Perkova T. The patterns of physical-chemical changes in rocks below impoundments of mineralized mine water.

The thesis aims to identify the patterns of changes of permeability and geomechanical properties of rocks below mine water impoundments and tailings caused by leaks and transport of mineralized mine water. This creates the theoretical basis to evaluate parameters of engineering solutions in order to localize hydrodynamical and physical-chemical impacts of mine water impoundments and tailings on rocks to prevent from flow-induced deformation of rocks. The zone of hydrodynamical and physical-chemical changes in rocks induced by mineralized water seepage through impoundments and tailings has been estimated on the example of sites located in Central Ukraine by means of numerical simulation of variable density flow and transport. It is established that the physical-chemical interactions between mine water and clay loam at the bottom of impoundments at high hydraulic gradients increase water flow velocities, which is described by cubical parabola. This, in turn, leads to increasing permeability of loam and changes its physical and mechanical properties. The kinetical parameter of leaching Ca2+ ions from organic limestone as a result of mineralized mine water transport has been evaluated experimentally; this allows assessing adequately the scale of man-caused karst in carbonate rocks. The engineering solution to mitigate the impacts of tailing facilities on rocks by preventing flow-induced deformation of the impoundment bottom has been substantiated.