a pump test is conducted in a leaky confined aquifer. the confining layer has a thickness of 1.5 m, while the aquifer has a thickness of 10 m. the well is pumped at 1000 m3/d, and it has a radius of 0.6 m. the drawdowns at 30 and 75 m from the well are 0.4 m and 0.25 m, respectively. determine the hydraulic conductivities of the aquifer and the confining layer