The Study On Optimization Of Groundwater Monitoring Station Network Of Alluvial-proluvial Fan In Chao Bai River,Beijing

Groundwater is an indispensable resource in the process of social and economic development.In recent years,a series of environmental geological problems such as a drop in groundwater level,an expansion of landing funnel,and land subsidence have emerged due to unreasonable exploitation which exposing some problems in groundwater monitoring.For example,if the monitoring of groundwater dynamic changes is not timely and the monitoring data are representative,etc.,the above problems cannot be dealt with in time.How to deploy groundwater monitoring wells to obtain maximum groundwater information within a certain range of economic capabilities and serve for groundwater management decision-making and scientific research is the main content of this study.In this study,the Chaobai River Alluvial-diluvial fan was selected as the research area.The Chaobai River alluvial-diluvial fan,as the administrative sub-center of Beijing and one of the major water sources in Beijing,played a crucial role in solving the water supply in Beijing.Optimizing the existing groundwater monitoring station network to obtain accurate groundwater monitoring information can provide policy makers with scientific and reasonable groundwater management policies to mitigate a series of environmental geological problems brought about by changes in the groundwater level,and in addition to groundwater resource level water in the study area.Dual-control management is also of great significance.Based on the analysis of the hydrogeological conditions in the study area and the analysis of the existing groundwater monitoring station network,this paper carried out the optimization design of the groundwater monitoring station network by using the hydrogeological analysis method and the ordinary Kriging method.Finally,51 dynamic aquifers for shallow aquifers and 17 dynamic aquifers for deep aquifers were identified and the shallow and deep aquifer variograms were determined.The optimized shallow groundwater monitoring wells were reduced from 67 to 55 eyes,and the deep groundwater monitoring wells were reduced from 44 to 35 eyes.The overall layout of the monitoring station network was more reasonable and representative.Through the time series analysis of groundwater dynamic monitoring data in typical boreholes,the trend of the water level sequence,periodic fluctuations and random terms are studied.The frequency of water level monitoring that satisfies the detection trend and periodic fluctuations is determined to be 9 times a year and 10 times a year respectively.In the end,it is believed that the monthly monitoring frequency can meet the requirements for monitoring and management of regional groundwater dynamic changes,and determining the monthly groundwater level data selection can satisfy the study of regional groundwater dynamic changes.