NORTHWEST PIPELINE LLC — Integrity Assurance Notification

ECA MECHANICAL DAMAGE EVALUATIONThis notification, in accordance with §192.18 and 192.712(c)(11), is informing PHMSA of Williams’ intent to use an engineering critical assessment procedure following 192.712(c) for dents and other mechanical damage that meet Immediate, 1-year, or 2-year conditions as determined by §192.714 and §192.933. Upon approval from PHSMA, the attached procedure will be incorporated into Williams Procedures and referenced as an option to analyze dents and other mechanical damage features that are determined to be actionable by §192.714 and §192.933. Applicable Operator ID’s (all Williams’ OPIDs with 192 gas transmission pipelines): 12874, Mountain West Pipeline, LLC 13845, Northwest Pipeline 19570, Transcontinental Gas Pipeline 30826, Williams Field Services 30940, Williams Energy, LLC 31565, Gulfstream 31687, Hill Lake Gas Storage, LLC 32285, Worsham Steed Gas Storage, LLC 32374, Monroe Gas Storage Company, LLC 32375, Southern Pines Energy Center, LLC 32657, Cardinal Operating 32684, Pine Needle#