A ground double-wall diesel fuel storage tank is a specialized containment system designed for the safe, long-term storage of diesel fuel above ground. As the name implies, it features an inner tank (primary wall) that holds the fuel and an outer tank (secondary wall) that surrounds it, creating a protective gap or annulus between the two layers. This dual-wall construction is critical for preventing leaks, spills, and environmental contamination, making it compliant with strict safety and environmental regulations in many regions.

In the event of a leak in the primary tank, the secondary wall contains the spilled fuel within the annulus, preventing it from escaping into the soil or groundwater. Many systems include monitoring mechanisms (e.g., sensors, pressure gauges, or manual inspection ports) in the gap to detect leaks early, ensuring timely maintenance and reducing environmental risk.

These tanks are widely used in industrial facilities, transportation depots, power plants, and commercial sites where large volumes of diesel fuel are stored for backup generators, vehicle fleets, or machinery. Their above-ground placement allows for easy inspection, maintenance, and compliance with fire safety standards, as they can be equipped with fire-resistant coatings, spill containment berms, or heat-insulating layers. Compared to single-wall tanks, double-wall designs offer enhanced durability and redundancy, making them a preferred choice in areas with strict environmental protection laws. Proper installation, regular testing (e.g., hydrostatic or ultrasonic testing), and adherence to codes (such as API 650 or NFPA 30) are essential to ensure their reliability and safety throughout their operational lifespan.