I have noticed in a number of recent articles that the onsite sewage treatment industry is moving toward very wide beds in mounds and other wide systems with a series of beds. I am concerned that this is a very dangerous trend and I predict hydraulic failure of these wide mounds when flows are near or at design values.Mounds designed for single-family residences have been used successfully for years when the rock layer width does not exceed 10 feet. For a mound to work properly it is important that effluent is distributed through the clean sand layer to the underlying
