Underground Oil Tanks

Environmentally, it is important that underground oil tanks be removed. Eventually they may rust and allow residual oil to leak into the soil. This oil can travel a long way with time, contaminating soil for a considerable distance from the source.

Financially, it is important because the cost of removing an underground oil tank and rehabilitating contaminated soil can easily reach into the tens of thousands of dollars if the tank has leaked.

And the homeowner is responsible for the entire cost!

Victoria area homes built in the 1960’s or earlier were often heated by oil stored in tanks buried in the ground.  As many of these homes converted to gas or electric heat, these tanks were occasionally left buried in the ground. Sometimes the oil was pumped out and the tank filled with sand and then covered with dirt.  Other times, the tank was simply abandoned and remained buried.  Homes from this era should be carefully checked to see if a tank is still present.

Underground storage tanks may be mentioned in municipal or fire department records. We use our contacts at the municipalities and fire departments to see if they have useful information. This record check is included as part of our underground oil tank scan. Sometime archived Multiple Listings reports mention oil tanks and we attempt to check these as well. Properties where a history of UST removal and certification is not available from the homeowner or municipality should be checked.  A Ground Penetrating Radar (GPR) scan helps determine the possibility of buried tanks and can indicate areas where tanks may have been removed.

Meadowvale inspectors scan the property using Ground Penetrating Radar (GPR) – the most reliable and accurate instrument available for detecting the presence of underground oil storage tanks. Details on how GPR can be used to locate an underground tank can be found in some of the FAQ’s lower on this page.

In addition to GPR, two additional pieces of equipment are used to assist in locating underground tanks:

A Magnetic Locator is a device which detects ferrous metals exclusively. It will not detect non-ferrous metals such as aluminum, brass or copper. The benefits of a ferrous metal locator is that it will not register ‘false positives’ caused by non-ferrous metals and will detect ferrous metals to a much greater depth than an all-metal detector. Depending on its mass, the magnetic locator will detect a ferrous metal target to a depth of 30 feet or more. Targets are limited to ferromagnetic materials—iron, steel and alloys.

An Inductive Pipe Locator is a device which passes an alternating electric current to a pipe, creating a magnetic field around the pipe. An electromagnetic sensor above the ground detects the induced magnetic field and allows the operator to track the location and depth of the pipe under the ground. This is particularly helpful when an oil fill line is present, but it can also work by inducing a current even if no direct connection to a pipe is possible.

These three pieces of equipment, when used by an experienced operator, enable the inspector to detect and locate underground oil storage tanks with a high degree of accuracy.

Ground Penetrating Radar uses a device which radiates short pulses of high-frequency electromagnetic energy into the ground from a transmitting antenna.  When a wave encounters a new material, such as an oil tank buried in the ground, a portion of the energy is reflected back to the surface. This reflected energy is detected by a receiver antenna and transmitted to a control unit for processing and display. Analysis of the reflective pattern allows the operator to detect the underground oil tank.

Use of ground penetrating radar will provide the most accurate results when searching for underground oil tanks.   Other devices, while helpful in a search,  all have serious limitations which do not allow them to provide the high degree of certainty possible with GPR.

GPR has many other uses as well (archeological exploration, construction industry, forensic searches, etc.) For more details, check out this Wikipedia page.

While GPR doesn’t actually “see” below the surface, the signal can penetrate 50 feet or more in dry, granular rocks and sediment. The top of most tanks are located within 8 feet of depth.

Yes.
The GPR signal penetrates those surfaces and the tanks can be detected by the operator.

No.
The terms “Ground Penetrating Radar” and “X-Ray” are sometimes incorrectly used interchangeably. But they are not the same thing and they do not describe the same process. For example, the construction industry may use X-Ray scans when examining concrete slabs in multi-story structures such as apartment buildings and parking garages. But X-Ray scans require physical access to both the top and bottom of the substance being scanned. Therefore it cannot be used to find underground oil tanks.

Local municipalities have different regulations regarding oil tanks. You can check their policies by visiting the municipal websites. If you are looking at a property outside the areas below, call your municipal office for information.

City of Victoria
Municipality of Saanich
Oak Bay Municipality
Esquimalt Municipality
Town of View Royal
City of Colwood

The scan is done at the same time as the home inspection. So you will know if a tank is present when you receive your inspection report. A scan does not delay your report in any way.

Yes and No.
The tank may have leaked prior to removal. If the Seller can provide you with a report documenting the tank removal and soil testing for contamination was completed, then you should be fine.

No.
Meadowvale Home Inspections does not remove tanks or test the area for contamination. We will be pleased to point you in the direction of reliable companies who are experts in removal and soil remediation if a tank is found on your property.

$100 – when performed as part of a home inspection on the same property. We do not perform oil tank scans on homes we do not inspect.