|Per-and Polyfluoroalkyl Substances (PFAS) have emerged as a concern at many sites as they are persistent, bioaccumulative, and have demonstrated toxicity in laboratory animals, therefore it is a critical need to understand their migration pathways and bioavailability for proper delineation and risk characterization. Although there are established grab sampling techniques available for PFAS, these capture the total concentration which may result in an overestimation of risk to human and ecological receptors. Passive sampling in sediment porewater and surface water is an accepted approach to assess bioavailability and risk through the dissolved phase of many known contaminants (i.e., PCBs, PAHs, pesticides, metals etc.). Given their partially water-soluble nature, a diffusion-based passive sampler is a good candidate for quantification of dissolved PFAS. This presentation will highlight both targeted and non-targeted results from in situ field testing of a novel passive sampler, SPFASsive, and compare these results with those obtained from traditional grab sampling.