ONEOK WESTEX TRANSMISSION, LLC
gas_transmission Incident — — December 14, 2016
Incident Information
| Incident Date | December 14, 2016 |
| Operator | ONEOK WESTEX TRANSMISSION, LLC |
| Commodity | NATURAL GAS |
| Pipeline Type | gas_transmission |
Location
| State | |
| Coordinates | 31.98919, -102.48468 |
Cause
| Cause | EQUIPMENT FAILURE |
| Subcause | MALFUNCTION OF CONTROL/RELIEF EQUIPMENT |
Casualties
| Fatalities | 0 |
| Injuries | 0 |
Costs
| Property Damage | $0 |
| Emergency Response | $0 |
| Other Costs | $0 |
Location Map
Incident Narrative
ON 12/14/2016, AT THE RECENTLY CONSTRUCTED ECTOR COUNTY COMPRESSOR STATION, THE STATION EMERGENCY SHUTDOWN SYSTEM BLOW-DOWN VALVES OPENED UNEXPECTEDLY ALLOWING RELEASE OF NATURAL GAS TO THE STATION VENT LINE. GAS VENTED FOR AROUND 33 MINUTES UNTIL STATION ISOLATION VALVES WERE CLOSED TO SHUT OFF THE FLOW OF GAS FROM THE RED RIVER PIPELINE ALLOWING 12.89 MMCF TO VENT TO ATMOSPHERE. PARTIAL OPERATION OF THE VALVES HAS BEEN ATTRIBUTED TO A MOMENTARY LOSS OF OUTPUT FROM A DIGITAL OUTPUT CARD ON THE STATION PLC TO THE VALVES. THE STATION PLC PROGRAM WAS REVISED TO PREVENT THE RECURRENCE OF A PARTIAL ESD. ONEOK PERSONNEL FIRST BECAME AWARE OF GAS VENTING THROUGH THE STATION BLOW DOWN SYSTEM AT 12:59 PM. IT WASN'T UNTIL 14:28 THAT IT WAS DETERMINED THAT THE GAS RELEASE HAD EXCEEDED 3,000 MCF. DIFFICULTY IN ESTIMATING THE FLOW RATE DUE TO THE STATION BLOW DOWN PIPING CONFIGURATION WAS THE PRIMARY CAUSE OF THE DELAY.
About This Pipeline Incident
Pipeline incident data is reported to the Pipeline and Hazardous Materials Safety Administration (PHMSA). All significant incidents involving fatalities, injuries, or property damage over $50,000 must be reported.