Question 6025 of 223 · California Water Treatment Operator Exam
A filter with an area of 250 sq ft is backwashed at 20 gpm/sq ft for 8 minutes. What volume of backwash water is used?
Exactly one answer is correct.
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Correct answer to question 6025
- C: 40,000 gallons
Explanation
Flow = 250 x 20 = 5,000 gpm. Volume = 5,000 x 8 = 40,000 gal. Without the time, the answer is just the flow.
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