Institute: South Dakota
Year Established: 2020 Start Date: 2020-03-01 End Date: 2021-02-28
Total Federal Funds: $10,000 Total Non-Federal Funds: $20,000
Principal Investigators: Mengistu Geza Nisrani
Abstract: Approximately 25 percent of South Dakota residents rely upon on-site septic systems for wastewater treatment. About 90 percent of Rapid Cityâ€™s drinking water originates from groundwater in the Madison aquifer. The Madison aquifer is composed of limestone and dolomite, and is karstic, highly permeable and heterogeneous. Two of the hydrogeologic settings in the Black Hills area are alluvial deposits and karst limestone formations. These aquifers provide the largest single source of drinking water in the Black Hills; however, because of their karstic characteristics, recharge areas for these aquifers are sensitive to contamination. Various studies have indicated that there are several potential sources of contamination in recharge water for the Madison aquifer, including wildlife, livestock, and septic systems. While there is some knowledge of contaminant sources for the groundwater in the aquifer, there is little understanding about contaminant flow paths and potential risks.The goal of this study is to assess the potential for groundwater and surface water contamination from septic systems on a watershed scale under vulnerable soil, geological settings, and climate conditions using coefficients generated in year 1. The study will focus on nutrient loading (nitrogen and phosphorus).The watershed scale assessment includes; building a watershed model, model calibration, parameter sensitivity analysis, and scenario analysis.