Abstract: On the basis of author’s two on-the-spot consultant experiences and the collected data, this paper discusses ecological environment problems, such as groundwater resources loss, poor coal-measure water intrusion and hydrologic cycle unbalance, which are caused by discharge from the tunnel, and their formation mechanisms. It also discusses a series of negative effects resulted, such as karst spring water depletion, groundwater degradation, surface water pollution and soil erosion. Analysis results showthat the long-term discharge of the tunnel will produce large-scale cone of depression, and that the expansion of the cone will lead to the happening of intense hydrogeochemical action in drainage belt, hence bringing a threat to the stability of the tunnel lining.