The document discusses a model approach to analyze the effects of Aquifer Thermal Energy Storage (ATES) on mobile contaminant plumes in groundwater systems. The model considers scenarios with and without dense non-aqueous phase liquids (DNAPLs) and degradation. Results show that ATES can initially increase the volume of contaminated groundwater but concentrations decrease over time due to blending and degradation. However, ATES may spread contamination significantly if DNAPLs are present near extraction wells. Further optimization of degradation modeling is needed to fully understand impacts of ATES on contaminated sites.