A 30 cm well penetrates 30 m below static water level. After a long period of pumping at a rate of 1800 lit/min, the drawdowns in the observation wells at 12 m and 36 m from the pumped well are 1.2 m and 0.5 m, respectively. Determine: A. The transmissibility of the aquifer B. The drawdown in the pumped well assuming R = 300 m. C. The specific capacity of the well.

A 30 cm well penetrates 30 m below static water level. After a long period of pumping at a rate of 1800 lit/min, the drawdowns in the observation wells at 12 m and 36 m from the pumped well are 1.2 m and 0.5 m, respectively. Determine: A. The transmissibility of the aquifer B. The drawdown in the pumped well assuming R = 300 m. C. The specific capacity of the well.

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 20-cm well ponetrates 30 m below static water level (GWT). After a long period of pumping at a rate of 1800 Ipm, the drawdowns in the observation wells at 12 m and 36 m from the pumped well are 1.2 m and 0.5 m, respectively. Determine: (1) (1) the transmissibility of the aquifer. the drawdown in the pumped well assuming R = 300 m. the specific capacity of the well
Question- Three tube wells of 25 cm, diameter each are located at the three vertices of an equilateral triangle of side 100 m. Each tube well penetrates fully in a confined aquifer of thickness 25 m. Assume the radius of influence for these wells and the coefficient of permeability of the aquifer as 300 m and 40 m/day respectively. Calculate the discharge when only one well is pumping with a drawdown of 3 m. (i) (ii) (iii) What will be the percent change in discharge of this well if all the three wells were to pump such that the drawdown is 3 m in all the wells?
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A pump out test is carried out in a perforated well of 30 cm in diameter, extending into an impervious zone, and through an aquifer 17 m thick from the ground surface. The phreatic line is at 4 m below ground-surface level. After 24 hours of continuously pumping water out of the well, equilibrium has been reached. The discharge of the pump is 5.4 cu.m/hr and the drawdown is 4 m. The radius of influence R was estimated to be 15 m. Determine the average coefficient of permeability of the soil.
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