Research Of The Optimization On Restoration Schemes Of Saline Groundwater At The Low Reach Of Dagu River

This paper is accomplished on the basis of key scientific and technological project of Qingdao City-The Study of Pollution Control and Optimized Utilization of Water Resource in Dagu River.With the development of economy and the increasing of population, it is required more and more water to exploit in Qingdao City as well as it's surrounding area, which results in the descending of groundwater level and seawater intrusion.Based on analyzing and approximating the graphic and hydrogeologic conditions of the saline water distribution area, a solute numerical model is set up by generalizing the hydrogeology conditions of the study area, and different restoration schemes are simulated and analyzed using groundwater simulation software-Visual-MODFLOW 3.1.The simulating results indicate, it is required much more time to remove the saline groundwater completely than the intrusion process does, and there is a great deal of saline water remained even after 36 months. It is a crucial factor to select the proper restoration schemes, of which the natural and recharging scheme is unfeasible, the pumping one is only efficient to remove the high concentration saline groundwater and the low concentration one remains, while the pumping-recharging and optimizing ones have a high efficiency both to the high and low concentration saline water.In all of the restoration schemes, there is so little new saline water enter the distribution area from the upper of impervious wall that it can not affect the results of the model, and it is important for preventing the intrusion of the sea water and saline groundwater of the low reach.