When faced with a licensing exam, don't struggle with test anxiety! Use the question below and others from our Exam Study Guide series to properly study and prepare for exam questions. Take a look at this sample wastewater treatment licensing question along with an explanation of the correct answer.

Sample question:

What is the typical rotation speed of a rotating biological contactor (RBC)?

A) .5 to 1.0 rpm

B) 1.0 to 1.6 rpm

C) 2.1 to 2.7 rpm

D) 3.1 to 4.0 rpm

Answer:

The equipment manufacturer’s recommendations should govern the selection of rotating speed of the RBC discs. Typical rotational speeds range from 1.0 to 1.6 rpm. Therefore, the answer is B.

Source: WEF MOP11 21-47

About the author
Ricky 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.