Florida Wastewater Practice Test

Which of these would likely indicate an upset condition in a wastewater treatment process?

1. Consistent BOD readings

2. Sustained aeration

3. Excessive foam production

4. Stable pH levels

The correct answer is: Excessive foam production

Excessive foam production is a strong indicator of an upset condition in a wastewater treatment process. In normal operations, foam may form due to the biological activity within the system; however, an unusual increase in foam can signify issues such as the presence of surfactants, a sudden change in the composition of the wastewater, or a disruption in the microbial community. Such conditions can lead to inefficient treatment, as excessive foam can hinder the interaction between microbes and the wastewater, decrease oxygen transfer, and potentially overflow treatment tanks. On the other hand, consistent BOD readings, sustained aeration, and stable pH levels typically suggest a stable and functioning treatment process. Consistent BOD readings indicate that the biological demand is predictable, sustained aeration indicates that the system is effectively providing oxygen for the microbial populations, and stable pH levels suggest that the biological and chemical processes are functioning without significant fluctuations. These conditions usually reflect a healthy and balanced treatment environment, contrasting with the indicator of excessive foam, which suggests interruptions or disturbances in the system's normal operations.