What is the minimum depth required for a standard absorptive drainfield?

In the context of on-site sewage facilities, the minimum depth required for a standard absorptive drainfield is 18 inches. This depth is essential because it ensures adequate functioning of the drainfield while allowing for proper treatment of wastewater. At this depth, the effluent can adequately percolate through the soil layers, where microbial activity occurs to break down contaminants.

Having the drainfield at the correct depth also helps to prevent issues such as clogging and allows for effective drainage without disrupting groundwater or surface water. Inadequate depth could lead to insufficient treatment and potential environmental contamination, which is why knowing the standard depth is critical for both installation and long-term operation of these systems.