Assessment of environmental and technical risks in the process of mining on the basis of numerical simulation of geofiltration

Purpose. Substantiation of environmentally acceptable and technically safe operational mining schemes in the context of disturbed hydrogeological and geomechanical conditions by means of developing adapted filtrational model of the mine field. Methods. Numerical mathematical stimulation of geofiltrational processes in heterogeneous in terms of capacitivity and permeability rock massif involving surface-water and underground water dependency, leakage through partitioning poor water-permeable strata, as well as changes in boundary conditions and geofiltrational parameters in the context of time and space. Findings. Hydrodynamic model of the mine field has been identified with the help of imitating technogenic ground water dynamics formed during different periods of mine operation. Its reliability has been confirmed by the results of predicted solutions concerning estimation of inflow values within high-amplitude tectonic disturbance having high level of convergence with actual data while roadheading (up to 95%). The effect of mining operations as well as operation of mine water gathering pond on underground water dynamics of subsurface water-bearing formation which determines both environmental situation and water use, has been numerically estimated. Originality. Regularities of changes in filtrational parameters and capacity parameters in terms of time and space under the conditions of nonstationary geodynamics of rock massif have been specified. Elastic hydrodynamic disturbances with values of compressibility and permeability comparable to undisturbed poor water-permeable rock massif consisting of argillites, aleurites, and arenites have been determined for a zone of tectonic disturbance. Practical implications. The determined rules concerning formation of ground water dynamics of subsurface water-bearing system make it possible to differentiate natural components and technogenic components in the context of disturbance of hydrogeo-chemical composition of ground water used for water supply and specify parameters of water intake. High reliability of predicted solutions has helped substantiate and implement specific hydrogeomonitoring of crossdrift drawing through tectonic fault zone where amplitude is more than 300 m and prevent mine water inflows incidences at minimum costs.