Georgia Septic Installer Practice Test

What two processes occur within the septic tank during waste treatment?

1. Filtration and oxidation

2. Evaporation and settling

3. Sedimentation and anaerobic decomposition

4. Composting and fermentation

The correct answer is: Sedimentation and anaerobic decomposition

The correct answer highlights two critical processes that take place within a septic tank: sedimentation and anaerobic decomposition. Sedimentation refers to the process where solid waste materials settle at the bottom of the septic tank due to gravity, forming a layer of sludge. This is crucial because it helps separate the heavier solids from the liquid effluent, allowing for cleaner wastewater to flow into the drain field for further treatment. Anaerobic decomposition is another vital process that occurs in the septic tank. This process involves bacteria that thrive in environments without oxygen, breaking down the organic matter in the wastewater. These anaerobic bacteria decompose the solids in the tank, reducing their volume and converting them into simpler compounds, a crucial step to minimize the amount of waste that must be sent through the system. This dual process not only helps manage the waste more effectively but also helps maintain the septic system's overall function and longevity. The other options involve processes that either do not accurately describe what occurs in a septic tank or refer to processes that happen in different systems or settings, such as filtration or composting, which are not primary functions of a septic tank during the treatment of wastewater.