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Understanding the fate and transport of per- and polyfluoroalkyl substances (PFAS) at contaminated sites is crucial for effective remedial and regulatory decision-making. This interdisciplinary study offers a novel approach for estimating and mapping PFAS sorption properties and their impact on PFAS fate and transport. By integrating electromagnetic induction (EMI) surveys, physical and chemical sediment characterization, mineralogical characterization, and batch sorption experiments of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), we develop a comprehensive mapping of sorption dynamics. Sediments collected from a compound bar deposit were analyzed to establish correlations between EMI signal, sediment characteristics, and PFOA and PFOS sorption distribution coefficients (Kd). Sorption behavior and EMI response of these compounds were consistent with the sediments’ physical and chemical properties where Kd and electrical conductivity was higher with finer grain size, higher organic matter content, and higher aluminum and iron contents. The study demonstrates that EMI effectively maps PFAS sorption properties spatially, providing crucial insights into the sedimentological controls that govern both EMI responses and PFAS sorption. Correlation analysis yielded Pearson correlation values of 0.71 for EMI-PFOA Kd and 0.56 for EMI-PFOS Kd, underscoring the potential of EMI in predicting the spatial distribution of PFAS sorption in complex sedimentary environments. While these Pearson correlation values indicate moderate to strong correlations, their significance is amplified by the cost-effectiveness and extensive aerial coverage of EMI, the sparsity of sediment samples typically collected for batch sorption, and their spatial distribution. These results highlight the potential of EMI to identify sorption hotspots, thereby guiding targeted remediation efforts and enhancing site management strategies, ultimately reducing both costs and environmental impacts.
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This content will become publicly available on December 1, 2025
Sensitivity of mass flux reduction and mass removal of perfluoroalkyl substances to groundwater flow and transport parameter variability and heterogeneity
Heterogeneity of soil hydraulic (e.g., hydraulic conductivity (KS), porosity (θS)) and chemical (e.g., solid-phase adsorption (Kd)) properties complicates contaminant transport by creating spatial variability in sources of contaminant leaching. There is a knowledge gap on the effect of the interplay between these properties on the retardation and transport of per- and polyfluoroalkyl substances (PFAS) with different properties including carbon–fluorine chain-length and functional groups even in water-saturated conditions. Breakthrough curves have been used to evaluate PFAS transport behavior through heterogeneous media, including arrival time, maximum concentration, and tailing behavior. Contaminant mass flux reduction and mass removal correlations are also compared using numerical modeling to characterize PFAS transport through different source zones within a two-domain, heterogeneous system with comparison to homogeneous scenarios under water-saturated conditions. With heterogeneous properties, model sensitivity to KS was the highest among the other parameters and was controlled by the KS ratio between the different soils. The PFAS models in the homogeneous and heterogeneous scenarios were both sensitive to θS, depending on PFAS chain length. However, long-chain PFAS were less sensitive to θS variability compared to short-chain PFAS due to their higher Kd. The homogeneous and heterogeneous scenarios were equally sensitive to Kd variability, which was dependent on PFAS chain length.
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- Award ID(s):
- 2142686
- PAR ID:
- 10566035
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Journal of Hydrology
- Volume:
- 645
- Issue:
- PB
- ISSN:
- 0022-1694
- Page Range / eLocation ID:
- 132268
- Subject(s) / Keyword(s):
- PFAS Heterogeneity Transport Model sensitivity Mass flux reduction Mass removal
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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