Using BGPR to monitor water content during a pumping test

• Main Author: Glinski, Gerd Karl-Hans von
• Other Authors: Ferre, Ty P. A.
• Language: en_US
• Published: The University of Arizona. 2004
• Online Access: http://hdl.handle.net/10150/626833; http://arizona.openrepository.com/arizona/handle/10150/626833

Two 3-day pumping tests were performed in the riparian zone alongside a perennial stretch of the San Pedro River located in southern Arizona, in 2001. A shallow unconfined aquifer was pumped with three fully penetrating wells. Our purposes were to determine whether borehole ground penetrating radar (BGPR) can be used to monitor transient flow in the vadose zone with high spatial and temporal resolution and to determine if these data could be used to advance our understanding of vadose zone flow processes. BGPR measured a dramatic change of water storage in the unsaturated zone during the tests. The ratio of the cumulative storage loss to the drawdown defined instantaneous specific yield. There was an initial period of delayed drainage as the instantaneous specific yield slowly increased to equal the laboratory-derived value. The BGPR measured water content profiles determined effective hydraulic parameters in calibrating a one-dimensional vertical unsaturated flow model.