Prediction and maintenance of water resources carrying capacity in mining area-A case study in the Yu-Shen Mining area

Abstract

The problem of water resources damage caused by coal mining has restricted the sustainable development of Yu-Shen mining area. Illustrating the relationship between mining and water resources carrying capacity is of great significance to solve this problem. In this study, the authors proposed an appraisal and prediction model of water resource carrying capacity in the mining area (WRCCMA) based on the analytic hierarchy process (AHP)-fuzzy comprehensive evaluation method. A triple-leveled structure model was developed, and the main influencing factors of the WRCCMA and the membership functions were analyzed. The prediction model was applied to Yubujie colliery to test its validity by investigating the changes of vegetation coverage and the ground deformation of the colliery and its adjacent coal mine before and after mining. Subsequently, we obtained the WRCCMA of the study area and zoning map of different grades of WRCCMA in the mining area by applying this model to the whole Yu-Shen mining area. Furthermore, three countermeasures to maintain the WRCCMA and realize water conservation coal mining (WCCM) were provided to collieries with different WRCCMA grades, including mining methods selection, mine water reutilization, and water-resisting layer reconstruction. Reasonable mining methods and water-resisting layer reconstruction can reduce the development of water conductive fractures and thus prevent groundwater from penetrating into the goaf. Mine water reutilization provides a source of water demand for collieries and families, contributing to the reduction of abstraction of water resources. These three countermeasures can help to maintain the WRCCMA. This paper successfully combines the fuzzy theory with mining engineering and provides theoretical and practical guidance for other mining areas in arid and semi-arid regions of Northwest China.