The static level of water table in an unconfined aquifer was 35m above the underlying impermeable stratum. A 75mm radius well, penetrating the aquifer to its full depth, was pumped at the rate of 28 liters per second. After several weeks of pumping, the drawdown in observation wells 20m and 50m from the well were 3m and 2.5m respectively, and the observed drawdowns were increasing very slowly. (B.Sc., UAE, 1989). a) Assuming equilibrium conditions, estimate the hydraulic conductivity and transmissivity of the aquifer. b) Estimate the drawdown just outside the pumped well.

The static level of water table in an unconfined aquifer was 35m above the underlying impermeable stratum. A 75mm radius well, penetrating the aquifer to its full depth, was pumped at the rate of 28 liters per second. After several weeks of pumping, the drawdown in observation wells 20m and 50m from the well were 3m and 2.5m respectively, and the observed drawdowns were increasing very slowly. (B.Sc., UAE, 1989). a) Assuming equilibrium conditions, estimate the hydraulic conductivity and transmissivity of the aquifer. b) Estimate the drawdown just outside the pumped well.

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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