Question

Specific storage refers to

1.  volume of water stored in the unit volume of aquifer 
2. water that a portion of an aquifer releases from storage, per unit mass or volume of aquifer, per unit change in hydraulic head, while remaining fully saturated.
3.  volume of water drained by gravity per unit volume of aquifer
4. the difference between field capacity and evapotranspiration

Answer 1

Correct Answer - Option 2 : water that a portion of an aquifer releases from storage, per unit mass or volume of aquifer, per unit change in hydraulic head, while remaining fully saturated.

Explanation

Specific yield: It is defined as the volume of water released from storage by an unconfined aquifer per unit surface area of aquifer per unit decline of the water table.

Specific Capacity: It is defined as the rate of flow through the well per unit drawdown that has determined for initial first meter fall of water in well.

Specific storage: It is the amount of water that a portion of an aquifer releases from storage, per unit mass or volume of aquifer, per unit change in hydraulic head, while remaining fully saturated.

The discharge corresponding to the critical head is called as critical or maximum yield. Allowing a factor of safety a working head is specified and the corresponding yield is from well is known as safe yield.