The Control of Pollution (Silage, Slurry and Agricultural Fuel Oil) Regulations (Northern Ireland) 2003

2.  The fuel oil storage area shall be surrounded by a bund capable of retaining within the area –

(a) in a case where all the fuel oil within the storage area is contained in one fuel storage tank, a volume of fuel oil not less than 110 per cent of the capacity of the tank;

(b) in a case where all the fuel oil within the storage area is contained in more than one fuel storage tank, a volume of fuel oil not less than whichever is the greater of –

(i) 110 per cent of the capacity of the largest tank within the storage area; and

(ii) 25 per cent of the total volume of such oil which could be stored in tanks within the area;

(c) in any other case, a volume of fuel oil not less than whichever is the greater of –

(i) 110 per cent of the capacity of the largest container within the storage area; and

(ii) 25 per cent of the total volume of such oil at any time stored within the area.