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 Settleometer Samples and Relative Density of Solutions. This time you can test your knowledge about rotating biological contactors and PFAS MCLs.
Wastewater Treatment Sample Question
It is recommended that rotating biological contactors be covered for outdoor operations. What is the reason for that recommendation?
A. Odor control
B. Aggressive hydrogen sulfide buildup
C. Prevent the release of fluorocarbons
D. Prevents weather-related problems
Water Treatment Sample Question
What is the maximum contaminant level for PFOA and PFOS?
A. 1 ppt
B. 2 ppt
C. 3 ppt
D. 4 ppt
To see answers for both of the above questions, click this link.
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.
