Investigating fate and transport of PFAS' mixtures in the vadose zone at contaminated site

Perfluoroalkyl and polyfluoroalkyl substance (PFAS) are emerging contaminants that have been increasingly reported for adverse effects on ecological systems and human health (Melzer, D., et al., 2010). It is mainly released from fire training sites with the application of aqueous film forming (AFFF), industrial sites, landfills, and wastewater treatment plants/biosolids. Among them, the usage of AFFF during fire-related emergencies and fire-training activities have caused contamination in groundwater, soil and surface water, in particular, there are concerns on the groundwater impact. The vadose zone contamination could be a potential source of long-term PFAS influx to the groundwater. Thus, it is critical to attain improved insight into the fundamental fate and transport processes that control PFAS fate and transport as it migrates from surface soil to groundwater (Andrea K. W., et al., 2017). This problem is exacerbated when sites are contaminated with complex mixtures such as the fluorinated-organic compounds present in AFFF. The failure to fully understand the fate and transport mechanism in the subsurface has implications on the development of remedial solutions to address all forms of contamination present. In this study, we investigated the depthwisedistribution of PFAS compounds in one particular site and provided insights on their fate and transport. (author)