CENEX PIPELINE LLC

Incident Narrative

CENEX WAS IN THE PROCESS OF INSTALLING BURIED VALVE LEAK MONITORING SYSTEMS ON THE BURIED CAMERON VALVES WITHIN THIS SEGMENT, WHEN A POTENTIAL LEAK LOCATION WAS IDENTIFIED AT BV 185. THE PIPELINE WAS SHUTDOWN AT THE TIME THE POTENTIAL RELEASE WAS IDENTIFIED AND CENEX INITIATED EMERGENCY RESPONSE UPON MAKING THE DISCOVERY. ON JUNE 8TH, CENEX COMPLETED EXCAVATION OF BV 185 AND FOUND THE DOWNSTREAM SEAL INJECTION PORT WAS THE SOURCE OF THE RELEASE. CENEX KEPT THE MINOT TO FARGO LINE SHUTDOWN UNTIL THE REMAINING PLANNED VALVE LEAK MONITORING SYSTEMS WERE IN PLACE AND THE LEAKING INJECTION PORT ON BV 185 WAS PLUGGED WITH A NEW THREADED PLUG. THE REPORT REQUIRED OPERATORS TO SUBMIT UPSTREAM AND DOWNSTREAM VALVES USED TO ISOLATE THE RELEASE. FOR THIS RELEASE, ONLY THE UPSTREAM VALVE AT MP 175.9 WAS USED TO ISOLATE THE RELEASE BECAUSE THE DOWNSTREAM PIPING DRAINS AWAY FROM MP 185.6 AND WAS LEFT OPEN TO PULL PRODUCT AWAY FROM THE RELEASE SITE. CHS ANSWERED REMOTE BECAUSE THE REMOTE VALVE AT FARGO, DOWNSTREAM OF THIS LOCATION WAS CLOSED AT THE TIME OF THE RELEASE. NOTE - THE DISTANCE REPORTED BETWEEN VALVES IS THE DISTANCE FROM THE UPSTREAM VALVE AND THE RELEASE SITE.