Assessment of Groundwater Pollution and its Causes in the Plain Area of Yili River Valley

Abstract

This paper, adapting the method of Average Comprehensive Pollution Index and Nemero Pollution Index, aims to evaluate the groundwater pollution of the plain area of Yili river valley in Xinjiang uygur autonomous region. And the cause of the pollution was discussed as well. The results showed that: First, the main influencing factors are total hardness, sulfate, as well as three nitrogen. Second, the main reasons for the groundwater pollution are industrial and mining enterprises which present star-like in this area. What’s more, the domestic sewage with zonal distribution and the planar distribution of agricultural waste water are also included. This study is of great importance to the analysis and prediction of groundwater environmental impact. Located in the northwest of Xinjiang uygur autonomous region, with its most humid climate, the most abundant precipitation as well as the richest soil and coverage of vegetation within the area of Xinjiang and Tianshan, the Yili river valley has been hailed as the “wet island” and “treasure of biological resources” of the semi arid region [1]. Yili river valley is rich in water resources. And main river that it flows through is the Yili River, an international river that runs across China and Kazakhstan, the total length of which is 1236.5 km, with its length at home 442km[2]. The present researches on the Yili river valley is relatively poor, with the materials relating to the water environment not so rich [3-8]. With the influence of human activities, the flow field, water quality and hydro-chemical characteristics of groundwater in this area have been changed accordingly. The evaluation of contaminated situation of groundwater in this area can provide a sound scientific basis for the rational utilization of water resources in this region. Meanwhile, it works as a solid guide for the sustainable development and integrated management of water resources within this region [9].