Water ingress into tank chambers and dispenser sumps is a problem faced by petrol station operators and owners across the world. It's often thought of as an unavoidable normality. However, dealing with water once it has flooded the sump (and possibly the tank itself) can be costly. What's more, if water can get into the sump, leaked fuel can be emitted from the sump into the environment.
The good news is that we have a solution. Using patented UPP Electrofusion Entry Seals for pipework and UPP Tank Sumps with integrated water-tight lids, all possible leak paths are removed. This ensures water is excluded from the tank sump and any leaked fuel remains inside.
Where it happens
There are three main locations where water ingress can be a problem:
- The Sump Lid
Non-water-tight sump lids are a prime location for water ingress, usually as a result of high ground-water when water table levels have risen above the height of the sump wall. Sump lids are damaged or missing, rain water can leak in through the grade level access cover.
- Pipework and Conduit Entry Seals
On a standard pressure system tank sump there can be between 3 and 10 pipe and conduit entry seals allowing pressure, vent, fill, vapour recovery and electric lines to penetrate into the tank sump. Each one of these seals is a potential water ingress/ fuel egress point.
- Tank / Sump Joint
It is common for water table levels to be sitting around the tank to sump interface, usually 1-3 metres below ground. There are different methods of creating this joint, depending upon the type of tank and the type of sump being used. The two most common methods are bonded joints and bolted joints.
[caption id="attachment_856" align="alignnone" width="694" caption="Examples of tank sumps flooded with water."]
The hidden costs
Once a sump is installed and has started taking on water, the only solutions are short-term and reactive and must be repeated many times. For example, water has to be regularly emptied from the flooded tank sumps and, because it is 'contaminated', must be disposed of in a controlled manner. In addition, flood water can cause increased corrosion to tank top furniture items, and water can enter the tank and contaminate the fuel with microorganisms.The solutionUPP Electrofusion Entry Seals
electrofuse to the wall of the tank sump, removing the need for mechanical bolts or threaded pieces or rubber parts. Once fused the seals become one with the sump wall and cannot become loose or corrode over time.UPP Tank Sumps
are designed using specialist computer software (FEA) to prove they can cope with the tough conditions. They are designed to withstand a 6ft head of water pressure with a safety factor of between 5 and 15. Combined with a Virgin Linear Low Density PE construction material and a nominal wall thickness of 8mm they also have great resistance to hydrocarbons and earth movement.