Influence of coal mining on phreatic aquifer and its environmentaleffects in Yulin-Shenmu-Fugu Area

In order to study the influence of coal mining on the aquifer in Yulin-Shenmu-Fugu Area and protect groundwater resources,analyzed the present situation of aquifer in Yulin-Shenmu-Fugu Area through data collection and field investigation．The results showed that high-intensity mining was the main driving factor for the decrease of lake area,the dry surface water and the decline of groundwater level．By the beginning of 2015,the area of goaf was 4.73×104 hm2 and the area of ground subsidence was about 1.34×104 hm2 in Yulin-Shenmu-Fugu Area.The goaf area increased the thickness of the gas zone and the evaporation of water,reduced the supply of aquifers,and increased the vertical runoff to form a natural-artificial superposition of groundwater flow．The environmental effected performance that lake area reduction was nearly 50%,part of the surface water dried up,the amount of spring decay rate was 84%,spring water flow decay rate was 70%,the evolution of hydrophilous vegetation to xerophyte the ecological environment tended to be fragile.