The Home Guru: Debunking the Myths about 'Scary' Underground Tanks

Maybe it’s just that people tend to fear what they can’t see, but one of the most anxious moments I’ve observed among house hunters is when they learn that a home they like has an underground oil tank. And it happens quite often because, depending on which source is to be believed, as many as one-third to one-half of all homes in this region come with one.

Just the other day, the tension was palpable as a homeowner watched Anthony Cannizzaro, owner of American Tank & Line Testing since 1999, set up his equipment to conduct a “tightness” test for leaks on the underground oil tank located near a grouping of rhododendron near the back of the house to be sold. 

Although I was representing the buyers, the woman who owned the house leaned over and whispered to me, “Oh, my, I hear that 90 percent of these tests fail. I’m a nervous wreck.” 

I assured her that the percentage of failure was not that high, not that I‘m an expert by any means. But because I rely on the kindness of experts who tell me what I need to know to sound more  “Home Guru-ish,” I already had a less frightening estimation from an environmental scientist I know, Ed Townsend of Environmental Consulting and Management Services.

“The reality of the situation is that only about 25 percent of tests fail and usually the problem is not with the tanks, but rather the lines that serve them,” he had said, “And among those, only about 10 percent need to have the tanks replaced.” 

Further he noted that homeowners don’t test on a regular basis because it is not required by law in most municipalities, and buyers and sellers usually order a test only when a bank, mortgage company or insurance company requires it.

Cannizzaro agreed pretty much with the information I had. “Most times, nothing is known about the quality of a tank or when it was installed,” he said, further noting that, years ago, some builders installed cheaper quality tanks that featured steel walls that were only 1/8” thick and suited better for above-ground use. For underground use, promising a longer life, the higher grade would be 3/16” to ¼” thick.

Recently I had three transactions involving underground tanks. With one, where Cannizzaro was doing the test, the homeowners had no prior information about their tank, while with another sale, the homeowner produced a document from a tank testing and replacement service that certified that a double lined carbon steel tank wrapped in Fiberglas, considered all but indestructible, had been installed less than five years ago and had a 30-year warranty. That piece of paper greatly relieved the buyers and saved them at least $375, Cannizzaro’s cost, for a tank test. The third situation is that the tank was simply moved when it was discovered that it was on a neighbor’s property!

For testing an underground tank for tightness, Cannizzaro utilizes a “listening” system called the EZY3 Locator Plus. The boiler is shut down, along with the feed and return lines, and using a pump, a vacuum is then created within the tank and the lines. With the use of a microphone attached to earphones, the engineer can listen to know if air is getting into the system.

Cannizzaro says that if a hissing sound is heard, it’s above the line of the oil in the tank, and in most cases would signify that there is a leak in the line fixtures. If however, a bubbling sound is heard, that indicates that there is a leak below the product line, meaning that there is a hole or leak from the tank itself.

“People get scared to death because they’ve heard that removing a failed tank and the soil around it can cost $20,000 to $50,000, but that is very rarely the case,” he said. “Mostly it’s the linesand not the tank that are failing the tests and they just need to be replaced or retightened,”

If contamination is found through borings, the soil must be removed to the extent necessary and sent to a facility where t is incinerated to burn off the hydrocarbons orcontaminants,  Then, it can be eused as fill.

Replacing the tank if there is no soil contamination, depending on the amount of work to be done, can range from a few hundred dollars to an average of about $3500 for tank replacement.

For homeowners who want to feel more confident about the condition of their underground tanks, it would be well worth the $375 spent on a tank test, especially before a home is placed on the market.

Bill Primavera is a Residential and Commercial Realtor® affiliated with Coldwell Banker, a publicist and a journalist who writes about homes. Visit his website at www.PrimaveraRealEstate.com and, if you would like to consult with him about buying or selling a home, contact him directly at 914-522-2076.