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CE 473/573 Groundwater Fall 2007 Comments on homework 7 39. I solved this problem by assuming steady flow: Q0 s= ln 2πT R r , which can be written as s = mx + B, where x = ln r, m=− Q0 , 2πT and Q0 ln R. 2πT I fit a line to s vs. ln r and computed the transmissivity and radius of influence from m and B. This approach gives T = 678 m/d and R = 188 m. To test for steady state, one could solve for the properties using the approach for unsteady flow and compare the answers. One could also check that u < 0.01 or derive a criterion by using scaling to estimate the ratio of the unsteady term and the flux divergence term in the flow equation. B= 40. All groups derived the requested equation properly and computed K. 42. No problems. 45. I matched the plots at (u, W ) = (0.1, 1) and (r 2 /t, s) = (4.2 m2 /s, 1.1m). Then T = 0.01 m2 /s and S = 9.5 × 10−4 . With the Jacob method I find T = 0.013 m2 /s and S = 4.4 × 10−4 using all points and T = 0.011 m2 /s and S = 9.3 × 10−4 using only the points with u < 0.01. The radii of influence computed with the Sichard and Jacob methods are quite different.