基于全周期场地概念模型的场地环境精准调查应用案例

全周期场地概念模型可以尽可能准确地表征场地实际污染空间分布和赋存状态，有效支撑后期场地精准修复或风险管控工作.本文以京津冀地区某氯代烃污染场地为研究对象，在污染识别、场地初步调查、详细调查和补充调查各阶段分别构建针对性的场地概念模型.采用薄膜界面探测器和高密度电阻率法等现场快速筛查设备的应用，辅助确定了潜在污染源和重点调查区域；同时针对部分位置大量检出氯代有机物代谢产物氯乙烯，判断该场已经发生较为明显的污染物生物降解现象.通过选取典型钻孔和剖面进行降解指示性产物和组分图谱分析，并结合地下水中氯代烃厌氧生物降解潜力综合评分达到22分的结果，判断该场地具有较强的厌氧生物降解能力.这种逐级优化形成针对场地污染调查的全周期场地概念模型，为精准地掌握该场地实际污染情况提供了良好的工作基础和科学支撑.

Application Case of Accurate Site Investigation with Life-Cycle Conceptual Site Model Development

A life cycle conceptual site model (LC-CSM) can represent the actual spatial distribution and migration of pollution of a site very accurately and be beneficial in supporting decisions for accurate site remediation or risk management. A volatile chlorinated hydrocarbon contaminated site in the Beijing-Tianjin-Hebei region was chosen as the study case. LC-CSMs were established following the site assessment, preliminary investigation, detailed investigation, and supplementary investigation of each stage. The application of field screening tests such as a membrane interface probe and the multi-electrode resistivity method assisted in identifying potential pollution sources and hot points. Concurrently, a large amount of vinyl chloride, the end product of chlorinated hydrocarbon degradation, was detected in some boreholes, indicating that pollutant biodegradation had occurred at this site. Some typical boreholes and cross-sections were chosen to analyze the biodegradation indicators and chemical fingerprints, combining the results of the comprehensive score of chlorinated hydrocarbon anaerobic biodegradability in groundwater reaching 22. It is judged that the site has strong anaerobic biodegradability. This step-by-step optimization forms an LC-CSM for site investigation, which provides scientific support for accurate site characterization.