Advice: Make sure your oil tank is well maintained

Gareth Thompson, Environmental Health Officer, explains: “Over the last few years, there have been an increasing number of pollution incidents caused by faulty or badly maintained domestic central heating oil tanks. In one case, the oil supply pipe between the tank and the house developed a leak. Heating oil contaminated the ground beneath a neighbour’s house. The neighbour’s house had to be evacuated as it was uninhabitable and the floor completely removed to deal with the contaminated ground.

“I am also aware of another problem where a central heating oil tank mounted on concrete block supports corroded over time. Oil leaked out of the tank, staining the supports and soaking into the ground below. Water pipes to two houses ran under the spill area. As oil can penetrate plastic water supply pipes, there was a serious risk of the water supply being contaminated. The water pipes had to be replaced and the contaminated soil removed.”

He added: “These incidents cost several thousands of pounds to rectify and caused considerable stress and disruption to the residents. You should review your home insurance policy to make sure you are covered for oil leaks or spills.”

Here are some indications that you may have a problem and steps you can take to try and prevent problems occurring:

• Look out for a strong smell of solvent, petrol or oil inside or outside your home or in your cupboards. This, combined with black stains and dead plants or grass around your tank, could indicate a leak.

• Monitor and become familiar with your normal usage of oil. If you’re using more than normal, check for leaks immediately. There have been instances where people have re-filled a leaking oil tank without checking when their last delivery was, without realising that they were doubling the amount of oil lost. The more oil lost, the more difficult and expensive it is to clean up.

• Check the condition of your tank regularly. If it’s a metal tank, ensure it’s painted regularly to avoid the metal corroding.

• If possible, supervise any deliveries of oil. Make sure you don’t order more oil than you can fit into your tank.

• Have a thorough and regular maintenance check carried out by a competent person on your whole heating system, not just the boiler.

• Keep fill points on the tank clear of obstructions and ensure they are tamper proof.

• If your tank is not bunded, consider building one. A bund is a collection trough which sits under the oil tank. If a tank leaks, all the oil will be retained within this leak proof trough. The bund should have the capacity to hold at least 10% more than the capacity of the tank (as it can collect rainwater over time). Bunds can be built of brick, concrete or other watertight material. From time to time you may need to empty rainwater out of it, but do not be tempted to fit a drain hole, unless fitted with a tap which can be securely closed. Some designs of tank incorporate a bund. The tank has a second skin which acts a safety net if the tank leaks.

Gareth concluded: “If you suspect you have a leak it’s important to find out where the leak is coming from. Switch off your oil supply at the tank and arrange to have it emptied (if needed) and arrange for an engineer to repair or replace your tank or pipework. Prevent the spill from entering drains by blocking its flow using earth, sand or commercial products that absorb oil - never use detergents or a hose. Keep your home well ventilated by opening windows and doors and call your insurance company or landlord to make them aware that there is a leak. If you think it could affect a stream, pond or water supply call the Emergency Oil Care Hotline on 0800 807 060.

“The Environmental Health team is also on hand to help at any time. If you have a strong smell of oil in your home or would like some further information call 028 9034 0160. Please, don’t put off taking action or assume the problem will go away.”