ENTERPRISE PRODUCTS OPERATING LLC

Incident Narrative

ON DECEMBER 27, 2011, AT APPROXIMATELY 9:30PM, PIPELINE CONTROL (PLC) MADE NOTIFICATION TO TEXAS NGL PERSONNEL OF A SUSPECTED LEAK ON THE RIO GRANDE PIPELINE BETWEEN LAWSON JUNCTION AND DELAWARE STATIONS. PLC INDICATED THE SUPERVISORY CONTROL AND DATA ACQUISITION (SCADA) SYSTEM SHOWED A LARGE PRESSURE LOSS ON SEVERAL PRESSURE TRANSMITTERS. THE RIO GRANDE PIPELINE WHICH WAS CARRYING A PROPANE/BUTANE MIX (APPROX. 90% PROPANE/10% BUTANE) WAS SHUTDOWN AND ISOLATED. FIELD OPERATIONS PERSONNEL RESPONDED TO THE SUSPECTED LINE SEGMENT AND CONFIRMED A LINE FAILURE AT MILE POST 50.5 AT APPROXIMATELY 3:00AM DECEMBER 28, 2011. THE 8 INCH PROPANE/BUTANE PIPELINE HAD A COMPLETE WELD SEAM FAILURE, RESULTING IN RELEASE OF PROPANE/BUTANE TO THE SURROUNDING SOIL AND ATMOSPHERE. THE LINE SEGMENT WAS BLOCKED IN AT VALVES LOCATED AT MILE POSTS 47.7 AND MILE POST 58.8. FIELD OPERATIONS SECURED THE AREA, AND BEGAN TAKING STEPS TO CLEAR AND REPAIR THE LINE SEGMENT. THE RESIDUAL HYDROCARBONS WERE PURGED WITH NITROGEN FROM THE UPSTREAM AND DOWNSTREAM VALVE LOCATIONS. THE AREA WAS EXCAVATED WITH A BACK-HOE TO EXPOSE ENOUGH PIPE TO FACILITATE THE REPAIR. AFTER THE LINE WAS CONFIRMED TO BE FREE OF HYDROCARBONS, ONSITE CONTRACTORS (S&S CONSTRUCTION) PROCEEDED TO COLD CUT THE EAST SIDE OF THE LINE. THE FIRST COLD CUT WAS SUCCESSFUL AND APPROXIMATELY 20 FEET OF PIPE WAS REMOVED. TWO ENTERPRISE EMPLOYEES AND FOUR CONTRACTORS WERE IN THE TRENCH WORKING ON VARIOUS TASKS, SUCH AS REMOVING ADDITIONAL SOIL WITH SHOVELS, TAKING MEASUREMENTS AND EVALUATING THE AMOUNT OF ADDITIONAL PIPE THAT NEEDED TO BE REMOVED FROM THE WEST SIDE OF THE WELD FAILURE. AT APPROXIMATELY 5:00PM ON DECEMBER 28, 2011, A FLASH FIRE OCCURRED IN THE TRENCH WHEN A CONCENTRATION OF HYDROCARBONS EXCEEDING THE LOWER FLAMMABILITY LIMIT (LFL) FOR THE HYDROCARBON MIXTURE WAS IGNITED. FOUR INDIVIDUALS WERE IN THE PROXIMITY OF OF THE FLASH FIRE. ONE OF THOSE INDIVIDUALS REQUIRED OVER NIGHT HOSPITALIZATION.