During routine sampling, what percentage should be TC negative to comply with TCR?

To comply with the Total Coliform Rule (TCR), the requirement is that at least 95% of the samples taken within a given month must be negative for total coliform bacteria. This standard is in place to ensure the safety of drinking water and protect public health.

Achieving this high percentage indicates that the water supply is effectively free from coliform bacteria, which can signify the presence of harmful pathogens. Meeting this requirement reflects a system's ability to adequately monitor and maintain water quality.

If fewer than 95% of samples are negative, it suggests potential contamination or issues with the water treatment system that need immediate attention and corrective actions.