What characterizes an artesian well?

• A. A well tapping pressurized water from a confined aquifer
• B. A well where water is pumped from the surface
• C. A shallow well that does not require casing
• D. A well that does not require any pressure for water extraction

Answer: (A)

An artesian well is defined by its ability to draw water from a pressurized confined aquifer, meaning that the water in the aquifer is under enough pressure that it can rise to the surface naturally without the need for pumping. This occurs when the aquifer is sandwiched between impermeable layers of rock or clay, which helps to maintain that pressure. When a well is drilled into this aquifer, the pressure may cause the water to flow freely to the surface, or it may rise partially up the well, depending on the level of pressure.

This characteristic is what sets artesian wells apart from other types of wells. In contrast, wells that require pumping or are not associated with pressurized aquifers would not be classified as artesian. Understanding the mechanics of artesian wells is essential for environmental health specialists as it relates to groundwater management, potential contamination sources, and the sustainable use of water resources.