Study On Modeling Of Seawater Intruding Into Groundwater In Weihai

Due to changes of coastal groundwater dynamics, seawater moving toward into inland fresh groundwater aquifer results in seawater intrusion. With the increase of groundwater pumping since 1980s, seawater intrusion in the costal regions of China has severely deteriorated fresh water quality. Many research results for seawater intrusion modeling in China were suitable for specific problems and small areas and universal modeling system has not developed because of the complicated mechanism and influence factors of the seawater intrusion. This study was focused on development of a universal model and field application.The advanced theories of the seawater intrusion were introduced in this paper. A typical potential function was used for analyzing the sharp interface position and influencing factors of the seawater intrusion. The Weihai Torch Hi-tech Science field was selected in this study. Groundwater intrusion extent and area were distinguished by the environmental isotope technique and groundwater quality analysis. The model parameters were firstly determined as reference values of field modeling using soil column experiment at laboratory based on the one demontional variable-density solute transport model. A 3-D numerical modeling system was developed based on the saturated-unsaturated groundwater flow and solute transport model (SUTRA). The model parameters were further calibrated and validated against observation data of groundwater table and Cl- concentration. The simulated results demonstrated that simulated groundwater level and Cl concentrations agree well with the observed data, This indicates that the model is reliable and can be used to simulate groundwater flow and solute transport in the coastal aquifers. The established modeling system offers a good tool for groundwater resources management and environmental protection in the coastal region.