What might be a consequence of inadequate aeration in a treatment system?

Inadequate aeration in a treatment system can lead to increased odor problems due to insufficient oxygen levels for aerobic bacteria to effectively break down organic materials. When oxygen is limited, anaerobic bacteria can become more prevalent. These anaerobic processes often produce hydrogen sulfide and other volatile organic compounds, which are responsible for unpleasant odors. This is particularly problematic in wastewater treatment, where maintaining adequate aeration is crucial for controlling odors and ensuring that the treatment process operates efficiently.

The other options do not align with the consequences of inadequate aeration. Improved effluent quality typically requires sufficient aeration to support aerobic digestion of waste. Lower energy costs would generally not be a result of inadequate aeration; in fact, proper aeration can optimize energy use by ensuring that the treatment process runs efficiently. Enhanced microbial activity is also linked to proper aeration levels, as aerobic microorganisms thrive in oxygen-rich environments. Therefore, the indication of increased odor problems accurately captures a significant consequence of inadequate aeration in a treatment system.