Hydrogeek developed a 3D groundwater flow model for transient mine inflow estimates for two large open pit mines. The model capitalizes on FEFLOW flexible meshing options and refinement to handle complex
geology (3 aquifers and 4 aquicludes) and dewatering wells. The model heads were calibrated based on historical abstraction from 13 dewatering wells over 10 years with daily abstraction rates.
The project relied on the ability of the model to predict future groundwater and residual inflows. A combination of planned dewatering wells and horizonal drain wells were used, targeting the major aquifer outside the pit and lower conductive units. The aim of the model was to lower heads below mining levels.
The model was able to be simple and robust and provided meaningful observations for the client, to inform future water management decisions.