Section 160.200  Diking

a)         Individual tanks or groups of tanks, where deemed necessary by the Office of the State Fire Marshal on account of proximity to waterways, character of topography, or nearness to structures of high value, or to places of residence or public assembly, as defined in 41 Ill. Adm. Code 100.30, shall be diked or the yard shall be provided with a curb to prevent the spread of liquid onto other property or waterways. Where a diked enclosure is required under this paragraph, the volumetric capacity of the diked area shall be not less than the aggregate capacity of the tanks within the diked area, or be in accordance with NFPA 30 (1981) Section 2-2.3.3.b.

b)         Sufficient distance to meet the requirements of Sections 160.200, 160.220 and 160.230 shall always be allowed for the building of a dike at such time as a dike may be required by subsection (a) above.

c)         Distance from the tank shell to the toe of the dike shall be not less than five feet.

d)         The product stored within a diked area must not be of a type that would be incompatible with other products in the event of a fire.  Alcohol must be separately diked from gasoline or other petroleum products.  Petroleum products containing less than 10% alcohol by volume shall be treated as petroleum for the purpose of this Section.

(Source:  Amended at 9 Ill. Reg. 10012, effective October 1, 1985)