Question 1013 of 229 · California Water Distribution Operator Exam
A sudden drop of chlorine residual at a dead-end hydrant most likely points to what?
Exactly one answer is correct.
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Correct answer to question 1013
- C: Long water age with chlorine used up by demand or reactions in the pipe
Explanation
Slow-moving water has time to react with biofilm, pipe wall and organics, so residual fades. The usual response is flushing or a looped main.
More questions: Disinfection
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