What containment measure can be implemented to prevent fuel leakage from USTs?

Secondary containment systems are crucial in preventing fuel leakage from underground storage tanks (USTs) because they provide an additional layer of protection surrounding the primary tank. These systems are designed to contain any leaking fuel, thereby preventing contamination of the surrounding soil and groundwater.

Secondary containment can be implemented through a variety of methods, such as installing a double-walled tank where the outer wall serves as a barrier to catch any leaks from the inner tank. Alternatively, other systems may involve a containment trench or a concrete vault. The effectiveness of these systems is tied to their ability to detect leaks early and contain potential spills.

In contrast, a single-walled design does not offer this level of protection, as it relies solely on the integrity of one tank wall. Frequent manual inspections, while necessary, do not prevent leaks but only help in detecting them after they occur. Decreasing monitoring intervals may improve the detection of leaks but does not actively prevent them from occurring. Therefore, secondary containment systems are the most effective measure for preventing fuel leakage in USTs.