MARATHON PIPE LINE LLC

Incident Narrative

ON 4/24/2010, OPERATIONS TECHNICIAN REPORTED A STAINED AREA (20' X 25') IN THE ZACHARY LOWER MANIFOLD BENEATH RETURN VALVE R12. LINE WAS NOT DELIVERING INTO THE STATION AT THE TIME, AND WAS NOT SCHEDULED TO TURN INTO THE STATION UNTIL 4/26/2010. PRELIMINARY INVESTIGATION REVEALED THAT THE 2"" SUMP DISCHARGE PIPING WAS CRACKED AT A THREADED TEE CONNECTION. THE 2"" SUMP DISCHARGE PIPING CONNECTS TO THE RETURN HEADER AND TO THE TRANSMIX LINE. THE 2"" CONNECTION THAT TIES INTO THE RETURN HEADER IS NORMALLY CLOSED AND THE 2"" CONNECTION THAT TIES INTO THE TRANSMIX LINE IS NORMALLY OPEN. THE HEAD PRESSURE FROM TANK 12 WAS PRESSURING UP THE SUMP DISCHARGE PIPING CAUSING PRODUCT TO ESCAPE FROM THE DAMAGED TEE CONNECTION. UPDATE - 8/12/2010 - THE TEE CONNECTION ALONG WITH A SECTION OF THE SUMP DISCHARGE LINE WAS SENT TO KIEFNER FOR FAILURE ANALYSIS. THE FAILURE WAS DUE TO DOWNWARD SETTLEMENT OF THE 2"" DRAIN LINE DOWNSTREAM OF THE TEE. KIEFNER INDICATED THAT THE SOURCE OF THE BENDING MOVEMENT WAS LIKELY RELATED TO THE RECENT CONSTRUCTION ACTIVITY.