Wastewater Grade 4 Exam UPDATED
ACTUAL QUESTIONS AND CORRECT
ANSWERS
After making a change in the operation of a biological treatment process, how long does it
take to properly evaluate whether the change was beneficial? - CORRECT
ANSWER Two to three times the MCRT
What is affected first when the anaerobic digestion process is starting to deteriorate? -
CORRECT ANSWER Volatile Acids/Alkalinity ratio
In certain situation, a supervisor encourages the employees to make their own decision.
This is considered to be: - CORRECT ANSWER Highly desirable because it
encourages employee growth and frees the supervisor for other tasks
Generally, as an individual progresses upward in management, reliance on personal technical
skill: - CORRECT ANSWER decrease
The BOD in an aeration tank is oxidized in what order? - CORRECT
ANSWER Carbonaceous then nitrogenous
If a pre-aerated grit chamber is aerated above design guidelines, the following will occur: -
CORRECT ANSWER Less accumulation of organics in the grit
The purpose of adding sodium thiosulfate to a microbiological (such as fecal coliform)
sample bottles is to: - CORRECT ANSWER Remove any chlorine residual present
Job specifications refer to: - CORRECT ANSWER The principal duties and functions
of various jobs
, What is the purpose of returned activated sludge (RAS)? - CORRECT ANSWER To
keep a biological population and re-aerate the microorganisms
Under which one of the following conditions should sludge wasting normally be increased? -
CORRECT ANSWER A dark brown scummy foam appears on the aeration tank
surface
During the past month at your plant the SVI has continually decreased. The suspended solids
in the effluent are increasing and the CBOD of the effluent is below 10 mg/L. What should
you do? - CORRECT ANSWER Increase WAS
Which of the following causes the greatest friction loss in a pipe? - CORRECT
ANSWER Increasing the velocity of wastewater
What microscopic organisms will be found in a stable activated sludge process? - CORRECT
ANSWER Free swimming and stalked ciliates and rotifers
The ash content is the same as which of the following? - CORRECT
ANSWER inorganic solids
What is the purpose of zoogleal mass on a fixed growth secondary process? - CORRECT
ANSWER To oxidize the BOD
What are the end products of the aerobic biochemical reaction? - CORRECT
ANSWER H2O and CO2
How can you tell if a new pump delivering design flows and pressures? - CORRECT
ANSWER Measure the flows and pressures and compare with manufacture's pump
curve
Pump packing should be: - CORRECT ANSWER Tightened down to a drip
ACTUAL QUESTIONS AND CORRECT
ANSWERS
After making a change in the operation of a biological treatment process, how long does it
take to properly evaluate whether the change was beneficial? - CORRECT
ANSWER Two to three times the MCRT
What is affected first when the anaerobic digestion process is starting to deteriorate? -
CORRECT ANSWER Volatile Acids/Alkalinity ratio
In certain situation, a supervisor encourages the employees to make their own decision.
This is considered to be: - CORRECT ANSWER Highly desirable because it
encourages employee growth and frees the supervisor for other tasks
Generally, as an individual progresses upward in management, reliance on personal technical
skill: - CORRECT ANSWER decrease
The BOD in an aeration tank is oxidized in what order? - CORRECT
ANSWER Carbonaceous then nitrogenous
If a pre-aerated grit chamber is aerated above design guidelines, the following will occur: -
CORRECT ANSWER Less accumulation of organics in the grit
The purpose of adding sodium thiosulfate to a microbiological (such as fecal coliform)
sample bottles is to: - CORRECT ANSWER Remove any chlorine residual present
Job specifications refer to: - CORRECT ANSWER The principal duties and functions
of various jobs
, What is the purpose of returned activated sludge (RAS)? - CORRECT ANSWER To
keep a biological population and re-aerate the microorganisms
Under which one of the following conditions should sludge wasting normally be increased? -
CORRECT ANSWER A dark brown scummy foam appears on the aeration tank
surface
During the past month at your plant the SVI has continually decreased. The suspended solids
in the effluent are increasing and the CBOD of the effluent is below 10 mg/L. What should
you do? - CORRECT ANSWER Increase WAS
Which of the following causes the greatest friction loss in a pipe? - CORRECT
ANSWER Increasing the velocity of wastewater
What microscopic organisms will be found in a stable activated sludge process? - CORRECT
ANSWER Free swimming and stalked ciliates and rotifers
The ash content is the same as which of the following? - CORRECT
ANSWER inorganic solids
What is the purpose of zoogleal mass on a fixed growth secondary process? - CORRECT
ANSWER To oxidize the BOD
What are the end products of the aerobic biochemical reaction? - CORRECT
ANSWER H2O and CO2
How can you tell if a new pump delivering design flows and pressures? - CORRECT
ANSWER Measure the flows and pressures and compare with manufacture's pump
curve
Pump packing should be: - CORRECT ANSWER Tightened down to a drip
