What does the term "release" refer to in the context of USTs?

In the context of underground storage tanks (USTs), the term "release" specifically refers to the spilling or leaking of petroleum or hazardous substances from the tank. This definition is crucial because releases can lead to significant environmental contamination and pose health risks to nearby communities. Understanding this term is essential for those responsible for monitoring and managing USTs, as it emphasizes the importance of maintaining the integrity of the storage tanks to prevent environmental harm.

While other options present actions related to petroleum products and hazardous substances, they do not encapsulate the urgent environmental concern associated with accidental discharges, which is the focus of the term "release" in UST regulation and oversight.