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 Laboratory Glassware and Distribution System Piping. This time you can test your knowledge about nutrient deficient influent and softener treatment calculations.
Wastewater Treatment Sample Question
What type of activated sludge treatment process is used when the influent is considered nutrient deficient?
A. Kraus process
B. Al West method
C. Membrane bioreactors
D. High-purity oxygen
Water Treatment Sample Question
A water softener is 5 feet in diameter and has 36 inches of media. The media is rated to remove 20,000 grains of hardness per cubic foot and the water being treated has a total hardness of 450 mg/L as calcium carbonate. Approximately, how many gallons of water can the softener treat before a regeneration is required?
A. 45,000
B. 31,000
C. 27,000
D. 3,000
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.
