If Tank 1, Tank 2, and the final pH all show a reading of 11.00, what might be malfunctioning?

• A. The acidity of the wastewater
• B. The mixing processes in the tanks
• C. The acid pumps
• D. The pH probes

Answer: (C)

When Tank 1 and Tank 2 both show a consistent pH reading of 11.00, along with the final pH also at 11.00, it suggests that there is an issue affecting the expected treatment process. Typically, as wastewater undergoes treatment, one would anticipate pH variations due to the addition of chemicals (such as acids) that are used in processes like neutralization.

If the acid pumps are malfunctioning, they may not be introducing the necessary acids into the tanks to lower the pH to a more neutral level. In a properly functioning system, you would expect to see changes in pH readings throughout the treatment process as the pH is adjusted according to the specific needs of the wastewater being treated. Since all three readings remain constant at an elevated pH of 11.00, it strongly indicates that the acid pumps are not operating effectively to bring the pH down, which is critical for adequate treatment and compliance with discharge regulations.

Thus, the indication of a uniform high pH across all points implies that the acid pumps are the likely point of failure in this scenario, resulting in inadequate pH correction throughout the treatment process.