Question

could you please help with question #2?

2. A confined aquifer has a specific storage of 2.5 x 10ml and a thickness of 27 m. How much water would it yield if the potentiometric surface declined an average of 4.3 m over a circular area with a radius of 950 m? Recall that the area of a circle = ttrº [6 pts) 3. The hydraulic conductivity of a silty sand was measured in a laboratory permeameter and found to be 3.1 x 10 cm/s at 22 °C. What is the intrinsic permeability, in cm'? Refer to Appendix 14 of the textbook to obtain values for the density and viscosity of water and assume g=980.0 cm/sec. [6 pts]

Answer 1

The specific storage of an aquifer is the volume of water that a unit volume of aquifer releases under a unit decline in head.

So, $specific\;storage\;S = \frac{volume\;of\;water\;stored\; in\; the\; aquifer}{Total\;volume\; the\; aquifer*decline} = \frac{V}{V_{tot}*d}$

So,  $V= S*V_{tot}*d$

S = 2.5*10^-5 m^-1

d = 4.3 m

$V_{tot}=\pi r^2h = 3.14*950*950*27=76513950 m^3$

So, V = 76513950*2.5*10^-5 *4.3 = 8225.24963 m³ of water.