Reactive transport modeling for supporting climate resilience at groundwater contamination sites

Abstract. Climate resilience is an emerging issue at contaminated sites and hazardous waste sites, since projected climate shifts (e.g., increased/decreased precipitation) extreme events flooding, drought) could affect ongoing remediation or closure strategies. In this study, we develop a reactive transport model (Amanzi) for radionuclides (uranium, tritium, others) evaluate how different scenarios under change will influence the contaminant plume conditions groundwater well concentrations. We demonstrate our approach using two-dimensional (2D) Savannah River Site F-Area, including mineral reaction sorption processes. Different recharge are considered by perturbing infiltration rate from base case as considering cap-failure projection scenarios. also uranium nitrate concentration ratios between to isolate effects with changing rates. The modeling results indicate that competing of dilution remobilization significantly pH, thus uranium. At maximum on breakthrough curve, higher aqueous implies reduced lower pH due remobilization. To better impacts in future, workflow include downscaled CMIP5 (Coupled Model Intercomparison Project) data residual contamination evolves through 2100 four Representative Concentration Pathway (RCP) integration hydrogeochemistry models enables us quantify impacts, assess which need be planned for, therefore assist resiliency efforts help guide site management.