Kansas Wastewater Operator Class II Exam
Practice Questions And 100% Correct Answers
(Verified) Plus Rationales Latest 2026/2027 |
Graded A+ | Guaranteed Pass!!
1. The primary purpose of a wastewater treatment plant is to:
A. Generate electricity
B. Protect public health and the environment
C. Increase water hardness
D. Reduce turbidity for drinking water
Answer: Protect public health and the environment
Rationale: Wastewater treatment plants remove contaminants to prevent
disease, protect ecosystems, and ensure water quality before discharge.
2. Which of the following is considered a primary treatment process?
A. Trickling filter
B. Activated sludge
C. Sedimentation
D. Chlorination
Answer: Sedimentation
Rationale: Primary treatment involves physical removal of settleable solids
through sedimentation.
,3. Which microorganism is primarily responsible for nitrification in
wastewater treatment?
A. Escherichia coli
B. Streptococcus
C. Nitrosomonas and Nitrobacter
D. Pseudomonas
Answer: Nitrosomonas and Nitrobacter
Rationale: Nitrosomonas converts ammonia to nitrite, and Nitrobacter
converts nitrite to nitrate during nitrification.
5. What is the purpose of sludge thickening?
A. Reduce BOD
B. Decrease water content of sludge
C. Increase nutrient levels
D. Sterilize sludge
Answer: Decrease water content of sludge
Rationale: Thickening reduces sludge volume, making subsequent handling
and treatment more efficient.
6. Which of the following best describes a trickling filter?
A. A chemical disinfection process
B. A primary clarifier
C. A fixed-bed biological treatment system
D. A membrane filtration system
Answer: A fixed-bed biological treatment system
,Rationale: Trickling filters provide a surface for microbial growth to
biologically treat wastewater.
7. TSS in wastewater stands for:
A. Total Salt Solution
B. Total Suspended Solids
C. Total Sulfate Solids
D. Total Soluble Substances
Answer: Total Suspended Solids
Rationale: TSS measures the solid particles suspended in wastewater, which
are removed through sedimentation or filtration.
\
BOD (Biochemical Oxygen Demand) measures:
A. Dissolved oxygen in water
B. The amount of oxygen required by microorganisms to decompose
organic matter
C. Nutrient concentrations
D. pH levels
Answer: The amount of oxygen required by microorganisms to
decompose organic matter
Rationale: BOD quantifies the organic load in wastewater by measuring
oxygen consumption during decomposition.
8. The main function of aeration in an activated sludge system is to:
, A. Settle solids
B. Provide oxygen for microbial growth
C. Remove nitrogen chemically
D. Filter solids
Answer: Provide oxygen for microbial growth
Rationale: Aeration supplies oxygen necessary for aerobic bacteria to
decompose organic matter.
9.
10. Which factor primarily affects sedimentation rates in a clarifier?
A. pH
B. Particle size and density
C. Temperature only
D. Dissolved oxygen
Answer: Particle size and density
Rationale: Heavier and larger particles settle faster, while lighter or smaller
particles may remain suspended.
11. Which of the following is a common cause of foaming in activated
sludge systems?
A. Low pH
B. Filamentous bacteria
C. Excess chlorine
D. High TDS
Answer: Filamentous bacteria
Practice Questions And 100% Correct Answers
(Verified) Plus Rationales Latest 2026/2027 |
Graded A+ | Guaranteed Pass!!
1. The primary purpose of a wastewater treatment plant is to:
A. Generate electricity
B. Protect public health and the environment
C. Increase water hardness
D. Reduce turbidity for drinking water
Answer: Protect public health and the environment
Rationale: Wastewater treatment plants remove contaminants to prevent
disease, protect ecosystems, and ensure water quality before discharge.
2. Which of the following is considered a primary treatment process?
A. Trickling filter
B. Activated sludge
C. Sedimentation
D. Chlorination
Answer: Sedimentation
Rationale: Primary treatment involves physical removal of settleable solids
through sedimentation.
,3. Which microorganism is primarily responsible for nitrification in
wastewater treatment?
A. Escherichia coli
B. Streptococcus
C. Nitrosomonas and Nitrobacter
D. Pseudomonas
Answer: Nitrosomonas and Nitrobacter
Rationale: Nitrosomonas converts ammonia to nitrite, and Nitrobacter
converts nitrite to nitrate during nitrification.
5. What is the purpose of sludge thickening?
A. Reduce BOD
B. Decrease water content of sludge
C. Increase nutrient levels
D. Sterilize sludge
Answer: Decrease water content of sludge
Rationale: Thickening reduces sludge volume, making subsequent handling
and treatment more efficient.
6. Which of the following best describes a trickling filter?
A. A chemical disinfection process
B. A primary clarifier
C. A fixed-bed biological treatment system
D. A membrane filtration system
Answer: A fixed-bed biological treatment system
,Rationale: Trickling filters provide a surface for microbial growth to
biologically treat wastewater.
7. TSS in wastewater stands for:
A. Total Salt Solution
B. Total Suspended Solids
C. Total Sulfate Solids
D. Total Soluble Substances
Answer: Total Suspended Solids
Rationale: TSS measures the solid particles suspended in wastewater, which
are removed through sedimentation or filtration.
\
BOD (Biochemical Oxygen Demand) measures:
A. Dissolved oxygen in water
B. The amount of oxygen required by microorganisms to decompose
organic matter
C. Nutrient concentrations
D. pH levels
Answer: The amount of oxygen required by microorganisms to
decompose organic matter
Rationale: BOD quantifies the organic load in wastewater by measuring
oxygen consumption during decomposition.
8. The main function of aeration in an activated sludge system is to:
, A. Settle solids
B. Provide oxygen for microbial growth
C. Remove nitrogen chemically
D. Filter solids
Answer: Provide oxygen for microbial growth
Rationale: Aeration supplies oxygen necessary for aerobic bacteria to
decompose organic matter.
9.
10. Which factor primarily affects sedimentation rates in a clarifier?
A. pH
B. Particle size and density
C. Temperature only
D. Dissolved oxygen
Answer: Particle size and density
Rationale: Heavier and larger particles settle faster, while lighter or smaller
particles may remain suspended.
11. Which of the following is a common cause of foaming in activated
sludge systems?
A. Low pH
B. Filamentous bacteria
C. Excess chlorine
D. High TDS
Answer: Filamentous bacteria
