Reasons an oil tank might leak
Oil tanks can leak for a variety of reasons; the most common are:
- failures of the tank body
- damage to equipment on the tank such as sight gauges
- damage to or wear-and-tear of fuel feed lines
- failure of components at the boiler end of the system, such as flexible hoses
Metal tanks can rust through, often at their bases. Plastic tanks can split due to inherent defect or age/wear-and-tear and spills can occur when oil is delivered.
Who is responsible
Anyone who uses, stores, fills, transports or manufactures hazardous substances, such as oils, has a responsibility to make sure the substance is contained and used in a way that won’t result in a release to the environment. They also have a responsibility to clean-up any spills that occur and deal with any consequences of the release.
Whether you own or occupy premises that have a domestic oil tank, you’re advised to check with your insurance company that you have adequate home insurance in place to cover costs associated with all aspects of the assessment and clean-up of a spill, and any consequences of migration of the spill through the ground.
What to do if there's a spill or a leak
If you suspect an oil leak at your home, you should act quickly and contact your insurance company. Don’t put off taking action or assume the problem will go away. The quicker the leak can be dealt with, the less oil will be lost and further damage can be minimised.
If your building and contents policy permits, your insurance company will appoint a specialist contractor on your behalf. If your insurance doesn’t provide adequate cover, you will need to call the UK Spill Contractors Accreditation Scheme or use the International Spill Accreditation Association (ISAA) website to find a local contractor.
- phone UK Spill Contractors Accreditation Scheme: 0333 444 1890
- International Spill Accreditation Association (ISAA) website
- Contacting 08 and 03 numbers
Once you have appointed a contractor, follow these steps:
- if there’s a strong smell of oil in your home, ventilate the area by opening windows and doors and contact the Environmental Health Department at your local Council for advice
- keep children and pets away from any spills
- avoid getting oil on your skin and clothing
- wash your hands and don’t smoke, eat or drink when or after you are in contact with the oil
- switch off your oil supply at the tank
- try to find out where the leak is coming from
- immediately, try to stop it at the source - put a bucket under dripping oil to catch it (don’t use containers that will be used to store food for humans or animals)
- prevent spilled oil from spreading and, in particular, prevent it from getting into drains and waterways - you can use absorbing material such as earth, sand, cat litter or commercial products
- if there’s an ongoing leak from the tank, try to stem the flow - you may be able to use sealant to temporarily repair a metal tank; for plastic tanks, try rubbing a bar of soft soap into the split
- try to work out how much oil has been lost; check the level on the tank and think about how much you use and when you last had a deliver
- never use detergents or a hose to wash the spill away
- store anything with oil on it, or soaked into it, in containers that don’t leak until it can be correctly and legally disposed of
- if the oil has or could enter drains or the water environment (groundwater, ponds, burns, rivers, loughs, estuaries or coastal waters) you must contact the Northern Ireland Environment Agency immediately on their water pollution hotline
- if it’s likely to affect a public water supply you must contact Northern Ireland Water on their Waterline number
- if it’s likely to affect private water supplies you must contact your local Council (ask for the Environmental Health Department)
- if your water supply or pipework may have been affected, don’t drink the water
- arrange for any remaining fuel in the tank to be removed by a fuel supplier -don’t try to do this yourself and don’t store oil in a building, shed or vehicle
- check with your insurer whether they or you should arrange for an engineer to repair or replace your tank or pipework (note damaged plastic tanks can’t be repaired)
If the spill has contaminated the ground, the soil will need to be cleaned up along with any floating oil and any affected waterways.
Clean-up works will generally only be carried out by specialist environmental contractors. If your building and contents policy permits, your insurance company will appoint a specialist contractor on your behalf.
However, if you don’t have the necessary insurance cover, you will need to appoint a specialist contactor yourself. Unless your spill is a minor spill, don’t try to clean-up the oil yourself, given the potential health risks and the specialist nature of remediation and waste disposal.
You or your contractor will need to contact NIEA for advice on the safe disposal and/or treatment of contaminated soils or waters.
Minor spills or major spills
To work out whether the spill is a minor one or a major one, ask yourself the questions below:
- is there a strong smell of oil indoors?
- has the oil spread away off your land, under your house or down a drain?
- are there any burns, ponds, loughs or drains, or private water supplies in the immediate area?
If the answers to the above questions are no and you are sure that the spill is recent, small and limited to shallow soil, then it counts as a minor spill and you can follow the advice below on cleaning up minor spills. However if the answer to any of these questions is yes or you aren't sure about whether it was recent, small and limited to shallow soil then you may be dealing with a more major spill.
Clearing up minor spills
You can clear up clearly confirmed minor spills yourself though you may prefer to use a contractor. In order to do so follow the steps below:
- check the soil, working out from the source of the spill to find where the oil now is
- if the oil is limited to a few buckets worth of soil then dig up the oily and stained soil, remove the oil and dispose of the soil correctly
- if the oil has spread to more soil than that then follow the advice for a major spill instead
- make a note of anything you've done in clearing up the spill and take photos
Clearing up major spills
It is not recommended that you clear up more major spills yourself. A specialist contractor should be appointed to make all the necessary investigations and do any clearing up and disposal.
Making sure it doesn't happen again
You can minimise the risk of a spill happening again by following tips on checking your oil tank regularly on the Check your oil tank page.