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Nevada Wastewater Treatment Plant Operator Grade II
Exam ACTUAL Exam ALL 200 QUESTIONS AND CORRECT
ANSWERS LATEST UPDATE THIS YEAR
Nevada Wastewater Treatment Plant Operator Grade II Exam
Comprehensive Exam Coverage Areas (Applies to All Batches)
The full exam practice series covers the following core competency domains required for
Nevada Grade II Wastewater Treatment Plant Operators:
1. Preliminary & Primary Treatment Processes
2. Secondary (Biological) Treatment Systems
3. Advanced & Tertiary Treatment
4. Disinfection Methods & Effluent Standards
5. Sludge (Biosolids) Treatment & Handling
6. Laboratory Testing & Process Control Calculations
7. Activated Sludge Process Control
8. Nutrient Removal (Nitrogen & Phosphorus)
9. Hydraulics & Flow Measurement
10. Pumps, Motors & Mechanical Equipment
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11. Safety & OSHA Regulations
12. Confined Space & Hazardous Gas Safety
13. Regulatory Compliance (NPDES & Nevada Regulations)
14. Collection Systems & Lift Stations
15. Troubleshooting Operational Problems
16. Instrumentation & Process Monitoring
BATCH 1 – 50 Practice Questions (With Verified Answers & Rationales)
1. What is the primary objective of screening in wastewater treatment?
A. Remove dissolved solids
B. Remove large debris
C. Remove pathogens
D. Reduce BOD
Correct Answer: B
Rationale: Screening removes large debris such as rags, sticks, and plastics to protect
downstream equipment.
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2. Grit chambers are designed to remove:
A. Dissolved organics
B. Suspended solids
C. Inorganic sand and gravel
D. Bacteria
Correct Answer: C
Rationale: Grit chambers remove heavy inorganic particles like sand and gravel to prevent
abrasion of pumps.
3. Hydraulic detention time is best defined as:
A. Time required for sludge digestion
B. Time wastewater remains in a tank
C. Pump run time
D. Chlorine contact time
Correct Answer: B
Rationale: Detention time refers to how long wastewater stays in a treatment unit.
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4. The purpose of return activated sludge (RAS) is to:
A. Waste excess sludge
B. Increase oxygen
C. Maintain microorganism concentration
D. Remove grit
Correct Answer: C
Rationale: RAS returns microorganisms to the aeration tank to maintain MLSS concentration.
5. High sludge volume index (SVI) indicates:
A. Good settling
B. Bulking sludge
C. Low MLSS
D. Proper digestion
Correct Answer: B
Rationale: High SVI suggests poor settling and potential filamentous bulking.
6. The primary purpose of aeration is to:
4
Nevada Wastewater Treatment Plant Operator Grade II
Exam ACTUAL Exam ALL 200 QUESTIONS AND CORRECT
ANSWERS LATEST UPDATE THIS YEAR
Nevada Wastewater Treatment Plant Operator Grade II Exam
Comprehensive Exam Coverage Areas (Applies to All Batches)
The full exam practice series covers the following core competency domains required for
Nevada Grade II Wastewater Treatment Plant Operators:
1. Preliminary & Primary Treatment Processes
2. Secondary (Biological) Treatment Systems
3. Advanced & Tertiary Treatment
4. Disinfection Methods & Effluent Standards
5. Sludge (Biosolids) Treatment & Handling
6. Laboratory Testing & Process Control Calculations
7. Activated Sludge Process Control
8. Nutrient Removal (Nitrogen & Phosphorus)
9. Hydraulics & Flow Measurement
10. Pumps, Motors & Mechanical Equipment
1
, Page 2 of 85
11. Safety & OSHA Regulations
12. Confined Space & Hazardous Gas Safety
13. Regulatory Compliance (NPDES & Nevada Regulations)
14. Collection Systems & Lift Stations
15. Troubleshooting Operational Problems
16. Instrumentation & Process Monitoring
BATCH 1 – 50 Practice Questions (With Verified Answers & Rationales)
1. What is the primary objective of screening in wastewater treatment?
A. Remove dissolved solids
B. Remove large debris
C. Remove pathogens
D. Reduce BOD
Correct Answer: B
Rationale: Screening removes large debris such as rags, sticks, and plastics to protect
downstream equipment.
2
, Page 3 of 85
2. Grit chambers are designed to remove:
A. Dissolved organics
B. Suspended solids
C. Inorganic sand and gravel
D. Bacteria
Correct Answer: C
Rationale: Grit chambers remove heavy inorganic particles like sand and gravel to prevent
abrasion of pumps.
3. Hydraulic detention time is best defined as:
A. Time required for sludge digestion
B. Time wastewater remains in a tank
C. Pump run time
D. Chlorine contact time
Correct Answer: B
Rationale: Detention time refers to how long wastewater stays in a treatment unit.
3
, Page 4 of 85
4. The purpose of return activated sludge (RAS) is to:
A. Waste excess sludge
B. Increase oxygen
C. Maintain microorganism concentration
D. Remove grit
Correct Answer: C
Rationale: RAS returns microorganisms to the aeration tank to maintain MLSS concentration.
5. High sludge volume index (SVI) indicates:
A. Good settling
B. Bulking sludge
C. Low MLSS
D. Proper digestion
Correct Answer: B
Rationale: High SVI suggests poor settling and potential filamentous bulking.
6. The primary purpose of aeration is to:
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