When faced with a licensing exam, don't struggle with test anxiety! Use the question below and others from our Exam Study Guide series to properly study and prepare for exam questions. Take a look at this sample wastewater treatment licensing question along with an explanation of the correct answer.

Sample question:

What type of plant is required to make provisions for warning of potential explosions that could result from the presence of combustible gases from wastewater?

A) Orbal oxidation ditch
B) Sequencing batch reactor
C) Contact stabilization
D) High-purity oxygen

Answer: The answer is high-purity oxygen, D. Precautions are also taken in selective construction materials because of the corrosive and reactive nature of the oxygen-CO2 gases.

Source: WEF MOP11 20-21

About the author
Rick Lallish is the Water Pollution Control program director at the Environmental Resources Training Center of Southern Illinois University Edwardsville. He provides training for entry-level operators in the wastewater field and operators throughout the state looking to further their education.