What samples must be collected if groundwater is present during assessment?

When groundwater is present during an assessment, it is essential to collect delineation and site assessment samples. This is because groundwater can act as a pathway for contaminants, and understanding the extent of contamination and the impact on groundwater quality is critical for a comprehensive site assessment. Delineation samples help define the boundaries of contamination, allowing for effective remediation planning and risk assessment.

Moreover, site assessment samples are necessary for evaluating the environmental conditions and potential risks associated with the heating oil tank. By collecting these samples, supervisors can gather vital information that enhances the understanding of the contamination's scope and aids in compliance with environmental regulations.

The importance of collecting these samples lies in their role in protecting both public health and the environment, thereby ensuring that any risks posed by the presence of groundwater are thoroughly investigated and addressed.