SHELL PIPELINE CO., L.P.

Incident Narrative

THE PIPELINE WAS ISOLATED BETWEEN MOV-34 AND MOV-39 DUE TO THE DISCOVERY OF AN LOPC ALONG THE ROW ON DECEMBER 21, 2020. THE EXPOSING OF THE PIPELINE REVEALED A PINHOLE LEAK LOCATED AT A GIRTH WELD IN THE SIX O' CLOCK (6:00) POSITION ON THE PIPE. SPLC HAS IMPLEMENTED SHEAR WAVE AND PHASED ARRAY METHODS OF NDE OF THE ANOMALY AND CONFIRMED THAT THE ISSUE IS ISOLATED TO A SINGLE PINHOLE LEAK AT THE GIRTH WELD. THE WELD DEFECT WAS NOT DETECTED THROUGH NDE DURING THE INITIAL CONSTRUCTION AND THE LEAK WAS SO SMALL THAT IT WOULD NOT BEEN DETECTED BY HYDROTEST. PERMANENT REPAIR HAS BEEN IMPLEMENTED BY THE INSTALLATION OF A PLIDCO-STYLE PRESSURE CONTAINING SLEEVE RATED FOR THE ANSI 600 SYSTEM. A LEAK TEST WAS PERFORMED ON THE REPAIR BY OPENING THE ISOLATION VALVES AND INTRODUCING LINE PRESSURE TO THE ANOMALY SITE. THE SLEEVE WAS VISIBLY MONITORED AND SNIFFED FOR THE PRESENCE OF HYDROCARBONS, AND NO EVIDENCE OF A LEAK WAS DETECTED. WITH THE SUCCESSFUL COMPLETION OF THE LEAK TEST, THE PIPELINE WAS TURNED OVER TO THE CONTROL CENTER (HCC) ON DECEMBER 23, 2020 FOR NORMAL OPERATION OF THE TLDS SYSTEM.