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; and
(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.