

EPA Grant Number: R839660
Title: Fundamentals of Adsorption, Desorption, and Biodegradation of PFAS and Precursor Compounds in the Soil and Landfill Leachate System and An Innovative Treatment Strategy for Their Removal in Landfill Leachate and Groundwater
Investigators: Xiao, Feng
Institution: University of North Dakota
EPA Project Officer: Hahn, Intaek
Project Period: August 1, 2019 through July 31, 2022 (Extended to July 31, 2023)
Project Amount: $498,907
RFA: Practical Methods to Analyze and Treat Emerging Contaminants (PFAS) in Solid Waste, Landfills, Wastewater/Leachates, Soils, and Groundwater to Protect Human Health and the Environment (2018) RFA Text | Recipients Lists
Research Category: PFAS Treatment , Drinking Water , Water , Human Health , Water Quality

Objective:

Identify the governing soil sorption and desorption mechanisms (thermodynamics and hysteresis) of per- and polyfluoroalkyl substances (PFAS) in landfill leachate.
Investigate the biodegradation of sorbed precursor compounds of perfluoroalkyl acids (PFAAs) and examine the effects of sorption hysteresis.
Innovatively integrate and enhance commonly used water treatment technologies to effectively and practically remove PFAS from the test water.

Approach:

The first and second objectives will be achieved by:

studying the sorption, desorption, and biodegradation of 17 relevant PFAS including EPA listed high-priority PFAAs and their precursor compounds in the soil and leachate system.
determining the hysteresis index of PFAS and the variations of soil properties (e.g., porosity) in relation to the sorption and desorption of PFAS; and
investigating the bioavailability of soil-associated PFAA's precursor compounds and the effects of sorption and desorption on the microbial degradation process.

The role of important leachate and soil quality parameters on the sorption/desorption/biodegradation of PFAS will be established. This proposed research will also develop an innovative strategy that can remove and decompose PFAS of various classes. The third objective will be achieved by evaluating the performance of the proposed treatment system integrated with conventional water treatment processes in different scenarios designed to removal PFAS from landfill leachates or groundwater. Preliminary results show great promise for these strategies.

Expected Results:

The expected outputs include

a database of soil sorption, desorption, and biodegradation of PFAS in landfill leachates;
scientific reports documenting the effects of sorption and sorption hysteresis on the biodegradation of PFAA's precursor compounds;
an innovative strategy to remove and destroy PFAS in aqueous media; and
an innovative treatment system that brings synergies between leachate treatment and PFAS-contaminated groundwater potentially used for drinking water.

The expected outcomes include an increase in the ability to predict the fate of leachate-derived PFAS in the soil environment, and an improved ability to mitigate or minimize the risks of PFAS. The research may also improve the scientific foundation for environmental policy and decision-making related to precursor compounds of PFAAs, and will ultimately mitigate the unwanted on-site generation of PFAAs from precursor compounds.

Publications and Presentations:

Publications have been submitted on this project: View all 15 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 13 journal articles for this project

Supplemental Keywords:

organic contaminants, environmental protection, water purification, high-resolution mass spectrometry, porosimetry

Progress and Final Reports:

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.