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Basic Wastewater Operator Practice Exam TEST FINAL EXAM
AND PRACTICE EXAM 20262027 BANK 2 VERSIONS
QUESTIONS WITH DETAILED VERIFIED ANSWERS EXAM
QUESTIONS WILL COME FROM HERE (100% CORRECT
ANSWERS A+ GRADED
What is the predominant organism in a healthy activated sludge
treatment plant?
A. Stalked ciliates
B. rotifers
C. nematodes
D. amoebas - ANSWERS--A. Stalked Ciliates
A composite sample must be?
A. sporadically collected in the treatment plant
B. taken at one time
C. analyzed immediately
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D. representative and sub-samples time spaced over 15 minutes apart -
ANSWERS--D. representative and sub-samples time spaced over 15
minutes apart
What is the standard volume for a BOD sample bottle?
A. 150 mL
B. 200 mL
C. 300 mL
D. 500 mL - ANSWERS--c. 300 mL
If you have a lime slurry feed line, what is the best valve to use?
A. plug valve
B. butterfly valve
C. RPZ dual check valve
D. gate valve - ANSWERS--A. plug valve
5. If you notice a predominance of rotifers in your activated sludge
sample while looking at it under a microscope, what does this indicate?
A. healthy sludge
B. young sludge
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C. old sludge
D. middle age sludge - ANSWERS--C. old 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
b. 210 mg/L
c. 856 mg/L
d. 36 mg/L - ANSWERS--a. 360 mg/L
If your activated sludge plant begins to nitrify, what conditions would
you expect to decrease?
A. settling in clarifiers
B. chlorine demand
C. BOD effluent
D. TSS in effluent - ANSWERS--a. settling in the clarifiers
How do you calibrate a chemical feed pump?
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A. by measuring the pump output
B. using the SWAG method
C. jar test
D. with a microscope - ANSWERS--A. by measuring the pump output
What is the chemical formula for sulfuric acid?
a. HNO3
b. HCl
c. NaOH
d. H2SO4 - ANSWERS--d. H2SO4
What is the most common type of activated sludge package plants?
a. extended aeration
b. sequential batch reactor
c. oxidation ditch
d. bardenpho -
What is the most appropriate method of reducing the F:M ratio?
Basic Wastewater Operator Practice Exam TEST FINAL EXAM
AND PRACTICE EXAM 20262027 BANK 2 VERSIONS
QUESTIONS WITH DETAILED VERIFIED ANSWERS EXAM
QUESTIONS WILL COME FROM HERE (100% CORRECT
ANSWERS A+ GRADED
What is the predominant organism in a healthy activated sludge
treatment plant?
A. Stalked ciliates
B. rotifers
C. nematodes
D. amoebas - ANSWERS--A. Stalked Ciliates
A composite sample must be?
A. sporadically collected in the treatment plant
B. taken at one time
C. analyzed immediately
,2|Page
D. representative and sub-samples time spaced over 15 minutes apart -
ANSWERS--D. representative and sub-samples time spaced over 15
minutes apart
What is the standard volume for a BOD sample bottle?
A. 150 mL
B. 200 mL
C. 300 mL
D. 500 mL - ANSWERS--c. 300 mL
If you have a lime slurry feed line, what is the best valve to use?
A. plug valve
B. butterfly valve
C. RPZ dual check valve
D. gate valve - ANSWERS--A. plug valve
5. If you notice a predominance of rotifers in your activated sludge
sample while looking at it under a microscope, what does this indicate?
A. healthy sludge
B. young sludge
,3|Page
C. old sludge
D. middle age sludge - ANSWERS--C. old 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
b. 210 mg/L
c. 856 mg/L
d. 36 mg/L - ANSWERS--a. 360 mg/L
If your activated sludge plant begins to nitrify, what conditions would
you expect to decrease?
A. settling in clarifiers
B. chlorine demand
C. BOD effluent
D. TSS in effluent - ANSWERS--a. settling in the clarifiers
How do you calibrate a chemical feed pump?
, 4|Page
A. by measuring the pump output
B. using the SWAG method
C. jar test
D. with a microscope - ANSWERS--A. by measuring the pump output
What is the chemical formula for sulfuric acid?
a. HNO3
b. HCl
c. NaOH
d. H2SO4 - ANSWERS--d. H2SO4
What is the most common type of activated sludge package plants?
a. extended aeration
b. sequential batch reactor
c. oxidation ditch
d. bardenpho -
What is the most appropriate method of reducing the F:M ratio?
