a. Innovativeness of the proposed technology Forever Analytical Services (FAS) has developed particle-induced gamma-ray emissions (PIGE) spectroscopy for the high-throughput screening of per- and poly-fluoroalkyl substances (PFAS) in water. This proposal seeks to extend the utility of this technique to the field by developing a field-deployable solid phase extraction (SPE) device containing a filter. Filters are then placed in an accelerated beam of protons where the resulting gamma-rays are measured to determine total fluorine content. PIGE is the only spectroscopic method for total fluorine analysis, which is rapid, quantitative, and sensitive. b. Technical feasibility compared to current technologies Rinsing a SPE filter with methanol and performing a second rapid PIGE measurement will distinguish inorganic fluoride from organofluorine. Limit of detection (LOD) is volume dependent, and since the SPE is performed in the field, larger sampling volumes can be used to lower the LOD below that of other existing total organic fluorine quantification methods such as combustion ion chromatography (CIC). Filters can be eluted to provide species information for select samples of interest. To date the FAS SPE/PIGE process has been demonstrated in the laboratory under controlled conditions. c. Commercial potential (applications and end users) This field-deployable SPE/PIGE method will provide regulatory agencies, PFAS-impacted communities, and environmental end-users with a fast and reliable method for screening for the presence of PFAS prior to speciation. This technique does not attempt to replace existing EPA methodologies, but rather to provide additional total organic fluorine screening information that is collected on-site in known areas of contamination for improved decision making. Given the widespread environmental contamination of our waters with PFAS, we anticipate that any tool that can screen samples more quickly and allow an end-user to select where to analyze in detail for specific PFAS will provide significant long-term cost savings. d. Potential for environmental feedback The SPE device paired with PIGE will allow on-site sampling for PFAS characterization more quickly and allow better-guided decision making for environmental remediation efforts. This technology will screen out samples that do not have significant PFAS and save money spent on the unnecessary analysis of clean water samples. Lastly, this device will provide environmental agencies information about the presence of all PFAS, not just regulated species. This is of increasing environmental interest and a precautionary approach to take, when coupled with the development of SPE methods proposed here to select the PFAS of most concern.