Water in Oil Storage Tanks - an owner's guide to measuring and removing oil tank water contamination InspectAPedia® -
This article tells you what to do about finding and removing water from oil storage tanks regardless
of whether the oil tank is indoors, outdoors above ground, or buried.
Why is water in an oil tank a problem?
How water gets into an oil storage tank
Assessing the level of water in an oil tank: water finder paste, instruments, visual inspection
How to remove water from an oil storage tank: water absorbing pads, pumping out water from an oil tank
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Here we explain how to test for or visually check for water in a buried or above-ground oil storage tank, and how to get water out of an oil tank. Extensive free un-biased oil storage tank inspection and testing advice for property buyers and owners is provided at this website.
This document lets you know what to ask about oil storage tanks, what oil tank leak tests to order,
how to interpret oil tank testing results,
what to do if there is a buried fuel or petroleum storage tank at a property, what to do if there is or was a leaky oil storage tank or
petroleum storage tank, and how to
reduce the chances of an oil leak or oil spill in the future. Also see TEST OIL TANKS FOR WATER for more about testing oil tanks for water leaks and damage.
We include detailed information about underground (buried) oil storage tanks (USTs),
aboveground oil storage tanks (ASTs), above ground fuel storage tanks, reporting and cleaning up oil tank leaks, and choosing among oil tank leak testing methods.
Home buyers should be sure to review
OIL TANK TESTING - Leaky Heating Oil Tanks - How Oil Tanks are Tested for Evidence Leaks, of Current or Previous Oil Spills
and Tank Legal Issues - Home Buyers and Home Owners Guide to Leaky Heating Oil Tanks - What to Do About & When to Report Oil Tank Leaks. Leaky Heating Oil Tanks.
Home owners who have old oil tanks above ground or any age oil tank below ground should also be sure to review OIL TANK ABANDONING PROCEDURE - Abandoning Commercial vs. Residential Underground Oil Storage Tanks (UST) - Procedures & Regulations
A separate website addresses Septic Tanks.
Testing for and Removing Water Contamination from Oil Storage Tanks
Testing an oil tank for for water contamination in an oil tank (above ground oil tanks whether inside or outdoors, or buried oil tanks)
is simple and can be done by any service
person or even a homeowner.
Oil Tank testing methods for oil leaks vary in risk to the tank, cost, invasiveness,
length of time to complete, and more.
Since water in a heating oil tank can lead to loss of heat and related building damage
we want to know if in-tank water is a problem at a given property. There are several
steps and test methods for finding water in an oil tank and for determining how much
of a problem it is.
Water can enter a heating oil storage tank by several means
Water enters a buried or above ground tank by condensation: as temperatures vary moisture-containing air may be drawn into and then out
of an oil tank.
Air leaves the tank as oil is consumed; air enters and leaves the oil tank through the oil tank vent. Moist air entering the tank
from outside can bring water which, on entering the cooler tank interior, condenses out of vapor form into water droplets which can, over time
accumulate.
Water enters a tank filler pipe: from roof spillage onto the tank or filler top (particularly and obviously if the filler cap is left off),
or from ground or surface runoff entering the oil storage tank (particularly and obviously if the filler cap is near, at, or below ground surface level).
Leaving off an outside oil tank filler cap for a few days is not itself a likely source of a problem unless the filler
was exposed to heavy rain, roof runoff spillage onto the open filler pipe, or surface runoff entering the tank
(such as for a filler pipe flush with the ground).
Water leaks into a buried oil tank from an actual tank perforation that admits ground water, or from a bad plumbing fitting on the tank.
Water is delivered to the oil tank along with the heating oil fuel: This is not common, but it is possible to get a delivery of "bad" heating oil that is water contaminated,
especially if the oil truck happens to fill-up at the oil storage depot when an oil barge is
unloading oil since during that operation water which is normally kept in the bottom of oil depot
storage tanks may be stirred-up.
Most oil companies know to avoid this problem and some also have water
filters installed at their oil trucks. No oil company is going to admit that they picked up and delivered
water-contaminated oil to your home so don't waste time asking them if they are guilty of this crime.
How to Measure the Level of Water Contamination in an Oil Tank
Assess the amount of water in the oil tank (which could have come from condensation, leaks into the tank,
or from deliveries of bad oil containing water) by:
Sources for Water Finding or Water Indicating Pastes
Water finder paste for use in heating oil tanks: using a water finder paste on the end of a stick.
Water indicating paste also called water finding paste or water finder paste, is coated over the bottom few inches of an oil tank probing stick or onto a string or flexible tape which can be inserted into an oil tank. The water indicating paste changes color (typically white to red, green to red,or pink to white)
to indicate the depth of water in the oil tank.
You can ask your oil company to handle this if you don't have a stick, string, or tape or tools to open an access plug on the top of your oil tank.
This method works best if the oil filler pipe is a straight shot down into the oil tank, If there is not sufficient
overhead room to insert the long stick, such as with outdoor and buried oil tanks you'll need to use a string or tape which you coat with the water indicating paste.
Here is a list of water and oil indicating pastes that will detect water in home heating oil tanks whether they are buried or above ground, outside, or indoor tanks:
Eastern Water Indicating Paste (in a tube, turns red in presence of water)
Eastern Oil Indicating Paste (oil finding paste) in a jar, used to indicate the height of heating oil, diesel oil, kerosene, gasoline, etc, turns from pink to white).
Kolor Kut water Indicating Paste
Sar-Gel gauging paste turns bright red where it contacts water
McCabe Gauging Paste - a water level indicating paste, turns from green to red when immersed in water for 30 seconds or more. McCabe also makes a gasoline indicating paste which is purple and shows a line where gasoline is encountered.
Here are some online sources where you can purchase these products (we have no financial relationship with any product or service discussed at our website:
www.marineservicesinc.biz/ - Marine Services, Inc.
Other Methods for Detecting Water Contamination in a Heating Oil Tank
Other water sensing products: Other special products are available such as a sensor connected to a
string or wire that can be dropped into an oil tank to check for water contamination. Water alarm devices
are also available.
Visual Check of the oil filter at the oil burner: inspecting in the oil filter at the heating equipment can indicate a history of
water passing from the oil tank towards the oil burner. Water in the oil filter, or rust therein, would be an
indicator of water passing through the system.
Ask your oil company service technician to check the oil filter for evidence of water or rust,
or if you've had heat outages ask if water in the oil could be a contributor or cause.
See TEST FOR WATER
for additional discussion of methods of testing for water in oil storage tanks.
How to Remove Unwanted Water from an Oil Tank
Small amounts of water contamination in an oil tank
can be absorbed by alcohol products and moved through the heating system
by adding "4 in one hot" or similar additives available from HVAC suppliers or through your oil company.
Small amounts of water contamination in an oil tank can be removed from the oil tank using products like
the H2O Water Worm from H2O Control Products, Inc.
Quoting from the company's product literature: The H2OWater Worm is a 36" x 1.5" cloth tube containing a small amount of our water absorbing desiccant.
You simply drop the Water Worm into the tank via any convenient opening, being sure to hold onto the attached 7' string. Secure the string outside of the tank. After settling to the bottom of the tank, the Water Worm will absorb any water that collects or has collected in the tank.
To check or remove the sock, simply use the attached string to pull the Water Worm out. If it is full and firm, it's spent; if not, put the Water Worm back in to collect more water. [Photo courtesy of H2O Control Products Inc.]
Pump Out Large amounts of water in an oil tank such as several inches or more in the tank bottom
(water will stay at the bottom of the tank as water and oil don't mix), have to be pumped out by your oil company.
(They will leave the heating oil behind and intact). Simply call your oil delivery company or heating service company to arrange for them to check and pump water out of the tank. It's a straight-forward procedure that most oil companies know quite well.
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OIL TANK TESTING Oil Tank Testing Methods & Choices BURIED OIL TANKS, FINDING How to Find Buried Oil Tanks OIL TANK FAILURE CAUSES Oil Tank Leaks or Oil Tank Failure Causes - oil tank leaks are caused by corrosion, damage, soil conditions, other factors TANK FAILURE RATES Oil Tank Failure Rates - Oil Tank Leak Probability as a Function of Tank Age, Location, Condition, Soil Conditions and Other Factors
More Information on Building Diagnostic Inspections and Repairs
Oil Tanks - The Oil Storage Tank Information Website: Buried or Above Ground Oil Tank Inspection, Testing, Cleanup, Abandonment of Oil Tanks
Abandon a Buried Oil Tank, How To - Abandoning Commercial Underground Tanks, Russ Brauksieck, ASHI Tech. Journal, Vol.3 No.1 Spring 1993, P. 40-41 [Reprint]
Buried Oil Tanks - Finding How to Find Buried Oil Tanks and "Nearly Hidden" and Leaky Oil Tanks - photos and text.
Buried Fuel tank - Advice - Buried FUEL Tank - GAS or OIL advice for home buyers, home owners, inspection report language for homes where a buried oil tank is or was installed
Petroleum Bulk Storage J. Sibblies, NY State DEC, Advice to Home Owners and Home Inspectors about Oil Storage Tanks - summary from ASHI Chapter Seminar.
Septic Tank inspection, testing, diagnosis, repair
OIL TANK FAILURE CAUSES - Oil Tank Failure Causes - oil tank leaks are caused by corrosion, damage, soil conditions, other factors
Tank Failure Rates - Oil Tank Failure Rates - Oil Tank Leak Probability as a Function of Tank Age, Location, Condition, Soil Conditions and Other Factors
OIL TANK TESTING - - How Oil Tanks are Tested for Evidence Leaks, of Current or Previous Oil Spills
"How do you choose the right tank testing method?", Cynthia Johnson, Fuel Oil & Oil Heat Magazine, November 1995
.
National Association of Oil Heat Service Managers, PO Box 380, Elmwood Park, NJ 07407
"Homeowners Guide to Fuel Storage," Agway Energy Products, Verbank, NY, November 1990
Web Link Exchange: Contact Us to list your website or contact information for oil tank testing, tank corrosion research, oil industry experts
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Home Inspection Report Language Library: Buried Oil Tanks, Buried or aboveground oil tank advice for home buyers and home owners, where a buried oil tank is or was installed, also home inspection report language for oil tanks
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