1. a) The bases of tanks which are more than one foot above the ground shall have a firm foundation and supports of non-combustible materials. Footings shall be below the frost line.
2. b) Unprotected steel as a support for tanks shall not be permitted.
3. c) No combustible materials shall be permitted under or within 10 feet of any storage tanks. Stairways to and walks on top of tanks shall be of iron or steel.

4. d) Tanks installed after July 1, 1985 shall have 12" diameter culvert pipe sumps installed as follows: Within a dike, these sumps shall be as remote from each other as possible considering drainage, topography, and other factors as may appear to effect the ability of the sump to recover the product.

   Up to 500,000 gallons	One sump
   500,001 gallons to 1,000,000	Two sumps
   1,000,001 or more	Four sumps

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