NORTHERN NATURAL GAS CO
gas_transmission Incident —
Incident Information
| Report Date | — |
| Operator | NORTHERN NATURAL GAS CO |
| Commodity | — |
| Pipeline Type | gas_transmission |
Location
| State | |
| Coordinates | 46.49600, -88.72990 |
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
A 157 PPM LEAK WAS INDICATED VIA AERIAL PATROL ON THE M433B WAKEFIELD-TO-MARQUETTE MAINLINE AT MILEPOST 63.57 ON 6/30/2022. ON 7/1/2022, A GRADE 3 LEAK WAS CONFIRMED AND THOUGHT TO BE FROM A FLANGED CONNECTION OF A STOPPLE FITTING. ON 7/5/2022, THE FLANGED CONNECTION OF THE STOPPLE WAS EXAMINED AND DETERMINED NOT TO BE THE SOURCE OF THE LEAK. IT WAS DETERMINED THAT THIS LEAK WOULD BE AN INCIDENT SINCE THE REPAIR COSTS WOULD LIKELY EXCEED THE $122K REPORTING THRESHOLD. THE LEAK WAS EXAMINED ON 7/13/2022. THE LEAK WAS ON A GIRTH WELD, WHICH WAS 8-1/2-INCHES DOWNSTREAM OF THE STOPPLE INSTALLED IN 2020. THE LEAK WAS IN THE CENTERLINE OF THE GIRTH WELD AT THE 5:00 POSITION AND WAS APPROXIMATELY 3-INCHES LONG. THE LEAK WAS SECURED WITH A TEMPORARY REPAIR UNTIL A TYPE-B SLEEVE WAS INSTALLED. THE NEXT DOWNSTREAM GIRTH WELD WAS ALSO REINFORCED WITH A TYPE-B SLEEVE TO MITIGATE CONCERN OF MOVEMENT CAUSED BY THE 2020 CONSTRUCTION. UPDATES TO THIS REPORT: 01/13/2023 - TIME ZONE CORRECTED TO EASTERN TIME. 01/31/2023 - CORRECTED THE DATE THE LEAK WAS EXAMINED. 05/23/2023 - SUBMITTED AS FINAL
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.