Buried Oil Tank: Signs Your House Has One

A buried oil tank is common under the yards of older New Jersey homes. Many were left in the ground when the house switched to gas, and nobody wrote it down. Here are the signs worth checking, and why a sweep is still the only way to be sure.

Homes most likely to have a buried oil tank

• Built before about 1980, when buried steel oil tanks were common.
• Heated with oil now, or switched to gas or a heat pump at some point.
• In older neighborhoods where gas lines arrived late, which includes many South Jersey towns.

Newer homes are less likely to have one, though not impossible if the lot was built on before. If you're in the middle of a sale, read how buyers and sellers handle buying or selling a house with an oil tank in New Jersey.

Outside signs

• A fill pipe. A capped pipe, usually about 2 inches across, at or just above ground level near the house. It's where the delivery truck pumped oil.
• A vent pipe. A narrower pipe sticking up along the foundation, often with a mushroom-shaped cap.
• Cut-off pipe stubs. Pipes sawed off at grade, or hidden under mulch, a deck or new paving.
• Oil stains or odors. Stains on the foundation or an oily smell in the soil near the house.
• Odd low spots. A sunken patch in the lawn or driveway can mark where a tank was dug out, or where an old one is collapsing.

Inside signs

• Copper oil lines. Two small copper lines coming through the basement or crawl space wall, often cut, crimped or bent over.
• Lines in the floor. Pairs of small sealed pipes sticking up through the slab near where the old boiler or furnace sat.
• Patched holes. Patches in the foundation wall or floor where lines used to run.
• An old oil burner or gauge. Leftover equipment, or a removed boiler with the oil connection still visible.

How to find a buried oil tank for certain

Pipes get removed, buried and paved over, so a lot can look clean and still hide a tank. A tank sweep settles it. A technician scans the yard with a metal detector, and often ground penetrating radar, in about half an hour on a typical lot. It usually costs about $300 to $500 and isn't part of a standard home inspection. You can compare oil tank sweep and removal companies in South Jersey.

Book it at the start of your inspection period, at the same visit as the home inspection and radon testing for your South Jersey home sale. If a tank turns up, you need the rest of that window to get quotes. Our guide to oil tank removal cost in New Jersey shows what to expect.

Paperwork to check

• Old fuel oil delivery bills or a service contract.
• The seller's property condition disclosure, which asks about underground tanks.
• The town's construction office, which may have a permit on file if a tank was removed or closed.

If the seller says the tank was removed, ask for the town permit, the final inspection and the soil test results. "It was taken out years ago" isn't enough for a lender or a future buyer. The NJ Department of Environmental Protection's fact sheet on unregulated heating oil tanks lays out the required steps: a contractor certified for tank closure, a town permit, and a check for leaks when the tank comes out.