Elevated Sand Mounds
An elevated sand mound is often utilized on sites where redox features in the soil indicate a limiting zone caused by a seasonal high water table, or shallow rock formations. The Pennsylvania Department of environmental protection mandates that untreated septic effluent maintain a secondary treatment zone of 48 inches. That is a minimum of 48 inches from where the effluent leaves the delivery lateral to the depth where the limiting zone has been determined to exist. Where less than 48 inches of virgin soil is naturally present to meet the DEP requirements, DEP certified sand fill is used to elevate the untreated water to the point of minimum separation. In order to achieve even distribution of the effluent to the gravel bed on top of the DEP certified sand, a dosing tank is utilized where a pump which has been properly sized to deliver the water to the field with sufficient pressure to spray into the gravel thru a series of ¼ inch holes drilled on six ft. centers in pipes that form a grid pattern called laterals. A elevated sand mound is a proven, reliable technology, that we have been installing since 1973.