Underside Corrosion of above Ground Storage Tanks (ASTs)

Underside corrosion of a failed above ground storage tank (AST) was investigated by the physiochemical analysis of water sample that was ingress between the tank bottom plate and the concrete foundation. The results of the water sample analysis showed pH (5.8), temperature (30°C), Conductivity (4800 μs/cm), dissolved oxygen (3.5 mg/l), chloride (674 mg/l), carbonate (16.90mg/l) and nitrate (23.10 mg/l). The levels of the parameters studied were generally high and above statutory safe limits. The results showed that the physico-chemical characteristics of the water sample have diagnostic and predictive values to implicate and promote underside corrosion of the studied above ground storage tank.