ASCE has honored the writing team of Charles Schaefer; Dung Nguyen; Emerson Christie; Stefanie Shea; Christopher P. Higgins, Ph.D., A.M.ASCE; and Jennifer Field with the 2022 Samuel Arnold Greeley Award for the paper “Desorption of Poly- and Perfluoroalkyl Substances from Soil Historically Impacted with Aqueous Film-Forming Foam,” Journal of Environmental Engineering, February 2021.

In this selected work, researchers investigated the use of bench-scale experiments to measure and evaluate the desorption rate kinetics of poly- and perfluoroalkyl substances (PFAS) from a vadose zone soil exposed decades ago to aqueous film-forming foams (AFFFs). Kinetic desorption modeling revealed that these observations were likely due to the depletion of shorter-chained PFAS in the rapid equilibrium sorption domain, coupled with their persistence in the kinetically controlled sorption domain. Kinetic modeling also showed that the rate of desorption was proportional to the PFAS aqueous diffusivity, confirming that diffusion limited the rate of release from the soils. Overall, the extent of desorption generally was less than that predicted by published Kocfoc relationships, suggesting that PFAS desorption from field-aged soils may have a less pronounced impact on underlying groundwater than anticipated, particularly for shorter-chained PFAS.

The Samuel Arnold Greeley Award is presented for papers on the design, construction, operation, or financing of water supply pollution control, storm drainage, or refuse disposal projects.