WASTEWATER TREATMENT OPERATOR CERTIFICATION EXAM
ACTUAL EXAM 200 QUESTIONS AND CORRECT DETAILED
ANSWERS WITH RATIONALES|ALREADY GRADED A
1 mg/l is the same as 1 part per billion (ppb)
True or False - ANSWER: False (v.1 pg 468)
A SCADA system is capable of monitoring and controlling equipment from a remote
location
True or False - ANSWER: True (v.2 pg 627)
A Discharge Monitoring Report is typically submitted to the regulatory agency on a
daily basis
True or False - ANSWER: False
A mechanical seal is used to prevent leaks between the pump casing and shaft.
True or False - ANSWER: True (v.2 pg 356)
Alkalinity is the capacity of a liquid to neutralize a base.
True or False - ANSWER: False (v.2 pg 813)
Typical mixed liquor suspended solids concentration is 1,000 to 4,500 mg/l.
True or False - ANSWER: True (v.2 pg 54)
Turbidity is caused by suspended matters.
True or False - ANSWER: True (v.2 pg 606)
Algae is not essential to the successful operation of both aerobic and facultative
ponds.
True or False - ANSWER: False (v.1 pg 299)
The addition of acid and CO2 will lower the pH of wastewater.
True or False - ANSWER: True (v.1 pg 299)
Hydrogen sulfide will deteriorate concrete structures.
, True or False - ANSWER: True (v.1 pg 20)
The higher the pH, the better the disinfection - ANSWER: False (v.1 pg 352)
Maintain a dissolved oxygen concentration of 12 to 14 mg/l in the aeration tank.
True or False - ANSWER: False (v.2 pg 53)
When the velocity of the wastewater in a clarifier is greater in some sections than
others, it will lead to short-circuiting.
True or False - ANSWER: True (v.1 pg 135)
The F/M ratio will decrease when the microorganism population in the aeration tank
increases.
True or False - ANSWER: True (v.2 pg 16)
Algae growth will be faster when there is less sunlight.
True or False - ANSWER: False (v.1 pg 309)
The higher the temperature, the more rapid the rate of disinfection.
True or False - ANSWER: True (v.1 pg 352)
One of the benefits of recirculation for a trickling filter is that it decreases the
contact time of the wastewater with the biological film.
True or False - ANSWER: False (v.1 pg 175)
Maintaining a constant temperature in an anaerobic digester is one way to prevent
foaming from recurring.
True or False - ANSWER: True (v.2 pg 187)
Preventative maintenance is a proactive, programmed, and systematic approach to
maintenance.
True or False - ANSWER: True (v.2 pg 718)
Abnormal operation in a pond will not occur if it is overloaded with BOD.
True or False - ANSWER: False (v.1 pg 307)
Anaerobic decomposition of sewage will release hydrogen sulfide.
ACTUAL EXAM 200 QUESTIONS AND CORRECT DETAILED
ANSWERS WITH RATIONALES|ALREADY GRADED A
1 mg/l is the same as 1 part per billion (ppb)
True or False - ANSWER: False (v.1 pg 468)
A SCADA system is capable of monitoring and controlling equipment from a remote
location
True or False - ANSWER: True (v.2 pg 627)
A Discharge Monitoring Report is typically submitted to the regulatory agency on a
daily basis
True or False - ANSWER: False
A mechanical seal is used to prevent leaks between the pump casing and shaft.
True or False - ANSWER: True (v.2 pg 356)
Alkalinity is the capacity of a liquid to neutralize a base.
True or False - ANSWER: False (v.2 pg 813)
Typical mixed liquor suspended solids concentration is 1,000 to 4,500 mg/l.
True or False - ANSWER: True (v.2 pg 54)
Turbidity is caused by suspended matters.
True or False - ANSWER: True (v.2 pg 606)
Algae is not essential to the successful operation of both aerobic and facultative
ponds.
True or False - ANSWER: False (v.1 pg 299)
The addition of acid and CO2 will lower the pH of wastewater.
True or False - ANSWER: True (v.1 pg 299)
Hydrogen sulfide will deteriorate concrete structures.
, True or False - ANSWER: True (v.1 pg 20)
The higher the pH, the better the disinfection - ANSWER: False (v.1 pg 352)
Maintain a dissolved oxygen concentration of 12 to 14 mg/l in the aeration tank.
True or False - ANSWER: False (v.2 pg 53)
When the velocity of the wastewater in a clarifier is greater in some sections than
others, it will lead to short-circuiting.
True or False - ANSWER: True (v.1 pg 135)
The F/M ratio will decrease when the microorganism population in the aeration tank
increases.
True or False - ANSWER: True (v.2 pg 16)
Algae growth will be faster when there is less sunlight.
True or False - ANSWER: False (v.1 pg 309)
The higher the temperature, the more rapid the rate of disinfection.
True or False - ANSWER: True (v.1 pg 352)
One of the benefits of recirculation for a trickling filter is that it decreases the
contact time of the wastewater with the biological film.
True or False - ANSWER: False (v.1 pg 175)
Maintaining a constant temperature in an anaerobic digester is one way to prevent
foaming from recurring.
True or False - ANSWER: True (v.2 pg 187)
Preventative maintenance is a proactive, programmed, and systematic approach to
maintenance.
True or False - ANSWER: True (v.2 pg 718)
Abnormal operation in a pond will not occur if it is overloaded with BOD.
True or False - ANSWER: False (v.1 pg 307)
Anaerobic decomposition of sewage will release hydrogen sulfide.
