Texas Wastewater Class A Questions and correct
answers (verified download pdf answers) q& a
2026-2027|instant
1. What is the primary purpose of wastewater treatment?
A. To increase wastewater temperature
B. To remove pollutants before discharge or reuse
C. To add chemicals to wastewater
D. To increase organic loading
Correct Answer: B. To remove pollutants before discharge or
reuse
Rationale: Wastewater treatment protects public health and
the environment by removing contaminants such as solids,
pathogens, and nutrients.
2. Which agency regulates wastewater discharge permits in
Texas?
A. EPA only
B. TCEQ
C. OSHA
D. FEMA
Correct Answer: B. TCEQ
,Rationale: The Texas Commission on Environmental Quality
(TCEQ) administers wastewater permits and regulations in
Texas.
3. What is the first major treatment step in a wastewater
plant?
A. Disinfection
B. Secondary treatment
C. Preliminary treatment
D. Sludge digestion
Correct Answer: C. Preliminary treatment
Rationale: Preliminary treatment removes large debris, rags,
grit, and materials that could damage equipment.
4. Screening in wastewater treatment removes:
A. Dissolved oxygen
B. Large floating solids
C. Bacteria
D. Nutrients
Correct Answer: B. Large floating solids
Rationale: Screens remove items such as plastics, rags, and
sticks from incoming wastewater.
,5. Grit removal is designed to remove:
A. Sand and heavy inorganic particles
B. Dissolved chemicals
C. Viruses
D. Organic bacteria
Correct Answer: A. Sand and heavy inorganic particles
Rationale: Grit consists of dense inorganic materials that can
cause abrasion and equipment damage.
6. The main purpose of primary clarification is to remove:
A. Dissolved oxygen
B. Settleable solids
C. Chlorine
D. Nutrients
Correct Answer: B. Settleable solids
Rationale: Primary clarifiers allow suspended solids to settle
and floating materials to be removed.
7. BOD stands for:
A. Biological Oxygen Demand
B. Bacterial Oxygen Density
C. Biological Organic Drain
D. Basic Oxygen Demand
, Correct Answer: A. Biological Oxygen Demand
Rationale: BOD measures the amount of oxygen
microorganisms require to break down organic matter.
8. High BOD levels in wastewater indicate:
A. Low organic pollution
B. High organic pollution
C. No biological activity
D. Excess chlorine
Correct Answer: B. High organic pollution
Rationale: More organic material requires more oxygen for
decomposition, increasing BOD.
9. Which process uses microorganisms to remove organic
pollutants?
A. Screening
B. Biological treatment
C. Grit removal
D. Chlorination
Correct Answer: B. Biological treatment
Rationale: Microorganisms consume organic waste during
biological treatment.
answers (verified download pdf answers) q& a
2026-2027|instant
1. What is the primary purpose of wastewater treatment?
A. To increase wastewater temperature
B. To remove pollutants before discharge or reuse
C. To add chemicals to wastewater
D. To increase organic loading
Correct Answer: B. To remove pollutants before discharge or
reuse
Rationale: Wastewater treatment protects public health and
the environment by removing contaminants such as solids,
pathogens, and nutrients.
2. Which agency regulates wastewater discharge permits in
Texas?
A. EPA only
B. TCEQ
C. OSHA
D. FEMA
Correct Answer: B. TCEQ
,Rationale: The Texas Commission on Environmental Quality
(TCEQ) administers wastewater permits and regulations in
Texas.
3. What is the first major treatment step in a wastewater
plant?
A. Disinfection
B. Secondary treatment
C. Preliminary treatment
D. Sludge digestion
Correct Answer: C. Preliminary treatment
Rationale: Preliminary treatment removes large debris, rags,
grit, and materials that could damage equipment.
4. Screening in wastewater treatment removes:
A. Dissolved oxygen
B. Large floating solids
C. Bacteria
D. Nutrients
Correct Answer: B. Large floating solids
Rationale: Screens remove items such as plastics, rags, and
sticks from incoming wastewater.
,5. Grit removal is designed to remove:
A. Sand and heavy inorganic particles
B. Dissolved chemicals
C. Viruses
D. Organic bacteria
Correct Answer: A. Sand and heavy inorganic particles
Rationale: Grit consists of dense inorganic materials that can
cause abrasion and equipment damage.
6. The main purpose of primary clarification is to remove:
A. Dissolved oxygen
B. Settleable solids
C. Chlorine
D. Nutrients
Correct Answer: B. Settleable solids
Rationale: Primary clarifiers allow suspended solids to settle
and floating materials to be removed.
7. BOD stands for:
A. Biological Oxygen Demand
B. Bacterial Oxygen Density
C. Biological Organic Drain
D. Basic Oxygen Demand
, Correct Answer: A. Biological Oxygen Demand
Rationale: BOD measures the amount of oxygen
microorganisms require to break down organic matter.
8. High BOD levels in wastewater indicate:
A. Low organic pollution
B. High organic pollution
C. No biological activity
D. Excess chlorine
Correct Answer: B. High organic pollution
Rationale: More organic material requires more oxygen for
decomposition, increasing BOD.
9. Which process uses microorganisms to remove organic
pollutants?
A. Screening
B. Biological treatment
C. Grit removal
D. Chlorination
Correct Answer: B. Biological treatment
Rationale: Microorganisms consume organic waste during
biological treatment.
