California ICC UST Inspector Practice Exam

Which statement is NOT true about UST systems installed between July 1, 2003 and July 1, 2004?

1. Product tight means impervious to liquid and vapor of the substance

2. Product tight needs to prevent seepage of contained substances

3. Secondary containment must prevent water intrusion

4. Secondary containment must be product tight to prevent structural weakening

The correct answer is: Product tight means impervious to liquid and vapor of the substance

The statement that product tight means impervious to liquid and vapor of the substance is not true regarding UST systems installed between July 1, 2003, and July 1, 2004. In the context of underground storage tanks (USTs), the term "product tight" refers specifically to the ability of the primary containment (the tank itself) to prevent leaks of the stored substance. However, it does not necessarily imply that the containment system is completely impervious to all liquids and vapors under all conditions. In contrast, the other statements accurately reflect the requirements for those UST systems during that installation period. It's essential for secondary containment systems to prevent water intrusion, as excess water can undermine the integrity of the system. Additionally, secondary containment must indeed be product tight to ensure that external substances do not compromise the structural integrity of the storage system and that they effectively contain any leaks from the primary system. Thus, understanding these nuances in terminology and standards is crucial for compliance and safe operation of UST systems.