NORTHERN ILLINOIS GAS CO — Integrity Assurance Notification

PROGRAMPursuant to 49 C.F.R. § 192.909, the purpose of this notification is to make you aware of a significant change to our Integrity Management Plan (IM Plan). Nicor Gas has added the potential threat of stress corrosion cracking (SCC). While Nicor Gas has not previously considered SCC as a potential threat, our Southern Company Gas affiliated utility, Atlanta Gas Light, has identified SCC on a pipeline in Georgia.#