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Free exam practice for Washington wastewater treatment operators.

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Level I sample questions

Headworks and Screening Practice Questions for Washington Level I

4 free sample questions on headworks and screening for the Washington Level I wastewater treatment operator exam. Try each one, then open the answer to read the explanation.

  1. Question 1

    What is the basic purpose of a **comminutor**?

    1. Measure flow through the channel
    2. Hold rags on stationary bars
    3. Cut solids into smaller pieces
    4. Lift wastewater to a higher point
    Show the answer

    Answer: C. Cut solids into smaller pieces

    A comminutor cuts or shreds solids into smaller pieces while the wastewater continues through the unit.

  2. Question 2

    What is a **bar screen** designed to remove from incoming wastewater?

    1. Dissolved minerals carried with the flow
    2. Fine solids remaining after sedimentation
    3. Large debris such as rags and plastics
    4. Dissolved organic compounds in wastewater
    Show the answer

    Answer: C. Large debris such as rags and plastics

    A bar screen catches large debris such as rags, plastics, sticks, and other objects before they can clog or damage downstream equipment.

  3. Question 3

    What is the main purpose of a bar screen?

    1. To add oxygen to wastewater
    2. To remove large debris from wastewater
    3. To settle biological solids
    4. To disinfect treated effluent
    Show the answer

    Answer: B. To remove large debris from wastewater

    A bar screen removes large debris such as rags, sticks, and trash before it can damage or clog downstream equipment.

  4. Question 4

    What does a comminutor do?

    1. Cuts and shreds coarse solids
    2. Removes dissolved phosphorus
    3. Settles biological solids
    4. Measures chlorine residual
    Show the answer

    Answer: A. Cuts and shreds coarse solids

    A comminutor combines screening and grinding by catching coarse material and cutting or shredding it while it remains in the wastewater flow.

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Operator Master has 4 Level I headworks and screening questions, free, with an explanation after every answer.

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More topics

Other Level I Topics

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  • Math and Calculations10 questions
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  • Secondary Clarification5 questions
  • Biological Treatment4 questions
  • Grit Removal2 questions
  • Laboratory2 questions
  • Primary Treatment2 questions
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