Darcy flux and PFAS mass flux in groundwater at Yakima Training Center, Washington

This U.S. Geological Survey (USGS) data release contains Darcy flux and mass flux of per- and polyfluoroalkyl substances (PFAS) data measured using passive flux meters (PFMs) in monitoring wells at the Yakima Training Center (YTC) in Yakima, Washington. The measurements were conducted by the USGS in cooperation with the U.S. Army Environmental Command. This data release contains PFM data from two deployments: a pilot study of 2 wells during July-August 2025, and a second deployment of 12 wells during September 2025. Note: Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.