A pumping test was made in sands extending to a depth of 20m where an impermeable stratum was encountered. The initial ground-water level at the ground surface. Observation wells were sited at distance of 4 and 9m from the pumping well. A steady state was established at about 20 hours when the discharge was 4.20 liters per second. The draw downs at the two observation wells were 1.7m and 0.85m. Calculate the coefficient of permeability. original ground water level] (level at ground surface) 9m 4m Q= 4.2 liters/s o.85 20m h2 SAND

A pumping test was made in sands extending to a depth of 20m where an impermeable stratum was encountered. The initial ground-water level at the ground surface. Observation wells were sited at distance of 4 and 9m from the pumping well. A steady state was established at about 20 hours when the discharge was 4.20 liters per second. The draw downs at the two observation wells were 1.7m and 0.85m. Calculate the coefficient of permeability. original ground water level] (level at ground surface) 9m 4m Q= 4.2 liters/s o.85 20m h2 SAND

Fundamentals of Geotechnical Engineering (MindTap Course List)

5th Edition

ISBN:9781305635180

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter6: Hydraulic Conductivity

Section: Chapter Questions

Problem 6.15P

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A pumping test was made in a sand layer extending to a depth of 16m. The initial groundwater table was located 2m below the ground surface. Observation wells were sighted at distances 4m and 9.5m from the pumping well. Using a discharge of 0.4 cubic meters per hour, a steady level is attained at the pumping well. The measured drawdowns at the two observation wells are 2m and 0.25m respectively. Solve the hydraulic head 5m from the pumping well.
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) A pumping test carried out in a 50 m thick confined aquifer resulted in a flow rate of 600l/min. The thickness of the impermeable layer above the aquifer is 20 m and the originalwater level in the well was 2 mm below the ground surface (which is also the top of theimpermeable layer). Drawdowns in two observation wells located 50 m and 100 m fromthe 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.
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