If there is no visual evidence of a release upon UST removal, what is required of the operator?

When an underground storage tank (UST) is removed and no visual evidence of a release is detected, it is crucial for the operator to take soil samples and analyze them. This step is necessary to ensure that there are no contaminants present in the soil that could indicate a previous leak or release from the UST. Analyzing soil samples provides a definitive assessment of the environmental condition of the site following the removal of the tank.

Taking soil samples serves as a proactive measure to comply with environmental regulations and protect public health and safety. It helps in confirming that the area is free from harmful substances that could pose risks to the environment or nearby communities. This analysis is also essential for legal compliance and environmental due diligence, as it might be required by local, state, or federal regulations.

The other choices do not adequately address the requirement to assess potential contamination from the UST. While notifying the public, leaving the site as is, or installing a monitoring system might be relevant in different scenarios, they do not fulfill the necessary step of soil sampling and analysis. Thus, taking soil samples represents the most responsible and required action for the operator in the context of UST removal.