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Fresh and salt water miscible fluid, appears due to hydrodynamic dispersion effect, the contact zone between them to form the transition zone of the mixed water, i.e. salt - fresh water transition zone. Hydrogeological conditions in the coastal, natural and human factors will affect the distribution and morphology of the brackish water transition zone, to determine the dynamic characteristics of the distribution of saline groundwater in an aqueous medium. Due to excessive exploitation of underground water, sea salt water intrusion has become a serious phenomenon of geological disasters in the coastal areas in many areas has also taken the corresponding control measures. Therefore, in-depth study of the feasibility of saline groundwater distribution of the dynamic characteristics and governance, have a very important theoretical significance and practical value for the rational development, utilization of groundwater resources and saltwater intrusion prediction and prevention. Site hydrogeological investigation on the basis of measured in the study area (Qingdao Dagu River downstream) an aqueous medium, the physical and chemical properties and composition of the water samples. By the the rainfall tests carried out in the soil column and sand tank to analyze the dynamic characteristics of the rainfall intensity and distribution of different salt concentration of salt water; mutations and salinity gradient salinity brackish water flooding the sand tank test, brackish water chemotactic alternate water sensitivity phenomenon, in-depth to explore the mechanism and laws of the aqueous medium permeability change; soil column and sand tank test, flow velocity, into the water salt concentration and governance of underground the effect of salt water governance, under the influence of various factors, the feasibility of salt water governance. Through all these studies, reached the following understanding and conclusions, including: (1) rainfall intensity on the upper aqueous medium salt concentration greater impact, after the rain stopped, the the upper aqueous medium salt concentration due to the role of molecular diffusion will be the rise, storm intensity, the recovery rate of the salt concentration of the aqueous medium upper; rainfall on the trend of the salt concentration of the aqueous medium did not affect only affect its rate of change and variation; initial salt concentration of aqueous medium, the lower , the greater the rainfall suffered the impact of changes in the salt concentration. (2) In the process of salt and fresh water flooding, salinity mutation process and salinity gradual process of permeability change mechanism. Permeability drastically reduced salinity mutation process, mainly caused due to the release of particles adjacent pores connecting passage blocking occurs, the interrupt caused; salinity gradients process permeability decreases, the clay mineral content may be less reactive (such as montmorillonite) volume increases, leading to reduction in the effective cross-sectional area of ??the pore of the results. (3) an aqueous medium permeability changes with significant heterogeneity, which is located away into the water at different horizontal distance and height at the aqueous medium, the permeability variation different. (4) Note the short drive salty pass into fresh water, the greater the flow velocity, the clay, the easier from pore wall off and release, clay release also increased, making the aqueous medium permeability decline also greater. The injected NaCl concentration, the lower and injected into the NaCl concentration gradient of diminishing the greater, the cosmid more prone to release, the greater the aqueous medium permeability decline. (5) compared with the full well, the use of incomplete wells, salt water recovery and management of, aqueous medium permeability changed little. But at the same time the rate of change of the salt concentration was significantly slowed down, governance required a longer time. (6) - Note association scheme recovery and management of saline groundwater pumping, water seepage salt concentration change rate. The same time as the flow velocity is not conducive to the release of clay particle deposition, and may even makes the original clogged pores again rushed to open, so that the permeability decline slightly smaller than a single injection program. Therefore, the use of sampling - Note association scheme governance required for a short time and small to the aqueous medium permeability damage, is ideal salt water recovery and management programs.
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