How should the casing height above the ground surface be configured?

The appropriate casing height above the ground surface is crucial for preventing contamination of the water supply from surface runoff, debris, or pests. A casing height of at least 18 inches above ground is designed to provide a sufficient barrier to keep surface water, which may carry pathogens or pollutants, from entering the well. This measurement helps ensure that the well remains sanitary and protects the water quality for its intended use.

Having the casing height set to this standard balances the need for accessibility and protection from potential contaminants. If the casing is too low, it becomes more susceptible to flooding and other environmental factors that could compromise the well's integrity.

Higher casing heights, while offering greater protection, may not be necessary in many situations and could lead to practical issues, such as difficulty in accessing the well for maintenance or repairs. Thus, the choice of at least 18 inches effectively meets health and safety standards while considering operational usability.