Texas Wastewater Class D Practice
Exam Newest With Complete
Questions And Correct Detailed
Answers| Brand New Version!2026
2027
1. The primary purpose of wastewater treatment is to:
A. Increase water pressure
B. Remove pollutants before discharge
C. Reuse wastewater for drinking
D. Store wastewater indefinitely
Answer: B. Remove pollutants before discharge
Rationale: Wastewater treatment protects public
health and the environment by removing
contaminants before water is released.
2. Which agency regulates wastewater treatment
facilities in Texas?
A. EPA
B. TCEQ
C. OSHA
D. TWDB
,Answer: B. TCEQ
Rationale: The Texas Commission on Environmental
Quality (TCEQ) oversees wastewater treatment
operations in Texas.
3. What is influent?
A. Treated wastewater
B. Wastewater entering the plant
C. Sludge removed from clarifiers
D. Disinfected effuent
Answer: B. Wastewater entering the plant
Rationale: Influent is raw wastewater flowing into the
treatment facility.
4. What is the main function of bar screens?
A. Remove dissolved solids
B. Remove large debris
C. Kill bacteria
D. Add oxygen
Answer: B. Remove large debris
Rationale: Bar screens protect equipment by removing
rags, sticks, and other large objects.
,5. Grit removal systems are designed to remove:
A. Organic matter
B. Floatable grease
C. Sand and gravel
D. Dissolved oxygen
Answer: C. Sand and gravel
Rationale: Grit chambers prevent abrasion and
clogging by removing heavy inorganic materials.
6. Primary clarification removes mainly:
A. Dissolved solids
B. Settleable solids
C. Bacteria
D. Nutrients
Answer: B. Settleable solids
Rationale: Primary clarifiers allow heavier solids to
settle by gravity.
7. What is sludge?
A. Clear treated water
B. Floating grease
, C. Settled solids from treatment
D. Disinfectant chemical
Answer: C. Settled solids from treatment
Rationale: Sludge consists of solids removed during
wastewater treatment processes.
8. Secondary treatment primarily removes:
A. Large debris
B. Settleable solids
C. Dissolved organic matter
D. Chlorine
Answer: C. Dissolved organic matter
Rationale: Biological treatment breaks down
dissolved and suspended organic material.
9. Which organisms are mainly responsible for
biological treatment?
A. Viruses
B. Protozoa
C. Bacteria
D. Algae
Exam Newest With Complete
Questions And Correct Detailed
Answers| Brand New Version!2026
2027
1. The primary purpose of wastewater treatment is to:
A. Increase water pressure
B. Remove pollutants before discharge
C. Reuse wastewater for drinking
D. Store wastewater indefinitely
Answer: B. Remove pollutants before discharge
Rationale: Wastewater treatment protects public
health and the environment by removing
contaminants before water is released.
2. Which agency regulates wastewater treatment
facilities in Texas?
A. EPA
B. TCEQ
C. OSHA
D. TWDB
,Answer: B. TCEQ
Rationale: The Texas Commission on Environmental
Quality (TCEQ) oversees wastewater treatment
operations in Texas.
3. What is influent?
A. Treated wastewater
B. Wastewater entering the plant
C. Sludge removed from clarifiers
D. Disinfected effuent
Answer: B. Wastewater entering the plant
Rationale: Influent is raw wastewater flowing into the
treatment facility.
4. What is the main function of bar screens?
A. Remove dissolved solids
B. Remove large debris
C. Kill bacteria
D. Add oxygen
Answer: B. Remove large debris
Rationale: Bar screens protect equipment by removing
rags, sticks, and other large objects.
,5. Grit removal systems are designed to remove:
A. Organic matter
B. Floatable grease
C. Sand and gravel
D. Dissolved oxygen
Answer: C. Sand and gravel
Rationale: Grit chambers prevent abrasion and
clogging by removing heavy inorganic materials.
6. Primary clarification removes mainly:
A. Dissolved solids
B. Settleable solids
C. Bacteria
D. Nutrients
Answer: B. Settleable solids
Rationale: Primary clarifiers allow heavier solids to
settle by gravity.
7. What is sludge?
A. Clear treated water
B. Floating grease
, C. Settled solids from treatment
D. Disinfectant chemical
Answer: C. Settled solids from treatment
Rationale: Sludge consists of solids removed during
wastewater treatment processes.
8. Secondary treatment primarily removes:
A. Large debris
B. Settleable solids
C. Dissolved organic matter
D. Chlorine
Answer: C. Dissolved organic matter
Rationale: Biological treatment breaks down
dissolved and suspended organic material.
9. Which organisms are mainly responsible for
biological treatment?
A. Viruses
B. Protozoa
C. Bacteria
D. Algae
