Subsurface hydrology terminology Pick the correct set of statements about groundwater zones and pressures.

Introduction / Context:
Hydrogeology distinguishes layers by their moisture content and pressure conditions. Correct terminology helps interpret well logs, pumping tests, and infiltration processes.

Given Data / Assumptions:

• Unconfined conditions for the water table concept.
• Standard definitions used in groundwater hydrology.

Concept / Approach:
The subsurface is divided broadly into a zone of aeration (vadose) above the water table and a zone of saturation below. Below the water table, pores are fully saturated and the pore water pressure is positive (hydrostatic at rest).

Step-by-Step Solution:

Verification / Alternative check:
Textbook phreatic surface definition: the water table is where pore pressure equals atmospheric (gauge = 0). Below it, pore pressure is positive and increases with depth according to hydrostatics.

Why Other Options Are Wrong:
Not applicable; options a–d are all correct, making option e the best choice.

Common Pitfalls:
Confusing capillary fringe (often saturated but under suction) as part of the vadose zone above the water table.

Final Answer:
All of the above