GAS TRANSMISSION NORTHWEST LLC
gas_transmission Incident —
Incident Information
| Report Date | — |
| Operator | GAS TRANSMISSION NORTHWEST LLC |
| Commodity | — |
| Pipeline Type | gas_transmission |
Location
| State | |
| Coordinates | 48.72929, -116.20183 |
Cause
| Cause | MATERIAL FAILURE OF PIPE OR WELD |
| Subcause | — |
Casualties
| Fatalities | 0 |
| Injuries | 0 |
Costs
| Property Damage | — |
| Lost Commodity | — |
| Public/Private Damage | — |
| Emergency Response | — |
| Environmental Remediation | — |
| Other Costs | — |
Location Map
Incident Narrative
ANALYSIS OF ILI DATA SHOWED AN INDICATION OF A DENT IN THE BOTTOM QUADRANT OF THE GTN A-LINE PIPELINE 447 FEET UPSTREAM OF MAINLINE VALVE MLV 3-1. A GROUND BASED LEAKAGE SURVEY WAS CONDUCTED AT THE SITE AND UPSTREAM AND DOWNSTREAM FOR A DISTANCE OF 300 FEET IN BOTH DIRECTIONS. GAS WAS DETECTED AT THE GROUND SURFACE NEAR THE LOCATION OF THE SUSPECTED DENT. THE PIPELINE PRESSURE WAS REDUCED AND THE PIPELINE SEGMENT WAS ISOLATED. PRESSURE REDUCTION WAS HELD BELOW 80% OF THE HIGHEST PRESSURE RECORDED DURING THE PREVIOUS 60 DAYS WHILE THE INVESTIGATION CONTINUED TO LOCATE THE POSITION OF THE LEAK. AFTER THE LOCATION OF THE LEAK WAS FURTHER LOCALIZED, THE PIPELINE SECTION WAS VENTED TO NEAR ATMOSPHERIC PRESSURE AND WAS HELD THERE UNTIL THE REPAIR PROCESS WAS BEGUN. FURTHER INVESTIGATION CONFIRMED A DENT WITH A CRACK NEAR THE BOTTOM OF THE PIPE. THE PIPE SECTION WAS CUT OUT AND REPLACED.
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.