1. The dissolved oxygen concentration should normally _ as you proceed through the stages of the RBC system.
c. remain the same
2. Which one of the following is a set of processes, all of which are variations of the conventional activated sludge treatment process?
a. high rate/aerated detrition/extended aeration
b. aerated detrition/extended aeration/contact stabilization
c. extended aeration/contact stabilization/tertiary treatment
d. high rate/extended aeration/contact stabilization
e. aerated detrition/contact stabilization/waste stabilization pond
3. Your maintenance person wants to use general purpose grease in the RBC bearings. The reason for not using geral purpose grease is _.
a. it does not contain a high load capability or moisture inhibitor
b. the temperature rating is too low
c. the color will not show a rusting condition
d. the RBC speed is not right for general purpose grease
4. The function of trickling filter or bio disc is to _.
a. remove large objects and debris
b. remove nitrates and chlorides
c. remove pH for final clarification
d. remove BOD
5. The purpose of algae in a sewage lagoon is to _.
a. eat the harmful bacteria
b. replenish dissolved oxygen in the water
c. fix nitrogen from the air