Researching Of Underground Water Environment Restoration In Seawater Intrusion Area

First, this paper generalizes the domestic and overseas researching measures and status quo about seawater intrusion. The paper summarizes all of those in Dalian, and puts forward new contents and measures.The paper analyses the way and the track of seawater intrusion, and influencing factors and disasters caused by that in Nanguanling of Dalian City. Finally, it researches the process which has last for 40 years and trend of seawater intrusion. The result shows the the underground water environment has restored basically. Based on summarizing the reason of that, we put forward the advices about how to restore the underground water environment further. The analysis shows that there are three types of seawater intrusion in Dalian City: area-form intrusion, linear-form intrusion and cavity-shape intrusion. The ways of intrusion are karst fissure, structural fracture and the intrusion in contact-zone of diabase and rock. Influencing factors of seawater intrusion are as follow: geology and hydrogeology are the geological background for the seawater intrusion; human irrational projects such as economic activities are the main factor of seawater intrusion. According to the exploitation of underground water in the researching area, we define four stages of seawater intrusion: unintrusion stage, slight intrusion stage, serious intrusion stage and restoration stage. The trend of seawater is that the intrusion area varies as following rule: small to big to small; the intrusion distance: anear to far to anear. The condition of seawater intrusion has improved. The main reasons of the restoration of underground environment in the researching area are as follow: adjustment of industry structure, improvement of shills in industry and agriculture and long-distance water transfer project. Finally, we put forward some advices which are offing controling exploitation, regional cascade storage, exploitation alternative, closure and exploitation and strengthening the legal management, to further restore the underground water environment in the seawater intrusion area.