Question

Match List-I with List-II regarding groundwater aquifers and their properties:

• A.

  List-I	List-II
  (A) Confined aquifer	(I) Water table well
  (B) Semiconfined aquifer	(II) Piezometric level
  (C) Perched water table	(III) Delayed yield
  (D) Unconfined aquifer.	(IV) Above main water table.

• B.

  List-I	List-II
  (A) Confined aquifer	(I) Piezometric level
  (B) Semiconfined aquifer	(II) Delayed yield
  (C) Perched water table	(III) Above main water table
  (D) Unconfined aquifer.	(IV) Water table well.

• C.

  List-I	List-II
  (A) Confined aquifer	(I) Above main water table
  (B) Semiconfined aquifer	(II) Water table well
  (C) Perched water table	(III) Piezometric level
  (D) Unconfined aquifer.	(IV) Delayed yield.

• D.

  List-I	List-II
  (A) Confined aquifer	(I) Delayed yield
  (B) Semiconfined aquifer	(II) Above main water table
  (C) Perched water table	(III) Water table well
  (D) Unconfined aquifer.	(IV) Piezometric level.

Hint:

Associate Confined aquifer with pressure head (Piezometric level) and Unconfined aquifer with atmospheric pressure (Water table well) to quickly solve matching questions on aquifers.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Aquifers are geological formations that can store and transmit water in usable quantities.
They are classified based on boundary conditions, which dictate how water is released and the height to which water rises in a well.

Step 2: Detailed Explanation:
Let us match each aquifer type with its corresponding property:
- Confined Aquifer: This aquifer is bounded both above and below by impermeable strata, keeping the water under pressure.
When a well penetrates a confined aquifer, water rises to a level higher than the top of the aquifer, known as the piezometric level.
Thus, Confined aquifer matches with (II) Piezometric level.
- Semiconfined Aquifer: This is a leaky aquifer bounded by a semi-pervious aquitard layer.
During pumping, water leaks vertically through the aquitard, which can cause a delay in groundwater release, known as delayed yield.
Thus, Semiconfined aquifer matches with (III) Delayed yield.
- Perched Water Table: This occurs when an impermeable clay lens sits above the main water table, trapping a local zone of saturated soil above the regional groundwater level.
Thus, Perched water table matches with (IV) Above main water table.
- Unconfined Aquifer: This aquifer has a free water surface exposed to the atmosphere.
Wells drilled into these aquifers are simple gravity wells or water table wells.
Thus, Unconfined aquifer matches with (I) Water table well.

Step 3: Final Answer:
The correct matching sequence is: (A) - (II), (B) - (III), (C) - (IV), (D) - (I).