Leaking oil tanks: What you need to know
What can I expect to pay to remediate an oil tank leak on a property?
- The average cost for cleaning up a residential heating oil tank ranged $7,000 to $15,000 dollars.
- In many cases, homeowners insurance will NOT pay for the remediation costs.
Most homeowners have heard stories about leaking oil tanks & the impact the cleanup process has had on their properties. If you do have an oil tank leak, the cleanup process does not have to be a major project. This section will give you background about oil tank leaks, why they occur and most importantly what to expect during the leaking oil tank cleanup process.
What is an oil tank leak?
- An oil tank leak usually refers to the escape of petroleum from a buried tank. Underground tanks are designed to hold 250 to 1,000 gallons of heating oil based on the tank size. Oil tank leaks usually start out as a very small hole in the tank structure which causes the tank's contents to leach into the surrounding soil sometimes at depths exceeding 10 feet. If there is a leak, the tank will need to be removed and the soil will require remediation. Unfortunately, leaks in the oil tank cannot be repaired, and the tank must be removed in order to clean up the surrounding soil.
- Faulty or corroded fuel lines can be another reason why oil may be present in the soil. If the oil contamination is not extensive, the fuel lines, unlike the tank itself, can be repaired.
- While it is true above ground tanks can leak as well, they present less of a problem because the tank metal can be easily examined for flaws by visual inspection and can be repaired before the fuel escapes the above ground tank.
Why do buried oil tanks leak?
- Most buried oil tanks are made of bare steel. When these tanks are placed underground, the steel may react negatively to the surrounding soil. Over time, this soil to steel reaction can start a corrosion process which wears away the tank metal over time. This is how pinholes form in the steel and the tank develops leaks in its structure.
How do I know if I have a leaking oil tank?
- A tank test or soil test will be the most reliable way to find out if your oil tank has a problem. A tank tightness test will evaluate whether the tank structure has a leak but will not be able to identify whether oil has escaped into the surrounding soil. A soil test can determine whether oil has leaked into the soil but works most reliably when the soil tested is taken from below the tank bottom.
- There are other less reliable methods that may indicate a problem with the oil tank. Oil odors inside the home can be one indication. Dead vegetation in the yard where the oil tank is buried can be another indication.
- If the home has a sump pit, the homeowner should regularly examine any water in the sump for evidence of oil. You can do this by using a clear glass jar to sample the water. If there's oil in the water sample, it will always float to the top because oil is lighter than water. The presence of heating oil in the sample means there is a high possibility your oil tank may be leaking.
If my buried oil tank leaked, how is the cleanup process handled? What can I expect?
The cleanup process should be performed by a state certified tank removal contractor. You may be surprised to find out dealing with an oil tank leak is a relatively simple process.
- The contractor will start by removing the tank. The entire removal process should be complete in a few hours.
- The contractor will verify by visual inspection that the oil tank leaked heating oil into the surrounding soil. Regardless of the amount of fuel present in the soil, the contractor will call the state and report a fuel spill. The state will assign a case number.
- The next step should involve determining whether the heating oil tank leaked fuel into the water the table. If the water table is impacted, homeowners insurance may cover the cost to remediate the tank. In most cases, the contractor can make this determination on the same day as the tank removal.
- If the water table is involved in the cleanup, the homeowner will be instructed to contact their insurance company. At this point, the burden falls on the insurance company to verify the policy covers this event. This usually means an adjuster is sent to examine the property and review the contractor's findings. Most likely, the contractor will need to return to the property on another date to finish the remediation.
- If an oil tank leak is discovered during the removal process or there is a question about insurance coverage, the contractor will need to come back another day to complete the cleanup. The company should not leave your home in an unsightly condition. Typically, a tarp is placed on top of the contaminated area along with any available clean soil that has been excavated. All equipment should be removed when the contractor leaves for the day.
- As long as an insurance adjuster does not need to visit the site, the contractor can return in a day or two with several loads of back fill. The contractor will use a backhoe or similar machine to dig through the contaminated area until clean soil is reached. When the area is visibly clear of oil contamination, the soil is analyzed on-site to verify compliance with state remediation standards.
- The same day, you can expect the contractor to fill the entire area with clean soil and restore the property to the same level you would expect in a standard tank removal job.
- After the oil tank leak is cleaned up, the tank removal contractor will file state paperwork and obtain a no further action letter. This letter should be stored with all the home's important documents.