A GENERAL FRAMEWORK FOR SITE SELECTION AND OPERATION EVALUATION OF THE AQUIFER STORAGE AND RECOVERY

Land subsidence due to groundwater overdraft is an urgent environmental problem in Choushui river alluvial fan in Taiwan. Aquifer storage and recovery (ASR), where excess surface water is injected into subsurface aquifers for later recovery, is one promising strategy for managing surplus water and may overcome water shortages. The performance of an ASR scheme is generally evaluated in terms of recovery efficiency, which is defined as percentage of water injected in to a system in an ASR site that fulfills the targeted water quality criterion. Site selection of an ASR scheme typically faces great challenges, due to the spatial variability of groundwater quality and hydrogeological condition. This study target to propose a novel framework for the ASR site selection and operation evaluation. The site selection is based on groundwater quality and aquifer transmissivity. After determining the potential ASR site, a simplified axisymmetrical radial advective-dispersive transport model is used toevaluate the recovery efficiency based on the concentration breakthrough curves of concerned contaminants at the ASR well. The results of this study may provide government administrator for establishing preliminary ASR scheme.