The HydroGeoSphere model presented here was able to successfully simulate the water balance and water quality response of the reclaimed landforms, and the results indicate that the impact of winter processes (i.e., pore-water freeze/thaw) on infiltration and surface runoff are significant. Including freeze-thaw resulted in reduced infiltration during spring melt and reduced salt loading during winter. In total, a 20% reduction of chloride mass release (over an 8-year period) was simulated when freeze-thaw processes were included in the simulations. These results provide a strong argument for the inclusion if winter processes and coupled heat dynamics for detailed studies of integrated hydrologic processes in the Athabasca Oil Sands region.