The Geospatial Distribution of PFAS on the West Plains of Spokane County, Washington
Faculty Mentor
Chad Pritchard
Presentation Type
Poster
Start Date
4-14-2026 11:30 AM
End Date
4-14-2026 1:30 PM
Location
PUB NCR
Primary Discipline of Presentation
Geosciences
Abstract
About 700 groundwater samples collected across the West Plains of Spokane County by the EPA and Eastern Washington University were analyzed for per- and polyfluoroalkyl substances (PFAS) using EPA Method 533. Additionally, the Fairchild Air Force Base and Spokane international Airport remedial investigation reports added another 50 wells at the main PFAS sources for the West Plains. Our preliminary mapping included about 300 wells, so the additional results from the late 2024 and 2025 summer field season over doubled the amount of groundwater locations and PFAS results, as well as filling in “data deserts” or spatial gaps in the West Plains. Using available PFAS results and well‑construction data, geospatial concentration maps were developed to illustrate the distribution of PFOS and PFHxS—compounds commonly associated with historical firefighting foams, aqueous foam forming film (AFFF) usage—as well as PFOA, which is more broadly linked to contamination from commercial products such as automotive fluids and septic systems. These maps reveal distinct PFAS hotspots near Fairchild Air Force Base and the Spokane International Airport, areas with known AFFF application. This project provides an updated assessment of PFAS distribution across the West Plains using newly collected groundwater samples from the summer of 2025, which drastically increased the resolution for projecting PFAS concentrations in the West Plains.
Recommended Citation
Slanga, Emersen, "The Geospatial Distribution of PFAS on the West Plains of Spokane County, Washington" (2026). 2026 Symposium. 5.
https://dc.ewu.edu/srcw_2026/ps_2026/p2_2026/5
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
The Geospatial Distribution of PFAS on the West Plains of Spokane County, Washington
PUB NCR
About 700 groundwater samples collected across the West Plains of Spokane County by the EPA and Eastern Washington University were analyzed for per- and polyfluoroalkyl substances (PFAS) using EPA Method 533. Additionally, the Fairchild Air Force Base and Spokane international Airport remedial investigation reports added another 50 wells at the main PFAS sources for the West Plains. Our preliminary mapping included about 300 wells, so the additional results from the late 2024 and 2025 summer field season over doubled the amount of groundwater locations and PFAS results, as well as filling in “data deserts” or spatial gaps in the West Plains. Using available PFAS results and well‑construction data, geospatial concentration maps were developed to illustrate the distribution of PFOS and PFHxS—compounds commonly associated with historical firefighting foams, aqueous foam forming film (AFFF) usage—as well as PFOA, which is more broadly linked to contamination from commercial products such as automotive fluids and septic systems. These maps reveal distinct PFAS hotspots near Fairchild Air Force Base and the Spokane International Airport, areas with known AFFF application. This project provides an updated assessment of PFAS distribution across the West Plains using newly collected groundwater samples from the summer of 2025, which drastically increased the resolution for projecting PFAS concentrations in the West Plains.
