Numerical simulation of groundwater flow field evolution in abandoned mine in the east Xuzhou

Based on the study of the abandoned mine in the east of Xuzhou, the evolution of Taiyuan Formation Aquifer groundwater movement has been detected through the establishment of groundwater system model in abandoned mine area and the study of the evolution of regional groundwater dynamic field using numerical simulation technology. It can be seemed that before the coal mine closed it has to drain away a lot of groundwater for the use of living and producing. So in the diggings there are various cones of depression, such as Qingshanquan coal mine and Hanqiao coal mine whose groundwater levels are below minus 25 meters in the cone centers. After the mine closed, all the drainage systems stopped and the groundwater level rises slowly, as well as the scope of depression cones. The rate of the level raising has become more and more slowly since the mine closed according to the simulation. In the first year after the mine closed, the rate will be 1.14 meters per year. Two years later, the rate will drop to 0.165 meters per year. By the time the mine has been closed for 10 years, the top groundwater level will have reached minus 16.55 meters while the rate will have decreased to 0.039 meters per year. Groundwater system of the coal mine will regain to a stable flow field which is the north to the south.