Determining of safety pillars in the vicinity of water reservoirs in mine workings within abandoned mines in the Upper Silesian Coal Basin (USCB)

Against a background of hydrodynamic conditions connected with abandoning of significant number of mines and vast water reservoirs forming within them, basic methods of the assessment of strength of safety pillars used in coal mines in the USCB are presented. In the light of geomechanical research and conditions in mines in the USCB, the paper indicates a possibility of verification of safety pillar dimensions. On the example of one of mines in the USCB conditions for safety pillars stability in complicated mining conditions are assessed. The author also proposes a methodology of attempt and safety zones indication for existing safety pillars which would simultaneously be safety zones for designed exploitation.