TEXAS WASTEWATER OPERATOR LICENSE VERSION A COMPLETE EXAM
QUESTIONS AND CORRECT ANSWERS RECENTLY UPDATED PASS
GUARANTEE 2026/2027
1. What is the primary purpose of a wastewater treatment plant?
A) Generate electricity
B) Remove contaminants from water before discharge
C) Store industrial chemicals
D) Produce drinking water
2. BOD stands for:
A) Biological Oxygen Demand
B) Basic Organic Density
C) Buffered Oxygen Distribution
D) Bacterial Output Demand
3. COD stands for:
A) Chemical Oxygen Density
B) Chemical Oxygen Demand
C) Calculated Output Discharge
D) Carbon Organic Demand
4. TSS stands for:
A) Total Suspended Solids
B) Toxic Sludge Substance
C) Total Sewer Solids
D) Tertiary Solids System
,5. What does DO stand for in wastewater treatment?
A) Daily Output
B) Dissolved Oxygen
C) Discharge Order
D) Density of Organisms
6. The pH scale ranges from:
A) 0 to 7
B) 0 to 14
C) 1 to 12
D) 1 to 10
7. Neutral pH is:
A) 6
B) 7
C) 8
D) 9
8. Wastewater with a pH below 7 is considered:
A) Neutral
B) Basic
C) Acidic
D) Alkaline
9. Which of the following is a primary treatment process?
A) Activated sludge
B) Sedimentation
C) Chlorination
D) Nitrification
10. Secondary treatment primarily targets:
A) Grit removal
, B) Dissolved and colloidal organics
C) Heavy metals
D) Sludge drying
11. Tertiary treatment is also known as:
A) Primary treatment
B) Secondary treatment
C) Advanced treatment
D) Preliminary treatment
12. Which gas is commonly produced during anaerobic digestion?
A) Oxygen
B) Methane
C) Nitrogen
D) Carbon monoxide
13. Effluent refers to:
A) Incoming wastewater
B) Treated water leaving the plant
C) Sludge removed from clarifiers
D) Chemical dosing solution
14. Influent refers to:
A) Treated discharge
B) Sludge from digestion
C) Raw wastewater entering the plant
D) Return activated sludge
15. Pathogens in wastewater include:
A) Bacteria, viruses, and protozoa
B) Nitrogen and phosphorus only
C) Suspended solids and BOD
D) Grit and screenings
, 16. Fecal coliform is used as an indicator of:
A) Heavy metal contamination
B) Pathogenic contamination
C) Nutrient levels
D) Dissolved oxygen levels
17. Which nutrient is most associated with eutrophication?
A) Iron
B) Phosphorus and nitrogen
C) Calcium
D) Magnesium
18. Eutrophication in receiving waters is caused by:
A) Excessive DO
B) Excessive nutrients promoting algal growth
C) High chlorine levels
D) Low BOD
19. Biosolids are:
A) Industrial waste chemicals
B) Treated sewage sludge
C) Grit and screenings
D) Stormwater runoff
20. Class A biosolids can be used for:
A) Unrestricted land application
B) Industrial disposal only
C) Deep well injection
D) Ocean disposal
21. The term 'point source pollution' refers to:
QUESTIONS AND CORRECT ANSWERS RECENTLY UPDATED PASS
GUARANTEE 2026/2027
1. What is the primary purpose of a wastewater treatment plant?
A) Generate electricity
B) Remove contaminants from water before discharge
C) Store industrial chemicals
D) Produce drinking water
2. BOD stands for:
A) Biological Oxygen Demand
B) Basic Organic Density
C) Buffered Oxygen Distribution
D) Bacterial Output Demand
3. COD stands for:
A) Chemical Oxygen Density
B) Chemical Oxygen Demand
C) Calculated Output Discharge
D) Carbon Organic Demand
4. TSS stands for:
A) Total Suspended Solids
B) Toxic Sludge Substance
C) Total Sewer Solids
D) Tertiary Solids System
,5. What does DO stand for in wastewater treatment?
A) Daily Output
B) Dissolved Oxygen
C) Discharge Order
D) Density of Organisms
6. The pH scale ranges from:
A) 0 to 7
B) 0 to 14
C) 1 to 12
D) 1 to 10
7. Neutral pH is:
A) 6
B) 7
C) 8
D) 9
8. Wastewater with a pH below 7 is considered:
A) Neutral
B) Basic
C) Acidic
D) Alkaline
9. Which of the following is a primary treatment process?
A) Activated sludge
B) Sedimentation
C) Chlorination
D) Nitrification
10. Secondary treatment primarily targets:
A) Grit removal
, B) Dissolved and colloidal organics
C) Heavy metals
D) Sludge drying
11. Tertiary treatment is also known as:
A) Primary treatment
B) Secondary treatment
C) Advanced treatment
D) Preliminary treatment
12. Which gas is commonly produced during anaerobic digestion?
A) Oxygen
B) Methane
C) Nitrogen
D) Carbon monoxide
13. Effluent refers to:
A) Incoming wastewater
B) Treated water leaving the plant
C) Sludge removed from clarifiers
D) Chemical dosing solution
14. Influent refers to:
A) Treated discharge
B) Sludge from digestion
C) Raw wastewater entering the plant
D) Return activated sludge
15. Pathogens in wastewater include:
A) Bacteria, viruses, and protozoa
B) Nitrogen and phosphorus only
C) Suspended solids and BOD
D) Grit and screenings
, 16. Fecal coliform is used as an indicator of:
A) Heavy metal contamination
B) Pathogenic contamination
C) Nutrient levels
D) Dissolved oxygen levels
17. Which nutrient is most associated with eutrophication?
A) Iron
B) Phosphorus and nitrogen
C) Calcium
D) Magnesium
18. Eutrophication in receiving waters is caused by:
A) Excessive DO
B) Excessive nutrients promoting algal growth
C) High chlorine levels
D) Low BOD
19. Biosolids are:
A) Industrial waste chemicals
B) Treated sewage sludge
C) Grit and screenings
D) Stormwater runoff
20. Class A biosolids can be used for:
A) Unrestricted land application
B) Industrial disposal only
C) Deep well injection
D) Ocean disposal
21. The term 'point source pollution' refers to:
