Underground Heating Oil Tanks: A Homeowner’s Guide

While most home heating oil tanks are not regulated by the State – typically they are not over 1,100 in capacity, some delegated counties have regulations that apply to smaller heating oil tanks. If you live in one of the 5 delegated counties, you are encouraged to contact the county agency to determine whether such smaller tanks are regulated.

Even if your heating oil tank is unregulated, you probably know that a leak could be very unfortunate – not only for the environment, but for your pocketbook too. When an underground tank or pipe leaks, the cleanup can cost $20,000 or more. And if your homeowner’s insurance policy contains a “pollution exclusion” clause, which many do, you could get stuck with the bill.

When a tank is found to be leaking, additional work is usually needed to determine the extent of the problem and the amount of cleanup required. Contamination must be reported to the Spills Hotline by calling 1-800-457-7362.

The best way to avoid significant expenses is to replace your underground tank or have a new aboveground tank installed in your basement, garage or storage shed. You probably have questions about what this would involve. This guide has been prepared to give you answers and advice.

Why should I consider replacing my underground tank?

Like all equipment, tanks have a limited useful life and eventually have to be repaired or replaced. Moreover, many underground home heating oil tanks are like the 275-gallon bare steel tanks you have seen in basements or garages. These tanks were not designed to be buried and, if left in place, will eventually rust and leak. Even larger tanks that were specifically designed for underground use can leak if they are not protected from rusting.

If you notice an unexplainable increase in your home heating oil use, your tank may be leaking. But that information alone is not always an accurate indicator. In some cases, water may leak into the tank, or the leak may occur only when the tank is full, thus hiding the problem from the homeowner.

Odds are an underground tank 10 or 15 years old is probably not leaking, but the likelihood of a leak increases as the tank gets older. Even small, slow leaks can pose a serious threat to your family, your neighbors and the environment if they go undiscovered for a long time. And, if your tank does leak, you may face a costly cleanup. Having an old tank replaced with a modern double-walled underground tank or basement tank can save you both money and anguish in the long run. Don’t forget, piping should also be replaced when a new underground tank is installed. Contract with a reputable equipment dealer to be sure the tank is installed with overfill alarms, vents and other vital equipment items.

How much does it cost to remove an underground tank?

As of April 1997, removal contractors were generally charging between $500 and $2,500 depending on the size of the tank, its condition, and how easily it can be reached. Usually not included in this price are the cost of a replacement tank, sampling and testing, cleanup work if a leak is found, and landscaping after the removal is complete.

For the best price, shop around. Check the yellow pages and contact your oil company. Get cost estimates from several contractors. They can provide you with an accurate estimate only by visiting your home to determine both where your tank is located and whether there are obstacles to getting the job done. Compare services and be sure to check references. As with any substantial home improvement, get a written cost estimate and a contract that outlines the services to be performed before work begins.

Can I test my tank for leaks instead of digging it up?

Yes, by all means test your tank and piping for tightness, but it may cost you less to simply remove your tank from the ground. It is important to consider that no test can predict what will happen next year, next month, or even the next day. If you have an old bare steel tank, your money may be better spent on tank removal since you will have to dig the tank up anyway if the test reveals it is leaking.

Although a commercial tank tester provides the most reliable check for leaks, the handyman can obtain a gross check for a leak by checking for a drop in the oil level in the tank when oil is not being consumed. Information on testing methods can be obtained from DEC by calling (518) 402-9543 or companies that perform tank tests.

Can I just empty the oil from my tank and leave it underground?

Yes, provided certain other measures are taken.

In 1996 the Legislature passed a state law requiring that aboveground and underground heating oil tanks be emptied, cleaned and purged of all vapors. If the tank is to be removed, the vent line and fill line must also be removed or the fill line must be capped with concrete. If the tank is to be left in place, the vent line must remain open and intact and the fill line capped or removed.

Local government can only approve the abandonment if written proof is provided that the tank has been properly abandoned. Call your local building department for assistance.

The best choice is to remove the tank. This will enable you to check for soil contamination and avoid future sink holes which might occur when the tank eventually collapses.

In addition, should you decide to sell your home, a bank or the buyer may ask for environmental testing or the removal of the tank, which could make leaving your tank in place costlier than taking it out of the ground at the start.

How will I know if my tank has leaked?

Contamination may be indicated by signs of a damaged tank or pipe, soil that is stained or gives off strong oil odors, a sheen on the groundwater, or environmental test results. Sampling and analysis are recommended if the tank is located near any wells, drinking water supplies, wetlands, ponds or streams, or if there are any indications that contamination is present.

When shopping for a contractor, ask if they have the capability of doing an environmental assessment.

What if contamination is found?

First, don’t panic. The problem could be minor and relatively simple
to correct. Take cleanup actions right away. Addressing the problem now will prevent higher cost and damage later.

If you find contamination or even suspect there has been a leak, contact the nearest DEC regional office or call the Spill Hotline
(1-800-457-7362). DEC will provide you with guidance and assistance.