Analysis Of Groundwater Environmental Impact For Guyuan Light Industrial Park,Ningxia

In order to implement “The environmental protection law of the People’s Republic of China”, “Water pollution prevention law of the People’s Republic of China” and “The Environment Impact Assessment law of the People’s Republic of China”. “Technical guidelines for environmental impact assessment-Groundwater environment”were published on February 11, 2011 by The ministry of environmental protection to standardize and guide the groundwater environment impact assessment work, protect the environment, prevention and control of groundwater pollution. The standard specifies the general principles, contents, work procedures, methods and requirements of environmental impact assessment for ground water, it apply to groundwater which as water supply source and environmental impact assessment of construction projects which may influence the groundwater environment.Guyuan light industrial park is a new project which deployed according to Guyuan salt chemical industry circulation economy with demonstration zone for poverty alleviation master planning. According to “ordinance on administration for environmental protection of construction projects”(State council order no. 253, 1998), “list of classified management of the construction project environmental impact assessment”(The Ministry of Environmental Protection NO.33) and“Technical guidelines for environmental impact assessment-Groundwater environment”(HJ 610-2011), groundwater environmental impact assessment must be carried out before the project implementation.On the basis of analyzing regional geological and hydrogeological data, detailed hydrogeology survey work has been carried out in the project area. To find out aquifer lithology, distribution, structure, thickness, buried conditions, permeability, etc.; Combined with hydrogeological exploration method, the types of groundwater, the conditons of recharge and runoff and draining as well as the characteristics of flow field were found out; Vadose zone lithology, structure, thickness, distribution were found out, vertical permeability is identified by vadose zone seepage test; By analyzing water quality sampling, we found out the hydrochemical characteristics of groundwater, and the groundwater environmental quality status assessment is completed. Then analytical method was used to evaluate groundwater environmental quality, and aimed at the evaluation results, the corresponding prevention measures and Suggestions were putted forward.The specific research results of this paper are mainly as following aspects:(1)There are some characteristics as follows in construction project area: large thickness vadose, medium antifouling performance,aquifer moderately easy to pollution, more sensitive groundwater environment, large quantity of sewage emission in the project runtime, different kinds of pollutants, complicated sewage quality.(2) The level of the exploitation and utilization of unconfined water in asseeement area of evaluated is lower.There is no large centralized water supply source, except decentralized water for human and animal life in rural, groundwater is mainly used for agricultural arrigation. In the future, there is no planning of centrally development and utilization of groundwater resources in this area. The main environmental hydrogeological problem is underground water levels fall which caused by overdraft in asseeement area.(3)The result of environmental quality assessment of groundwater in rain season showed that in the selected 20 indexes,PH,total iron,volatile phenol,nitrite and fluoride generally exceeded Class Ⅲ water standard(the groundwater quality standard GB/T 14848-93). Sulfate and nitrate content in sample G02-B exceed Class Ⅲ water standard,as well as Mn content in sample K01-B and G05-B. It reflects that there has existed organic pollution in unconfined water already.(4) The result of groundwater environmental quality forecast evaluation for the sewage treatment plant showed that in the case of sudden accident, pollutants move faster in the vadose zone, and it need only 44.6 days infiltration into the underlying aquifer through the vadose zone. But after entering into the aquifer, the migration velocity of pollutants is very slow, it need about 11.5 years to reach Fengbu village which located in 585 meters in the downstream of it.