Ill. Admin. Code tit. 35, § 845.310
a) Existing and new CCR surface impoundments, and all lateral expansions of CCR surface impoundments, must not be located in wetlands unless the owner or operator demonstrates the following:
2) The construction and operation of the CCR surface impoundment will not cause or contribute to any of the following:
3) The CCR surface impoundment will not cause or contribute to significant degradation of wetlands by addressing all the following factors:
C) The volume and chemical nature of the CCR;