Health-based Risk Evaluation Of The Reusing Industrial Land In A Mining Zone

At present,environmental pollution incidents occurred frequently in industrially used areas,which not only destroys the ecological environment,also harms the people’s health and security.Facing the severe situation,the assessment of health,environmental remedy and treatment have become a vital part in environmental management in our country.Domestic scholars have also conducted a large number of researches on the human health risk assessment,but the research under the background of mines is relatively less.This study selected the left land as the research object,analyzing the enterprise activities and possible environmental issues in the used areas,and making the evaluation of possible environmental risk in the process,at the same time,including the influence of mining environment on human health.Specifically,there are 27 soil sampling points and 54 soil samples were collected(including 10 samples of control point);3 groundwater monitoring wells,from which 3 groundwater samples were collected.Among them,42 soil samples(including 10 samples of control point)are used for detecting heavy metals,and 46 samples are used to detect organics;Groundwater samples are used to test pH value,heavy metals and organic matter,and then make a contrast between the test data and risk control filter value.Finally,an assessment on arsenic and lead in soil will be formed and guidance will be provided on the basis of the assessment.Main conclusions are as follows:1)the groundwater is neutral,not detecting the organic pollutants,heavy metals meet the groundwater quality evaluation standard "(GB/T 14848-93)Ⅳ water quality standard,block groundwater environment is not polluted by the former enterprise,at the same time,mining environment is not harmful to groundwater environment.And the test data of organics is below filter values.The test data of arsenic and lead in soil samples is beyond filter values.The raw materials,production processes and products in the areas are not involved in heavy metal.The reason is that the area is located in the mountain which belongs to copper lead polymetallic zone and in which arsenic and lead are high.Although no environmental pollution was caused,under the influence of the original mining area environment,the test data of arsenic and heavy metals in some soil samples are beyond the risk control filter value,1.138-1.408-4.875 times and 0.508 times.It is harmful to human health,so it is necessary that we should make an assessment on health before reusing the area.2)The results of the risk evaluation show that the risk of cancer due to arsenic pollution in soil and the non carcinogenic risk were both higher than the acceptable level of risk.The value-at-risk of arsenic is 556.5 mg/kg.Research uses USA EPA and the health risk assessment model recommended by the center for disease control and prevention of adult blood lead to infer the risk controlling values.And after revising the data,the lead risk control value is 481.8 mg/kg.Ultimately,with comprehensive consideration about the background,the unpolluted area and the actual conditions of soil and groundwater environment,this study suggested that we should set the controlling values of arsenic and lead as the target values at the risk relatively.3)Based on the purpose of protecting human health,considering the influence of the mining area environment,research suggests that the exposure of exceeding soil heavy metal should be controlled in an isolate way,and we should strengthen the supervision and management during the later reusing.Or use the stabilized chemical remediation technology to do some repair and restoration and they can also be used in a reasonable way.After calculating,the area where arsenic is high is about 5367 m2,and the soil volume for remedying is about 2683.5 m3;the area where lead id high is about 12164 m2,and the soil volume for it is about 18239 m3.