Pollution Degree And Health Risk Assessment Of Soil And Groundwater In An Electroplating Factory

The development of industry and people's improper environmental protection led to the gradual heavy metal pollution in China.The leakage of electroplating wastewater in an electroplating factory caused heavy metal contamination of the surrounding soil and groundwater,which poses a serious threat to the production,living and ecological environment of local residents.In this study,the electroplating plant was used as the research object,and the site was investigated.Single-index quality evaluation method,single-factor index evaluation method and Niemolu comprehensive pollution index method were used to evaluate the soil.Single-index evaluation method was used,and points were scored.The comprehensive assessment method and the control value Pki method of pollution index were used to evaluate the groundwater,and human health risk was evaluated from hazard identification,exposure assessment,toxicity assessment,and risk characterization.Then,Excel and the three-dimensional numerical model of groundwater were used.The scope of soil and groundwater pollution in contaminated sites was determined and the impact of various influencing factors on the migration of Cr6+was also analyzed,as well as the pathways,laws and influencing factors of Cr6+entering the human body.This provides a scientific basis for the rehabilitation and management methods of the contaminated sites in the later period and is conducive to protecting the health of the people working and living on the site.The main conclusions are as follows:?1?Assessment of soil and groundwater pollution:The soil pollution factor is Cr⁶⁺.From the plating bath in the contaminated site to the downstream southwest direction,which is the direction of surface runoff,the groundwater quality presents extremely heavy pollution-severe pollution-heavier pollution-medium pollution-Light pollution-uncontaminated distribution trends,pollution factors mainly Cr⁶⁺and Fe;?2?Health risk assessment of contaminated sites:The three soil sampling points in the contaminated sites and the groundwater health risk ratings of the monitoring wells in the site are all greater than the acceptable level of risk.The recommended target value for soil Cr⁶⁺remediation in contaminated sites is 25 mg/kg,and the target value of total Cr in soil is 250 mg/kg.The groundwater remediation recommended target value is Cr⁶⁺concentration 0.05mg/L.?3?Contamination range,migration rules and influencing factors of water and soil:soil pollution was distributed in a dotted pattern,with a total volume of approximately9169.8m³,a weight of approximately 18339.6t,approximately 45 kg of Cr⁶⁺,and soil pH and crevice development with Cr⁶⁺.The migration capacity in soil is proportional to the groundwater.The distribution of groundwater Cr⁶⁺contamination in the contaminated site is strip-like and distributed along the plating tank-SY022-SY021-SY016.The total area ofCr⁶⁺detected in groundwater is 4146m²,and the amount of contaminated groundwater is approximately 10082m³,using a three-dimensional numerical model of groundwater to characterize the migration of Cr⁶⁺to the southwest of the pollution source and the variation of the groundwater pollution scope in groundwater without human intervention.?4?The pathway,regularity and influencing factors of Cr⁶⁺entering the human body:Cr⁶⁺in the soil mainly enters the human body through respiratory inhalation of soil particles,skin contact,and oral entry into the human body;Cr⁶⁺in groundwater mainly through groundwater drinking and skin contact with groundwater Two ways to enter the human body.Cr⁶⁺enters the body mainly through drinking groundwater.