GENESIS PIPELINE USA, L.P.

Incident Narrative

A GENESIS PIPELINE OPERATOR CONTACTED MANAGEMENT AT 11:33AM THAT WHILE DOING A VALVE INSPECTION ON VALVE 4505.5(MANUAL VALVE - 24"" THROUGH-CONDUIT GATE VALVE), A LEAK OCCURRED FROM A PRESSURE RELIEF PORT ON THE UPPER PORTION OF THE VALVE BONNET. THE PRESSURE RELIEF IS A PLUG TYPE WITH A SET SCREW IN THE MIDDLE. OIL BEGAN LEAKING FROM THE SET SCREW FOLLOWING ~ 20 TURNS WHILE ATTEMPTING TO CLOSE THE VALVE 25% FOR AN INSPECTION. THE SOURCE WAS CONTROLLED BY CLOSING MOV 4803 AND MOV 4806. AT 1:00 PM, THE SET SCREW WAS TIGHTEN AND THE PIPELINE WAS READY FOR SERVICE. A CALCULATION OF 17 GALLONS WAS DETERMINED AS THE QUANTITY OF THE LEAK ONTO THE GRAVEL AND DIRT. OSRO WAS CALLED IN AND CLEAN-UP EFFORTS BEGAN APPROXIMATELY AT 3PM. SUPPLEMENTAL: AN INTERNAL INVESTIGATION DETERMINED THAT THE REASON FOR THE LEAK AT THE SET SCREW ORIFICE WAS THAT AN UNKNOWN FORCE CAUSED THE SET SCREW TO PULL OUT SLIGHTLY FROM ITS TIGHTENED POSITION SOMETIME BETWEEN INSTALLATION AND 1/26/15. THE INVESTIGATION TEAM CONCLUDED THAT THERE WAS INSUFFICIENT EVIDENCE TO NARROW DOWN ONE POTENTIAL CAUSE FROM ANOTHER AND AS SUCH EVERY POSSIBILITY WOULD BE SPECULATIVE. GENESIS HAS TAKEN THE PRUDENT APPROACH TO REVIEW THE CURRENT PROCEDURES FOR VALVE MAINTENANCE AND TO MAKE CORRECTIONS THAT MAY INCLUDE VERIFICATION THAT THE SET SCREW IS TIGHT BEFORE OPERATING THE VALVE. SUPPLEMENTAL: 9/2/2016 CORRECTED PART D QUESTION 6 - MAPPING DATA SHOWS ACCIDENT OCCURRED NEAR HCA ZONE BUT DID NOT AFFECT IT.