Saltwater intrusion into coastal aquifers has become a prominent environmental concern worldwide. As such, there is a need to prepare and implement proper remediation techniques with careful planning of freshwater withdrawal systems for controlling saltwater intrusion in coastal marine and estuarine environments. This paper investigates the performance of groundwater circulation well (GCW) in controlling saltwater intrusion problems in unconfined coastal aquifers. The GCWs have been established as a promising in-situ remedial technique of contaminated groundwater. The GCW system creates vertical circulation flow by extracting groundwater from an aquifer through a screen in a single well and injecting back into the aquifer through another screen. The circulation flow induced by GCW force water in a circular pattern between abstraction and recharge screens and can be as a hydraulic barrier for controlling saltwater intrusion problem in coastal aquifers. In this study, an effort has been made to investigate the behavior of saltwater intrusion dynamics under a GCW. An experiment has been conducted in a laboratory-scale flow tank model under constant water head boundary conditions, and the variable-density flow and transport model FEMWATER is used to simulate the flow and transport processes for the experimental setup. The evaluation of the results indicates that there is no further movement of saltwater intrusion wedge towards the inland side upon implementation of GCW, and the GCW acts as a hydraulic barrier in controlling saltwater intrusion in coastal aquifers. The present study reveals the GCWs system can effectively mitigate the saltwater intrusion problem in coastal regions and could be considered as one of the most efficient management strategies for controlling the problem.

盐水侵入沿海含水层已成为全球关注的重要环境问题。因此，需要准备和实施适当的补救技术，并仔细计划淡水抽取系统，以控制沿海海洋和河口环境中的咸水入侵。本文研究了地下水循环井（GCW）在控制无限制沿海含水层中的盐水入侵问题方面的性能。GCW已被确立为一种有前途的被污染地下水原位修复技术。GCW系统通过在单口井中通过滤网从含水层中抽取地下水，然后通过另一个滤网注入含水层中来产生垂直循环流。GCW引起的循环流迫使水在取水和补给滤网之间呈圆形分布，并且可以作为控制沿海含水层中海水入侵问题的水力屏障。在这项研究中，已努力研究GCW下盐水入侵动力学的行为。在恒定水头边界条件下，在实验室规模的水箱模型中进行了实验，并使用可变密度的水流和运输模型FEMWATER模拟了实验装置的水流和运输过程。结果评估表明，实施GCW后，盐水入侵楔形物不会进一步向内陆移动，并且GCW充当控制沿海含水层中盐水入侵的水力屏障。