Few field methods are available for characterizing source zones impacted with aqueous film forming foam (AFFF). Non-invasive geophysical characterization of AFFF source zone contamination in situ could assist with the delineation and characterization of these sites, allowing for more informed sampling regimes aimed at quantifying subsurface poly- and perfluoroalkyl substances (PFAS) contamination. We present initial results from the investigation of the sensitivity of two existing surface and borehole-deployable geophysical technologies, spectral induced polarization (SIP), and low field nuclear magnetic resonance (NMR), to soils impacted with AFFF. To investigate the sensitivity of these methods to AFFF-impacted soil, bench-scale column experiments were conducted on samples consisting of natural and synthetic soils and groundwater. While our findings do not show strong evidence of NMR sensitivity to soil PFAS contamination, we do find evidence that SIP has sufficient sensitivity to detect sorption of AFFF constituents (including PFAS) to soils. This finding is based on evidence that AFFF constituents associated with the pore surface produce a measurable polarization response in both freshly impacted synthetic soils and in soils historically impacted with AFFF. Our findings encourage further exploration of the SIP method as a technology for characterizing contaminant concentrations across AFFF source zones.

很少有现场方法可用于表征受水成膜泡沫 (AFFF) 影响的源区。对水成膜泡沫源区污染进行原位非侵入性地球物理表征有助于这些地点的描绘和表征，从而实现旨在量化地下多氟烷基物质和全氟烷基物质 (PFAS) 污染的更明智的采样制度。我们介绍了两种现有的表面和钻孔可部署地球物理技术（光谱诱发极化(SIP) 和低场核磁共振 (NMR)）对水成膜影响土壤的敏感性调查的初步结果。为了研究这些方法对 AFFF 影响的土壤的敏感性，对由天然和合成土壤以及地下水组成的样品进行了小型柱实验。虽然我们的研究结果没有显示 NMR 对土壤 PFAS 污染的敏感性的有力证据，但我们确实发现了证据表明 SIP 具有足够的敏感性来检测 AFFF 成分（包括 PFAS）对土壤的吸附。这一发现基于以下证据：与孔隙表面相关的水成膜泡沫成分在新受影响的合成土壤和历史上受水成膜泡沫影响的土壤中产生可测量的极化响应。我们的研究结果鼓励进一步探索 SIP 方法作为表征 AFFF 源区污染物浓度的技术。