Pollution Prediction And Control Of Landfills To Groundwater In The West Suburb Of Beijing

Groundwater is very important for Beijing water supply, and the lasting excessive exploitation has coursed a serious geological environment and ecological environment problems. South-to-North Water Diversion Project will solve these problems, but according to the recovery of groundwater, landfills in reception basin may be immersed and groundwater may be seriously polluted. Therefore, predicts the groundwater pollution and presents prevention measurses are very important.The west suburb of Beijing is the study area in this dissertation. The groundwater system was numerically simulated and predicted by a groundwater modeling software （GMS）. Estimate whether and when the landfills are immersed by the simulation results. Then, estimate the possibility of water resources contamination by particle tracing simulation.This dissertation estimate the solute transport model and BP neural network, predict the temporal and spacial distrabution of groundwater concentration, and providing the data for determine the project of groundwater level control. Finally, presents prevention measurses for groundwater concentration.The dissertation made the following results:①Groundwater table in the study area will decline continuously before getting water supply from the South-to-North Water Diversion Project. The water supply from South-to-North Water Diversion Project will lead to a raise in groundwater level of 6.24 m in average, which courses 8 landfills be immersed in the study area.②The hydraulic capture zone is 66.544km2, and landfills in it may course the groundwater resources concentration.③In leaching condition, Cl- isⅠclass water and NO₃⁰- isⅠtoⅡclass water. If landfills be immersed, Cl- isⅠtoⅡclass water and NO₃⁰- isⅠtoⅢclass water in most area andⅣtoⅤclass water near the landfills.④After training, BP neural network can predicts groundwater quality of water resource quickly and simply.⑤Increasing the exploitation of Yangzhuang water resource to 0.204×108m³, groundwater level will 1m lower than the bottom of landfills in study area except Laoshan landfill, and Cl- isⅠclass water and NO₃⁰- isⅠtoⅢclass water afer antiseepage treatment on Laoshan landfill.