Numerical Simulation Of Groundwater In North Water Source (Water Source) Of Zhangjiakou City

Beishuiyuan water source is the oldest water source in Zhangjiakou In recent years,with the expansion of the city scale and the population growth,the original water supply source has been unable to meet the mining and industrial water requirements.Therefore,this paper takes the water source of the north water source of Zhangjiakou City as the research area,evaluate the amount of groundwater resources,effectively solve the problem of local residents'production and living water,and ensure the healthy development of the ecological environment.This paper is based on the results of hydrogeological survey of Zhangjiakou City Beishuiyuan reconstruction project.Through collecting and finishing hydrogeological drilling data in the study area.The 3D visualization modeling software of GMS is used to establish a3D geological structure visualization model for water source,which can visually display the3D geological structure of the study area from multiple directions.Based on the identification of the geological background and hydrogeological feature of the study area,the hydrogeological conceptual model of the north water source of Zhangjiakou City was established.The hydrogeological parameters are initially determined based on the measured pumping test data and groundwater dynamic data.The model is identified and verified by using the water level dynamic data and the model to calculate the fitting degree as the calibration standard.And inverted the hydrogeological parameters of the study area.The results show that the model calculation results are well fitted to the measured data in the study area,indicating that the established model can reflect the actual hydrogeological conditions in the study area,can be used for groundwater level prediction.By means of equalization method and numerical simulation,it is determined that the groundwater recharge resource is 557.02×10~4m~3/a under the current conditions of the study area,the groundwater storage resource is 9.048m~3/a,and the allowable groundwater exploitation is 557.03×10~4m~3/a.The water supply in the study area meets the development needs of the planned 10,000 m~3/d production volume,and the mining does not exceed the allowable range.In the future planning period,the groundwater level deepening process of the water source will be stable,and there will be no large-scale water level dropping funnel.Taking the water level in January 2018 as the initial flow field,three scenarios are used to predict the water level in the study area under the condition of a precipitation guarantee rate of 95%:(1)The model is operated at a mining capacity of 10000 m~3/d.After one year,the average depth in the area is 0.1 m,and the maximum depth of the falling funnel center is 2.5m.After five years,the average depth in the area is 0.3 m,and the maximum depth of the falling funnel center is 2.7 m.Ten years later,the groundwater flow field did not change significantly,and the groundwater level reached a new dynamic balance.(2)The model is operated at a mining capacity of 12000 m~3/d.After one year,the average depth in the area is0.2 m,and the maximum depth of the falling funnel center is 2.6 m.After five years,the average depth in the area is 0.4 m,and the maximum depth of the falling funnel center is 3 m.Ten years later,the average depth in the area is 0.6 m,and the maximum depth of the falling funnel center is 3.2 m.(3)The model is operated at a mining capacity of 10000 m~3/d.After one year,the average depth in the area is 0.4 m,and the maximum depth of the falling funnel center is 3 m.After five years,the average depth in the area is 0.7 m,and the maximum depth of the falling funnel center is 3.3 m.Ten years later,the average depth in the area is 1 m,and the maximum depth of the falling funnel center is 3.5 m.