Wastewater Operator Class C Exam Practice Review with Questions and Answers
– 100% Solved
A colored dye solution is added into the raw wastewater entering a primary settling tank. The
dye color was noticeable in the effluent in 15 min and all of the color had passed through the
tank in 40 min. What does this indicate?
A. Wastewater is passing through the tank too fast for effective settling
B. Optimal detention time is being achieved
C. This tank has a detention time of 40 min.
D. This tank design has a detention time of 55 min. - ✔✔✔-A. Wastewater is passing through
the tank too fast for effective settling
A decrease in temperature will have what effect on disinfection?
A. Require longer contact time
B. Require shorter contact time
C. Increase rate of disinfection
D. Have no effect on disinfection - ✔✔✔-A. Require longer contact time
A good settling sludge would consist of what type of protozoa?
A. Rotifers and nematodes
B. Amoebas and Flagellates
C. Stalked ciliates and mastagoria
D. Free swimmers and stalk ciliates - ✔✔✔-D. Free swimmers and stalk ciliates
A plant with a flow of 1 MGD should be monitored
,Wastewater Operator Class C Exam Practice Review with Questions and Answers
– 100% Solved
A. Continuously
B. Intermittently
C. Daily
D. Every four hours depending on surface load - ✔✔✔-A. Continuously
According to FAC Ch. 62-600, Domestic WasteWater Facilities, your job s an operator during
major process breakdowns is to?
A. Maintain competent documentation and record keeping
B. Report to the DEP within 24 hours after the problem is fixed
C. Call the fire department
D. Shut down the plant immediately - ✔✔✔-A. Maintain competent documentation and record
keeping
After removing the roof of the chlorinator storage, building during the summer, the Cl2 stop
feeding, what is the cause?
A. The CPRV became clogged
B. The tank got hotter than the manifold
C. The external pressure reducer failed
D. The tank is empty - ✔✔✔-B. The tank got hotter than the manifold
Amperometric titration is used to measure
A. Dissolved solids
B. Chlorine residual
, Wastewater Operator Class C Exam Practice Review with Questions and Answers
– 100% Solved
C. Colloids
D. Emulsions - ✔✔✔-B. Chlorine residual
As an operator, how do you control the anaerobic digestion process?
A. Microbial population and temperature
B. H2S and methane concentration
C. Temperature and rate of raw sludge feed
D. Methane and Co2 production - ✔✔✔-C. Temperature and rate of raw sludge feed
At what pH would disinfection be at its greatest?
A. 9
B. 7
C. 6.5
D. 5 - ✔✔✔-D. 5
Before operating any piece of equipment what should be done?
A. Lock out Tag out (remember, safety first!)
B. Read O & M manual
C. Read manufacturers manual
D. Notify supervisor - ✔✔✔-C. Read manufacturers manual
Cathodic protection is used for what purpose?
– 100% Solved
A colored dye solution is added into the raw wastewater entering a primary settling tank. The
dye color was noticeable in the effluent in 15 min and all of the color had passed through the
tank in 40 min. What does this indicate?
A. Wastewater is passing through the tank too fast for effective settling
B. Optimal detention time is being achieved
C. This tank has a detention time of 40 min.
D. This tank design has a detention time of 55 min. - ✔✔✔-A. Wastewater is passing through
the tank too fast for effective settling
A decrease in temperature will have what effect on disinfection?
A. Require longer contact time
B. Require shorter contact time
C. Increase rate of disinfection
D. Have no effect on disinfection - ✔✔✔-A. Require longer contact time
A good settling sludge would consist of what type of protozoa?
A. Rotifers and nematodes
B. Amoebas and Flagellates
C. Stalked ciliates and mastagoria
D. Free swimmers and stalk ciliates - ✔✔✔-D. Free swimmers and stalk ciliates
A plant with a flow of 1 MGD should be monitored
,Wastewater Operator Class C Exam Practice Review with Questions and Answers
– 100% Solved
A. Continuously
B. Intermittently
C. Daily
D. Every four hours depending on surface load - ✔✔✔-A. Continuously
According to FAC Ch. 62-600, Domestic WasteWater Facilities, your job s an operator during
major process breakdowns is to?
A. Maintain competent documentation and record keeping
B. Report to the DEP within 24 hours after the problem is fixed
C. Call the fire department
D. Shut down the plant immediately - ✔✔✔-A. Maintain competent documentation and record
keeping
After removing the roof of the chlorinator storage, building during the summer, the Cl2 stop
feeding, what is the cause?
A. The CPRV became clogged
B. The tank got hotter than the manifold
C. The external pressure reducer failed
D. The tank is empty - ✔✔✔-B. The tank got hotter than the manifold
Amperometric titration is used to measure
A. Dissolved solids
B. Chlorine residual
, Wastewater Operator Class C Exam Practice Review with Questions and Answers
– 100% Solved
C. Colloids
D. Emulsions - ✔✔✔-B. Chlorine residual
As an operator, how do you control the anaerobic digestion process?
A. Microbial population and temperature
B. H2S and methane concentration
C. Temperature and rate of raw sludge feed
D. Methane and Co2 production - ✔✔✔-C. Temperature and rate of raw sludge feed
At what pH would disinfection be at its greatest?
A. 9
B. 7
C. 6.5
D. 5 - ✔✔✔-D. 5
Before operating any piece of equipment what should be done?
A. Lock out Tag out (remember, safety first!)
B. Read O & M manual
C. Read manufacturers manual
D. Notify supervisor - ✔✔✔-C. Read manufacturers manual
Cathodic protection is used for what purpose?
