All routine coliform test results must be reported to the state by the ______ of the following month:

• A. first
• B. fifth
• C. tenth
• D. fifteenth

Answer: (C)

The key idea is the timing of official reporting for routine drinking-water test results. Routine coliform results must be sent to the state by the tenth day of the month following sampling. This deadline lines up with how agencies compile and review monthly surveillance data, giving labs a reasonable window to complete analyses and ensure accuracy before submission. Reporting earlier isn’t practical because some tests may not be finalized yet, while reporting later delays public health monitoring and any needed responses. So the tenth day of the following month is the intended deadline.