QI) An unconfined aquifer has a thickness of 33 m. A fully penetration 20 cm diameter well in the aquifer is pumped at a rate of 33 lit's. The drawdown measured in two observation wells located at a distance of 10 m and 100 m from the well are 7.5 m and 0.5 m respectively. Determine: 1- Sketch the case. 2- the average hydraulic conductivity of the aquifer. 3- At what distance from the well the drawdown is insignificant?

QI) An unconfined aquifer has a thickness of 33 m. A fully penetration 20 cm diameter well in the aquifer is pumped at a rate of 33 lit's. The drawdown measured in two observation wells located at a distance of 10 m and 100 m from the well are 7.5 m and 0.5 m respectively. Determine: 1- Sketch the case. 2- the average hydraulic conductivity of the aquifer. 3- At what distance from the well the drawdown is insignificant?

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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QUESTION 12 1. A 40 cm well completely penetrates an unconfined aquifer of saturated depth 40 m. After a long period of pumping at a steady rate of 0.025 m³/s, the drawdown in two observation wells 20 m and 80 m from the pumping well were found to be 4.0 m and 2.0 m respectively. Determine the hydraulic conductivity of the aquifer. Round off to two (2) decimal places, Fill in the blank_ x 105 m/s
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