Practical Research On Investigation And Risk Assessment Of A Coking Site

This article took the site left by a coking plant in a foreign-invested plant as the research object,after on-site investigation,survey and sample collection and collected samples are tested to obtain the actual site environmental pollution value.Compared Chinese and US standards(HJ25.3-2014,GB 36600-2018,US General Soil Screening Benchmarks,etc.),used stricter benchmarks for site risk assessment and remediation target research,and provided environmental pre-investigation and decision-making layer for enterprises before investment provide reference data.The research results were as follows:1.After on-site exploration,there were organic matter infiltration in the residual areas of some workshops,such as the first recycling plant and the tar plant.2.According to on-site sampling,tested samples and analyzed the results.Benzene series,polycyclic aromatic hydrocarbons,and heterocyclic aromatic hydrocarbons polluted the surface soil in the site through atmospheric diffusion.Polycyclic aromatic hydrocarbons were more polluted.The benzene series were less polluted in the surface soil and deep soil.Compared with other related studies,the surface area of polycyclic aromatic hydrocarbons polluted is wider,and the middle area of benzene series polluted is wider.3.Analysis of solute transport model showed that the migration of pollutants in groundwater is relatively slow.In 10 years,the pollution distance of naphthalene in the direction of water flow was about 100 meters,and that of benzene was 150 meters,and the lateral migration distance was smaller.4.The Pro-UCL model was used to calculate the 95% confidence upper limit concentration of the pollutants,and the toxic effects of the pollutants were derived from the reference dose and the linear model respectively.It was found that benzo(g,h,I)pyrene is a non-carcinogenic substance,and other pollutants are carcinogenic substances.5.Carried out a risk assessment of the pollutants.The arsenic had a carcinogenic risk,but the carcinogenic risk was within the acceptable range.Both polycyclic aromatic hydrocarbons and benzene series exceeded the acceptable carcinogenic risk value.6.The restoration target calculated by the RCBA model and determined by the EMSOFT model correction: the surface layer of benzo(a)anthracene is 2.4mg/kg,benzo(a)pyrene is 0.24mg/kg,indeno(1,2,3-cd)Pyrene is 2.4mg/kg,the second and third layers: benzene is 19mg/kg.The repair site is located in the remnants of the first recycling plant,the second recycling plant,the tar branch plant,the gas purification plant,the refined benzene plant.In summary,the key values of the polluted site survey and health risk assessment results were compared with Sino-US soil screening standards,and a more stringent US benchmark was selected for evaluation,as reference data for enterprise project site remediation and decision-making.The thesis can also provide pollutant characteristic parameters for similar contaminated sites,and provide practical suggestions for guiding the selection and treatment of soil treatment technologies.