1Single Choice
A Class 4 operator observes that the mixed liquor in an aeration basin has a dark, nearly black appearance and a sulfurous odor. Which condition should the operator investigate first?
Reveal the answer to continue
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A Class 4 operator observes that the mixed liquor in an aeration basin has a dark, nearly black appearance and a sulfurous odor. Which condition should the operator investigate first?
Reveal the answer to continue