Though specific regulations for oil tank installation in relation to property boundaries vary from region to region, a good rule of thumb to follow is if the tank is less than 3500 litres, it should not be placed within 760mm of a combustible boundary e.g. a fence, assuming that there are no outlets or buildings between the tank and the boundary.
In addition to this, oil tanks cannot be installed closer than 1.8 meters to the property or any extensions of property, including eaves, sheds, and gazebos. These regulations are put in place to help prevent the spread of fire to all properties within proximity of the oil tank.