Question 1: What are the main sources of domestic sewage in the collection system?
a. Canals
b. Surface flow
c. Ocean outfall
d. Households and commercial establishments
Correct Answer: d
Question 2: Why is it important to maintain a horizontal weir in a clarifier?
a. Prevent sludge bulking
b. Prevent short-circuiting
c. Prevent gasification
d. Prevent excessive slime growth
Correct Answer: b
Question 3: What are mostly removed in the grit channel?
a. Biomass
b. Organics
c. Dissolved solids
d. Sand- eggshells- cinders- and heavier particulate matter
Correct Answer: d
Question 4: How often should an anaerobic digester be fed?
a. Several times a day
b. Once a day
c. Twice a week
d. Five times per week
Correct Answer: a
Question 5: What is the health effect of carbon dioxide?
a. Vomiting
b. Migraine
c. Can lead to asphyxiation
d. Rapid heart beat
Correct Answer: c
Question 6: Which of the following enters the headworks of a treatment plant?
a. Effluent
b. Supernatant
c. WAS
d. Influent
Correct Answer: d
Question 7: Which gas diminishes your sense of smell?
a. Hydrogen
b. Hydrogen sulfide
c. Nitrogen
d. Ethane
Correct Answer: b
Question 8: What type of microorganism can use nitrate as a source of oxygen?
a. Aerobic bacteria
b. Anaerobic bacteria
c. Facultative bacteria
d. Zoogleal
Correct Answer: c