GTG incident on 2013-03-14 — TX

Operator
Gas Transmission Northwest Llc
Cause
Equipment Failure
Commodity
Natural Gas
Program
GTG
Damage and Injuries
0 fatalities 0 injuries
Property damage (nominal)
$313,000
Incident datetime
2013-03-14 17:05
Report number
Location
TX
Narrative
The landowner reported an area of dead vegetation over the pipeline. Pipeline personnel detected gas in a probe hole over the pipeline, but not in the air above ground. The pipeline section was isolated and pressure reduced to 125 psig. The area was excavated and a branch connection was found. The 2" branch connection had a pipe cap and the leak was found at the threads of the pipe cap. The cause of the leakage past the threads of the fitting is unknown, but the fitting was not broken. The pipeline was vented to near atmospheric pressure. The branch connection was sandblasted and threaded connection was seal-welded. The pipeline was put back in operation and the exposed pipe was recoated and backfilled.
Detailed record list
Report Received Date
2013-04-12 00:00:00
Iyear
2013
Report Number
20130032
Supplemental Number
15980
Report Type
Supplemental Final
Operator Id
Name
Gas Transmission Northwest Llc
Operator Street Address
700 Louisiana Street Suite 700
Operator City Name
Houston
Operator State Abbreviation
TX
Operator Postal Code
77002
Local Datetime
2013-03-14 17:05:00
Location Latitude
Location Longitude
Nrc Rpt Num
Nrc Rpt Datetime
2013-03-14 17:44:00
Commodity Released Type
Natural Gas
Unintentional Release
1
Intentional Release
52616
Accompanying Liquid
0
Fatality Ind
No
Fatal
0
Injury Ind
No
Injure
0
Shutdown Due Accident Ind
Yes
Shutdown Datetime
2013-03-14 21:15:00
Restart Datetime
2013-03-21 14:20:00
Ignite Ind
No
Explode Ind
No
Num Pub Evacuated
0
Incident Identified Datetime
2013-03-14 17:05:00
On Site Datetime
2013-03-14 17:05:00
On Off Shore
Onshore
Onshore State Abbreviation
Wa
Onshore Postal Code
99143
Onshore City Name
Lacrosse
Onshore County Name
Whitman
Designated Location
Milepost
Designated Name
179.3
Pipe Fac Name
B-Line
Segment Name
Mlv 6-2
Federal
No
Location Type
Pipeline Right-Of-Way
Incident Area Type
Underground
Incident Area Subtype
Under Soil
Depth Of Cover
72
Crossing
No
Pipe Facility Type
Interstate
System Part Involved
Onshore Pipeline, Including Valve Sites
Item Involved
Drain Lines
Installation Year
1992
Material Involved
Carbon Steel
Release Type
Leak
Leak Type
Seal Or Packing
Class Location Type
Class 1 Location
Could Be Hca
No
Pir Radius
935
Heat Damage Ind
No
Non Heat Damage Ind
No
Hca Fatalities Ind
No
Est Cost Oper Paid
25000
Est Cost Unintentional Release
4
Est Cost Intentional Release
204007
Est Cost Prop Damage
313000
Est Cost Emergency
2019
Est Cost Other
0
Prpty
544030
Accident Psig
860
Mop Psig
911
Mop Cfr Section
Not On Omb-Approved Form When Submitted
Accident Pressure
Pressure Did Not Exceed Maop
Pressure Restriction Ind
No
Upstream Valve Type Ind
Manual
Downstream Valve Type Ind
Manual
Length Segment Isolated
99175
Internal Inspection Ind
No
Diameter Change Ind
Yes
Operation Complications Ind
No
Pipeline Function
Transmission System
Scada In Place Ind
Yes
Scada Operating Ind
Yes
Scada Functional Ind
Yes
Scada Detection Ind
No
Scada Conf Ind
No
Accident Identifier
Notification From Public
Investigation Status
No, the operator did not find that an investigation of the controller(s) actions or control room issues was necessary due to: (provide an explanation for why the operator did not investigate)
Investigation Status Details
Leak was a threaded fitting not affected by control room activity.
Employee Drug Test Ind
No
Contractor Drug Test Ind
No
Cause
Equipment Failure
Cause Details
Threaded Connection/coupling Failure
Eq Failure Type
Threaded Connection/coupling Failure
Other Stripped Ind
Threaded Fitting
Eq Additional Other Ind
Yes
Eq Additional Other Details
Cause Of Leak Past Threads Is Unknown, But The Fitting Did Not Break.
Preparer Name
K*** S****
Preparer Title
Compliance Specialist
Preparer Email
K*********@t**********.com
Preparer Telephone
(509) 546-8865
Preparer Fax
(509) 546-8825
Authorizer Name
K*** S****
Authorizer Title
Compliance Specialist
Authorizer Telephone
(509) 546-8865
Authorizer Email
K*********@t**********.com
Narrative
The landowner reported an area of dead vegetation over the pipeline. Pipeline personnel detected gas in a probe hole over the pipeline, but not in the air above ground. The pipeline section was isolated and pressure reduced to 125 psig. The area was excavated and a branch connection was found. The 2" branch connection had a pipe cap and the leak was found at the threads of the pipe cap. The cause of the leakage past the threads of the fitting is unknown, but the fitting was not broken. The pipeline was vented to near atmospheric pressure. The branch connection was sandblasted and threaded connection was seal-welded. The pipeline was put back in operation and the exposed pipe was recoated and backfilled.
Report Received Date 2013-04-12 00:00:00
Iyear 2013
Report Number 20130032
Supplemental Number 15980
Report Type Supplemental Final
Operator Id 15014 PHMSA Enforcement
Name Gas Transmission Northwest Llc
Operator Street Address 700 Louisiana Street Suite 700
Operator City Name Houston
Operator State Abbreviation TX
Operator Postal Code 77002
Local Datetime 2013-03-14 17:05:00
Location Latitude 46.855857 Google Maps OpenStreetMap
Location Longitude -117.809636 Google Maps OpenStreetMap
Nrc Rpt Num 1041089 NRC Report How to search
Nrc Rpt Datetime 2013-03-14 17:44:00
Commodity Released Type Natural Gas
Unintentional Release 1
Intentional Release 52616
Accompanying Liquid 0
Fatality Ind No
Fatal 0
Injury Ind No
Injure 0
Shutdown Due Accident Ind Yes
Shutdown Datetime 2013-03-14 21:15:00
Restart Datetime 2013-03-21 14:20:00
Ignite Ind No
Explode Ind No
Num Pub Evacuated 0
Incident Identified Datetime 2013-03-14 17:05:00
On Site Datetime 2013-03-14 17:05:00
On Off Shore Onshore
Onshore State Abbreviation Wa
Onshore Postal Code 99143
Onshore City Name Lacrosse
Onshore County Name Whitman
Designated Location Milepost
Designated Name 179.3
Pipe Fac Name B-Line
Segment Name Mlv 6-2
Federal No
Location Type Pipeline Right-Of-Way
Incident Area Type Underground
Incident Area Subtype Under Soil
Depth Of Cover 72
Crossing No
Pipe Facility Type Interstate
System Part Involved Onshore Pipeline, Including Valve Sites
Item Involved Drain Lines
Installation Year 1992
Material Involved Carbon Steel
Release Type Leak
Leak Type Seal Or Packing
Class Location Type Class 1 Location
Could Be Hca No
Pir Radius 935
Heat Damage Ind No
Non Heat Damage Ind No
Hca Fatalities Ind No
Est Cost Oper Paid 25000
Est Cost Unintentional Release 4
Est Cost Intentional Release 204007
Est Cost Prop Damage 313000
Est Cost Emergency 2019
Est Cost Other 0
Prpty 544030
Accident Psig 860
Mop Psig 911
Mop Cfr Section Not On Omb-Approved Form When Submitted View CFR 49 §192
Accident Pressure Pressure Did Not Exceed Maop
Pressure Restriction Ind No
Upstream Valve Type Ind Manual
Downstream Valve Type Ind Manual
Length Segment Isolated 99175
Internal Inspection Ind No
Diameter Change Ind Yes
Operation Complications Ind No
Pipeline Function Transmission System
Scada In Place Ind Yes
Scada Operating Ind Yes
Scada Functional Ind Yes
Scada Detection Ind No
Scada Conf Ind No
Accident Identifier Notification From Public
Investigation Status No, the operator did not find that an investigation of the controller(s) actions or control room issues was necessary due to: (provide an explanation for why the operator did not investigate)
Investigation Status Details Leak was a threaded fitting not affected by control room activity.
Employee Drug Test Ind No
Contractor Drug Test Ind No
Cause Equipment Failure
Cause Details Threaded Connection/coupling Failure
Eq Failure Type Threaded Connection/coupling Failure
Other Stripped Ind Threaded Fitting
Eq Additional Other Ind Yes
Eq Additional Other Details Cause Of Leak Past Threads Is Unknown, But The Fitting Did Not Break.
Preparer Name K*** S****
Preparer Title Compliance Specialist
Preparer Email K*********@t**********.com
Preparer Telephone (509) 546-8865
Preparer Fax (509) 546-8825
Authorizer Name K*** S****
Authorizer Title Compliance Specialist
Authorizer Telephone (509) 546-8865
Authorizer Email K*********@t**********.com
Narrative The landowner reported an area of dead vegetation over the pipeline. Pipeline personnel detected gas in a probe hole over the pipeline, but not in the air above ground. The pipeline section was isolated and pressure reduced to 125 psig. The area was excavated and a branch connection was found. The 2" branch connection had a pipe cap and the leak was found at the threads of the pipe cap. The cause of the leakage past the threads of the fitting is unknown, but the fitting was not broken. The pipeline was vented to near atmospheric pressure. The branch connection was sandblasted and threaded connection was seal-welded. The pipeline was put back in operation and the exposed pipe was recoated and backfilled.

All rights reserved. Copyright © by ClearPHMSA