Monitoring of dynamic groundwater level change by ground penetrating radar for quantitattive estinmation of hydraulic parameters

Abstract

In order to accurately monitor the dynamic groundwater level change caused by the well pumping in a non-destructive way, we developed Common Mid-Point (CMP) method using Ground Penetrating Radar (GPR). The envelope velocity spectrum and an automatic velocity picking scheme were proposed for the accurate velocity analysis of CMP dataset. We applied the algorithm to the GPR data acquired near Tuul river in Mongolia. The obtained vertical velocity profile was converted to the vertical water content profile, in which the groundwater level could be easily identified. In this measurement, a groundwater level rise of 0.21 m was observed after the pumping was stopped. The dynamic groundwater level change estimated by GPR was used to estimate the hydraulic conductivity of the unconfined groundwater aquifer. The result agreed well with a previous study.