Which of the following sampling types is considered discretionary?

Discretionary sampling refers to water quality testing that is not mandated by regulations and is instead conducted at the discretion of the water utility or agency performing the sampling. This type of sampling allows for flexibility in testing based on the unique needs, conditions, or concerns of the water system being evaluated.

The chosen answer pertains specifically to chemical testing that is not required for compliance with regulatory standards. This could include testing for substances that are not regularly monitored or that do not have specified limits set by environmental authorities. Such discretionary testing can be beneficial for proactive management and for addressing specific local concerns regarding water quality that may not be covered by routine compliance requirements.

In contrast, the other types of sampling mentioned are typically required by regulations and are essential for maintaining compliance with established environmental standards, which means they do not fall under the discretionary category. Lead and copper sample collection and compliance monitoring samples are specifically mandated to ensure safe levels of contaminants in drinking water. Secondary contaminant sampling, while it can be less stringent than primary sampling, still generally adheres to specific guidelines and requirements, making it non-discretionary.