Question 1014 of 229 · California Water Distribution Operator Exam
Before a newly disinfected main is placed in service, what must the bacteriological samples show?
Exactly one answer is correct.
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Correct answer to question 1014
- A: No coliform bacteria
Explanation
Samples taken after the main is flushed must be absent for total coliform before it is released. Sampling is repeated if any result is positive.
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