Determination of Unconfined Aquifer Parameters Using Boulton, Neuman and Streltsova Methods

Abstract

Analysis of pumping test data to estimate aquifer parameters is normally carried out using standard procedures such as the Theis or Jacob method. These methods, however, were derived with assumptions regarding the type of aquifer and wells that may not be satisfied under some conditions. In unconfined aquifers the effects of delayed yield, partial penetration of wells and other effects make the use of Theis or Jacob methods impractical in many cases. The objective of this work is to analyze pumping test data from seven different well sites of five wadis taking into consideration the effects of delayed yield, partial penetration of wells and the decreased saturated thickness. The methods of Boulton, Neuman and Streltsova were applied on pumping test data from the five unconfined aquifers in the south-western part of Saudi Arabia. The aquifer parameters resulting from the three methods were evaluated and compared to each other. Using the resulting values of aquifer parameters, the drawdowns were recalculated and compared to the original data in order to define best values of aquifer parameters for the seven test sites.