Welcome back to TPO magazine's Exam Study Guide Series, which offers a pair of water/wastewater study questions with in-depth explanations of the answers. Last time, we covered a set of wastewater and drinking water treatment questions on the topics of Pipe-Wall Bacteria and Chemical Water Softening. This time you can test your knowledge about disinfection processes and carbon dioxide concentrations.

Wastewater Treatment Sample Question

What superior disinfection process is created on-site, is done in an enclosed tank, and requires off-gases to be destroyed before release to the atmosphere?

A. Ozonation
B. Chlorine
C. Peracetic acid
D. Ultraviolet radiation

Water Treatment Sample Question

In most instances, which water source would contain the highest carbon dioxide concentration? 

A. Shallow surface water 
B. Shallow well water
C. Deep well water
D. Carbon dioxide is not dissolved in source waters and is only a greenhouse gas concern

To see answers for both of the above questions, click this link.

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About the authors: 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. Lallish was also named the 2017 Illinois Operator of the Year and 2018 president of the Illinois Association of Water Pollution Control Operators.

Drew Hoelscher is the program director of drinking water operations at the Environmental Resources Training Center in Edwardsville, Illinois.