基于特定场地的挥发/半挥发有机化合物(VOC/SVOC)空间分布与修复边界确定

Site-specific spatial distribution of VOC/SVOC and determination of the remediation boundary

选择我国某典型的废弃化工污染场地为研究对象,在对场地全面调查的基础上,采用美国试验与材料学会(ASTM)规范的场地环境评价方法,对场地中污染物类型、污染程度和空间分布进行了描述.同时,以人体健康风险为基础对场地修复目标进行推算,并界定修复边界和测算污染土壤体积.结果表明,四氯化碳、四氯乙烯、五氯乙烷、六氯丁二烯、六氯乙烷和六氯苯等挥发/半挥发性有机化合物为场地土壤中的主要污染物类型,其含量超过我国现有标准.根据场地特性,以最大可接受风险水平1×10-4、1×10-5和1×10-6计算得出的修复目标值界定修复边界,场地中对应区域的污染土壤体积分别为20457、25600和37300m3.最后,根据综合场地利用规划和成本投入要求,对场地中污染土壤分类处理和修复提出了技术建议.

Types, extents and spatial distributions of contaminants in a typical abandoned industry site were analyzed based on full field investigation according to the site assessment procedure proposed by ASTM. The target level of remediation was determined based on the maximum acceptable environmental health risks. The boundary and total volume of contaminated soil in this site were defined. Results indicated that the contents of carbon tetrachloride, tetrachloroethylene, pentachloroethane, hexachlorobutadiene, hexachloroethane and hexachlorobenzene in the soil exceeded the national standard. According to the target value derived from the acceptable risk level of 1×10^-4,1×10^-5,1×10^-6 and site characteristics, the total volume of contaminated soils with different risks was 20457, 25600 and 37300 m^3 respectively. Treatment and remediation technologies were proposed in view of cost efficiency and future land development.