How does the "double-walled" design of USTs improve safety?

The double-walled design of underground storage tanks (USTs) provides a crucial safety benefit by incorporating an outer wall that serves as a secondary containment barrier for the inner tank. This feature is specifically designed to address the risk of leaks or failures in the inner tank, which can occur due to corrosion, physical damage, or material degradation over time. If a leak occurs in the inner wall, the outer wall captures and contains any spilled substance, preventing it from escaping into the surrounding environment. This significantly mitigates the risk of soil and groundwater contamination, thereby protecting public health and the ecosystem.

By containing any potential leaks within the outer wall, this design enhances the overall reliability and safety of USTs, making it a critical component in compliance with environmental regulations aimed at preventing hazardous substance releases.