The Groundwater Vulnerability Evaluation Method Based On RSVA Model And The Application Of Beijing Plain

Groundwater is an important part of water resources in China, how to reasonable exploitation and protection of groundwater resources, become an major issue of each region especially the north regions. Groundwater vulnerability assessment is to analysis the possibility of the groundwater pollution in the base of the study of the hydrogeology information .It is an effective means to protect and develop the groundwater.In the research, the article summarized the definitions, the influence factors, the index systems and the common evaluation methods of vulnerability evaluation, and analyzes the characteristics the suitable conditions and their respective limitations of each method.Based on the traits of vulnerability assessment, the article such uses Beijing plain as an example. It uses traditional DRASTIC model and the fuzzy mathematics method and gets the evaluation result diagrams.Combining with the geological features of Beijing plain, it constructs the RSVA model. The new model chooses the recharge, the surface features, the vadose, and the aquifer as its first level factors, and the rainfall discharge, the amount of irrigation, the urban pipeline leakage, the land use types, the river, the terrain gradient, the thickness of soil in vadose, the structure of vadose and the permeability coefficient of aquifer as its second level factors. It uses ahp to determine the weight of the factors as 0.09, 0.06, 0.04, 0.03, 0.09, 0.04, 0.25, 0.26 0.14. Finally it uses weighted summation method and gets the evaluation result diagram.The analysis of the results says that the fuzzy method uses more detailed evaluation data and the evaluation result degree is improved than the traditional method; RSVA model selection index more, the kinds of hydrogeology material are more, and the evaluation result is ideal.