What is the function of a transition sump in UST systems?

The function of a transition sump in UST systems is primarily to collect spills and overfills that may occur during fuel delivery. This is crucial for maintaining environmental safety and compliance with regulations. During the process of delivering fuel to an underground storage tank, there is always a risk of overflow or spillage, especially if the delivery process is not perfectly managed.

The transition sump serves as a catchment area to capture any excess fuel that may escape from the loading process, thus preventing it from leaking into the surrounding environment. It acts as a safeguard to help mitigate potential contamination of soil and water from fuel spills, which is a primary concern in the management of underground storage systems.

While other options may relate to functionalities within fuel systems, such as monitoring fuel quality or providing extra storage space, they do not specifically pertain to the role of a transition sump. The focus of a transition sump is clearly defined in its role in spill containment during fuel delivery operations.