Which of the following statements is true about confined aquifers?

Confined aquifers are characterized by being surrounded by impermeable layers, which create pressure within the aquifer and often lead to the phenomenon where water rises in a well above the level of the aquifer itself when tapped.

When drilling a well into a confined aquifer, it is ideal for the well to fully penetrate between the impermeable layers above and below the aquifer. This allows for maximum water throughput and minimizes issues associated with lower hydraulic conductivity at the boundaries. By ensuring full penetration, the well can capture the entire water column available in the confined aquifer, which can provide better yield and more stable water levels.

The other statements present various misconceptions about confined aquifers. For example, a well site located in a recharge area is characteristic of unconfined aquifers, where surface water can easily seep into the aquifer; this is less applicable to confined aquifers. Furthermore, well penetration is typically complete rather than partial to optimize water extraction. Lastly, contamination in confined aquifers tends to spread more slowly compared to unconfined aquifers because the impermeable layers act as barriers against rapidly moving contaminants. Thus, the statement that the well should fully penetrate between impervious layers reflects the fundamental understanding of how to effectively utilize confined aquifers.