What is the minimum sampling frequency for volatile organic compounds (VOCs)?

The minimum sampling frequency for volatile organic compounds (VOCs) being once per year is based on regulatory requirements and the need to adequately monitor for these contaminants in water systems. VOCs can be harmful to human health and the environment, and annual sampling ensures that any potential issues can be identified and addressed promptly. This frequency balances the need for monitoring with the resources available for testing while allowing enough time to observe trends or changes in contamination levels.

Sampling more frequently than once per year could result in unnecessary expenditures if contamination levels remain stable, whereas sampling less frequently would not provide sufficient data to ensure safety and compliance with health standards. Thus, annual monitoring represents a practical approach to ensuring the safety of water supplies from VOC contamination.