Wastewater Grade 1 Exam Questions
and Answers | Latest Version |
2025/2026 | Correct & Verified
What is the primary purpose of a wastewater treatment plant?
✔✔To remove pollutants and produce safe effluent before discharge.
Why is screening used in wastewater treatment?
✔✔To remove large debris and prevent damage to equipment.
What is the function of grit removal in a treatment plant?
✔✔To settle out sand, gravel, and heavy inorganic particles.
Why is primary sedimentation performed?
✔✔To remove settleable solids from wastewater.
What is biological treatment in wastewater?
✔✔Using microorganisms to break down organic matter.
1
,Why is dissolved oxygen important in aerobic treatment processes?
✔✔It supports the growth of aerobic bacteria that decompose organic waste.
What is the purpose of a clarifier in wastewater treatment?
✔✔To separate solids from treated water by settling.
Why is sludge thickening necessary?
✔✔To reduce the water content and volume of sludge for handling.
What is the function of an aeration tank?
✔✔To mix wastewater with air and promote biological decomposition.
Why is chemical addition sometimes used in treatment?
✔✔To enhance settling, remove phosphorus, or disinfect effluent.
What is the main purpose of disinfection in wastewater treatment?
✔✔To kill pathogens and reduce the risk of disease.
2
, Why must influent flow rates be measured?
✔✔To control treatment processes and ensure proper hydraulic loading.
What is the function of a bar screen?
✔✔To remove large floating objects and debris from incoming wastewater.
Why is pH monitoring important in wastewater treatment?
✔✔To maintain optimal conditions for biological processes.
What is the purpose of a sludge digester?
✔✔To stabilize sludge and reduce pathogens and odor.
Why is effluent testing performed?
✔✔To ensure treated water meets regulatory discharge standards.
What is the function of a lift station in a wastewater system?
✔✔To pump wastewater from low-lying areas to higher elevations.
3
and Answers | Latest Version |
2025/2026 | Correct & Verified
What is the primary purpose of a wastewater treatment plant?
✔✔To remove pollutants and produce safe effluent before discharge.
Why is screening used in wastewater treatment?
✔✔To remove large debris and prevent damage to equipment.
What is the function of grit removal in a treatment plant?
✔✔To settle out sand, gravel, and heavy inorganic particles.
Why is primary sedimentation performed?
✔✔To remove settleable solids from wastewater.
What is biological treatment in wastewater?
✔✔Using microorganisms to break down organic matter.
1
,Why is dissolved oxygen important in aerobic treatment processes?
✔✔It supports the growth of aerobic bacteria that decompose organic waste.
What is the purpose of a clarifier in wastewater treatment?
✔✔To separate solids from treated water by settling.
Why is sludge thickening necessary?
✔✔To reduce the water content and volume of sludge for handling.
What is the function of an aeration tank?
✔✔To mix wastewater with air and promote biological decomposition.
Why is chemical addition sometimes used in treatment?
✔✔To enhance settling, remove phosphorus, or disinfect effluent.
What is the main purpose of disinfection in wastewater treatment?
✔✔To kill pathogens and reduce the risk of disease.
2
, Why must influent flow rates be measured?
✔✔To control treatment processes and ensure proper hydraulic loading.
What is the function of a bar screen?
✔✔To remove large floating objects and debris from incoming wastewater.
Why is pH monitoring important in wastewater treatment?
✔✔To maintain optimal conditions for biological processes.
What is the purpose of a sludge digester?
✔✔To stabilize sludge and reduce pathogens and odor.
Why is effluent testing performed?
✔✔To ensure treated water meets regulatory discharge standards.
What is the function of a lift station in a wastewater system?
✔✔To pump wastewater from low-lying areas to higher elevations.
3
