A pumping test carried out in a 50 m thick confined aquifer resulted in a flow rate of 600 l/min. The thickness of the impermeable layer above the aquifer is 20 m and the original water level in the well was 2 mm below the ground surface (which is also the top of the impermeable layer). Drawdowns in two observation wells located 50 m and 100 m from the well are 3 and 1 m respectively. Calculate: i) The coefficient of permeability of the aquifer, ii) The drawdown in the well, iii) The radius of influence. The diameter of the well is 0.6 m.

A pumping test carried out in a 50 m thick confined aquifer resulted in a flow rate of 600 l/min. The thickness of the impermeable layer above the aquifer is 20 m and the original water level in the well was 2 mm below the ground surface (which is also the top of the impermeable layer). Drawdowns in two observation wells located 50 m and 100 m from the well are 3 and 1 m respectively. Calculate: i) The coefficient of permeability of the aquifer, ii) The drawdown in the well, iii) The radius of influence. The diameter of the well is 0.6 m.

Fundamentals of Geotechnical Engineering (MindTap Course List)

5th Edition

ISBN:9781305635180

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter7: Seepage

Section: Chapter Questions

Problem 7.6P

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