(c) A pumping well was drilled penetrating straight into an unconfined aquifer with the thickness of 42 m. The distance of pumping well with first extraction well and second extraction well are 20 and 180 m, respectively. Meanwhile, the drawdown for the first extraction well is 4.5 m, and the second extraction well is 1.5 m. The constant pumping rate has been set at 0.09 m³/s. (i) Sketch the cross section of unconfined aquifer system and label the values. (ii) Determine hydraulic conductivity of the groundwater through the soil media when it was being pumped out and classify the type of soil according to TABLE Q1(c). (iii) Point out THREE (3) negative effects that might happen for over - pumping aquifers.

(c) A pumping well was drilled penetrating straight into an unconfined aquifer with the thickness of 42 m. The distance of pumping well with first extraction well and second extraction well are 20 and 180 m, respectively. Meanwhile, the drawdown for the first extraction well is 4.5 m, and the second extraction well is 1.5 m. The constant pumping rate has been set at 0.09 m³/s. (i) Sketch the cross section of unconfined aquifer system and label the values. (ii) Determine hydraulic conductivity of the groundwater through the soil media when it was being pumped out and classify the type of soil according to TABLE Q1(c). (iii) Point out THREE (3) negative effects that might happen for over - pumping aquifers.

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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A pumping test in an aquifer has yielded the following data: A pumping well with a diameter of 15 cm pumps at a rate of 12 m³/day, and draws the aquifer down by 3.6 m. Drawdown at a monitoring well 20 m away is 1.1 m. a) Calculate the Transmissivity of the aquifer. Assume this number is representative of the entire aquifer. b) Determine saturated hydraulic conductivity, and identify a soil type from table 7.2 in the Margulis book. The aquifer thickness is 20 m. ●
An unconfined aquifer is 10 m thick and is being pumped so that one observation well placed at a distance 76 m shows a drawdown of 0.5 m. On the opposite side of the extraction well is another observation well 100 m from the extraction well, shows a drawdown of 0.3 m. Assume the coefficient of permeability of 50 m/day. a.) What is the discharge f the extraction well? b.) Suppose the well at 100 m from the extraction well is now pumped. Show with a sketch what this will do to the drawdown. c.) Suppose the aquifer sits on an aquaclude that has a slope of 1/100. Show with a sketch what this will do to the drawdown.
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