a) Containment

1. 1) A base must underlay 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. 2) The base must be sloped or the 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. 3) When not protected from receiving precipitation, the containment shall have a minimum containment volume of a 6-inch rain storm (a 25 year, 24 hour rain), plus the capacity of the largest container, and the volume displaced by the bases of the other containers located within the secondary containment structure. Containers that do not contain free liquids need not be considered in this determination.
4. 4) When protected from receiving precipitation, the containment shall have a minimum containment volume of 100 percent of the capacity of the largest container, plus the volume displaced by the bases of the other containers.
5. 5) Run-on into the containment system must be prevented unless the collection system has sufficient excess capacity in addition to that required in subsection (3) above to contain any run-on which might enter the system.
6. 6) 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 collection system.

Container storage areas regulated under this Part must have a containment system that is designed and operated as follows:

b) Detection and Recovery of Releases

1. 1) Secondary containment systems must be:

   1. A) Designed, installed and operated to prevent any migration of materials or accumulated liquid out of the system to the soil, groundwater or surface water at any time during the use of the containment system; and
   2. B) Provide for detection and recovery of releases and accumulated liquids until the collected material is removed.

2. 2) To meet the requirements of subsection (a), secondary containment systems must be at a minimum:

   1. A) Constructed of or lined with materials that are compatible with the material(s) to be placed in the containment system and must have sufficient strength and thickness to prevent failure owing to pressure gradients (including static head and external hydrological forces), physical contact with the waste to which it is exposed, climatic conditions and the stress of daily operation (including stresses from nearby vehicular traffic);
   2. B) Placed on a foundation or base capable of providing support to the secondary containment system, resistance to pressure gradients above and below the system, and capable of preventing failure due to settlement, compression or uplift; and
   3. C) Sloped or otherwise designed or operated to drain and remove liquids resulting from leaks, spills or precipitation. Spilled or leaked material and accumulated precipitation must be removed from the secondary containment system within 24 hours, or in as timely a manner as is possible to prevent harm to human health and the environment, if the owner or operator demonstrates to the Agency that removal of the released material or accumulated precipitation cannot be accomplished within 24 hours.

c) Containment Runoff

1. 1) Uncontaminated storm water runoff must be removed from the secondary containment area within 24 hours after a precipitation event.
2. 2) Contaminated storm water runoff must be handled in accordance with 35 Ill. Adm. Code Subtitle C.

d) Special Requirements for Incompatible Materials

1. 1) Incompatible materials must not be placed in the same container.
2. 2) A storage container holding a material that is incompatible with any other materials stored nearby in other containers, piles, open tanks or surface impoundments must be separated from the other materials or protected from them by means of a dike, berm, wall or other device.

e) Condition of Container

If a container holding material is not in good condition (e.g., severe rusting, apparent structural defects) or if it begins to leak, the owner or operator must transfer the material from this container to a container that is in good condition.

f) Compatibility of Material With Container

The owner or operator must use containers made of or lined with materials which will not react with, and are otherwise compatible with, the material to be stored, so that the ability of the container to contain the material is not impaired.

g) Management of Containers

1. 1) A container holding material must always be closed during storage, except when it is necessary to add or remove material.
2. 2) A container holding material must not be opened, handled or stored in a manner which may rupture the container or cause it to leak.

h) Stacked Containers on Pallets

Containers must not be stacked more than two high on pallets.

i) Special Requirements for Ignitable or Reactive Material

1. 1) The material is stored or treated in such a way that it is protected from any material or conditions which may cause the material to ignite or react; or
2. 2) The container is used solely for emergencies.

Ignitable or reactive material must not be placed in containment systems unless:

j) Closure

At closure of a containment system, the owner or operator shall remove or decontaminate all residues, contaminated containment system components (liners, etc.), contaminated soils and structures and contaminated equipment.