California ICC UST Inspector Practice Exam 2026 – Your All-In-One Guide to Exam Success!

The requirement for secondary containment for hazardous substance and petroleum tanks was first established significantly earlier than many might realize. January 1, 1984 marks a pivotal change in regulations aimed at enhancing environmental safety and protecting groundwater from contamination by underground storage tanks (USTs). This date is noteworthy because it reflects the early legislative actions in the United States, which laid the groundwork for subsequent policies.

The purpose of requiring secondary containment was to ensure that any leaks from a primary tank would be contained and not lead to environmental spills or contamination. This not only helps in safeguarding water resources but also addresses public health concerns by minimizing the potential exposure to hazardous substances.

Later dates mentioned in the other options, such as July 1, 1991, and beyond, are specifically associated with subsequent regulations and updates to standards that expanded or enforced these secondary containment requirements. Therefore, while these dates represent important milestones in the evolution of UST regulations, the correct foundational requirement for secondary containment can be traced back to January 1, 1984.