Basic Wastewater Operator Practice Exam Test with Answers Rated A
What is the predominant organism in a healthy activated
sludge treatment plant?
A. Stalked ciliates A. Stalked Ciliates
B. rotifers
C. nematodes
D. amoebas
A composite sample must be?
A. sporadically collected in the treatment plant
D. representative and sub-samples time spaced over 15
B. taken at one time
minutes apart
C. analyzed immediately
D. representative and sub-samples time spaced over 15
minutes apart
What is the standard volume for a BOD sample bottle?
A. 150 mL
c. 300 mL
B. 200 mL
C. 300 mL
D. 500 mL
If you have a lime slurry feed line, what is the best valve to
use?
A. plug valve A. plug valve
B. butterfly valve
C. RPZ dual check valve
D. gate valve
5. If you notice a predominance of rotifers in your activat-
ed sludge sample while looking at it under a microscope,
C. old sludge
what does this indicate?
, Basic Wastewater Operator Practice Exam Test with Answers Rated A
A. healthy sludge
B. young sludge
C. old sludge
D. middle age sludge
Calculate the BOD using the given information:
Initial DO: 8.3
Final DO: 5.9
Milliliters of sample used: 2
a. 360 mg/L
a. 360 mg/L
b. 210 mg/L
c. 856 mg/L
d. 36 mg/L
If your activated sludge plant begins to nitrify, what con-
ditions would you expect to decrease?
A. settling in clarifiers a. settling in the clarifiers
B. chlorine demand
C. BOD effluent
D. TSS in effluent
How do you calibrate a chemical feed pump?
A. by measuring the pump output
A. by measuring the pump output
B. using the SWAG method
C. jar test
D. with a microscope
What is the chemical formula for sulfuric acid?
d. H2SO4
a. HNO3
b. HCl
, Basic Wastewater Operator Practice Exam Test with Answers Rated A
c. NaOH
d. H2SO4
What is the most common type of activated sludge pack-
age plants?
a. extended aeration a. extended aeration
b. sequential batch reactor
c. oxidation ditch
d. bardenpho
What is the most appropriate method of reducing the F:M
ratio?
A. increase wasting b. decrease wasting
b. decrease wasting
c. reduce BOD from influent flow
D. add polymer to RAS to increase settling
An operator notices a portion of the aeration tank with
large bubbles rising up. What is the most likely problem?
a. equal air distribution
b. unequal air distribution caused by a blown dittuser
b. unequal air distribution caused by a blown/clogged
dittuser
c. normal operation
d. reason to believe the air filter in the blower is clogged
What is suction lift?
a. a team approach to lifting heavy objects
b. the pressure on the suction side of the pump
b. the pressure on the suction side of the pump
c. the measurement of liquid pressure at the pump
d. the measure of how bad your workers lift heavy objects
What is the predominant organism in a healthy activated
sludge treatment plant?
A. Stalked ciliates A. Stalked Ciliates
B. rotifers
C. nematodes
D. amoebas
A composite sample must be?
A. sporadically collected in the treatment plant
D. representative and sub-samples time spaced over 15
B. taken at one time
minutes apart
C. analyzed immediately
D. representative and sub-samples time spaced over 15
minutes apart
What is the standard volume for a BOD sample bottle?
A. 150 mL
c. 300 mL
B. 200 mL
C. 300 mL
D. 500 mL
If you have a lime slurry feed line, what is the best valve to
use?
A. plug valve A. plug valve
B. butterfly valve
C. RPZ dual check valve
D. gate valve
5. If you notice a predominance of rotifers in your activat-
ed sludge sample while looking at it under a microscope,
C. old sludge
what does this indicate?
, Basic Wastewater Operator Practice Exam Test with Answers Rated A
A. healthy sludge
B. young sludge
C. old sludge
D. middle age sludge
Calculate the BOD using the given information:
Initial DO: 8.3
Final DO: 5.9
Milliliters of sample used: 2
a. 360 mg/L
a. 360 mg/L
b. 210 mg/L
c. 856 mg/L
d. 36 mg/L
If your activated sludge plant begins to nitrify, what con-
ditions would you expect to decrease?
A. settling in clarifiers a. settling in the clarifiers
B. chlorine demand
C. BOD effluent
D. TSS in effluent
How do you calibrate a chemical feed pump?
A. by measuring the pump output
A. by measuring the pump output
B. using the SWAG method
C. jar test
D. with a microscope
What is the chemical formula for sulfuric acid?
d. H2SO4
a. HNO3
b. HCl
, Basic Wastewater Operator Practice Exam Test with Answers Rated A
c. NaOH
d. H2SO4
What is the most common type of activated sludge pack-
age plants?
a. extended aeration a. extended aeration
b. sequential batch reactor
c. oxidation ditch
d. bardenpho
What is the most appropriate method of reducing the F:M
ratio?
A. increase wasting b. decrease wasting
b. decrease wasting
c. reduce BOD from influent flow
D. add polymer to RAS to increase settling
An operator notices a portion of the aeration tank with
large bubbles rising up. What is the most likely problem?
a. equal air distribution
b. unequal air distribution caused by a blown dittuser
b. unequal air distribution caused by a blown/clogged
dittuser
c. normal operation
d. reason to believe the air filter in the blower is clogged
What is suction lift?
a. a team approach to lifting heavy objects
b. the pressure on the suction side of the pump
b. the pressure on the suction side of the pump
c. the measurement of liquid pressure at the pump
d. the measure of how bad your workers lift heavy objects
