Section 203.1390  Stack in Existence

"Stack in existence" means that the owner or operator had begun, or caused to begin, a continuous program of physical on-site construction of the stack or entered into binding agreements or contractual obligations, that could not be cancelled or modified without substantial loss to the owner or operator, to undertake a program of construction of the stack to be completed within a reasonable time.

(Source:  Added at 49 Ill. Reg. 6237, effective April 23, 2025)