MODPATH model to simulate backward particle tracking in groundwater near Puget Sound, Pierce County, Washington

Backward particle tracking in groundwater was simulated with MODPATH and the MODFLOW groundwater flow model by Long and others (2024). Simulated particles were tracked backward from well intakes in areas within or near Joint Base Lewis-McChord (JBLM) for the purpose of determining their likely points of origin within groundwater recharge areas. Steady-state and transient simulations were performed, with transient simulations representing monthly changes for 2005-2015. This data release contains the input and output files for the simulations.