Florida Drinking Water Operator "B" Practice Test

What do tiny alum floc formations in the flocculation basin indicate?

1. The alum dose is too high

2. The dose is too low

3. The water temperature is too high

4. The basin is not functioning

The correct answer is: The dose is too low

Tiny alum floc formations in the flocculation basin typically indicate that the alum dosage is too low. This is because the primary role of alum, a coagulant, is to aid in the aggregation of finer particulates into larger flocs that can be more easily removed from the water during subsequent sedimentation and filtration processes. When the dosage is insufficient, the expectation is that larger, denser flocs will not form effectively, leading to the presence of smaller, less cohesive floc particles. The presence of tiny floc formations suggests that while some coagulation is occurring, it is not adequate enough to achieve optimal floc size and settling characteristics. Operators need to monitor alum dosage carefully to ensure that it meets the requirements of the specific water chemistry and treatment objectives. Adjustments may need to be made to enhance coagulation, which will ultimately improve the efficiency of downstream processes.