湖北某重金属污染土壤稳定化/固化治理工程实例

Case Project of Solidification/Stabilization of Heavy Metal Contaminated Soils in Hubei Province

为保证南水北调水源地水质安全,该项工程对湖北省郧县境内4个关停搬迁企业原址约16万m3重金属污染土壤进行了修复治理。污染土壤清挖标准为《展览会用地土壤环境质量标准》(HJ350—2007)A级标准,污染土壤无害化处理验收标准为浸出液浓度低于《地表水环境质量标准》(GB3838—2002)中IV类水体标准值。工程采用异位稳定化/固化技术对重金属污染土壤进行了无害化处理,所用稳定化/固化药剂为施工单位自主研发的硫系和铁系稳定化药剂;无害化处理后的近20万m3土壤采用安全填埋进行处置。工程的成功实施为南水北调库区水质安全提供了有力保障。

In order to ensure the quality and safety of the water sources along the central route of South-to-North Water Diversion Project, about 160 thousand cubic meters of heavy metal contaminated soils were remediated at the former locations of 4 shut-down and relocated enterprises within Yun County in Hubei Province. The standard for polluted soil cleanup accorded with level A regulated in the Standard of Soil Quality Assessment for Exhibition Sites （HJ350-2007）. With regard to the standard for check and acceptance of environment-friendly treatment of polluted soils, leaching concentrations of heavy metals and pH in the contaminated soil after remediation accorded with level IV standard value regulated in the Environmental Quality Standard for Surface Water （GB3838-2002）. In the engineering project, ex-situ solidification/stabilization technology was adopted to remediate the contaminated soils in a harmless way by use of the sulphur-based and iron-based solidification/stabilization reagents independently developed by the construction company itself. After the remediation, about 200 thousand cubic meters of soils were disposed by safe landfill. Successful implementation of this engineering project provided an important guarantee for the water quality and safety of the reservoir areas of the South-to-North Water Diversion Project.