35 Ill. Adm. Code 721.275
Secondary Containment
Section 721.275 Secondary Containment
a) Container
storage areas must have a secondary containment system that is designed and
operated in accordance with subsection (b).
b) A secondary containment
system must be designed and operated as follows:
1) A
base must underlie the containers which is free of cracks or gaps and is
sufficiently impervious to contain leaks, spills, and accumulated precipitation
until the collected material is detected and removed;
2) The
base must be sloped or the secondary containment system must be otherwise
designed and operated to drain and remove liquids resulting from leaks, spills,
or precipitation, unless the containers are elevated or are otherwise protected
from contact with accumulated liquids;
3) The secondary
containment system must have sufficient capacity to contain ten percent of the
volume of containers or the volume of the largest container, whichever is
greater;
4) Run-on
into the secondary containment system must be prevented unless the collection
system has sufficient excess capacity in addition to that required in
subsection (b)(3) to contain any run-on which might enter the system; and
5) Spilled
or leaked material and accumulated precipitation must be removed from the sump
or collection area in as timely a manner as is necessary to prevent overflow of
the secondary collection system.