The influence of mining induced subsidence on groundwater resources

An approach is developed to quantify the impact of longwall mining on the potential disruption of groundwater resources. The underlying premise of the method is to assume that the primary mechanism causing dewatering is the development of new fractures or the dilation of existing fractures, as a result of mining induced displacements. From this assumption it is possible to evaluate the potential influence on groundwater resources. Numerical simulation, using the finite element method, is used to both determine the mining induced distribution in strain and to complete hydrologic budget calculations with the revised conductivity field. Results indicate that observed trends in dewatering behaviour may be explained on the basis of zones of contiguous extensile strain, induced within the overburden as a result of mining. -from Authors