PORTLAND NATURAL GAS TRANSMISSION SYSTEM — Integrity Assurance Notification

ECA MECHANICAL DAMAGE EVALUATIONThe purpose of this letter is to provide advance submission in accordance with §192.18 of TC Energy’s Dent Engineering Critical Assessment procedure developed in accordance with 49 CFR, §192.712(c)(11). This procedure utilizes the same ECA methodology as the TC Energy Special Permit Dent ECA procedure that was granted a letter of no objection by PHMSA on 6/15/2023. The draft procedure, TEP-IN-ECA-G Dent Engineering Critical Assessment Outside SP (US) will publish on February 1, 2024, and apply to the following TC Energy Pipeline Operating Systems. (See attached)#