Ca Grade 2 Wastewater Treatment Operator
Practice Exam 1 Questions and Answers
Question 1
If a primary clarifier is placed out of service, then how should a plant with at least 2
trickling filters operate the system?
Correct Answer
operate the filters in series
Question 2
What are the main sources of domestic sewage in the collection system?
Correct Answer
household and commercial establishments
Question 3
The best way to evaluate the effluent TSS concentration from a plant is to:
Correct Answer
check the composite sample of TSS
Question 4
What should be scheduled every 3 months for a flamer arrester in an anaerobic
digester?
Correct Answer
maintenance
Page 1 of 16
,Question 5
What does black sludge at the bottom of a secondary clarifier located downstream of
a trickling filter signify?
Correct Answer
sludge has stayed in the secondary clarifier too long
Question 6
How does an activated sludge system remove watse from wastewater?
Correct Answer
biological treatment
Question 7
What is the equivalent of 1 mg/l?
Correct Answer
1 ppm
Question 8
In general, how will warmer temp affect the settling rate of solids in a clarifer?
Correct Answer
Increase the settling rate
Question 9
Which of the following is not true about hydrogen sulfide?
Correct Answer
hydrogen sulfide is lighter than air
Question 10
Which of the following is true about COD and BOD?
Correct Answer
they are indirect measurements of the organic content in the influent
Page 2 of 16
, Question 11
What is a common way to determine the organic strength of wastes in the influent?
Correct Answer
test for the biochemical oxygen demand
Question 12
Which is true about the temperature in an anaerobic digester?
Correct Answer
Temperature in a digester should not be changed by more than 1 degree Fahrenheit
per day
Question 13
What is the recirculation ratio for a trickling filter?
Correct Answer
Qr/Q
Question 14
An increase in the acid/alkalinity ratio for an anaerobic digester means:
Correct Answer
Acid concentration is increasing or alkalinity is decreasing
Question 15
How will algae impact the chlorine demand in the pond effluent?
Correct Answer
increase the chlorine demand
Page 3 of 16
Practice Exam 1 Questions and Answers
Question 1
If a primary clarifier is placed out of service, then how should a plant with at least 2
trickling filters operate the system?
Correct Answer
operate the filters in series
Question 2
What are the main sources of domestic sewage in the collection system?
Correct Answer
household and commercial establishments
Question 3
The best way to evaluate the effluent TSS concentration from a plant is to:
Correct Answer
check the composite sample of TSS
Question 4
What should be scheduled every 3 months for a flamer arrester in an anaerobic
digester?
Correct Answer
maintenance
Page 1 of 16
,Question 5
What does black sludge at the bottom of a secondary clarifier located downstream of
a trickling filter signify?
Correct Answer
sludge has stayed in the secondary clarifier too long
Question 6
How does an activated sludge system remove watse from wastewater?
Correct Answer
biological treatment
Question 7
What is the equivalent of 1 mg/l?
Correct Answer
1 ppm
Question 8
In general, how will warmer temp affect the settling rate of solids in a clarifer?
Correct Answer
Increase the settling rate
Question 9
Which of the following is not true about hydrogen sulfide?
Correct Answer
hydrogen sulfide is lighter than air
Question 10
Which of the following is true about COD and BOD?
Correct Answer
they are indirect measurements of the organic content in the influent
Page 2 of 16
, Question 11
What is a common way to determine the organic strength of wastes in the influent?
Correct Answer
test for the biochemical oxygen demand
Question 12
Which is true about the temperature in an anaerobic digester?
Correct Answer
Temperature in a digester should not be changed by more than 1 degree Fahrenheit
per day
Question 13
What is the recirculation ratio for a trickling filter?
Correct Answer
Qr/Q
Question 14
An increase in the acid/alkalinity ratio for an anaerobic digester means:
Correct Answer
Acid concentration is increasing or alkalinity is decreasing
Question 15
How will algae impact the chlorine demand in the pond effluent?
Correct Answer
increase the chlorine demand
Page 3 of 16
