Multi-criteria analysis of the possibility of retrofitting the system of rainwater drainage from subsidence basins in a liquidated mine.

Mine closure is the natural final stage of mining activity. The process of financing mine liquidation is complex and expensive. The many years of conducted hard coal extraction affect the surface height differences. Analyses of the shifts in hydrogeological conditions and water hazard states in mining plants led to legal regulation adaptations, primarily in terms of hydrogeological documentation preparation, and made it necessary to conduct work concerning new options for water hazard assessment and prevention. Current subjects of particular interest include shifts in terrain morphology and the water regime, resulting in periodic flooding and permanent flooding of the most depressed areas as well as changes in the directions and intensity of surface water flows. This publication presents a multi-criteria analysis of the possibility of reducing the liquidation costs of an inactive mine through the retrofitting of the existing system of rainwater drainage from subsidence basins. The analysis revealed the primary factors disrupting the course of the drainage process and the problems resulting from them. Technically feasible solutions is presented, together with their assessment. Applying the multi-criteria analysis made it possible to select optimal solutions from a group of proposed technical system retrofitting variants