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 Membrane Bioreactors and Chlorine Byproducts. This time you can test your knowledge about settleometer samples and relative density of solutions.
Wastewater Treatment Sample Question
By allowing a settleometer sample to set for several hours after the 30-minute settling test, what can be determined?
A. Denitrification in the system
B. Filamentous identification
C. Septicity and toxicity of sample
D. MLSS concentration
Water Treatment Sample Question
What solution weighs 10.8 pounds per gallon?
A. 48% aluminium sulfate with a specific gravity of 1.3
B. 12.5% sodium hypochlorite with a specific gravity of 1.22
C. 20% hydrogen chloride with with a specific gravity of 1.08
D. 40% Sodium permanganate with a specific gravity of 1.39
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.
