CA Grade 2 Wastewater Treatment Operator
Practice Exam 1 – Questions & A+ Solutions
What is the methane content in a properly operating anaerobic
digester? Correct Answer - 65 to 70% by volume
What will the addition of chlorine gas do to the pH of wastewater?
Correct Answer - decrease the pH
What is the purpose of a Parshall Flume? Correct Answer -
Measure the flow rate
What is the typical removal efficency of settleable solids in a
primary clarifier? Correct Answer - 95 to 99%
Which of the follwing is true about pumoing scum from a primary
clarifier? Correct Answer - scum causes more piping problems
than other substances pumped at a wastewater treatment plant
What might cause thick billows of white sudsy foam in the aeration
tank? Correct Answer - MLSS is too low
What does the M in F/M ratio represent? Correct Answer - The
mixed liquor volatile suspended solids in the aeration tank
In general, how will warmer temp affect the settling rate of solids in
a clarifer? Correct Answer - Increase the settling rate
What could happen if the digester gas is mixed with air(85 to 95%
by volume)? Correct Answer - Cause an explosion
How will algae impact the chlorine demand in the pond effluent?
Correct Answer - increase the chlorine demand
, Which of the following is true about a positive displacement pump?
Correct Answer - it must never be started with the discharge
valve closed
What is true about the F/M ratio? Correct Answer - the volume
of the secondary clarifier is not needed to determine the f/m ratio
Which of the following is one of the basic rules of lab work?
Correct Answer - never pipet hazardous material with your
mouth, even if the pipet has been sterialized
What is the recirculation ratio for a trickling filter? Correct
Answer - Qr/Q
Which of the following is true about COD and BOD? Correct
Answer - they are indirect measurements of the organic content
in the influent
What is the purpose of the grit channel? Correct Answer -
remove heavy inorganic waste
Which of the following is true about the extended aeration process?
Correct Answer - it does not produce as much waste sludge as
other processes
What is the correct formula for solids in raw wastewater? Correct
Answer - Non settleable solids + settleable solids = total
suspended solids
What is freeboard in a waste stabilization pond? Correct Answer -
the vertical distance from normal water surface to the top of the
levee
Practice Exam 1 – Questions & A+ Solutions
What is the methane content in a properly operating anaerobic
digester? Correct Answer - 65 to 70% by volume
What will the addition of chlorine gas do to the pH of wastewater?
Correct Answer - decrease the pH
What is the purpose of a Parshall Flume? Correct Answer -
Measure the flow rate
What is the typical removal efficency of settleable solids in a
primary clarifier? Correct Answer - 95 to 99%
Which of the follwing is true about pumoing scum from a primary
clarifier? Correct Answer - scum causes more piping problems
than other substances pumped at a wastewater treatment plant
What might cause thick billows of white sudsy foam in the aeration
tank? Correct Answer - MLSS is too low
What does the M in F/M ratio represent? Correct Answer - The
mixed liquor volatile suspended solids in the aeration tank
In general, how will warmer temp affect the settling rate of solids in
a clarifer? Correct Answer - Increase the settling rate
What could happen if the digester gas is mixed with air(85 to 95%
by volume)? Correct Answer - Cause an explosion
How will algae impact the chlorine demand in the pond effluent?
Correct Answer - increase the chlorine demand
, Which of the following is true about a positive displacement pump?
Correct Answer - it must never be started with the discharge
valve closed
What is true about the F/M ratio? Correct Answer - the volume
of the secondary clarifier is not needed to determine the f/m ratio
Which of the following is one of the basic rules of lab work?
Correct Answer - never pipet hazardous material with your
mouth, even if the pipet has been sterialized
What is the recirculation ratio for a trickling filter? Correct
Answer - Qr/Q
Which of the following is true about COD and BOD? Correct
Answer - they are indirect measurements of the organic content
in the influent
What is the purpose of the grit channel? Correct Answer -
remove heavy inorganic waste
Which of the following is true about the extended aeration process?
Correct Answer - it does not produce as much waste sludge as
other processes
What is the correct formula for solids in raw wastewater? Correct
Answer - Non settleable solids + settleable solids = total
suspended solids
What is freeboard in a waste stabilization pond? Correct Answer -
the vertical distance from normal water surface to the top of the
levee
