1|Page
CA Grade 2 Wastewater Treatment
Operator Practice Exam 1|Certified
Q&A 2026
Which of the following is true about the extended aeration process? - correct-
answer-it does not produce as much waste sludge as other processes
What is the correct formula for solids in raw wastewater? - correct-answer-Non
settleable solids + settleable solids = total suspended solids
What is freeboard in a waste stabilization pond? - correct-answer-the vertical
distance from normal water surface to the top of the levee
What is one of the requirements for a BOD test? - correct-answer-The BOD bottle
should be completely filled to the top
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What should be scheduled every 3 months for a flamer arrester in an anaerobic
digester? - correct-answer-maintenance
What is common practice in an activated sludge process? - correct-answer-
recirculate activated sludge
Prior to entering a permit-required confined space, what should you verify? -
correct-answer-a standby person should be located outside the entrance to the
confined space, while another person should be within sight or call of the standby
person
What is a common way to determine the organic strength of wastes in the
influent? - correct-answer-test for the biochemical oxygen demand
, 3|Page
What should you do if you are mildly exposed to chlorine gas? - correct-answer-
immediately evacuate the contaminated area, remian calm, keep warm. breath
lightly, avoid coughing
What are the main sources of domestic sewage in the collection system? -
correct-answer-household and commercial establishments
Why is it important to maintain a horizontal weir in a clarifier? - correct-answer-
to prevent short circuiting
What are mostly removed in the grit channel? - correct-answer-sand, eggshells,
cinders, and heavier particulate matter
CA Grade 2 Wastewater Treatment
Operator Practice Exam 1|Certified
Q&A 2026
Which of the following is true about the extended aeration process? - correct-
answer-it does not produce as much waste sludge as other processes
What is the correct formula for solids in raw wastewater? - correct-answer-Non
settleable solids + settleable solids = total suspended solids
What is freeboard in a waste stabilization pond? - correct-answer-the vertical
distance from normal water surface to the top of the levee
What is one of the requirements for a BOD test? - correct-answer-The BOD bottle
should be completely filled to the top
,2|Page
What should be scheduled every 3 months for a flamer arrester in an anaerobic
digester? - correct-answer-maintenance
What is common practice in an activated sludge process? - correct-answer-
recirculate activated sludge
Prior to entering a permit-required confined space, what should you verify? -
correct-answer-a standby person should be located outside the entrance to the
confined space, while another person should be within sight or call of the standby
person
What is a common way to determine the organic strength of wastes in the
influent? - correct-answer-test for the biochemical oxygen demand
, 3|Page
What should you do if you are mildly exposed to chlorine gas? - correct-answer-
immediately evacuate the contaminated area, remian calm, keep warm. breath
lightly, avoid coughing
What are the main sources of domestic sewage in the collection system? -
correct-answer-household and commercial establishments
Why is it important to maintain a horizontal weir in a clarifier? - correct-answer-
to prevent short circuiting
What are mostly removed in the grit channel? - correct-answer-sand, eggshells,
cinders, and heavier particulate matter
