Study On Environmental Impact Assessment Of Groundwater In Reconstruction Project Of Yantai Bajiao Power Plant Units

In the research process on the groundwater environment evaluation of Yantai Bajiao power plant units,we need to predict and evaluate the directly and indirect damage,and put forward the prevention measures for the influence and damage,provide scientific basis for the construction project site selection,engineering design and environmental management.Based on the project overview,the specific situation of groundwater pollution sources and groundwater environmental quality evaluation,the mathematical model and conceptual model of groundwater flow was established.After the parameter identification and model test,this paper simulated analysis of the groundwater flow system evaluation area,and a Simulation of solute transport in groundwater was carried out by using the GMS software based on finite difference method.The main conclusions as follows:1)The antifouling performance of the aeration zone in the proposed project is medium,and the fouling resistance of the vadose zone in the ash field is weak.The pollution characteristics of the aquifer in the plant and the ash field are both easy to classify,and the sensitivity of groundwater is not sensitive.The amount of sewage produced in the plant is classified as middle;the storage mode of ash yard is dry ash storage,and the amount of sewage generated is classified as small.The emission of pollutants may be discharged for pH,iron,fluoride and sulfate acid wastewater containing a small amount of heavy metals,water quality classification complexity is moderate;water quality index of ash field needed to forecast for PH,SO42-,F-,total hardness 4,both conventional pollutants,water quality classification complexity is simple.The construction project is a category I project,and the groundwater environmental impact assessment grade is two.2)From the current situation of evaluation,the exceed the groundwater standard index mostly are NO3-and NH4+ in wet period and dry period;In the investigation area,NO3-,total hardness and salinity exceeded the standard of groundwater,and in the investigation scope of ash field exceeded standard item is NO3-.The main reason of Fe3+,Cl-,Mn,total hardness,degree of mineralization is the evaluation area exceed the standard aquifer of fine particles,runoff conditions,chemical enrichment caused by distributed surface;exceed the standard evaluation area of NO3-,NH4+ and NO2-,mainly affected by domestic sewage,fertilizer and other agricultural activities may also be at the same time have a certain effect.3)The groundwater environmental impacts of 5 kinds of credible accidents during the operation of the project are simulated and evaluated,predict the scope of diffusion of pollutants under different simulated conditions,the degree of impact and the average concentration of pollutants in groundwater and exceeding the standard.4)Be directed against the the project adversely affect the groundwater,the Countermeas--ues of prevention and control of pollution and the Countermeasures of environmental manag--ement have been clarified,advised to establish a partition anti-seepage leak detection system,...