Sensitivity coefficients, which are a measure for the relationship between a change in drawdown and a change in the parameter distribution, allow the analysis of the intrinsic characteristics of pumping tests in order to provide a better understanding of their response to aquifer heterogeneity.
The evaporation rate in this solution was described as a function of shallow water table depth drawdown using the parameters of Campbell's soil water retention model.
Table 1 presents a summary of the well and reservoir data of a designed BHP obtained from the examples of application well test software (Windowstm Application Well test Software 1995) simulating the drawdown test using parameters in Table 1.
The objective is to minimize predictive uncertainty (variance) of the estimated stream depletion, which depends on the sensitivities of depletion and drawdown to relevant hydrogeologic parameters.
Other parameters, including drawdown, in-situ stress, and perforation orientation, are shown to have considerable influence on sand production rate and are discussed in this paper.
The study of Christensen [Christensen, S., 2000. On the estimation of stream flow depletion parameters by drawdown analysis. Ground Water 38 (5), 726 734], based on the solution of Hunt [Hunt, B., 1999. Unsteady stream depletion from groundwater pumping. Ground Water 37 (1), 98 102], analyzed three streamflow depletion parameters T, S, and λ of a simplified stream-aquifer system.
The new solution permits determination of the influence of fractures, matrix blocks and watertable drainage parameters on the aquifer drawdown.
Comparing the calibration results for the two alternative models showed that they fit the drawdown observations nearly equally well, and most estimated parameter values are realistic and nearly identical.
Approximate analytical solutions for the drawdown were obtained and the impacts of different parameters on the drawdown were analyzed.
Additionally, both the hydraulic conductivity and thickness of the aquifer are the most sensitive parameters in influencing the predicted dimensionless drawdown.
