Abstract: Because of not being done anti-seepage treatment, the leachate containing phosphorus and fluorine produced by the phosphogypsum yard of Pingba enter the surrounding systems of surface water and groundwater though the sewage drains, karst pipes and cracks. The leachate contaminat water of Yangchang River and affected the water environment of Hongfeng Reservoir. In this paper, the development of joint and karst were found out, the hydraulic connection between the surface water and ground water were analyzed, the channel of the leachate flowing into the Yangchang River is 02 aqueduct and the rode from 01 aqueduct and L1 to Q16 and jointed rock mass, the pollution of groundwater subject to jointed surface which main direction is north and west, this were based on the methods of hydro-geological survey and statistical inquiry of quadrat and water-pressure test and connection test. Through the water sample monitor, the scope and extent of water pollution were delimited. Finally, the pollution prevention and control measures such as vertical and horizontal seepage and drainage collection and surface coverage were put out.