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• The aquifer is homogeneous and isotropic <br /> • The pumping well fully penetrates the aquifer <br /> ' - Discharge from the well is at constant rate <br /> • There is no storage within the well itself <br /> ' Hantush and Jacob (1955) generalized Theis' work to include solutions for aquifers in which the <br /> ' upper confining aquitard allows leakage from an overlying aquifer into the aquifer being tested <br /> Hantush and Jacob (1955) took into account the amount of leakage being tested Leakage results <br /> in a more complicated well function The well function determined by Hantush and Jacob (1955) <br /> ' can be written in terms of two variables, u and the dimensionless parameter r/B, defined by the <br /> relation <br /> ' r K' <br /> r K 6 h` [4l <br /> ' 1 1 <br /> ' where <br /> K' = hydraulic conductivity of overlying aquitard <br /> K- = hydraulic conductivity of the aquifer being tested <br /> b' = thickness of the overlying aquitard <br /> ' b, = thickness of the aquifer being tested <br /> ' The general equation for the drawdown within an aquifer receiving leakage through an overlying <br /> ' aquitard is <br /> s = 4QT W(u,rlB) <br /> [5] <br /> ' where W(u,r/B) is known as the leaky well function Note If K=0 (e g , the overlying aquitard is <br /> impermeable, and there is no leakage), then the leaky aquifer solution reduces to the Theis solution <br />' In addition to the assumptions made by Theis, Hantush and Jacob (1955) assumed that the <br /> storativity of the aquitard (S '), is zero Depending on the value of r/B used in the leaky well <br />' function, the shape of the curve created by plotting u vs W(u,r/B) will change A larger value of r/B <br /> 281$R034 070 H[101 <br /> GROUNDWATER <br />' LIF=TECHNOLOGY, INC <br />