Umeå University's logo

The historical use of firefighting foam has led to the spread of the hazardous group of per- and polyfluoroalkyl substances (PFAS) in the environment. This study examines the distribution patterns and composition of a PFAS contamination originated from firefighting foam, which has migrated from soil to nearby groundwater. The study focuses on a rescue service training site located just outside of Östersund, Sweden. The objective was to map and visualize the pathway of the pollution from the emission source to surface water in a ditch further down the terrain. The methodology included calculations, statistical analyses and visualization through ArcGIS. The result indicates a spread of contamination through groundwater, continuing into surface water. Pollutant concentrations in both surface and groundwater vary seasonally. Frozen ground seems to reduce concentrations, which then increases after the spring thaw. However, the composition of the investigated PFAS substances shows no seasonal variation. Among the PFAS compounds, Perfluorooctane sulfonic acid (PFOS) demonstrated persistence during transport in contrast to 6:2 fluorotelomer sulfonic acid (6:2 FTS), which degraded into other PFAS substances. This study provides deeper insights into how the contamination of PFAS spread from the emission source to the surrounding area, although limitations such as the small number of sampling points and the resultant data can be seen.