To permanently close a tank, what is NOT a required action?

When permanently closing a tank, certain procedures must be followed to ensure environmental safety and compliance with regulations. Filling all voids with water is not a required action during the closure process as per current UST regulations. Instead, the focus is on properly emptying and cleaning the tank, disconnecting all associated piping, and removing the tank from the ground if that is necessary.

In fact, tanks are often filled with inert materials or left empty after being cleaned to prevent collapse and to minimize potential residual contamination. Therefore, the key actions involved in the closure process prioritize the removal of hazards and compliance with environmental regulations, rather than filling voids with water. This makes the action of filling all voids with water unnecessary in the context of permanently closing a tank.