What role does a supervisor have during the application of restricted-use pesticides?

The supervisor's role during the application of restricted-use pesticides primarily revolves around ensuring compliance with safety and regulatory standards. The correct answer highlights that the supervisor must be contactable when needed, indicating that while they do not have to be physically present at the application site, they must remain accessible for guidance, oversight, and decision-making as necessary.

This ensures that any immediate questions or issues that arise can be addressed promptly, thereby maintaining safe application practices. It is also critical for a supervisor to be available for checking compliance with environmental protocols and safety measures.

The other options suggest a level of supervision that might not be practical or necessary. For instance, being required to be on-site at all times can be unrealistic and unnecessary for effective management. Additionally, supervision from a distance does not fulfill the responsibility of being readily available for support and oversight. Likewise, placing all responsibility for application decisions on the supervisor could hinder the ability of trained applicators to make judgment calls in the field, which is often essential for safe and effective pesticide use.

Thus, the emphasis on being contactable supports a balanced approach to supervision, promoting safety and compliance without imposing unrealistic expectations.