Fuel oil spills can ruin a life-long investment

Clean-ups are expensive. Many oil spills could be avoided through regular inspection and maintenance.

Oil spills are a significant source of pollution, especially in rural areas. A fuel tank leak or oil spill can cause extensive soil and groundwater contamination resulting in expensive clean-up costs. A five litre spill can contaminate one million gallons of potable water to the extent that petroleum odours can make the water unfit for consumption.

The number of residential fuel oil leaks and spills has increased in recent years and has the potential to become much larger as tanks and oil lines reach the end of their lifespan. Tanks can last a long time but not forever. The likelihood of an oil leak occurring increases when storage tanks and fuel oil lines are over 30 years old or have not been properly maintained. When purchasing an older home, determining the age and condition of a fuel oil tank can be difficult. Unless the tank is tagged or there is a record of a tank change, the tank may be as old as the house.

According to recent statistics, hundreds of residential fuel oil spills occur every year in Ontario and the numbers could be in the thousands nationwide. Depending on specific site conditions, the costs of cleaning up these spills can range anywhere from a few thousand dollars to several hundred thousand dollars.

Residential heating oil spills occur for a number of different reasons. Defective or missing vent whistles and broken or damaged fuel level gauges are the two main reasons for tank overfills and oil spills in basements during fuel oil deliveries. Copper fuel oil lines installed under concrete floors can corrode and cause significant pollution problems. Leaking underground oil lines are difficult to detect and can go unnoticed for many years. If condensation accumulates on the inside of a tank over a period of time, the tank can fail suddenly, and without warning, as a result of internal corrosion.

What can be done to minimize the risk of a spill? Storage tanks, oil lines and entire heating systems should be inspected periodically by a qualified service person. Many spills occur each year as a result of tank supports failing which can damage the tank on impact or result in damage or complete separation of the fuel oil supply line or filter assembly. Plastic fill or vent pipes must never be used as they can break or shatter in cold weather.

Cracked or broken fuel level gauges should be repaired immediately and defective vent whistles should be replaced. Small oil stains under tanks could indicate a loose line connection or problems with seams or welds. Dampness along the bottom of a tank could indicate bigger problems and this condition should be further investigated. Stained soils or dead grass below fill pipes could indicate chronic environmental problems. To reduce the possibility of internal corrosion, oil tanks should be filled at the end of each heating season. Installing used oil tanks should be avoided as the history and true condition of the tank will likely be unknown.

To prevent "overpressurization" of a tank, the vent pipe must be large enough to safely vent the tank while it is being filled. Insufficient venting could cause the fuel level gauge to "pop" out of the tank as it is being filled or oil could back up through the fill pipe and spill on the ground.

Removing oil tanks from basements and leaving the fill and vent pipes in the wall has caused many basements to be accidentally filled with oil. Always notify the fuel oil distributor when tanks are removed and cancel future oil deliveries. Documenting this is always a good idea.

For outside storage tanks, the tank must be on a solid footing to avoid a tank rollover. If there is a danger of ice or snow falling on the tank or fuel oil line, consideration should be given to moving the tank or protecting the exposures. When tanks are located near wells, rivers, or lakes, a spill containment device should be installed under the tank to minimize the migration of any spilled oil.

What can be done to minimize the financial effects of residential heating oil spills? Clearly, not all residential heating oil spills are caused by driver error or oil company negligence and the responsibility for cleaning up a spill could be the sole responsibility of the homeowner. Some insurance policies specifically exclude pollution coverage for leaks or spills from residential heating oil tanks. Homeowners should check with their agent or insurance company to see if there is pollution coverage because sooner or later it's going to happen again, and someone will have to pay.

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