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Discussion of Applicable Equations <br /> ' Below are stated the equations referred to in Section 5 2 above We have provided these <br /> equations as a review of possible equations that we will use in this aquifer pumping test <br /> ' investigation <br /> Equation(1) is the Theis or non-equilibrium equation <br /> ' s (Q/47rT)J,, e"du/u) (1} <br /> where <br /> u=(rzS/4Tt) (2) <br /> ' s= "drawdown" <br /> u= "well function" <br /> Q=constant well discharge <br /> ' T=transmissivity <br /> S= storage coefficient(for confined aquifers) or specific yield <br /> (for unconfined aquifers) <br /> ' t=time since beginning of pumping <br /> r=radius <br /> (Source Todd, David K, 1980, Groundwater Hydrology, 2nd Edition, John Wiley & Sons, Inc , <br /> ' New York,p 121f However,this basic equation is referred to inmost groundwater books) <br /> While the non-equilibrium equation deals with drawdown caused by radial flow in aquifers with <br /> horizontal water table or piezometric surface, the following set of equations define the equilibrium <br /> radius of influence laterally (YL), downgradwnt (XL), and upgradient (2 71 X,,) of a pumping well in <br /> an aquifer with uniform flow,that is with a sloping surface These equations can therefore be used to <br /> produce data needed to draw a flow net for the capture zones in a water extraction system K is a key <br /> parameter in these equations <br /> -(y/x) tan (21rKhoi/Q)y (3) <br /> ' The finite lateral limit for y is <br /> YL=f(Q/2KhOi) (4) <br /> ' The "stagnation point" (flow divide) downgradient is <br /> X4= -(Q/2nKhoi) (5) <br /> ' and the upgradient inflow limit at any one time is <br /> 27A, (6) <br /> ' Where <br /> K=hydraulic conductivity <br /> Q=well discharge <br /> ' i=natural slope of the water table <br /> ho=uniform saturated aquifer thickness <br /> y= maximum distance of influence laterally from well <br /> x=maximum distance of influence down gradient from well <br /> ' (Source as above) <br /> I� <br />