"Nonattainment New Source Review permit" or "NA NSR permit" means a permit or a portion of a permit for a new major source or major modification that is issued by the Agency under the construction permit program required by Section 9.1(c) of the Act that has been approved by USEPA and incorporated into the Illinois SIP to implement the requirements of section 173 of the CAA and 40 CFR 51.165. [415 ILCS 5/3.298]

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