To limit the probability of the escape and spread of flammable liquids and combustible liquids from the tank in the event the integrity of the primary containment is compromised, which could lead to contamination of the soil, which could lead to contamination of the water table, which could lead to accidental ignition of liquid or vapour from a nearby ignition source, which could lead to damage to the building or facility.
To direct Code users to Subsection 4.3.1.