Effective remediation of contaminated aquifer using groundwater circulation well(GCW)technology annot be achieved when the thickness of the aquifer is greater than 34.5 m.In this study,the simulation of GCW operation in a super-thick aquifer(STA)with a thickness of 80 m using MODFLOW and MODPATH was conducted to obtain the structure of GCW which is suitable for STAs.Simulation results demonstrate that a circulating zone was generated when the length of well walls section was≤26 m for two-screen GCW,with running period of 1 year and a flow rate of 400 m3·d-1.The maximum vertical length of circulating capture zone(27.5 m)was obtained from the repeated design studies,with the condition of 34 m-well length,two 4 m-long screen sections,one 26 m-long solid section,and a running period of 1 year.The remediation of STA with a thickness of 80 m was not accomplished using the optimized GCW with the maximum vertical length of circulating capture zone(27.5 m).However,multi-filter GCW significantly improved the remediation of STAs by increasing the range of remediation and reducing the ratio of dead zones.For a multi-filter GCW with three screens,the vertical length of the circulating capture zone of 56.52 m was achieved.Furthermore,a multi-filter GCW with four screens of 70.52 m was achieved with a particle recovery rate of 58％and a maximum influence radius of 44.95 m.Therefore,the multi-filter GCW with four screens can meet the requirements for remediating an 80 m-thick STA.These findings provide significant theoretical information for the design of GCW structures in STAs.
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