GIS-Based PFAS Risk Evaluation Toolkit

Weston & Sampson assisted the Connecticut Department of Energy and Environmental Protection (CTDEEP) in developing a comprehensive GIS-based toolkit to evaluate relative PFAS release risks across the state.

The toolkit, designed as a web app hosted in CTDEEP’s ArcGIS Online organization, consolidated data from federal, state, and local sources, with additional proprietary data published for internal use. It featured a project-specific query tool to screen potential risks to sensitive receptors using multiple database layers. This enabled CTDEEP to prioritize sampling based on PFAS contamination risk, identifying areas with the highest number of NAICS users within each source protection area. Queries could be refined using parameters such as gravel soils, distance from supply wells, and topography. CTDEEP has used the toolkit to locate potential PFAS sources, assess surface water and fish tissue impacts, and identify treatment works likely receiving PFAS discharges.