When you buy a home from me, we will discuss searching for an abandoned underground oil tank as part of your inspection process (in addition to a general home inspection, radon test, sewer scope, and other inspections that are available to you).
So what exactly is an abandoned oil tank? During the middle part of last century, a common type of fuel that was used in furnaces was oil. In order to have oil heat, you needed to have a way to contain the oil tank, which is what a tank was used for. Most commonly, these tanks were buried in the yard, but sometimes they were installed above ground, typically in the basement or side yard of the home.
When the homeowners decided no longer to use oil to heat their home (say, if they wanted to convert to gas) these tanks were simply abandoned in the yard. The oil was never pumped out of them. The typical life of these oil tanks was around 30 years before it would crack and start leaking into the ground, potentially damaging the groundwater and possibly leaking carcinogenic gas into the house itself.
Back in the late 90’s, searching for abandoned oil tank started to become an industry standard for inspections when buyers purchased a home. It is VERY common to find an abandoned oil tank, particularly with older homes.
When you are looking at a piece real estate, it is possible to see evidence of an abandoned oil tank on the property. Sometimes you will see a “fill pipe” or a “vent pipe” on the outside of the property, or about a four inch scar along the basement floor where oil lines ran to an old furnace. However, sometimes no evidence exists. You can do some homework searching the DEQ’s UST (Underground Storage Tank) database to see if any work has previously been done, or if your property is located in the City of Portland, you can search your property records at the city’s website Portland Maps (check the historic permits tab). However, often permits were not obtained and no records exist at all.
I had a property listed last year where we found no evidence of an oil tank upon visual inspection, but when the buyer did their professional inspections, an abandoned tank was indeed found. This abandoned tank contained several hundred gallons of oil at one time, and had been leaking for decades. It was a bad spill, and the cost to clean it up ran around $6,000, and my clients eventually decided to not sell the home and move into their dream home, partly because the repairs cost too much money, the oil tank being the biggest bill on the repair list.
Oil tank spills do not always cost that much (commonly in the $2,500 range). Rarely, they can cost considerably more if they’ve been leaking for even longer. There are times that the contaminated soil around the tank does not have to be physically removed, if the oil tank contractor can prove to the DEQ that the contamination does not threaten the groundwater and there aren’t carcinogens threatening the health of the occupants, among other criteria.
Occasionally you will find a home that still uses oil heat. The same concerns apply to working underground oil tanks as the ones that have been abandoned.
Searching for an abandoned oil tank costs in the vicinity of $75. Taking soil samples to find out if the tank has leaked is going to cost you around $200. These fees, while costly, could save you thousands of dollars in the future than if you had bought the house unknowingly with an abandoned tank.