A Sustainable Approach for Stabilization of Coal Mine Overburden Waste: A Critical Appraisal

The paper reviews the different strengthening techniques to control the displacement of piles of coal overburden wastes. In the present era, the urge for power and minerals is increasing due to rapid growth in industrialization. Thus, extracting minerals buried in the earth require the removal of topsoil or cover if the method involves open-cast mining. This method is only being applicable to minerals that are at shallow depths. Therefore, this method has been active in the industry for the past six decades, which lead to dumping overburden in nearby areas or in-pit. Hence, due to the scarcity of land, the concerned organization is forced to optimize the prior dumping site by increasing height and slope angle. Therefore, strengthening is very important, so it can withstand the additional imposed load generated by coal mine overburden wastes (CMOW). On the other hand, failure of CMOW is a major problem in mining sites, leading to soil erosion, air pollution, and acid mine drainage in those areas. Previously, researchers have proposed various methods of strengthening the CMOW dump using techniques like growing plants on the surface and anchoring the ground due to roots, geosynthetics, lime, cement, and fly ash mixture, etc. Further, the microbial-induced calcite precipitation technique has been established as a natural and beneficial technique in slope stability but has yet to be researched for its applicability in strengthening CMOW dumps in mining areas. Hence, the key motive of this review paper is to bring out various aspects of CMOW, such as status, scenarios, associated challenges, engineering properties, techniques to strengthen, and future action plans to adopt a novel method to overcome issues.