Treatment Plant Operator Exam Study Guide Answers

By allowing a settleometer sample to set for several hours after the 30-minute settling test, what can be determined?The answer to the question is A, denitrification in the system. If you allow a sample to sit for several hours after the 30-minute settling analysis, the sample will eventually rise or flip over and float to the top of the settleometer. This is an indication of denitrification. It is a common occurrence and expected. The amount of time it takes allows the operator to have an idea of possible problems in the clarifier. If the sludge rises too fast (90 minutes or