CENEX PIPELINE LLC

Incident Narrative

ON MARCH 27TH, A POTENTIAL LEAK WAS IDENTIFIED AT BLOCK VALVE 251.6 (LOCATED NEAR WEST FARGO, NORTH DAKOTA, N 46.89783 W 96.90347) DURING A ROUTINE BLOCK VALVE INSPECTION BY AN OPERATOR QUALIFICATION (OQ) QUALIFIED EMPLOYEE. INSPECTION PERSONNEL IMMEDIATELY NOTIFIED CENEX MANAGEMENT WHO MOBILIZED THE INCIDENT COMMAND POST AND INITIATED RESPONSE ACTIONS. THE LINE SEGMENT WAS NOT IN OPERATION AT THE TIME OF INSPECTION BUT THE LINE SEGMENT WAS IMMEDIATELY ISOLATED BY CLOSING THE NEAREST UPSTREAM AND DOWNSTREAM BLOCK VALVES. CENEX RESPONSE PERSONNEL AND CONTRACTORS WERE DISPATCHED TO THE AREA TO ASSESS THE SITUATION. AIR MONITORING ACTIVITIES INDICATED A PETROLEUM HYDROCARBON RELEASE HAD OCCURRED. BLOCK VALVE 251.6 WAS EXPOSED BY EXCAVATION ON MARCH 28TH. RESPONSE PERSONNEL IDENTIFIED A DAMAGED INJECTION PORT FITTING ON THE VALVE BODY THAT RESULTED IN THE RELEASE. THE FITTING IS PART OF A FACE SEAL INJECTION SYSTEM THAT IS BUILT INTO THE VALVE. THE SUBJECT FITTING IS A THREADED FITTING ORIGINALLY INSTALLED BY THE VALVE MANUFACTURER. DESCRIPTION OF VALVE AND MAINLINE BLOCK VALVE 251.6 IS A CAMERON T31 FULL WELDED BODY BALL VALVE. THE CENEX 8' MAINLINE WAS CONSTRUCTED IN 1991 AND TRANSPORTS REFINED PETROLEUM PRODUCTS FROM MINOT, ND TO RECEIVING FACILITIES LOCATED IN WEST FARGO, ND. THE PIPELINE PRIMARILY CONSISTS OF 8.625' (OUTSIDE DIAMETER) PIPE WITH A 0.188' WALL THICKNESS, GRADE API 5L X-52. MAINLINE OPERATIONAL PARAMETERS THE PIPELINE SEGMENT FROM MINOT TO FARGO OPERATES INTERMITTENTLY. ALL BLOCK VALVES ON THE SEGMENT ARE OPERATED AND INSPECTED, IN ACCORDANCE WITH PART 195.420, A MINIMUM OF ONCE EVERY SIX MONTHS NOT TO EXCEED SEVEN AND ONE HALF MONTHS. LINE PRESSURES FROM MINOT TO FARGO TYPICALLY RANGE FROM 500-1,000 PSI. VALVE REPAIR THE VALVE HAS BEEN REPAIRED BY OQ QUALIFIED PERSONNEL WITH THE INTENT OF REPLACING THE VALVE WITH A NEW, ABOVE-GROUND ASSEMBLY. THE DAMAGED FITTING WAS REMOVED FROM THE VALVE AND THE PORT PLUGGED WITH A NEW THREADED PLUG. ALL EXPOSED PIPING, IN ADDITION TO THE VALVE AND APPURTENANCES, WAS INSPECTED PER PART 195.569 AND FOUND TO BE IN GOOD CONDITION. ALL PIPE COATINGS WERE INTACT AND FREE OF SIGNS OF CORROSION. THE SUPPLEMENTAL REPORT REFLECTS A TIME ZONE CORRECTION TO ALIGN THE REPORT WITH THE TIME ZONE TO THE LOCATION OF THE INCIDENT.