California ICC UST Inspector Practice Exam

A UST containing motor vehicle fuel must provide what percentage of secondary containment?

1. 100%

2. 150%

3. No greater than two feet wide

4. Can be single-walled if equipped with overfill prevention

The correct answer is: 100%

In the context of underground storage tanks (USTs) that contain motor vehicle fuel, secondary containment is a critical measure designed to prevent leaks and spills from contaminating the surrounding environment. The requirement for 100% secondary containment means that the tank must be fully surrounded by a secondary barrier capable of containing any potential leaks or spills. This ensures that even if the primary containment (the storage tank itself) fails, any released fuel will be managed and contained within the secondary system, minimizing the risk of environmental contamination. The emphasis on 100% secondary containment aligns with regulatory measures aimed to enhance safety and environmental protection. These requirements are typically outlined in state regulations and the federal Resource Conservation and Recovery Act (RCRA), both of which dictate that USTs must have systems in place to prevent leaks and to manage any potential releases effectively. Understanding the necessity of 100% containment can motivate compliance with safety standards and encourage the implementation of robust monitoring systems. This helps protect natural resources and public health by ensuring that potential hazards from fuel storage are mitigated effectively.