Exam Study Guide: Visual Condition Assessment; and New Service Lines

Maintaining your education is important, especially in a career that demands licensing exams. Prove you’re an expert operator by answering these questions and others from our Exam Study Guide Series.

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 Biological Activity in Lagoons; and Calcium Hardness Calculation. This time, you can test your knowledge about visually assessing the conditions of activated sludge facilities, and tapping water distribution mains for new service lines.

Wastewater Treatment Sample Question

During the afternoon plant walkthrough, you notice a thin, light-tan foam covering approximately 10% to 25%. What condition is this a sign of?

A. Normal conditions
B. Start-up conditions
C. Nocardia filaments
D. Old sludge (long SRT) (low F/M)

Answer: The answer to the question is A. Being able to interpret the visual conditions of an activated sludge facility is vital for the successful operations. A thin, light-tan foam is normal conditions. Start-up is normally a thick white billowy foam, while Nocardia is normally viewed as a thick, greasy and dark tan. Old sludge is usually thick, scummy and dark-brown foam. Knowing these conditions will help the operator troubleshoot and operate the activated sludge facility efficiently and professionally.

Water Treatment Sample Question

What is the recommended location for a newly installed service line?

A. 45 degrees up from the bottom of the main
B. At the bottom of the main 
C. At the top of the main
D. 45 degrees down from the top of the main

Answer: The correct answer is D. Tapping a water distribution main 45 degrees from the top helps eliminate any accumulated trapped air in the top portion of the main and any accumulated sediment in the bottom portion of the main from entering the service line. It is also important to install service lines below the deepest anticipated frost lines for that area and to provide a means of slack by laying the line in a downward S-curve formation from the tap. 

About the authors: Rick Lallish is the Water Pollution Control program director at the Environmental Resources Training Center (ERTC) 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.


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