How is the effluent distributed in a mound soil absorption system?

In a mound soil absorption system, the effluent is distributed through perforated pipes that are laid within a bed of gravel or sand. This design allows for effective dispersion of the wastewater into the surrounding soil, facilitating proper absorption and treatment. The perforated pipes are critical as they enable the effluent to seep out evenly, maximizing the contact with the soil for optimal filtration and biological treatment.

The use of gravel or sand provides a structure that supports the pipes while also improving the movement of effluent. This ensures that the liquid does not pool or cause saturation in one spot, which could undermine the system's efficiency and lead to potential failures. The absorption process relies heavily on the soil's natural characteristics, and the perforated pipes facilitate a gradual release of effluent, encouraging the natural breakdown of contaminants by microbial action in the soil.