Question 2018 of 223 · California Water Treatment Operator Exam
What is the effect of backwashing a filter too long at a high rate?
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Correct answer to question 2018
- A: It can wash media out of the filter and disturb the support gravel
Explanation
Excessive backwash rate expands the bed too far and can carry media to waste. Too low a rate leaves the bed dirty and causes mudballs.
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