Ill. Admin. Code tit. 83, § 501.20
This Part sets forth minimum requirements and shall apply to any natural gas public utility as defined in Section 3-105 of the Act and any alternative gas supplier as defined in Section 501.10. This Part shall not apply to any natural gas cooperative or to a municipal system when operating within its service territory. A public utility shall retain a record required by this Part for the period specified in 83 Ill. Adm. Code 510 unless this Part requires a longer retention period.
(Source: Amended at 41 Ill. Reg. 351, effective December 29, 2016)