What happens to solids in the septic tank during the settling process?

During the settling process in a septic tank, solids primarily settle at the bottom due to gravity. This process allows for the separation of different components within the wastewater. Heavier solids, which often consist of organic matter and other debris, form a sludge layer at the bottom of the tank. Meanwhile, lighter materials, such as fats, oils, and greases, tend to float to the surface, creating a scum layer.

The function of the septic tank is to provide a controlled environment for this separation to occur, allowing the solids to be contained while the relatively clearer liquid wastewater flows out into the drain field for further treatment. This settling process is crucial for the effective functioning of a septic system, as it helps to manage waste efficiently and minimize the load on the soil absorption area.

Understanding this settling process is vital for maintaining septic systems, which rely on these physical processes to ensure proper treatment and reduce potential environmental impacts.