What can lead to the failure of a drain field?

The failure of a drain field can indeed be attributed to excessive water usage and heavy soil compaction. When too much water is introduced into a drain field, it can overwhelm the system's ability to absorb and filter the wastewater. This can saturate the soil, leading to a buildup of water on the surface and potential backup in the septic system.

Heavy soil compaction can exacerbate this issue by reducing the soil's porosity. Compacted soil is less able to absorb water, which can impede the movement of effluent from the drain field into the surrounding soil. When the soil cannot effectively treat and filter the wastewater, it can result in system failure, leading to inadequate wastewater treatment and potential contamination of groundwater.

On the other hand, the other answer choices highlight practices that actually promote the longevity and effectiveness of a septic system, such as proper installation, routine pumping, and the use of biodegradable products. These practices help maintain a properly functioning system, contrasting with the detrimental effects of excessive water use and compaction.