What treatment performance can a properly maintained mound system achieve at minimum?

A properly maintained mound system, which is a type of alternative onsite sewage treatment and disposal system, can achieve at least Treatment Level B performance. This level indicates that the system is functioning effectively to treat wastewater before it is released into the environment.

Mound systems are designed to handle effluent by effectively treating it as it moves through the soil layers. They utilize a specially constructed mound of soil to raise the absorption area above the natural ground level, allowing for effective aeration and filtration of the wastewater. When the system is properly maintained—such as by ensuring the distribution of wastewater is even, monitoring for blockages, and following maintenance protocols—its efficiency in treating the effluent can meet or exceed the parameters defined for Treatment Level B.

Treatment Level B generally indicates that the system is capable of removing a significant portion of contaminants, including total suspended solids and biochemical oxygen demand. Achieving this level suggests reliable treatment performance, which is critical for protecting public health and the environment.

In contrast, levels above B, such as A, indicate even higher treatment standards, which are not typically the minimum performance expected from a mound system. The choice of no treatment performance is inconsistent with the function of a mound system, which is precisely designed to treat wastewater. Therefore,