Field experiments were carried out in a cavity type of Aquifer Storage Recovery well installed in an aquifer having highly saline native groundwater (EC = 28.4 dS m-1). Good quality canal water (EC = 0.46 dS m-1) was injected to investigate the effect of buffer storage volume (varying from 2000 –14000 m3) and storage time (varying from 2.5–70 days) on the recovery efficiency in five ASR test cycles. Field experiments with different ASR cycles showed that the recovery efficiency increased with increasing buffer storage volume and decreased with increasing storage time. For buffer storage volume of 14000 m3 and storage time of 13 days the observed instantaneous recovery efficiency IRE and integrated recovery efficiency CRE at the target water quality of 2 dS m-1 of the recovered was 80.2 and 108 % respectively. At the test site, it was observed that a buffer storage volume of 14000 m3 is sufficient to achieve a recovery efficiency of 70 % for a storage time of two months. The results obtained in this study suggests that the ASR technique has considerable potential to improve the quality of groundwater in different parts of Haryana State characterized by inland drainage basin conditions and poor groundwater quality. An analytical model described successfully the prediction of fraction of injected water in the recovered water f (t) versus I (t) data up to I = 0.6. Longitudinal dispersivity decreased with buffer storage volume. Thereby suggests reduced levels of mixing between native and injected water with increased levels of buffer storage volume.
Key words: ASR cavity well, recovery efficiency, buffer storage volume, storage time, dispersivity and analytical modeling