TRANSCONTINENTAL GAS PIPE LINE COMPANY
gas_transmission Incident — — February 18, 2025
Incident Information
| Incident Date | February 18, 2025 |
| Operator | TRANSCONTINENTAL GAS PIPE LINE COMPANY |
| Commodity | NATURAL GAS |
| Pipeline Type | gas_transmission |
Location
| State | |
| Coordinates | 36.65607, -77.65957 |
Cause
| Cause | MATERIAL FAILURE OF PIPE OR WELD |
| Subcause | ENVIRONMENTAL CRACKING-RELATED |
Casualties
| Fatalities | 0 |
| Injuries | 0 |
Costs
| Property Damage | $222,000 |
| Emergency Response | $19,863 |
| Other Costs | $0 |
Location Map
Incident Narrative
"OPERATIONS DISCOVERED GAS LEAK AT MP 97.15 ON SVL-T-T-T WITH HANDHELD LEAK SURVEY EQUIPMENT. AFTER CONFIRMATION, LINE PRESSURE WAS REGULATED TO 80% OF OPERATING PRESSURE AND EXISTING PRESSURE WAS DRAWN DOWN BY A DOWNSTREAM CUSTOMER. AFTER EXCAVATION, A TRANSVERSE CRACK WAS VISUALLY IDENTIFIED ON THE PIPE BODY. THE LINE WAS SUBSEQUENTLY ISOLATED, FURTHER DRAWN DOWN BY CUSTOMERS WITH REMAINING PRESSURE BLOWN DOWN. THE PIPE SEGMENT WAS THEN CUT OUT AND REPLACED WITH PRETESTED PIPING. THE CUTOUT PIPE WAS SENT TO A METALLURGICAL LAB FOR ANALYSIS. LAB ANALYSIS CONCLUDED THE FOLLOWING: THE PRIMARY FAILURE MECHANISM WAS STRESS CORROSION CRACKING (SCC), DRIVEN BY RESIDUAL TENSILE STRESSES FROM PREEXISTING BENDING DURING CONSTRUCTION IN COMBINATION WITH A MILDLY CORROSIVE, OXYGEN-DEPLETED ENVIRONMENT. SCC MAY NOT HAVE OCCURRED IN THE ABSENCE OF PIPE BENDING DURING CONSTRUCTION, HIGHLIGHTING THE CRITICAL ROLE OF MECHANICAL LOADING IN THIS FAILURE. UNINTENTIONAL LOSS VOLUME WAS UPDATED AND REDUCED AFTER FURTHER ANALYSIS."
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.