"ONEOK NGL PIPELINE, LLC"
hazardous_liquid Incident — — June 23, 2019
Incident Information
| Incident Date | June 23, 2019 |
| Operator | "ONEOK NGL PIPELINE, LLC" |
| Commodity | HVL OR OTHER FLAMMABLE OR TOXIC FLUID WHICH IS A GAS AT AMBI |
| Pipeline Type | hazardous_liquid |
Location
| State | |
| Coordinates | 29.86739, -94.89550 |
Cause
| Cause | EQUIPMENT FAILURE |
| Subcause | THREADED CONNECTION/COUPLING FAILURE |
Casualties
| Fatalities | 0 |
| Injuries | 0 |
Costs
| Property Damage | $500 |
| Emergency Response | $5,000 |
| Other Costs | $8,000 |
Location Map
Incident Narrative
AT APPROXIMATELY 6:58AM ON 6/23/19 AN OPERATOR AT ONEOK'S MONT BELVIEU STORAGE FACILITY NOTICED A VAPOR CLOUD ON THE ODELL PUMP STATION CAMERA FEED. THE OPERATOR NOTIFIED ONEOK'S TULSA PIPELINE CONTROL CENTER OF THE OBSERVATION. AT 7:01AM A ONEOK OPERATOR VERIFIED THE VAPOR CLOUD ON-SITE. THE PIPELINE WAS SHUT DOWN AND THE LEAK WAS ISOLATED. AFTER EVACUATING THE LINE SECTION IT WAS DETERMINED THAT A CHECK VALVE ON THERMAL TUBING FOR A STATION VALVE HAD FAILED/BROKE. THE THERMAL TUBING AND CHECK VALVE WERE REPLACED AND THE SYSTEM WAS RETURNED TO SERVICE. THE BROKEN CHECK VALVE HAS BEEN SENT FOR METALLURGY ANALYSIS TO HELP DETERMINE THE CAUSE OF THE FAILURE. UPDATE: MATERIAL ANALYSIS INDICATED THAT THE FAILURE WAS DUE TO LOW STRESS HIGH CYCLE FATIGUE OF THE THREADS OF THE STAINLESS STEEL CHECK VALVE. SUPPLEMENT 9/10/19: PART G APPARENT CAUSE; MALFUNCTION OF CONTROL/RELIEF VALVE EQUIPMENT CHANGED TO THREADED CONNECTION/COUPLING VALVE THREADS DUE TO THE THREADS FAILING ON THE CHECK VALVE AND NOT THE ACTUAL CHECK FAILING. CHANGE MADE AT THE REQUEST OF PHMSA INVESTIGATOR.
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.