What is the maximum contamination level (MCL) for turbidity in water treatment?

The maximum contaminant level (MCL) for turbidity is crucial in water treatment as it reflects the clarity and overall quality of water being supplied to consumers. The value set by regulatory agencies, particularly the U.S. Environmental Protection Agency (EPA), is that the turbidity should not exceed 0.3 NTU (Nephelometric Turbidity Units) in any single sample for a water treatment facility that serves more than 1,000 people. Additionally, the MCL allows for a level of 1.0 NTU as a maximum for monthly averages.

Therefore, option C accurately aligns with the established guidelines, stating 0.3 NTU for monthly measurements and up to 1.0 NTU for instantaneous readings. These standards are designed to ensure that water treatment processes effectively remove particles and pathogens, thereby safeguarding public health. Proper understanding and application of these MCLs help maintain water quality and comply with regulatory requirements, which is vital for the safety of drinking water.