Tennessee Wastewater Operator Practice Exam

What is not a method for removing pathogenic bacteria from wastewater?

1. Chemical treatment

2. Natural die-off

3. Overfeeding nutrients

4. Sedimentation or filtration

The correct answer is: Overfeeding nutrients

The option selected is considered correct because overfeeding nutrients in a wastewater treatment process does not effectively remove pathogenic bacteria. In fact, providing excess nutrients can lead to conditions that promote microbial growth, including potentially harmful bacteria, rather than reducing their presence. This overabundance often results in a more developed biomass and can lead to more significant sanitation issues. In contrast, chemical treatment methods involve using disinfectants or other substances that can effectively kill or inactivate pathogens present in the wastewater. Natural die-off refers to the phenomenon where bacteria die out over time due to unfavorable conditions, which can also contribute to reducing pathogenic levels as the system operates. Sedimentation or filtration are physical processes that help to separate solids and can likewise help to remove bacteria through trapping or straining them out. Each of these methods plays a valid role in the overall goal of treating wastewater and reducing harmful pathogens, thereby enhancing public health safety.