Geospatial and socioeconomic factors of PFAS contamination in private drinking water wells: Insights for monitoring and management

Authors: KOSIARSKI, KELLY - Pennsylvania State University; Veith, Tameria; KIBUYE, FAITH - Pennsylvania State University; FETTER, JENNIFER - Pennsylvania State University; BOSER, SUSAN - Pennsylvania State University; VANDEN HEUVEL, JOHN - Pennsylvania State University; THOMPSON, CHERYL - Pennsylvania State University; PREISENDANZ, HEATHER - Pennsylvania State University

Submitted to: Journal of Environmental Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/16/2025
Publication Date: 5/27/2025
Citation: Kosiarski, K., Veith, T.L., Kibuye, F., Fetter, J., Boser, S., Vanden Heuvel, J.P., Thompson, C., Preisendanz, H. 2025. Geospatial and socioeconomic factors of PFAS contamination in private drinking water wells: Insights for monitoring and management. Journal of Environmental Management. 388. Article 125863. https://doi.org/10.1016/j.jenvman.2025.125863.
DOI: https://doi.org/10.1016/j.jenvman.2025.125863

Interpretive Summary: Chemicals known as per- and polyfluoroalkyl substances (PFAS) have been used historically in manufactured items but have been found to not break down naturally in the environment and to not be filtered out of the groundwater by the soil profile. The widespread presence of these chemicals in groundwater increases the potential for uptake of PFAS in private drinking wells. Drinking water containing PFAS, even at very low concentrations, poses potential health risks. We gathered individual well data and public census data across areas of biosolids application and cancer incidence in Pennsylvania. At least one PFAS compound was detected per well for about 65% of the wells evaluated. Statistical analyses of the data showed that PFAS was detected more often in counties with higher percentages of developed land and in counties with lower household incomes and educational levels. Using the statistical results, a county-level map of PFAS detection frequency was created. Because funding limited the total wells sampled to 167 and well locations were influenced by willingness of citizen scientists connected to a state-wide “Master Well Owner Network” communication group and having the time and resources needed to assist with data collection, it is likely that sampled wells may not fully represent the range of conditions across Pennsylvania. Thus, the detection frequency map and the correlation trends from this study provide guidance for designing future well sampling campaigns and identifying locations where well owners may benefit from easier access to testing and mitigation.

Technical Abstract: Due to limited regulation of private wells, individuals who rely on wells as a potable water supply frequently face significant challenges in ensuring safe drinking water. Widespread occurrences of per- and poly-fluoroalkyl substances (PFAS) in groundwater increase these challenges and pose additional threats to public health. Addressing these challenges requires an understanding of the environmental factors influencing PFAS contamination and the socioeconomic conditions that shape access to resources for testing and mitigation. While most studies typically examine environmental or socioeconomic factors in isolation, this study integrates both to provide a more comprehensive understanding of PFAS contamination. Over a three-year period (2021-2023), a community-science campaign tested 167 private wells across Pennsylvania for PFAS. About 20% of the wells were sampled over multiple years to assess variation. Two Tobit models were done: one for environmental factors and one for socioeconomic factors. About 65% of the private wells had detectable levels of PFAS and each compound occurred at least once. Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) were the most frequently detected compounds at 51.5% and 47.3%. Results revealed that 18% of private wells (30) exceeded at least one health-related maximum contaminant level for PFAS. The percentage of developed land was an important environmental factor. Socioeconomic score was positively correlated with PFAS concentration providing insights for future sampling. Results from the repeated individual wells suggest that PFAS vary significantly between sampling events. The findings of this research provide valuable insights into the socioeconomic and environmental factors influencing PFAS occurrence in private wells.