What design practice should be considered for mound systems in relation to drainage?

When designing mound systems for septic installations, it is essential to evaluate both upgradient and downgradient drainage constraints. This practice acknowledges the influence that water movement and soil characteristics have on the effectiveness of a mound system. By assessing drainage factors, installers can ensure that the system will function properly, minimizing the risk of over-saturation, which can lead to system failure or environmental contamination.

This evaluation helps identify potential sources of water that could impact the mound's performance, such as surface water flow, groundwater levels, and the proximity of nearby drainage systems. Proper consideration of these constraints allows for effective placement of the mound, ensuring that it maintains its ability to treat wastewater adequately through natural processes, while also protecting the surrounding environment.

Other options focus on concentration of wastewater, site topography, or installing only on flat surfaces, which don't directly address the critical need to analyze drainage conditions that play a significant role in the sustainability and effectiveness of mound systems.