Paper Title
Theoretical Research and Engineering Practice of Water-Preserved Coal Mining

Abstract
In semiarid-arid northwest China，there are shallow buried, large thickness coal, but short water and vulnerable environment. For basic theory, the zone law of water flowing fractured is about 25 times mining thickness. The ecological diving is also affected by leakage and mining subsidence. When the level of ecological diving is 1~5m, the ecological environment is fine. For engineering practice, the groundwater flow field had been explored by high-precision instrument (flow velocity accuracy 0.01 μm/s). The water flowing fractured had been explored by MCI. Mining subsidence area had been repaired by the goaf water. Keywords - Water-Preserved Coal Mining, the Zone of Water Flowing Fractured, Water Resources, Ecology, Mine Water