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WasteWater Operator class C exam practice review Questions
with 100% Verified Answers UPDATED!!!
When Chlorine is combined with water what type of pipe
should be used?
A. Ductile iron
B. Asbestos concrete
C. PVC
D. Carbon Steel - ANSWER C. PVC
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 - ANSWER D. Free swimmers
and stalk ciliates
What is Phenolphylein used for in titration
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A. Oxidizer
B. Indicator
C. Acid reducer to lower pH
D. Applicator - ANSWER B. Indicator
Your plant has an influent of 220 BOD and 163 TSS, and an
effluent of 10 BOD, and 6 TSS. What is the BOD removal
efficiency in your plant?
A. 92%
B. 94%
C. 95%
D. 96% - ANSWER C. 95%
You suspect your anaerobic digester is going sour. What is the
best way to verify its condition?
A. pH
B. Foam type
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C. VA/ALK ratio
D. DO - ANSWER C. VA/ALK ratio
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 - ANSWER C. Read manufacturers manual
Detritus is noticed in your grit channel. What is the problem?
A. Velocity too fast with short D/T
B. Velocity too low with long D/T
C. Short circuiting
D. Density currents - ANSWER B. Velocity too low with long D/T
What is considered normal operation of an aerobic digester?
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A. Fill react
B. Skim off foam when needed
C. Settle and Decant as needed
D. Feed only during low flow or constant when the sun is out -
ANSWER C. Settle and Decant as needed
A plant with a flow of 1 MGD should be monitored
A. Continuously
B. Intermittently
C. Daily
D. Every four hours depending on surface load - ANSWER A.
Continuously
What do total solids consist of?
A. Dissolved and settleable
B. Floatable and settlable
C. Suspended and dissolved
WasteWater Operator class C exam practice review Questions
with 100% Verified Answers UPDATED!!!
When Chlorine is combined with water what type of pipe
should be used?
A. Ductile iron
B. Asbestos concrete
C. PVC
D. Carbon Steel - ANSWER C. PVC
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 - ANSWER D. Free swimmers
and stalk ciliates
What is Phenolphylein used for in titration
,2|Page
A. Oxidizer
B. Indicator
C. Acid reducer to lower pH
D. Applicator - ANSWER B. Indicator
Your plant has an influent of 220 BOD and 163 TSS, and an
effluent of 10 BOD, and 6 TSS. What is the BOD removal
efficiency in your plant?
A. 92%
B. 94%
C. 95%
D. 96% - ANSWER C. 95%
You suspect your anaerobic digester is going sour. What is the
best way to verify its condition?
A. pH
B. Foam type
,3|Page
C. VA/ALK ratio
D. DO - ANSWER C. VA/ALK ratio
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 - ANSWER C. Read manufacturers manual
Detritus is noticed in your grit channel. What is the problem?
A. Velocity too fast with short D/T
B. Velocity too low with long D/T
C. Short circuiting
D. Density currents - ANSWER B. Velocity too low with long D/T
What is considered normal operation of an aerobic digester?
, 4|Page
A. Fill react
B. Skim off foam when needed
C. Settle and Decant as needed
D. Feed only during low flow or constant when the sun is out -
ANSWER C. Settle and Decant as needed
A plant with a flow of 1 MGD should be monitored
A. Continuously
B. Intermittently
C. Daily
D. Every four hours depending on surface load - ANSWER A.
Continuously
What do total solids consist of?
A. Dissolved and settleable
B. Floatable and settlable
C. Suspended and dissolved
