The Evaluation Of Environmental Quality Of Groundwater In Inland Plains

Water is essential resource on which human beings rely for existence. As an important part of water, groundwater is the main even only source of water of life, industry and agriculture in arid North China and northwest area. With the quick economic development, increasingly population and fast urbanization in recent years, the groundwater is polluted seriously in inland plains. Therefore, we should prevent groundwater pollution so that we can realize the normal water utilization of life, industry and agriculture. This is the primary task to achieve the sustainable utilization of groundwater in inland plains.Taking Yanqi County Plain in Xinjiang as an example, it analyses the chemical types of the groundwater in the study areas with Piper graphic method and the relevance between TDS and content of Na⁺+K⁺, Mg²⁺, Ca²⁺, Cl^-, SO₄^2- and HCO₃^- of unconfined aquifer and confined aquifer.The results show that the relevance between TDS and content of Na⁺+ K+, Mg²⁺, Cl^-and SO₄^2- is better in unconfined aquifer; the relevance between TDS and content of Na++ K⁺, Ca²⁺, Cl^- and SO₄^2-is better in confined water.It uses SPSS software to calculate groundwater environmental background values in order to gain characteristic numbers on groundwater environmental background values. Taking Yanqi County as an environmental unit, it selects seven water quality index such as the K+ + Na+, Ca²⁺, Mg²⁺, Cl^-, SO₄^2-, HCO₃^-, TDS and so on. Index content distribution type are log-normal distribution and normal distribution.It evaluates the shallow groundwater quality in Yanqi County plain using the fuzzy comprehensive evaluation, the results show that the total monitoring wells ofâ… ,â… ,â… ,â… andâ…¤type are respectively 14% , 3%, 24%, 7%, 52%;â… andâ…¤t ype is 59%;,the overall water quality of shallow groundwater is worse.It uses DRAV model to evaluate the vulnerability of groundwater.The results show that: high vulnerability zone locates in the northwest and northeast of the study area (of the total area 21.46%), medium vulnerability areas locat in northwest, northeast and southeast (of the total area 71.74%). Vulnerability assessment results are nearly in line with the distribution of nitrate content. Thus it illustrates the application of DRAV model to evaluate the vulnerability of groundwater quality in Yanji County is feasible.