上海市浅层地下水在线监测技术要点

地下水在线监测技术可以实现地下水水质的高频监测,是未来发展的重要趋势。梳理国内外地下水在线监测技术研究进展,以上海市典型水文地质特征与环境质量状况为例,探讨地下水在线监测点位布设、指标筛选、监测方式及监测井设计等技术要点。首先,优化监测点位布设,对需要开展高频监测的区域或重点风险源开展在线监测,以代表性点位反映总体地下水环境质量状况。其次,综合筛选监测指标,除常规参数外,优先选取水体中的氨氮、高锰酸盐指数等作为在线监测指标,在具有潜在有机污染的区域,选取水中有机物、水中油等作为有机污染指示性指标。应进一步加强指标之间的相关性分析,为指示性指标的确立提供依据。再次,合理确定监测方式,根据取样方式以及污染源风险等级,设置相应的微型站和小型站。最后,优化监测井设计技术方案,进一步研究不同井管材质对地下水中无机或有机污染物的长期吸附(解吸)作用。

Discussion on Key Technical Points of On-line Monitoring of Shallow Groundwater in Shanghai

Groundwater on-line monitoring technology can realize high frequency monitoring of groundwater quality,which is an important trend in the future.This paper reviews the research progress of groundwater online monitoring technology at home and abroad,takes the typical hydrogeological characteristics and environmental quality situation of Shanghai as an example,and discusses the technical key points such as point layout,index screening,monitoring method selection and monitoring well design.Firstly,the layout of monitoring points is optimized.It is advisable to carry out online monitoring for the regions or key risk sources that need to be monitored with high frequency,so as to reflect the overall groundwater environmental quality with representative points.Secondly,comprehensive screening of monitoring indicators.In addition to conventional parameters,pollutants of concern in water,such as ammonia nitrogen and permanganate index,are selected as online monitoring indicators.In areas with potential organic pollution,organic matter and oil in water are selected as indicators of organic pollution.The correlation analysis between indicators should be further strengthened to provide a basis for the establishment of indicative indicators.Then,the monitoring method is reasonably determined.According to the sampling method and the risk level of the pollution source,the corresponding mini-stations and mini-stations can be set up.Finally,the technical scheme of monitoring well design is optimized to strengthen the study on the long-term adsorption/resolution of inorganic or organic pollutants in groundwater by different well pipe materials.