What is a key characteristic of a spill catchment basin?

A spill catchment basin is designed to capture any spills or overflows that may occur during the transfer of liquid to or from a storage tank. The essential characteristic of a spill catchment basin is that it is liquid-tight and surrounds the fill port, ensuring that any accidental spillage is contained within the basin instead of leaking into the environment. This containment feature is crucial for preventing environmental contamination and maintaining compliance with regulatory requirements.

The other characteristics mentioned, such as being always above ground or larger than the storage tank, are not accurate or may not apply universally to all spill catchment basins. Similarly, while preventing tank corrosion is an important consideration in tank design and maintenance, it is not a defining feature of a spill catchment basin itself. Instead, the focus of a spill catchment basin is on containment, making the characteristic of being liquid-tight and surrounding the fill port pivotal to its function.