ENERGY TRANSFER COMPANY

Incident Narrative

ETC EXPERIENCED A RUPTURE ON THE 36"" OASIS PIPELINE IN A RURAL (CLASS I) AREA IN AUSTIN COUNTY, TX ON JULY 28, 2010. THE LINE IS AN INTRASTATE NATURAL GAS TRANSMISSION PIPELINE UNDER THE JURISDICTION OF THE TEXAS RAILROAD COMMISSION. THE INCIDENT WAS REPORTED TO THE TRRC UNDER INCIDENT ID: 551 AND ALSO TO THE NRC UNDER ID: 949134. THROUGH A THOROUGH EXAMINATION, BY THIRD PARTY, KIEFNER & ASSOCIATES, AND THROUGH MAG-PARTICLE TESTING, STRESS CORROSION CRACKING (SCC) WAS DETERMINED TO HAVE BEEN INVOLVED. METALURGICAL LAB ANALYSIS WILL BE PERFORMED ON THE FAILED SECTION OF PIPE AND WILL PROVIDE FURTHER DETAILED INFORMATION. TO DATE, ETC HAS COMPLETED HYDROSTATIC TESTING OF APPROXIMATELY 30.5 MILES WITHIN THE AREA OF THE INITIAL IN SERVICE FAILURE. THE TESTING CONSISTED OF FOUR TEST SECTIONS RUNNING EAST TO WEST FROM THE BRAZOS RIVER (STA. 2950+00) TO 4.5 MILES WEST OF MLV2 (STA. 4560+00). EACH TEST SECTION WAS TESTED TO A MINIMUM OF 100% SMYS FOR ONE HOUR AND THEN A SUBSEQUENT LEAK TEST AT 90% SMYS FOR A MINIMUM OF 8 HRS WITHOUT PRESSURE LOSS. SECTION 1 AND 4 SUCCESSFULLY PASSED THEIR INITIAL TESTS, SECTION 2 HAD TWO FAILURES AND SECTION 3 HAD 3 FAILURES BEFORE ACHIEVING A SUCCESSFUL TEST. IT SHOULD BE NOTED, THAT OF THE 5 FAILURES THAT OCCURRED DURING THE TESTING, THE MINIMUM FAILURE PRESSURE OCCURRED AT 84% OF SMYS INDICATING THERE WERE NO OTHER CRITICAL CRACKS THAT WOULD HAVE FAILED AT OPERATING PRESSURE. BASED ON THE RESULTS OF THE HYDROSTATIC TESTING, AND INTEGRATION OF INFORMATION OBTAINED FROM THE RUPTURE SITE, SOIL RESISTIVITY SURVEYS AND SUBSEQUENT EXCAVATIONS, ETC FEELS THAT ALL OF THE SCC COLONIES OF A CRITICAL SIZE WERE LOCATED WITHIN THE SECTION OF LINE BETWEEN MLV1 TO MLV2. PLANS ARE TO REINSTORE SERVICE ON OR AROUND SEPTEMBER 1, 2010 AND SUBSEQUENTLY RUNNING THE EMAT CRACK DETECTION TOOL FROM OUR PRAIRIE LEE COMPRESSOR STATION TO KATY, APPROXIMATELY 113 MILES, TO FURTHER CONFIRM OUR FINDINGS AND FURTHER DEVELOP OUR OVERALL MITIGATION PLAN FOR THIS THREAT. FINAL UPDATE 08/26/2013: AFTER A THOROUGH METALLURGICAL EXAMINATION, PERFORMED BY KIEFNER AND ASSOCIATES, INC, THE FAILURE WAS MOST LIKELY DETERMINED TO BE CAUSED BY HIGH PH TYPE SCC IN THE BODY OF THE PIPE. THIS DETERMINATION WAS BASED UPON PIPE-TO-SOIL POTENTIAL, SOIL RESISTIVITY, AND PH MEASUREMENTS AS WELL AS METALLOGRAPHIC SECTIONS THROUGH ADJACENT IN THE COLONY