DYNTRACK is the primary companion mass transport model for DYNFLOW. DYNTRACK inputs flow fields from DYNFLOW, and simulates dissolved contaminant fate and transport in 3D aquifer systems, using the random walk method. DYNTRACK also performs particle tracking, and has the ability to "backtrack" for such purposes as defining zones-of-capture of pumping wells.
In the plume simulation mode, DYNTRACK simulates advection, dispersion, molecular diffusion, first-order decay, and adsorption/ retardation. In addition, it has an associated module called DYNOPT used in the calibration phase to estimate the contribution from the different source locations and time periods.