Texas wastewater Class B Questions and correct
answers (verified download pdf answers) q& a
2026-2027|instant
1. What is the primary purpose of wastewater treatment?
A. Increase wastewater temperature
B. Remove contaminants before discharge or reuse
C. Add chemicals to wastewater
D. Eliminate all microorganisms
Rationale: Wastewater treatment reduces pollutants, protects
public health, and helps meet discharge requirements.
Correct Answer: B. Remove contaminants before discharge or
reuse
2. Which agency regulates wastewater operators and licensing
requirements in Texas?
A. EPA only
B. Texas Commission on Environmental Quality (TCEQ)
C. OSHA
D. USDA
Rationale: TCEQ regulates wastewater treatment facilities and
operator certification in Texas.
,Correct Answer: B. Texas Commission on Environmental
Quality (TCEQ)
3. What is the first stage of most wastewater treatment
processes?
A. Disinfection
B. Secondary treatment
C. Preliminary treatment
D. Sludge digestion
Rationale: Preliminary treatment removes large debris and
protects downstream equipment.
Correct Answer: C. Preliminary treatment
4. Screens at a wastewater plant are designed to remove:
A. Dissolved oxygen
B. Large solids and debris
C. Bacteria
D. Nutrients
Rationale: Screens remove items such as rags, plastics, and
large materials from influent wastewater.
Correct Answer: B. Large solids and debris
5. What is the purpose of a grit chamber?
,A. Remove sand and heavy inorganic particles
B. Add chlorine
C. Increase biological activity
D. Remove dissolved gases
Rationale: Grit chambers protect pumps and equipment by
removing abrasive materials.
Correct Answer: A. Remove sand and heavy inorganic particles
6. Primary treatment mainly removes:
A. Dissolved oxygen
B. Settleable solids and floating materials
C. Viruses only
D. Nutrients only
Rationale: Primary clarifiers remove solids through settling and
skimming.
Correct Answer: B. Settleable solids and floating materials
7. The biological process used in secondary treatment relies
mainly on:
A. Chemicals
B. Microorganisms
C. Heat
D. Pressure
, Rationale: Microorganisms consume organic pollutants during
secondary treatment.
Correct Answer: B. Microorganisms
8. BOD stands for:
A. Biological Oxygen Demand
B. Bacterial Oxygen Density
C. Biological Organic Drainage
D. Basic Oxygen Development
Rationale: BOD measures the oxygen required by
microorganisms to break down organic matter.
Correct Answer: A. Biological Oxygen Demand
9. High BOD levels indicate:
A. Low organic pollution
B. High oxygen demand from pollutants
C. High chlorine levels
D. Pure water quality
Rationale: More organic material requires more oxygen for
decomposition.
Correct Answer: B. High oxygen demand from pollutants
10. Dissolved oxygen (DO) is important because it:
answers (verified download pdf answers) q& a
2026-2027|instant
1. What is the primary purpose of wastewater treatment?
A. Increase wastewater temperature
B. Remove contaminants before discharge or reuse
C. Add chemicals to wastewater
D. Eliminate all microorganisms
Rationale: Wastewater treatment reduces pollutants, protects
public health, and helps meet discharge requirements.
Correct Answer: B. Remove contaminants before discharge or
reuse
2. Which agency regulates wastewater operators and licensing
requirements in Texas?
A. EPA only
B. Texas Commission on Environmental Quality (TCEQ)
C. OSHA
D. USDA
Rationale: TCEQ regulates wastewater treatment facilities and
operator certification in Texas.
,Correct Answer: B. Texas Commission on Environmental
Quality (TCEQ)
3. What is the first stage of most wastewater treatment
processes?
A. Disinfection
B. Secondary treatment
C. Preliminary treatment
D. Sludge digestion
Rationale: Preliminary treatment removes large debris and
protects downstream equipment.
Correct Answer: C. Preliminary treatment
4. Screens at a wastewater plant are designed to remove:
A. Dissolved oxygen
B. Large solids and debris
C. Bacteria
D. Nutrients
Rationale: Screens remove items such as rags, plastics, and
large materials from influent wastewater.
Correct Answer: B. Large solids and debris
5. What is the purpose of a grit chamber?
,A. Remove sand and heavy inorganic particles
B. Add chlorine
C. Increase biological activity
D. Remove dissolved gases
Rationale: Grit chambers protect pumps and equipment by
removing abrasive materials.
Correct Answer: A. Remove sand and heavy inorganic particles
6. Primary treatment mainly removes:
A. Dissolved oxygen
B. Settleable solids and floating materials
C. Viruses only
D. Nutrients only
Rationale: Primary clarifiers remove solids through settling and
skimming.
Correct Answer: B. Settleable solids and floating materials
7. The biological process used in secondary treatment relies
mainly on:
A. Chemicals
B. Microorganisms
C. Heat
D. Pressure
, Rationale: Microorganisms consume organic pollutants during
secondary treatment.
Correct Answer: B. Microorganisms
8. BOD stands for:
A. Biological Oxygen Demand
B. Bacterial Oxygen Density
C. Biological Organic Drainage
D. Basic Oxygen Development
Rationale: BOD measures the oxygen required by
microorganisms to break down organic matter.
Correct Answer: A. Biological Oxygen Demand
9. High BOD levels indicate:
A. Low organic pollution
B. High oxygen demand from pollutants
C. High chlorine levels
D. Pure water quality
Rationale: More organic material requires more oxygen for
decomposition.
Correct Answer: B. High oxygen demand from pollutants
10. Dissolved oxygen (DO) is important because it:
