Beijing Key Laboratory of Water Resources and Environmental Engineering, School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, China.
Sci Total Environ. 2012 Aug 15;432:216-26. doi: 10.1016/j.scitotenv.2012.06.005. Epub 2012 Jun 28.
Groundwater contamination risk assessment is an effective tool for groundwater management. Most existing risk assessment methods only consider the basic contamination process based upon evaluations of hazards and aquifer vulnerability. In view of groundwater exploitation potentiality, including the value of contamination-threatened groundwater could provide relatively objective and targeted results to aid in decision making. This study describes a groundwater contamination risk assessment method that integrates hazards, intrinsic vulnerability and groundwater value. The hazard harmfulness was evaluated by quantifying contaminant properties and infiltrating contaminant load, the intrinsic aquifer vulnerability was evaluated using a modified DRASTIC model and the groundwater value was evaluated based on groundwater quality and aquifer storage. Two groundwater contamination risk maps were produced by combining the above factors: a basic risk map and a value-weighted risk map. The basic risk map was produced by overlaying the hazard map and the intrinsic vulnerability map. The value-weighted risk map was produced by overlaying the basic risk map and the groundwater value map. Relevant validation was completed by contaminant distributions and site investigation. Using Beijing Plain, China, as an example, thematic maps of the three factors and the two risks were generated. The thematic maps suggested that landfills, gas stations and oil depots, and industrial areas were the most harmful potential contamination sources. The western and northern parts of the plain were the most vulnerable areas and had the highest groundwater value. Additionally, both the basic and value-weighted risk classes in the western and northern parts of the plain were the highest, indicating that these regions should deserve the priority of concern. Thematic maps should be updated regularly because of the dynamic characteristics of hazards. Subjectivity and validation means in assessing the vulnerability result were also discussed. In addition, GIS technology was essential in completing the assessment work.
地下水污染风险评估是地下水管理的有效工具。大多数现有的风险评估方法仅考虑基于危害和含水层脆弱性评估的基本污染过程。考虑到地下水开采潜力，包括受污染威胁的地下水的价值，可以提供相对客观和有针对性的结果，以辅助决策。本研究描述了一种将危害、固有脆弱性和地下水价值综合起来的地下水污染风险评估方法。危害的危害性通过量化污染物特性和渗透污染物负荷来评估，固有含水层脆弱性使用改进的 DRASTIC 模型进行评估，地下水价值基于地下水质量和含水层储存量进行评估。通过组合上述因素生成了两个地下水污染风险图：基本风险图和价值加权风险图。基本风险图通过叠加危害图和固有脆弱性图生成。价值加权风险图通过叠加基本风险图和地下水价值图生成。通过污染物分布和现场调查完成了相关验证。以中国北京平原为例，生成了这三个因素和两个风险的专题地图。专题地图表明，垃圾填埋场、加油站和油库以及工业区是最具危害性的潜在污染来源。平原的西部和北部是最脆弱的地区，具有最高的地下水价值。此外，平原西部和北部的基本风险和价值加权风险等级都最高，表明这些地区应该优先关注。由于危害具有动态特征，专题地图应定期更新。还讨论了评估脆弱性结果的主观性和验证手段。此外，GIS 技术对于完成评估工作至关重要。
