EXXONMOBIL PIPELINE CO

Incident Narrative

ON MAY 5TH AT 13:32 HRS. EXXONMOBIL PIPELINE COMPANY (EMPCO) OCC RECEIVED A CALL FROM A THIRD PARTY PIPELINE COMPANY NOTIFYING EMPCO OF AN AREA OF DEAD VEGETATION OBSERVED ON THE EMPCO ROW. EMPCO RESPONDED TO THE SITE AND BEGAN EXCAVATING TO INVESTIGATE. ON MAY 5TH AND 6TH, EMPCO EXCAVATED IT'S PIPELINE BUT OBSERVED NO ACTIVE LEAK. TO CONFIRM LINE INTEGRITY, EMPCO PERFORMED A STAND-UP TEST ON THE EXCAVATED PIPELINE AT 175 PSI, AND AGAIN NO LEAK WAS OBSERVED. AS A FURTHER PRECAUTION, EMPCO CONTINUED OBSERVING THE EXCAVATED PIPELINE AS PRESSURE WAS GRADUALLY INCREASED. AT APPROXIMATELY 750 PSI, A PINHOLE WEEP WAS OBSERVED IN A PREVIOUSLY INSTALLED REPAIR SLEEVE WELD. THE WEEP WAS LOCATED ON THE LONGITUDINAL WELD ON THE REPAIR SLEEVE. EMPCO UPDATED THE NATIONAL RESPONSE CENTER AND THE TEXAS RAILROAD COMMISSION WITH THE RESPONSIBLE PARTY AND A CONSERVATIVE ESTIMATE OF SPILL VOLUME. THE AFFECTED PIPELINE SECTION WAS DISPLACED, REPAIRED, AND RETURNED TO SERVICE. SUBSEQUENT ANALYSIS, UTILIZING PRODUCT CONCENTRATIONS IN COMPOSITE SAMPLING OF REMOVED SOILS AND PRODUCT VOLATILIZATION/VAPORIZATION ESTIMATION, INDICATED A TOTAL ESTIMATED SPILL VOLUME OF LESS THAN 0.5 BARRELS. THE PREVIOUS REPAIR SLEEVE WAS INSTALLED PRIOR TO THE FIRST ILI RUN ON THE PIPELINE WHICH WAS ON MARCH 31, 2004. THE REMOVED REPAIR SLEEVE WAS SENT FOR EXAMINATION OF FAILURE. THE FAILURE WAS DETERMINED TO BE CAUSED BY INADEQUATE PENETRATION OF THE LONGITUDINAL SEAM WELD ON THE TYPE B SLEEVE. A CRACK FORMED AND GREW TO FAILURE THROUGH FATIGUE. . 8/17/18 AT PHMSA'S REQUEST, PART G, APPARENT CAUSE WAS UPDATED FROM ""OTHER INCIDENT CAUSE"" INDICATING A FAILURE ON A PREVIOUS REPAIR SLEEVE; TO A ""MATERIAL FAILURE OF PIPE OR WELD""; INDICATING A FAILURE ON THE PREVIOUS REPAIR SLEEVE WELD. CONSEQUENTLY, AS PART OF THIS CHANGE, PART G5 QUESTIONS 1-8 WERE COMPLETED AS REQUESTED. ADDITIONALLY, AT PHMSA'S REQUEST, PART C QUESTION 3 WAS CHANGED FROM ""REPAIR SLEEVE OR CLAMP"" TO ""WELD, INCLUDING HEAT AFFECTED ZONE"".