CWEA Environmental Compliance Practice Test

The biological treatment process is essential in wastewater treatment for the removal of organic matter. This process typically employs microorganisms to break down organic pollutants in the wastewater. During biological treatment, bacteria and other microorganisms consume organic materials as their food source, effectively reducing the concentration of these substances in the water. This method is highly effective because it mimics natural processes that occur in the environment, thus promoting the degradation of organic matter.

In contrast, the other options serve different functions in the wastewater treatment process. Sedimentation tanks are primarily used to settle out solid particles from the wastewater but do not specifically target organic matter degradation. Screening is a preliminary step that involves removing large debris and solids from incoming wastewater, focusing on protecting downstream equipment rather than treating organic contaminants. Chlorination is a disinfection process meant to eliminate pathogens in treated water, ensuring it is safe for release into the environment; however, it does not remove organic matter.

Understanding the biological treatment process is key to comprehending the overall efficiency of wastewater treatment in managing organic load and maintaining environmental compliance.