Assessment of post-mining terrain suitability for economic use

Upper Silesian Coal Basin in Poland is subjected to underground mining for several hundreds of years. Due to intensive extraction, land surface has been widely transformed, causing a lot of mining damages. Of great importance is the issue of recovering the surface to its previous conditions after mining activity is finished. In specific conditions, a threat of mining damages may rest for several years after mine closure. In this paper, some chosen issues connected with assessment of post-mining terrain suitability for economic use have been discussed. Two important elements of such threat have been described: determining the possibility of discontinuous deformations creation and the evaluation of active subsidence process duration. In the introductory part of the paper some theoretical base has been given. Next, the example of probability assessment of sinkhole creation has been presented, together with determination of subsidence process cease time. For determination of subsidence process duration, own empirical formulas have been utilized. They can be used in cases, when there is a lack of survey results from the area of interest.