Problem 3 - A 20 cm-diameter extraction well is drilled in an unconfined aquifer. The elevation of the bottom of the aquifer is at +35 m, MSL (mean sea level). The aquifer is assumed homogeneous and testing of the well shows that the aquifer's soils have a coefficient of permeability of 5x101 cm/sec. A pump is then installed into the well and water is pumped out at a steady-state rate of 1000 m³/day. At steady-state after pumping starts, the water level at the extraction well lowers to Elevation +65 m, MSL. What would be the approximate elevation of the water table at an observation well that is expected to be drilled 40 m of distance from the extraction well? IK (h} – h3) Q = In

Problem 3 - A 20 cm-diameter extraction well is drilled in an unconfined aquifer. The elevation of the bottom of the aquifer is at +35 m, MSL (mean sea level). The aquifer is assumed homogeneous and testing of the well shows that the aquifer's soils have a coefficient of permeability of 5x101 cm/sec. A pump is then installed into the well and water is pumped out at a steady-state rate of 1000 m³/day. At steady-state after pumping starts, the water level at the extraction well lowers to Elevation +65 m, MSL. What would be the approximate elevation of the water table at an observation well that is expected to be drilled 40 m of distance from the extraction well? IK (h} – h3) Q = In

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter7: Permeability

Section: Chapter Questions

Problem 7.22P: Refer to Figure 7.24. The following data were collected during the field permeability measurement of...

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An unconfined aquifer is 100 feet thick was evaluated using a field pumping test. The depth to groundwater is 10 feet. At a distance of 1000 feet, the drawdown was 40 feet, and at a distance of 5000 feet it was 20 feet. Find the permeability of the aquifer assuming that a steady-state of 960 gal/minute during the test in ft/sec.
Refer to Figure 7.24. The following data were collected during the field permeability measurement of a confined aquifer using a pumping test. Determine the hydraulic conductivity of the permeable layer. Use Eq. (7.49). Thickness of the aquifer, H = 4.5 m Piezometric level and radial distance of the first observation well: h1 = 2.9 m; r1 = 17.8 m Piezometric level and radial distance of the second observation well: h2 = 1.8 m; r2 = 8.1 m Rate of discharge from pumping, q = 0.5 m3/min
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