Abstract
Landfill leachate is typically managed to control impacts from certain physical-chemical parameters, such as organic matter, inorganic salts, organic trace pollutants, and heavy metals. Along with these traditional pollutants, per-and polyfluoroalkyl substances (PFAS) are gaining attention for management in landfills, given the high levels observed in landfill leachates. The frequent applications of PFAS in industrial and consumer products and the subsequent management and disposal of PFAS-containing waste have resulted in the emission of these chemicals into the environment, threatening the health of wildlife and humans. This dissertation aimed to evaluate the relationship between PFAS and physical-chemical parameters in multiple types of landfill leachate and within full-scale leachate treatment systems. The first study evaluated whether changes in leachate's physical-chemical parameters at on-site treatment systems (including bulk measurements, oxygen demanding components, and metals) were associated with concentration changes in PFAS. The second study evaluated relationships between physical-chemical properties (bulk measurements, oxygen demand components, and metals) and PFAS concentrations in different types of aqueous landfill samples. The third study first compared the aqueous liquid PFAS and physical-chemical characteristics collected in different landfills. Then within a landfill type, variability and correlation were further assessed by evaluating PFAS and physical-chemical characteristics in landfill aqueous samples. The evaluation of correlations and comparisons with PFAS and physical-chemical parameters in these three studies could help establish ranges for PFAS releases from landfills and serve as a starting point to assess the potential mechanisms that influence levels of PFAS and physical-chemical parameters in different landfill aqueous samples.