GREAT LAKES GAS TRANSMISSION LIMITED PARTNERSHIP — Integrity Assurance Notification

PROGRAMIn accordance with 49 CFR 192.909(b) and 192.18, when an operator significantly modifies its Integrity management Plan (IMP), that substantially affects the program implementation, notification must be provided to the Information Resource Manager and to states with an interstate agent agreement. To that end, TC Energy (TCE) is providing notification that its gas pipeline IMP has been significantly modified as the result of improvements to our Stress Corrosion Cracking Threat Management Program resulting from the implementation of reliability-based analysis methods in our TEP-IN-EMAT-G Analysis of EMAT In-Line Inspection Technologies procedure (herein referred to as ‘Procedure’) for analyzing EMAT inline inspections (ILIs). The advantage of reliability-based analysis methods is they explicitly account for all input uncertainties and the level of safety (reliability) of the analysis is explicitly determined. Because of these advantages, reliability-based analysis methods are used in other high consequence industries such as the nuclear and aviation industries. As part of this change, additional reliability-based response criteria for EMAT ILIs have been added to our Procedure that are in addition to any current or upcoming crack ILI response criteria in accordance with 49 CFR 192.712, 192.714 and 192.933. With the implementation of reliability-based analysis methods, there are no changes to the proven fracture mechanic models (e.g., CorLas, API 579) used in the SCC Threat Management Program and associated Procedure for analyzing EMAT ILIs. Altogether, the proposed changes to the SCC Threat Management Program will improve the safety of TCE’s pipeline system through the addition of reliability-based response criteria and will continue to meet or exceed applicable regulatory requirements.#