Georgia Septic Installer Practice Test

What type of treatment does a septic tank primarily provide?

1. Physical separation

2. Bacterial breakdown

3. Chemical treatment

4. Filtration

The correct answer is: Bacterial breakdown

A septic tank primarily provides bacterial breakdown as its main type of treatment. In a septic system, waste enters the tank, where it is held for a period of time. During this time, anaerobic bacteria— which thrive in environments without oxygen—begin to break down the organic matter present in the waste. This biological process significantly reduces the solids and enhances the overall treatment of the wastewater before it moves onto the next stage of the system, often to the drain field where further treatment occurs. While physical separation does play a role in the initial functioning of a septic tank by allowing solids to settle to the bottom, the main function is the biological breakdown of waste by bacteria. Chemical treatment and filtration are not primary functions of the septic tank; instead, they refer to other types of wastewater treatment methods or processes that may occur downstream of the septic tank.