Slope Shape Optimization of Water Reservoirs Formed Due to the Reclamation of Post-Mining Excavations

Reclamation of post-mining areas is one of the most important duties of an entrepreneur involved in mining mineral resources with the use of surface techniques. There are various forms of reclamation activities that depend on the chosen reclamation direction and intended function of the reclaimed object as well as from the type of the mined mineral. When there is water present in the mining excavation, we are talking about the aquatic direction of reclamation. This particular type of post-mining area requires a particular shape—especially if its intended future function is recreational. This research addresses optimization-related analyses and calculations of slope inclination in water reservoirs formed in post-mining excavations of both clastic and clay rock raw materials. Considering the conditions of stability and load-bearing capacity of water reservoir slopes, their optimum slopes were determined using the FlexPDE v 6.0 program, based on a two-dimensional elastoplastic model from the Coulomb–Mohr criterion. The inclinations of 1:5 and 1:15 are proposed, respectively, for the above-waterline and below-waterline slopes that serve a beach function. Slopes that do not serve a beach function are proposed to have an inclination of 1:2. Obviously, the strength conditions in the soil medium as well as the comfort of users were key drivers when it comes to selection of the slope inclinations.