03 Exercises Pumping Test AQTESOLV

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t m t m t m Sustainable Use of Underground Energy Resources 2023- 2024 Pumping test - AQTESOLV EX. 1.1 A pumping test is performed by withdrawing water at the constant rate, Q = 0.55 m3/min, from a fully-penetrating well in a confined, isotropic and homogeneous aquifer with constant thickness b = 7 m. The dir ectory Ex_1 contains two files collecting the values of drawdown measured in two piezometers, OW30 and OW90, respectively located 30 m and 90 m far from the pumping well. We assume the pumping well radius to be negligible. Estimate transmissivity, T, and storativity, S of the aquifer. Preliminary analysis: diagnostic plot with Excel. 1) For each observation well, study the experimental curve of drawdown vs time and compute ln- derivative of drawdown vs time according to the following finite-difference scheme: s  ln t m = s(ti +1 ) − s(ti −1 ) , being t ln ti +1 − ln ti −1 = ti +1 + ti −1 2 For the first and last measurements the finite-difference scheme changes to: s  ln t m = s(ti +1 ) - s(ti ) , being t ln ti +1 − ln ti = ti +1 + ti 2 and s  ln t m = s(ti ) − s(ti −1 ) , being t ln ti − ln ti −1 = ti + ti −1 2 Compare the results with the diagnostic plot models collected in Renard (2008). Identify possible early-time or late-time behaviors and the range of straight-line (IARF in Renard, 2008) trend. Infer a first estimate of T from the ln-derivative curve within this range. 2) Use excel to estimate T and S according to the Cooper and Jacob solution. 3) Use the software AQTESOLV to apply Theis curve matching method to the experimental data. Compare all outcomes for T and S obtained with the different methods. Here are reported the basic steps for the software implementation. INSERT PROJECT DATA: File → New → Pumping test wizard Project details: (i) Choose…