There must be a minimum of how many feet of undisturbed soil between the septic tank and the nearest trench?

The requirement for a minimum of five feet of undisturbed soil between the septic tank and the nearest trench is based on the need for proper filtration and drainage. This distance is crucial to prevent contaminants from wastewater in the septic tank from migrating into the drainage area, which consists of the trenches.

Having at least five feet of undisturbed soil helps ensure that the effluent from the septic tank is adequately treated as it passes through the soil before reaching the trench. The soil acts as a natural filter, removing harmful pathogens and pollutants. This distance also allows for proper saturation and percolation of water, which is essential for the soil's ability to assimilate the effluent safely.

Inadequate distances may lead to insufficient treatment of wastewater, increasing the risk of environmental contamination and potential health hazards. Therefore, adhering to the five-foot requirement is critical for the effective operation of a septic system and for protecting both public health and the environment.