Tank and Mound
As discussed above, the household plumbing collects the wastewater and sends it to the septic tank where it is separated into the three layers, sludge, scum and wastewater. Once the wastewater enters the effluent dosing chamber of the septic tank, the pump in the effluent dosing chamber delivers the effluent to the mound system. In a mound, pressure distribution pipes are placed in a bed of aggregates or chambers with a 12″ layer of sand below. The wastewater is pumped into the pressure distribution system and sprays into the sand layer, where aerobic bacteria cleans the water. The mound must be above ground and must have a separation of three feet between the bottom of the sand layer and and a restrictive layer or water table. Mounds must be landscaped with grass and be regularly maintained in order to have improved efficiency.
