Texas Wastewater Class B Practice Exam

The most important role of aerobic bacteria in wastewater treatment is to decompose organic matter. Aerobic bacteria thrive in environments where oxygen is present, which allows them to break down complex organic substances present in wastewater into simpler compounds. This decomposition process not only reduces the amount of organic material but also helps to improve the overall quality of the water, making it safer for discharge into the environment or for further treatment.

While the other roles mentioned have significance in the wastewater treatment process, they do not capture the primary function of aerobic bacteria. For example, converting solids to gas involves other processes and could be associated more with anaerobic conditions. Generating energy is a biochemical outcome of the metabolic processes of bacteria, but it is secondary to the primary task of breaking down organic matter. Reducing pathogen levels is also crucial, often accomplished by the combined action of different microorganisms, but aerobic bacteria primarily focus on degrading organic content. Therefore, decomposing organic matter stands out as the most vital role of aerobic bacteria in this context.