NORTHERN NATURAL GAS CO
gas_transmission Incident — — July 10, 2023
Incident Information
| Incident Date | July 10, 2023 |
| Operator | NORTHERN NATURAL GAS CO |
| Commodity | NATURAL GAS |
| Pipeline Type | gas_transmission |
Location
| State | |
| Coordinates | 45.42593, -91.76063 |
Cause
| Cause | INCORRECT OPERATION |
| Subcause | DAMAGE BY OPERATOR OR OPERATOR'S CONTRACTOR NOT RELATED TO EXCAVATION AND NOT DUE TO MOTORIZED VEHICLE/EQUIPMENT DAMAGE |
Casualties
| Fatalities | 0 |
| Injuries | 0 |
Costs
| Property Damage | $1,000 |
| Emergency Response | $245,000 |
| Other Costs | $40,000 |
Location Map
Incident Narrative
"ON JULY 10, 2023, A WELDER WAS WELDING A LINE-STOP FITTING ON NORTHERN NATURAL GAS COMPANY'S WIB14801 LADYSMITH BRANCH LINE AT MILEPOST 1.15 TO ACCOMMODATE A NEW PIPELINE SEGMENT TIE-IN. AT 1100 HOURS, THE WELDER BEGAN WELDING THE ""BUTTER TEMPER BEAD PASS"" REQUIRED PRIOR TO WELDING THE LINE-STOP FITTING TO THE PIPELINE. SEVEN MINUTES LATER, THE WELDER BURNED THROUGH THE PIPELINE, CREATING A 1/16-INCH HOLE. WHEN THE LEAK STARTED, ALL PARTIES EXITED THE BELL HOLE AND STOPPED ALL IGNITION SOURCES. THE BEST LOCATION FOR THE LINE STOP FITTING WAS FOUND TO BE 0.150"" WALL THICKNESS. THIS IS WHERE THE BURN THROUGH OCCURRED. THE INCIDENT'S ROOT CAUSE WAS THE WELDER DID NOT FOLLOW THE PROCEDURE FOR WELDING ON THIN-WALL PIPE WHILE IN-SERVICE. THE WELDER WAS OUT OF POSITION AND DID NOT HAVE THE MINIMUM EXPERIENCE NORTHERN REQUIRES TO COMPLETE THIS CHALLENGING WELDING PROCESS. ON JULY 16, 2023, AT 14:50 THE PROJECT WAS COMPLETED, AND THE LADYSMITH BRANCH LINE WAS RETURNED TO NORMAL SERVICE."
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.