In Minnesota, we have used mound soil treatment systems for 40 years. Once our installers got over the fact that there were some specific requirements for constructing mounds, and once they saw that mounds required a pump and pressure distribution, we had great success.Mound systems were developed to address several highly specific soil problems while maintaining the desired balance between making the surface water go away and treating the septic tank effluent. The issues addressed by mounds and other aboveground systems such as at-grades are shallow soils over bedrock, slowly permeable clay soils, and high water tables or seasonally saturated
