Pumping test is commonly used in estimating aquifer properties such as hydraulic conductivity (KH), anisotropy (KH/KV), specific yield (Sy), and specific storage (Ss). Analytical solutions with curve fitting software, such as AQTSOLVE, are used for matching the observed drawdown curves in one or several observation wells including the records in the pumping well. These analytical solutions often simplified the natural site conditions by making various assumptions on initial and boundary conditions. The objective of this study is to estimate the effect of these simplified assumptions on estimated aquifer properties. The study used the pumping test records collected in Muscat International Airport premises. They include drawdown recorded in the pumping well (PW-8) and in two monitoring wells (MW-19 and MW-20) located 10 m and 40 m away from the pumping well. The pumping test was conducted for 24 hours with a constant pumping rate of 10.04 L/s. The drawdown curves also included records from the recovery test, which was started immediately after the pumping test was stopped and lasted for 12 more hours. Neuman (1975) and Moench (1997) solutions were used with AQTSOLVE software to obtain a unique set of aquifer properties. These analytical solutions were however unable to include the effect of the aerial recharge and the initial hydraulic gradient. Therefore, MODFLOW numerical model was used to constrain the parameters considering all possible initial and boundary conditions. The three-dimensional groundwater flow model was calibrated and verified by using observed drawdown records in steady and transient states. Both, auto-calibration and trial and error techniques were used for constraining the parameters. Uncertainty analysis was conducted to understand the effects of pumping rate and the constant head boundary on hydraulic conductivity estimations and hydraulic head variations. Furthermore, a sensitivity analysis was conducted to understand the significance of aquifer properties in regulating groundwater flow in the study area. The estimated parameters when averaged in three wells for the horizontal hydraulic conductivity, vertical anisotropy and recharge rate are 7.8 m / day, 225.7 and 0.005 m / day, respectively. Moreover, it was found that the uncertainty of the estimated aquifer properties can be higher due to probable errors in assigning the hydraulic head for constant head boundary. Such uncertainty due to erroneous measurement of pumping rate remained minimum due to the reliable procedure practiced during the pumping test. In addition, sensitivity analysis results show that the hydraulic conductivity is the most significant parameter in the simulation of groundwater flow. Also, it was found that the sensitivity of the aerial recharge is small in this site due to low vertical hydraulic conductivity. For the practical purpose of lowering the water level in the airport area, a relationship was estimated between the pumping rate and the drawdown in the pumping well. Accordingly, it was estimated that a 1 m drawdown level can be achieved by changing the pumping rate to 14.3 L/sec. In conclusion, analytical solutions were found to be less reliable in evaluating aquifer parameters when used complex site conditions such as aerial recharge and strong hydraulic gradient. In such conditions numerical modeling is recommended to be used in simulation of groundwater flow and in estimating aquifer properties.