FORMATION CAUSES AND CONTROLLING MEASURES OF GROUNDWATER-QUALITY DETERIORATION IN XIEZHOU AREA, YUNCHENG CITY

The groundwater quality in Xiezhou area of Yuncheng city has conspicuously deteriorated in recent years, directly affecting the water supply for the local people daily life and for the agricultural irrigation. The comparison of the hydrogeological condition with the water quality test results in the study area shows that the mass extraction of the groundwater in the mid upper section on fluvial filt plane has lowered the groundwater table and eased the hydraulic gradient. In this case, the extraction of the groundwater near the transitional zone of brackish water has resulted in the lower groundwater table than the niter poor water table, and further in the intrusion of the salt water and further deterioration of the groundwater quality. In order to prevent the further deterioration of groundwater quality and the expansion of the polluted groundwater, the amount of the extracted groundwater and the pumping sections should be controlled.