Keep It Clean - Fuel
Storage Tank Maintenance
Most owners and operators of fuel storage tanks do not understand that
maintenance is required to safely and successfully operate fuel storage tanks.
We constantly hear that customers have tanks that have never been cleaned and
worse yet, that they believe that they never need to check to see if they have
This is made even worse by the information that some fuel suppliers tell their
customers; for example that it OK to have some water at the bottom of the tank.
Well here is some real world information for everyone on this subject.
Fuel Storage Tanks all require regular maintenance. They are designed with the
pickup tube 3" to 6" from the tank bottom so that small amounts of water,
sediment and other contaminants have a space they can settle out so that they
will not be drawn into the vehicle or equipment tanks as fuel is pumped out.
This water and sediment material will accumulate over time and will cause
problems if not removed periodically.
Some will tell you that 1/2" or 1" or even 2" of water is alright, and they are
flat out wrong. Every time fuel is transferred into that tank it stirs up all
that material and it may take as long as a day for it to settle out again. In
the meantime every tank you dispense fuel into gets some of this material.
If you have a steel tank that water is corroding your tank from the inside out
and putting rust particles into your fuel. We often find above ground tanks only
a few years old that have rusted from the inside to the point of leaking from
water and sludge in the tank.
Many customers have electronic monitoring systems that provide constant readings
showing fuel level, water level, and leak detection. Some of these customers
will see 1/2" or a few gallons of water on these system and ignore it because
they have been told it is not important.
One problem we see time and again is that the sensors on these monitoring
systems fail and they don't tell you when they fail, they just go on showing the
last reading forever. This goes on until they start pumping water into their
equipment at which point someone checks the tank with a stick and water finding
paste only find that they actually have several inches of water.
We have told all of our customers for many years that even though you have spent
several thousand dollars for a state of the art monitoring system, you still
need to have some one check every tank at least once a month with a stick and
water finding paste.
And this rule should be written next to the monitor and maybe next to where you
store the measuring stick: "The Only
Acceptable Amount of Water in Any Fuel Storage Tank is ZERO (0)".
For those of your with in-ground steel tanks, these tanks have Sacrificial
Anodes attached to them. These Anodes take the weak electrical current generated
by the tank and pass it into the ground through them. This prevents the tank
metal from corroding, however the Anode "Sacrifices" itself in this process. The
Anode is used up over a period of time. When the Anode is "used up" the tank
begins to corrode often very quickly. Tank owners should periodically check
these Anodes and Replace them as necessary. In many states this is part of the
required maintenance and testing procedures, however you should know this and
check to be certain it has been properly done.
Caps, Sumps, and Vents should all be checked for integrity and to see that they
are doing their intended job.
Fuel Storage is a vital link in getting clean fresh fuel safely and efficiently
into vehicles and equipment. You have a big investment in the tank, its
installation, and in the fuel in it. It only makes sense to properly maintain
and protect this investment.
Today we have new challenges with Ultra-Low Sulfur Diesel (ULSD),
Gasohol, Conventional Gasoline, and Reformulated Gasoline containing any amount
of Ethanol. These fuel products hold much higher levels of water and are much
more corrosive than fuels we have traditionally dealt with. They require much
higher levels of monitoring and maintenance to have a safe and trouble free
We are happy to offer analysis and suggestions on how to operate and maintain
Please post your comments or questions here.