DCP MIDSTREAM

Incident Narrative

AT APPROXIMATELY 4:10 AM AT DCP MIDSTREAM RAMSEY METER STATION LOCATED NEAR ORLA, TX, ONE OF THE RELIEF VALVES RELIEVED AT 1300 PSIG, VENTING APPROXIMATELY 473 BARRELS OF NGL TO ATMOSPHERE. MOP OF THE SYSTEM IS 1440 PSIG. DCP HCC RECEIVED THE FIRST ALARM AT 2:46 AM. AT 4:10 AM THE CONTROLLER NOTIFIED RAMSEY PLANT THAT THEY WERE SEEING GAS DETECTOR ALARMS. THE RAMSEY OPERATOR CONFIRMED VISUAL THAT THE RELIEF VALVE WAS VENTING AT 4:40 AM. DCP CONTROLLER INSTRUCTED RAMSEY OPERATOR TO CUT BACK ON THE FLOW TO LOWER THE PRESSURE ON THE SYSTEM. AT 6 AM DCP CONTROLLER NOTIFIED THE FIELD SUPERVISOR OF THE RELEASE. THE FIELD SUPERVISOR DISPATCHED FIELD TECHNICIAN TO THE SITE TO INVESTIGATE THE RELEASE. AT 6:38 AM DCP HCC NGL SUPERVISOR INSTRUCTED THE CONTROLLER TO SHUT DOWN THE MAGELLAN LATERAL. AT 9:40 AM NGL FIELD TECHNICIAN WAS ON SITE AND VISUALLY CONFIRMED THAT THE RELIEF VALVE WAS NO LONGER RELIEVING PRODUCT. HOWEVER, VISUAL INDICATORS CONFIRMED THAT A RELEASE HAD OCCURRED ON THE RELIEF VALVE. THE RELIEF VALVE WAS ICED OVER. AT 9:50 AM NGL HCC SUPERVISOR INSTRUCTED THE CONTROLLER TO START-UP THE MAGELLAN LATERAL. NGL FIELD TECHNICIAN WAS ON-SITE MONITORING FACILITY. THE INVESTIGATION DETERMINED THAT DCP WILL REMOVE THE RELIEF VALVE FROM THE CUSTOMER'S PIPING UPSTREAM OF THE DCP HIGH PRESSURE SHUTDOWN VALVE. RELIEF VALVE IS NOT NEEDED AT THIS LOCATION FOR PRESSURE CONTROL. SUPPLEMENTAL - 10/6/2014 RELIEF VALVE WAS REMOVED FROM UPSTREAM OF ESDV AND PRESSURE TRANSMITTER WAS RELOCATED FROM UPSTREAM OF ESDV TO DOWNSTREAM ON 8/4/2014. THE FIRE AND THERMAL EXPANSION RELIEF VALVES ON METER RUN WERE CHANGED OUT TO ANDERSON GREENWOOD'S AT THE SAME TIME FOR BETTER RELIABILITY.