ENTERPRISE PRODUCTS OPERATING LLC

Incident Narrative

A THIRD PARTY CALLED OPERATION CONTROL (OC) REPORTING A VAPOR CLOUD NEAR THE WEST BANK OF THE CHARITON RIVER. OC SUBSEQUENTIALLY CLOSED THE NEAREST UPSTREAM REMOTE BLOCK VALVE, NOTIFIED THE COUNTY SHERIFF DEPARTMENT, AND NOTIFIED FIELD OPERATION PERSONNEL TO INVESTIGATE AND CLOSE THE NEAREST MANUAL VALVES. THE LINE WAS ISOLATED AND DEPRESSURIZED, AND OTHER AGENCIES AND NRC WERE NOTIFIED. AS A PRECAUTIONARY MEARSURE, THE SHERIFF DEPARTMENT EVACUATED 16 HOMES. A PRECISE COUNT OF NUMBER OF PEOPLE EVACUATED WAS NOT MADE BUT ALL WERE CLEARED TO RETURN TO THEIR HOMES WITHIN SEVERAL HOURS. AFTER THE AREA WAS MADE SAFE, THE LINE WAS EXCAVATED AND EXPOSED IN PRESENCE OF A PHMSA CENTRAL REGION INSPECTOR. THE LINE WAS THEN CUT AND REPAIRED WITH PRE-TESTED PIPE. THE FAILED PIPE WAS SENT TO KIEFNER AND ASSOCIATES FOR METALLURGICAL ANALYSIS. THE KIEFNER ANALYSIS IDENTIFIED THE ROOT CAUSE AS ""DOWNHILL SOIL SETTLEMENT"" RESULTING IN A BENDING MOMENT ACTING ON THE PIPE THAT RESULTED IN PROPAGATION OF A CIRCUMFERENTIAL CRACK THAT CAUSED THE LEAK. UNDER APPROVAL OF PHMSA CENTRAL REGION, THE LINE WAS RESTARTED ON APRIL 2 WITH A TEMPORARY 20% PRESSURE REDUCTION. SUBSEQUENT TO DETERMINATION OF CAUSE OF THE FAILURE AND REVIEW OF FOLLOW UP INVESTIGATIVE DIGS, PHMSA CENTRAL REGION APPROVED RETURNING THE LINE TO THE OPERATING PRESSURE ESTABLISHED PRIOR TO THIS IN-SERVICE FAILURE. JULY 6, 2012 - MINOR CHANGES TO THE FINAL REPORT INDICATED IN A.7, A.17 (16 INDICATES THIS WAS HOMES NOT INDIVIDUALS), E.5.A, E.5.B, AND E.5.C.