Do We Need Design Guidance for Mound Systems?

A reader submitted a question recently asking why there was not design guidance for mound systems loaded by gravity. The easy answer is that mound systems are designed to address specific soil and site problems, and a key aspect of their performance depends on pressure distribution of the effluent over both time and space (area). So, there should not be any guidance for gravity distribution because the effluent will not be distributed in a manner to allow adequate treatment.Mounds are designed to address shallow soils over bedrock or some limiting soil layer such as a fragipan or hardpan; slowly permeable