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Why Are There So Many Hidden Oil Tanks Around Vancouver?

Before 1970 most homes in and around Vancouver were heated with oil, and to keep these large eyesores hidden from sight, the tanks housing heating oil were buried underground. Once we began to phase out oil in favour of electricity or natural gas, these tanks were generally left in place; some were decommissioned and others were forgotten about completely. Years later, unsuspecting homeowners are still dealing with the repercussions of these buried oil tanks.

What Happens When an Oil Tank is Found?

Because of the potential environmental and safety hazards buried oil tanks pose, lenders, insurers, and realtors often require oil tank certificates before approving mortgages, issuing policies, or finalizing property sales. Ground-penetrating radar (GPR) scans are frequently used to detect these underground tanks in these situations because they provide accurate, non-invasive results, helping to confirm the tank’s presence without excavation.

If an oil tank is uncovered the solution is almost always to have the tank removed; however, there are special situations where a tank may have to be decommissioned and left in place.

Oil Tank Found Away from Permanent Structures

Oil tanks are most commonly uncovered within 10 feet of the home and not more than 2 to 5 feet underground. This allowed for easy access to the home’s heating system while keeping the tank hidden from view. If an oil tank is found in this area, regardless of whether it’s now underneath a driveway, patio, or your prized rose garden, it must be removed. The reason for the strict policy on underground oil tanks is the risk of soil and groundwater contamination, which has devastating environmental consequences. In these cases, even though removal may be inconvenient, the benefits far outweigh the costs.

Oil Tank Buried Underneath a Permanent Structure

The only situation where a permit may be issued to partially remove or abandon an underground oil tank rather than removing it entirely is when the tank is located underneath a permanent structure—typically the main dwelling—and removal would compromise the structural integrity of the building. In this scenario, you still can’t leave the tank untouched; the tank must still be safely decommissioned following strict environmental guidelines to minimize any potential risks. However, the process will look a little different.

Decommissioning an oil tank located underneath a permanent structure requires the help of not only an oil tank removal team but also input from a certified structural engineer.

Working together, any accessible parts of the oil tank will be removed and the space filled to maintain structure integrity. Soil samples from the area will be taken to ensure there has been no oil contamination; if samples return results above the legal limits set by the Ministry of Environment, additional soil remediation will be required.

Why Can Previously Decommissioned Oil Tanks be Left in Place?

In some cases, a GPR scan may turn up a previously decommissioned oil tank. While it may seem logical to leave these tanks in place, regulations still require decommissioned oil tanks to be fully removed. This is because when the first oil tanks were decommissioned, there was very little oversight or guidelines to follow, resulting in tanks that were not properly cleaned, backfilled, or inspected, leaving the risk of contamination or other hazards.