Study On Site Environmental Risk Assessment And Restoration Scheme Of The Original Chemical ConcentrationArea In Jiangyan Development Zone

Since the national "Soil Ten" document was issued,the site restoration work of our country has entered a new stage;many places have carried out site pollution restoration work.With the continuous increase of the state’s environmental protection efforts and the optimization and adjustment of the industrial structure,some chemical enterprises have been closed or relocated,and the remaining site pollution problems need to be solved urgently,the rehabilitation of the former chemical production site becomes a prerequisite for the continued use of the original site.Due to the complexity of chemical products,different chemical enterprises have different characteristics of site pollution,resulting in different environmental risks;the site restoration technology used is also different.The former chemical concentration area of Jiangyan District development zone in Jiangsu Province is one of the key areas for site restoration in China.In this paper,the site of Jiangyan District Chemical Fertilizer Co.,Ltd.located in the former chemical concentration area of Jiangyan District development zone was taken as the research object and the site environmental risk assessment was carried out to study the suitable restoration technology and restoration scheme.The main findings and contents are as follows:(1)to select the main pollutants and their ranges of environmental pollution through scientific formulation of the Environmental Monitoring Plan for the polluted sites.In practice,a total of 954 soil samples were tested at 215 sites in the former Jiangyan District chemical fertilizer Co......Among them,5 soil samples at 3 sites exceeded the standard of Petroleum Hydrocarbon,and 10 soil samples at 9 sites exceeded the standard of Benzopyrene.The exceeding limit of Petroleum Hydrocarbon is 3.6 times,and the exceeding limit of Benzopyrene is 4.9 times.It is finally confirmed that the characteristic pollutants concerned in the plot are petroleum hydrocarbons and benzopyrene.(2)Adopting standard environmental risk assessment technology,it has been proved that the two pollutants,petroleum hydrocarbon and Benzo(a)Pyrene,are harmful to human health.According to Data Analysis and field investigation,there are 13 contaminated blocks in the Former Jiangyan District Chemical Fertilizer Co.,Ltd....The area of soil to be repaired is 5,794.47 square meters,and the amount of earth to be repaired is 12,212.28 cubic meters.(3)From the point of view of technical and economic comparison,this paper puts forward the evaluation method for the comparison and selection of the site restoration alternatives.Based on 18 indexes and weights,the techniques of heterotopic stabilization,risk management(physical barrier)and soil leaching were compared;suggest the use of heterotopic solidification/stabilization remediation technology for contaminated land in Jiangyan District,Taizhou.(4)In view of the correlation and similarity in product structure,production process and pollutant emission between the remaining closed and relocated enterprises in the original chemical concentration area of Jiangyan Development Zone and the original Taizhou Jiangyan chemical fertilizer Co.,Ltd.,the restoration scheme generated in this study can be used as one of the comparison schemes for the restoration of the remaining plots in the original chemical concentration area of Jiangyan development zone.