1. a) Indoor facilities must comply with the following standards beginning two years after the date of first applicability:

   1. 1) The base of the facility must be constructed of materials capable of containing de-icing agents (e.g., bituminous or concrete pad).
   2. 2) The roof and walls of the facility must be constructed of materials capable of protecting the storage pile from precipitation and capable of preventing dissolved de-icing agents from entering into the adjacent soil, surface water, or groundwater. The walls of the facility must be constructed of materials compatible with the de-icing agents to be placed in the facility. Run-off from the roof must be diverted away from the loading pad.
   3. 3) All areas surrounding the storage pile, including the loading pad, must be routinely inspected to determine whether any release of de-icing agents has occurred. Such areas must be cleaned as necessary. Spilled de-icing agents must be placed back under the protective covering of the indoor storage pile. The storage pile must be reshaped as often as necessary to prevent leaching.
   4. 4) The integrity of the facility and loading pad must be maintained.
   5. 5) All areas surrounding the storage facility must be inspected daily to determine whether any release of de-icing agents has occurred. Spilled de-icing agents must be placed back into the storage facility.

2. b) Outdoor facilities or units must comply with the following standards beginning two years after the date of first applicability:

   1. 1) An impermeable membrane or cover must be placed over all storage piles to protect the piles from precipitation and surface water run-on. The membrane or cover must prevent runoff and leachate from being generated by the outdoor storage piles. The piles must be formed in a conical shape, covered, and stored on a paved pad capable of preventing leachate from entering adjacent soil, surface water, or groundwater.
   2. 2) Surface drainage must be directed to prevent flow through the base of the storage piles. De-icing agents must not be stored where drainage may enter into water supplies, farm lands, or streams.
   3. 3) All areas surrounding the storage piles must be cleaned and must be inspected daily to determine whether any release of de-icing agents has occurred. Spilled de-icing agents must be placed back under the protective covering of the outdoor storage piles. The storage piles must be reshaped as often as necessary to prevent leaching.
   4. 4) The storage piles must be designed and operated to control wind dispersal of the product by means other than wetting.

(Source: Amended at 47 Ill. Reg. 7581, effective May 16, 2023)