Research On The Cl~- Time-space Migration Characteristics Of Soil And Groundwater Between Two Drainage Rivers

With the increasing of the quantity and the scale of industrial and mining enterprises,industrial agglomeration area is the important part to adjust city structure and to promote society virtuous circle,but causes easily surface water pollution in the rivers.Surface water infiltration leads to groundwater pollution in the leakage area,which influences the human production and life.Based on the analysis of the Clspace-time distribution characteristics,the thesis studied the Cl~-time-space migration characteristics of soil and groundwater between two drainage rivers,the results can provide the references for groundwater quality control and effect evaluation.Firstly,the thesis studied the Cl~-space-time distribution characteristics of two drainage rivers by analyzing eight surface water samples.Cl~-content in surface water decreased along two rivers,the decreasing range in Dashihe river was more than Baimamen river,and Cl~-content in surface water decreased generally with sampling time going.The surface elevation and the groundwater level were measured in the study area,and the terrain was high in the northwest and low in the southeast.The groundwater level was high in the west and low in the east in general,and raise gradually to tend to stability with sampling time going.Secondly,the thesis studied the Cl~-space-time distribution characteristics of groundwater and the relationship with the drainage river by the monitoring thirty-nine groundwater samples.Dashi river water effection on groundwater was more than Baimamen river.Cl~-content in groundwater decreased gradually with sampling time going.The surface-water effection on groundwater was obvious in the vertical to two rivers.The farther the distance to Dashi river was,the less Cl~-content in groundwater was,and Cl~-content in groundwater lagged behind surface water.Twenty-six soil sampling points were layouted in the study area,soil samples were collected from different depth in every point to analyze the relationships between the drainage river and the soil space-time distribution characteristics of Cl~-and water contents in horizontal and vertical directions respectively.Cl~-and water contents in soil decreased from the south to the north,the larger the sampling depth,the more Cl~-content,and Clcontent was positive correlation with water content.The Cl~-space-time distribution characteristics of soil and groundwater were studied in different Cl~-content surface water by soil column experiments.When surface water with the lower Cl~-content leached higher Cl~-content soil,the farther the distance to surface water was,the more Cl~-content was.When surface water with the higher Cl~-content leached transparent soil,the farther the distance to surface water was,the less Cl~-content was.And both of them tend to the Cl~-content in surface water.Finally,based on field tests,laboratory experiments and theoretical analysis,the conception of Cl~-retardant strength was provided,the recognition model of river-surface-water seepage zone were produced,and the seepage ranges of two river were calculated.Due to the soil characteristics in surface seepage zone,the surface leakage process was analyzed,the combination mathematical model of Cl~-migration was established,and the control mechanism of Cl~-migration was provided.The basic prediction mode on groundwater pollution controlling was discussed,prediction model of groundwater quality were established,and the example analysis were operated.The calculation results showed that,without considering the weather,the groundwater Clcontent reaching to “groundwater drinking water quality standard” ? level were in 3 days,217 days and 721 days respectively to last groundwater sample being collected in the Beizhu village well No.4,the north well in Zhaodian village and D1-1 sampling point.