What must be confirmed if the depth of soil to a water table is less than 18 inches?

When the depth of soil to a water table is less than 18 inches, it is critical to confirm that there are at least 12 inches of unsaturated soil during the wet season. This is important because septic systems rely on the soil to treat and filter wastewater, and adequate unsaturated soil is needed to provide proper treatment and prevent groundwater contamination. If the water table is too high, it can lead to system failure and environmental issues.

The requirement for a minimum of 12 inches of unsaturated soil ensures that there is sufficient space for the wastewater to settle and be treated before reaching the water table. This is a regulatory standard in many areas to protect both public health and local water quality, making it essential for septic installers to assess and confirm these conditions before installation.