What term refers to boundaries that prevent the passage of water or oil?

The term that accurately describes boundaries that prevent the passage of water or oil is "water or oil tight boundaries." These boundaries are specifically designed to contain liquids, ensuring that they do not leak or escape from a defined area. This is crucial in various contexts, such as engineering, environmental management, and safety measures, where the control of spills or leaks is essential to maintain safety and prevent environmental contamination.

Water or oil tight boundaries are constructed to withstand the pressure and potential flow of liquids, employing materials and techniques suited for this purpose, thus ensuring effective containment. In contrast, the other options do not specifically denote the ability to contain these substances, making them less suitable for the definition in question.