某矿业企业遗留重金属污染场地污染调查与风险评估

以某矿业企业搬迁遗留场地为研究区域,根据《场地环境调查技术导则》(HJ 25.1-2014)、《污染场地风险评估技术导则》(HJ 25.3-2014)、《土壤环境质量建设用地土壤污染风险管控标准(试行)》(GB 36600-2018)、《重金属污染场地土壤修复标准》(DB43/T 1125-2016)等进行场地环境调查和风险评估。结果表明,敏感用地条件下,场地的关注污染物锌、铅、镉、砷危害商超过1,镉、砷致癌风险值超过10^-6,超过《污染场地风险评估技术导则》(HJ 25.3-2014)中可接受风险水平,场地存在健康风险,须进行修复后才能开发利用。经计算确定本场地修复目标值为铅400 mg/kg、镉20 mg/kg、锌1 323 mg/kg、砷20 mg/kg。场地重金属总污染面积约为10 056 m^2,总污染土方量约为14 677.6 m^3。

Pollution Investigation and Risk Assessment of the Site Contaminated by Heavy Metals from a Mining Enterprise

The environmental site investigation and health risk assessment were performed for the remaining site of a mining enterprise according to"Technical Guidelines for Environment Site Investigation"(HJ 25.1-2014),"Technical guidelines for risk assessment of contaminated sites"(HJ 25.3-2014),"Soil environmental quality-Risk control standard for soil contamination of development land"(GB 36600-2018),"Standards for Soil Remediation of Heavy Metal Contaminated Sites standard"(DB 43/T 1125-2016).The results showed that under sensitive land conditions,the risk of zinc,lead,cadmium and arsenic in the site was more than 1,and the carcinogenic risk value of cadmium and arsenic was more than 10-6.Exceed the acceptable risk level in the"Technical guidelines for risk assessment of contaminated sites"(HJ 25.3-2014),there are health risks in the site,which should be repaired before development and utilization.After calculation,the target value of this site is determined to be 400 mg/kg lead,20 mg/kg cadmium,1323 mg/kg zinc and 20 mg/kg arsenic.The total heavy metal pollution area of the site is about 10056 m2,and the total polluted earth volume is about 14677.6 m3.