How deep must the mantle of a raised filter bed be placed into the original soil?

The requirement for the mantle of a raised filter bed to be placed into the original soil is set at a depth of 6 inches. This depth is crucial for several reasons. First, it ensures adequate performance of the septic system by allowing the necessary infiltration and treatment of wastewater. By extending the mantle to this specific depth, it permits sufficient contact between the wastewater and the soil, which aids in the biological processes that treat the effluent.

Additionally, a 6-inch depth helps to establish a stable base for the raised filter bed, minimizing the risk of settling or uneven distribution of wastewater, which can lead to system failure. It strikes a balance between providing enough depth for proper filtration while avoiding complications that may arise from placing the mantle too deep or too shallow.

Understanding these technicalities emphasizes the importance of adhering to established guidelines in the installation of septic systems to promote effective and safe wastewater management.