The influence of shallow coal seam mining on groundwater circulation migration and protection measures

ABSTRACT Clarifying the influence characteristics of coal mining on groundwater migration is the foundation for formulating water resource protection measures. By means of physical simulation, theoretical analysis and field observation, the distribution of water-conducting fractures in overlying strata and their influence on groundwater circulation and migration in shallow coal seam mining of Daliuta coal mine during the period from 2010 to 2012 were studied. The results show that the mining-induced fractures in the multi-coal seam mining connected the surface and the goafs of each coal seam, and the fracture-rich areas on both sides of the mining boundary of the working face were the main channels of groundwater seepage. Coal mining will form a groundwater funnel with the goaf as the groundwater discharge area and the water-conducting fracture zone (WCFZ) as the seepage channel, which changes the water circulation mode from the pre-mining lateral seepage to the post-mining vertical seepage. The groundwater flow field in the mining process of No. 20601 working face has changed significantly compared with that before mining, forming a drainage area centered on the goaf. Mine water can be stored by building coal mine underground reservoirs, which can effectively protect the water resources.