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 The Purpose of Wasting and Lead and Copper Rule Requirements. This time you can test your knowledge about MPN testing and water distribution service lines.
Wastewater Treatment Sample Question
The MPN (Most Probable Number) method for fecal coliform testing has become one of the most common methods for testing. What is a disadvantage for MPN fecal coliform analysis?
A. Sample toxins are diluted
B. Cannot be analyzed by membrane filtration
C. Difficult to interpret, either by observation or gas emission
D. Results are not very accurate and high probability of false positives
Water Treatment Sample Question
In the distribution of potable water, where is the beginning of the service line located?
A. At the meter
B. At the curb stop
C. At the corporation stop
D. Where the line enters the building
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 (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.
