One of the biggest concerns with above-ground storage tanks is groundwater protection. This is because the vast majority of these tanks contain petroleum products.

When corrosion or some other force compromises the exterior structural integrity of the tank, those petroleum products can contaminate freshwater groundwater supplies, which are already dwindling to problematic levels in some areas of the world. What has been done to prevent corrosion in these tanks in the past will be what guides us toward corrosion prevention techniques of the future.

The concrete and aluminum materials used in constructing the new Guam Navy Hospital's storage tanks are a perfect example of where the industry is heading. It is a great lesson in where today's techniques are leading us as the industry adapts to new and emerging anti-corrosion technologies.

Lessons learned from old techniques

The most important lesson the old techniques have taught us is that they are temporary. Corrosion might be caught, halted and fixed in above-ground storage tanks, but it will eventually come back.

Replacing the tank isn't enough, because it will be susceptible to the same problems as the old tank. Today's companies want tanks that will last for as long as the company lasts. They don't want to have to keep buying new tanks every time one seems like corrosion has damaged it too much to fix it again.

Good corrosion protection means keeping the tank corrosion-free under the harshest of conditions for decades to come. It is what our customers expect, and what we must give them if we are to remain relevant as an industry in the future. We must keep up with the times.

Where the future is leading us

We can expect more frequent corrosion testing of above-ground tanks going forward. This will head off potential problems with the tanks before they become so big a tank replacement is necessary. New materials will be developed and used for building these tanks; focus will be placed on mold- and mildew-resistant materials, as well as rust-resistant materials.

Higher-grade protective coatings for the interiors of the tanks will be developed and used to keep corrosion at bay. Soil testing will be done before installing a tank to make sure the soil does not contain highly corrosive materials; if it does, tanks will be built on platforms that will allow them to avoid contact with the ground.

These techniques are already starting to be used in government projects, particularly the testing of soil before installing a tank. As the government sector sees greater success with these methods, the private sector will be quick to adopt these techniques, as well.

Further advancements through new materials

Higher-quality concrete is one advanced technique being used at the new Guam Navy Hospital. This "concrete of the future" is completely resistant to intrusion of water or chloride into the tank. This mitigates corrosion and keeps the tanks in good condition indefinitely.

Using it at the Guam Navy Hospital was a good test of its capacity to resist corrosion, as the salty air on Guam is a perfect environment for corrosion to occur. So far, the concrete is holding up perfectly.

This new concrete contains a low water-to-cement ratio, and has silica fume, fly ash and galvanized steel components. It also uses aggregates in the concrete that make it more alkaline, which makes it more resistant to corrosion.

Further, doors on above-ground storage tanks will have aluminum doors and windows, rather than the more commonly used coated carbon steel of today. This design was also used at the Guam Navy Hospital, and it shows exactly what new corrosion prevention technology can do. Aluminum has a greater resistance to corrosion than traditional door and window materials on above-ground tanks.

Finally, some metals cause corrosion when they touch each other. Future storage tanks will be designed to separate these metals using protective coatings that are applied after surface prep, and will prevent galvanic corrosion on the tanks.

These are just a few of the things we can look forward to in the prevention of corrosion in above-ground storage tanks as the technology for doing so increases and improves.