Sustainable groundwater management is a worldwide challenge. Numerical modelling is one such tool which addresses this challenge. Regional-scale modelling of groundwater flow is necessary for planning and management of groundwater resources. The aim of the study is to numerically model the groundwater flow in Medapalli Open cast block area. Medapalli Open Cast Block is a coal mine operating under Singareni Collieries Company Limited SCCL in Telangana, India. It is spread across and lies near river Godavari. The observation well locations and depth to water level data are collected from SCCL. A finite-difference based groundwater flow model is developed in Visual MODFLOW using MODFLOW-2005 code with forty conceptual layers and with a total thickness of 240 m. The model is constructed based on the geological and spatial data of the study area. The model calibration is performed at steady state conditions through trial and error method. In addition to this, a solute transport model is developed using MT3DMS code at steady state conditions. The results indicate that the computed water table values fairly match the observed water table values and the simulated flow direction is towards the river Godavari, in accordance with the field conditions and following the general topography of the region. The solute, i.e. (TDS) migration extends up to a maximum distance of 168 m along the periphery of Medapalli open cast block towards the river. The study shows that the impact of fly ash deposition in Medapalli Open cast mine on the groundwater quality in the vicinity of the open pit will be very less and no harmful effects will be observed as the contaminant levels decrease steeply along the periphery of the mine and concentration of the plume is reduced sharply.
Keywords: Groundwater flow Model, Visual MODFLOW, Medapalli Open Cast block, solute transport, Numerical Modelling