James Mills, P.E.

Building a Dynamic Conceptual Site Model Using 3D Visualization at a Complex PFAS Site

James Mills, P.E., Project Engineer, Geosyntec Consultants, Inc.

Making informed decisions during PFAS site assessment activities is essential for achieving delineation, reducing uncertainty, and optimizing resource allocation. By integrating advanced tools in site assessment, such as three-dimensional (3D) visualization, practitioners can target priority monitoring zones and refine well placement. 3D visualization is an informative tool for PFAS site assessment, enabling practitioners to move beyond traditional two-dimensional site plan and cross section figures and gain a dynamic, data-driven understanding of contaminant distribution. This approach supports the development of a robust conceptual site model (CSM), allowing for improved visualization of plume geometry and identification of data gaps. By visualizing complex subsurface conditions, 3D visualization enables more efficient well placement and resource allocation. Ultimately, this leads to reduced assessment timelines, reduced overall costs, and provides defensible decision making.  This presentation highlights a Leapfrog Works™ 3D visualization at a complex PFAS site that was developed using over 220 groundwater samples from 110 locations to characterize the spatial extent of PFOA and PFOS in groundwater. The visualization provides insight into horizontal and vertical contaminant migration, highlights the influence of groundwater withdrawals from nearby supply wells, and demonstrates areas where additional monitoring is warranted. The 3D CSM was used to enhance the client’s understanding of subsurface plume geometry, identify potential data gaps in groundwater assessment, and inform the strategic placement of monitoring wells, while delivering an overall cost savings.

James Mills is a licensed Professional Engineer in Geosyntec’s Tampa office with over 8 years of consulting experience. His experience includes PFAS and non-PFAS contamination site assessment, remedial design and implementation, and multi-media field sampling of soil, sediment, surface water, and groundwater for public and private sector clients. His project portfolio includes multiple state-owned PFAS sites in Florida associated with the use of AFFF, and he has managed preliminary investigations through remedial implementation at these sites.