Status Evaluation And Remediation Research On The Groundwater Pollution In Reclamation Region

In order to solve the double restrictions of resources shortage and structuralshortage of land, the reclaiming process is gradually becoming an effective way toexpand the land space, whose completion would change the hydrodynamic conditionof the coastal zone, the interaction between the groundwater and the sea water anddestroy the original physico-chemical balance of the natural coastal zone. Thedisturbance of human activities would cause serious environmental problems such asseawater intrusion, the penetration of land-sourced pollutant. Hence, it’s necessary tocarry out the groundwater status evaluation, analyze the regularities of pollutantdistribution migration and transformation, and conduct the pollution remediation.Therefore, there are important practical significance and scientific significance tostudy on the ecological restoration of land reclamation zone.In this paper, we confirmed the zone’s hydrogeological characteristics based onthe analysis of the hydro-geological data. According to the principle of geometricsimilarity, we built the physical simulation device in the lab to establish thegroundwater system, which was similar with the system of the simulated area. Afterthe simulation device running steadily, we collected the soil samples to analyze thegrain size and the contaminant. Meanwhile, we collected the water samples to analyzethe pH, oxidation-reduction potential, dissolved oxygen and conductivity. Above all,the water-soil distribution law of total nitrogen, organic matter and heavy metals wereparticularly studied. In this paper, one-dimensional soil column experiment wasconducted. Constant-concentration of sodium chloride (NaCl) was continuouslyintroduced into the columns with dredger fill to acquire the breakthroughcurves(BTCs). The inverse error function method (IEFM) was used for estimatingdispersion coefficient, which was tested in the method of CXTFIT program.According to the distribution law of the contaminant, we chose nitrogen as thespecific pollutant and collected the water samples to monitor the concentration of totalnitrogen, nitrate nitrogen, nitrite nitrogen and ammonium nitrogen. It was found thatnitrogen transformed in various forms and the total nitrogen migrated with the flow ofgroundwater. However, due to the influence of seawater-groundwater interface, thenitrogen transformation in the seawater-groundwater interface location wasinconsonant with the general trends. Finally, according to the distribution and migration law of nitrogen, the microbial bioremediation technology was conducted toremediate the nitrogen pollution of groundwater. Status evaluation and remediationresearch on groundwater pollution in reclamation region would provide importanttheoretical basis for remediating the groundwater and offshore marine seawater andconducting the ecological rehabilitation project.