Soil Environmental Pollution Survey And Reuse Of Risk Assessment In The Industrial Sites

In this paper,the industrial site of soil heavy metal pollution is taken as the research object.Based on field investigation,document collection,and interviews with relevant personnel,the sources,pollution levels and pollutant concentrations of site pollution sources were analyzed.17 sampling points were set in the industrial site,and 51 samples were sampled at each sampling point according to the surface layer,middle layer and deep layer.Determination of Pb,Hg,Cr,Cu,Ni,Zn,As,Benzene and Carbon tetrachloride in soil,analyzed the pollution situation and concentration distribution of waste oil storage.Using different evaluation standards analysis industrial site pollution situation,research the pollutants concentration distribution of soil health risk assessment of oil depot and ecological risk assessment,so as to determine the future of this plot appropriate ways of recycling.Through the above research,draw the following conclusions:(1)The soil heavy metal pollution in the industrial site.According to the national soil environmental quality standard value(level Ⅱ),the average value of the single factor index of heavy metal elements in the soil of the oil reservoir was: Hg>Ni>Cr>1>Pb>Zn>As>Cu.Nemerow comprehensive pollution index ranking: S30>S21>S1>S25>S10>S48>S33>S51>S49>S34>S44>S6>S36>S45>S37> S8>S38.The nemero pollution index in the study area indicates that the soil heavy metal pollution level of the land is light pollution level,and the average pollution level is reached in some places.According to the land quality standards for exhibition sites(grade A)of the exhibition site,the average value of the single factor index was :Pb>1>Ni>Cr>Cu>As>Zn>Hg,only Pb exceeds the soil standard of the exhibition.The rate of benzene and carbon tetrachloride in samples was 86.2% and 92.2% respectively.Nemerow comprehensive pollution index ranking: S25>S21>S30>S34>S6 >S8>S48>S36>S38>S10>S37>S1 > S45>S33>S51>S49>S44>S38.The nemerow pollution index indicates that the study area indicates the level of light pollution of heavy metal pollution in this block.The average value of the single factor index of soil element background value in hefei area was:Cr>Pb>Hg>Cu>Ni>Zn>As>1.The soil elements in the study area exceeded the soil element background value in hefei area.The cumulative index was: Pb>Hg>Ni>1>Cr>Cu > Zn>As.To sum up,it can be seen that Pb,Hg,Cr、Ni、benzene and carbon tetrachloride in the soil of the oil reservoir is high.(2)Distribution characteristics of soil heavy metal pollutants in the industrial site.According to the data changes of Pb,Hg,Cr,Ni,Benzene and Carbon tetrachloride,the monitoring data of each pollutant in the sampling layer has certain volatility.Most point monitoring values decrease with the increase of depth,and the fluctuation may be caused by the artificial correction of local areas in the original production activities.The pollutants concentration distribution shows that Pb concentration in oil tank farm,Hg concentration distribution in the delivery platform and the junction with the diesel tank area,Ni concentration distribution in the gasoline tank farm,and Cr pollution in soil of the field distribution is more dispersed,benzene pollution is relatively concentrated in the surface soil,the petrol tank farm pollution distribution is more,carbon tetrachloride concentration of pollutants concentration in the gasoline tank farm and diesel oil tank farm.(3)Risk assessment of the industrial site.According to the use function of each region of the original oil reservoir,it is divided into four different regions and carries on the health risk assessment.The four areas are the diesel tank area and the gasoline tank area of the lubricating oil tank area.In the soil of the industrial site,the carcinogenic and non-carcinogenic risks of Ni、 benzene and Carbon tetrachloride in the sampling layer of the site are within acceptable range,so no site soil repair is required.The total ecological hazard index of the oil storage site decreases with the increase of soil depth,while the potential ecological harm of Hg is the largest,Pb is the second,and Cr and Ni are basically harmless.(4)The land reuse in the industrial site.Through the industrial site soil pollution investigation,status evaluation and distribution characteristics,the health risk assessment and ecological risk assessment can be concluded that the potential risk of soil in this plot is of medium risk level.The land is not suitable for crops such as dry land,water,fruit trees and vegetables.It can be used as woodland,landscaping,residence and general construction land.