Incident details
Operator, cause, commodity and consequences with raw source fields.
GTG incident on 2011-11-10 — TX
Operator
Transwestern Pipeline Company Llc
Cause
Corrosion Failure
Commodity
Natural Gas
Program
GTG
Damage and Injuries
0 fatalities
0 injuries
Property damage (nominal)
$15,800
Incident datetime
2011-11-10 15:43
Report number
Location
TX
Narrative
On november 10, 2011 verification digs were conducted on transwestern's (line number azmm121) 30' pipeline as a result of an ili run that was performed may 12, 2011. The pipeline pressure was lowered to 80% of the operating pressure per transwestern's sop I.11 and a 40' joint of pipe was exposed in the location shown on the ili dig sheet. The coating was removed from the pipe and corrosion was found in the location as identified on the ili report. The surface of the pipe was sandblasted to remove the remaining coating and the corrosion technician began inspecting the corroded area to verify the accuracy of the ili report. The deepest pit found in an area of general corrosion (7.6' long x 10.5' wide) measured 48% deep with a length and width of 0.625'. After all the corrosion measurements were completed wet magnetic particle inspection was conducted to look for any signs of scc cracks, there were no visible signs of scc. Once the wet magnetic particle testing was completed the pipe surface was re-blasted to remove the wet magnetic particle medium and white contrast paint off the pipe. Once the sandblasting was completed the corrosion technician went back down into the ditch to inspect the surface of the pipe for coating repair. While in the ditch the technician heard a leak and immediately notified gas control and operations management of a leak (15.43). The pipeline was immediately isolated (approximately 16.2 miles of pipeline) from mainline valves 2010 and 2011. At 16.32 operations began blowing down the pipeline. Blow down was completed at 21.07 with less than 5psi line pressure in the pipeline. The bell hole was checked for gas with a gas detector and no gas was detected in the ditch. A full encirclement pressure containing sleeve was installed over the pinhole leak and the pipeline was returned to service on november 12 at 18.23 ge pii (manufacture and operator of the ili tool) did a detailed analysis of the reported 48% wall loss pit that leaked and concluded that the dimensions of the pit were beyond the capabilities of the magnetic tool to properly size the pinhole leak. **this report is being submitted in response to PHMSA's request, (docket id PHMSA-2013-0028), for supplemental reports from operators who submitted reports for incidents occurring after january 1, 2010, with any of the following: (1) ``pipe girth weld'' was selected as the ``item involved in incident'' in part c3 of the report. The revised report collects data about the pipe adjacent to the girth weld. (2) ``function of pipeline system'' is null in part e5f of the report. The revised report collects the function of the pipeline system for all incidents.** this supplemental report is to acknowledge that the two relevant sections in PHMSA's request have been reviewed and no further actions were needed.
Detailed record list
Report Received Date
2011-12-08 00:00:00
Iyear
2011
Report Number
20110391
Supplemental Number
16028
Report Type
Supplemental Final
Operator Id
19610
Name
Transwestern Pipeline Company Llc
Operator Street Address
1300 Main Street
Operator City Name
Houston
Operator State Abbreviation
TX
Operator Postal Code
77002
Local Datetime
2011-11-10 15:43:00
Location Latitude
35.280217
Location Longitude
-112.737573
Nrc Rpt Num
995198
Nrc Rpt Datetime
2011-11-10 16:56:00
Commodity Released Type
Natural Gas
Unintentional Release
1
Intentional Release
80700
Accompanying Liquid
0
Fatality Ind
No
Fatal
0
Injury Ind
No
Injure
0
Shutdown Due Accident Ind
Yes
Shutdown Datetime
2011-11-10 16:32:00
Restart Datetime
2011-11-12 18:23:00
Ignite Ind
No
Explode Ind
No
Num Pub Evacuated
0
Incident Identified Datetime
2011-11-10 15:43:00
On Site Datetime
2011-11-10 15:43:00
On Off Shore
Onshore
Onshore State Abbreviation
Az
Onshore Postal Code
86337
Onshore City Name
Seligman
Onshore County Name
Yavapai
Designated Location
Milepost
Designated Name
Mp 52.31
Pipe Fac Name
Tw 30 Inch Mainline Between Station 1 And Station2
Segment Name
Azmm121
Federal
No
Location Type
Pipeline Right-Of-Way
Incident Area Type
Underground
Incident Area Subtype
Exposed Due To Excavation
Depth Of Cover
40
Crossing
No
Pipe Facility Type
Interstate
System Part Involved
Onshore Pipeline, Including Valve Sites
Item Involved
Pipe
Pipe Type
Pipe Body
Pipe Diameter
30
Pipe Wall Thickness
0.375
Pipe Smys
60000
Pipe Specification
Api 5lx
Pipe Seam Type
Dsaw
Pipe Manufacturer
Kaiser Steel
Pipe Coating Type
Coal Tar
Installation Year
1960
Manufactured Year
1959
Material Involved
Carbon Steel
Release Type
Leak
Leak Type
Pinhole
Class Location Type
Class 1 Location
Could Be Hca
No
Pir Radius
657
Heat Damage Ind
No
Non Heat Damage Ind
No
Hca Fatalities Ind
No
Est Cost Oper Paid
0
Est Cost Unintentional Release
1
Est Cost Intentional Release
305046
Est Cost Prop Damage
15800
Est Cost Emergency
150
Est Cost Other
0
Prpty
320997
Accident Psig
636
Mop Psig
1008
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
85302
Internal Inspection 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
Local Operating Personnel, Including Contractors
Operator Type
Operator Employee
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
A pinhole leak was discovered during excavation to repair an anamoly.
Employee Drug Test Ind
No
Contractor Drug Test Ind
No
Cause
Corrosion Failure
Cause Details
External Corrosion
Internal External
External Corrosion
Visual Exam Results
General Corrosion
Galvanic Corrosion Ind
Yes
Field Exam Basis Ind
Yes
Underground Location
Yes
Under Cathodic Protection Ind
Yes
Cathodic Pro Start Year
1960
Shielding Evident
Yes
Cathodic Survey Type
Yes
Cp Annual Survey Ind
Yes
Cp Annual Survey Year
2011
Prior Damage
Yes
Collected Data Ind
Yes
Axial Magnetic Flx Lkg Ind
Yes
Geometry Deformation Ind
Yes
Axial Recent Year
2011
Geometry Recent Year
2011
Has Hydrtst Conduc Before Ind
No
Direct Asmnt Conducted
No
Non Destructive Exam Ind
No
Preparer Name
N***** H******
Preparer Title
Director Interstate Regulatory Compliance
Preparer Email
N*************@e*************.com
Preparer Telephone
713-857-5479
Authorizer Name
N***** H******
Authorizer Title
Director Interstate Regulatory Compliance
Authorizer Telephone
713-857-5479
Authorizer Email
N*************@e*************.com
Narrative
On november 10, 2011 verification digs were conducted on transwestern's (line number azmm121) 30' pipeline as a result of an ili run that was performed may 12, 2011. The pipeline pressure was lowered to 80% of the operating pressure per transwestern's sop I.11 and a 40' joint of pipe was exposed in the location shown on the ili dig sheet. The coating was removed from the pipe and corrosion was found in the location as identified on the ili report. The surface of the pipe was sandblasted to remove the remaining coating and the corrosion technician began inspecting the corroded area to verify the accuracy of the ili report. The deepest pit found in an area of general corrosion (7.6' long x 10.5' wide) measured 48% deep with a length and width of 0.625'. After all the corrosion measurements were completed wet magnetic particle inspection was conducted to look for any signs of scc cracks, there were no visible signs of scc. Once the wet magnetic particle testing was completed the pipe surface was re-blasted to remove the wet magnetic particle medium and white contrast paint off the pipe. Once the sandblasting was completed the corrosion technician went back down into the ditch to inspect the surface of the pipe for coating repair. While in the ditch the technician heard a leak and immediately notified gas control and operations management of a leak (15.43). The pipeline was immediately isolated (approximately 16.2 miles of pipeline) from mainline valves 2010 and 2011. At 16.32 operations began blowing down the pipeline. Blow down was completed at 21.07 with less than 5psi line pressure in the pipeline. The bell hole was checked for gas with a gas detector and no gas was detected in the ditch. A full encirclement pressure containing sleeve was installed over the pinhole leak and the pipeline was returned to service on november 12 at 18.23 ge pii (manufacture and operator of the ili tool) did a detailed analysis of the reported 48% wall loss pit that leaked and concluded that the dimensions of the pit were beyond the capabilities of the magnetic tool to properly size the pinhole leak. **this report is being submitted in response to PHMSA's request, (docket id PHMSA-2013-0028), for supplemental reports from operators who submitted reports for incidents occurring after january 1, 2010, with any of the following: (1) ``pipe girth weld'' was selected as the ``item involved in incident'' in part c3 of the report. The revised report collects data about the pipe adjacent to the girth weld. (2) ``function of pipeline system'' is null in part e5f of the report. The revised report collects the function of the pipeline system for all incidents.** this supplemental report is to acknowledge that the two relevant sections in PHMSA's request have been reviewed and no further actions were needed.
| Report Received Date | 2011-12-08 00:00:00 |
|---|---|
| Iyear | 2011 |
| Report Number | 20110391 |
| Supplemental Number | 16028 |
| Report Type | Supplemental Final |
| Operator Id | 19610 PHMSA Enforcement |
| Name | Transwestern Pipeline Company Llc |
| Operator Street Address | 1300 Main Street |
| Operator City Name | Houston |
| Operator State Abbreviation | TX |
| Operator Postal Code | 77002 |
| Local Datetime | 2011-11-10 15:43:00 |
| Location Latitude | 35.280217 Google Maps OpenStreetMap |
| Location Longitude | -112.737573 Google Maps OpenStreetMap |
| Nrc Rpt Num | 995198 NRC Report How to search |
| Nrc Rpt Datetime | 2011-11-10 16:56:00 |
| Commodity Released Type | Natural Gas |
| Unintentional Release | 1 |
| Intentional Release | 80700 |
| Accompanying Liquid | 0 |
| Fatality Ind | No |
| Fatal | 0 |
| Injury Ind | No |
| Injure | 0 |
| Shutdown Due Accident Ind | Yes |
| Shutdown Datetime | 2011-11-10 16:32:00 |
| Restart Datetime | 2011-11-12 18:23:00 |
| Ignite Ind | No |
| Explode Ind | No |
| Num Pub Evacuated | 0 |
| Incident Identified Datetime | 2011-11-10 15:43:00 |
| On Site Datetime | 2011-11-10 15:43:00 |
| On Off Shore | Onshore |
| Onshore State Abbreviation | Az |
| Onshore Postal Code | 86337 |
| Onshore City Name | Seligman |
| Onshore County Name | Yavapai |
| Designated Location | Milepost |
| Designated Name | Mp 52.31 |
| Pipe Fac Name | Tw 30 Inch Mainline Between Station 1 And Station2 |
| Segment Name | Azmm121 |
| Federal | No |
| Location Type | Pipeline Right-Of-Way |
| Incident Area Type | Underground |
| Incident Area Subtype | Exposed Due To Excavation |
| Depth Of Cover | 40 |
| Crossing | No |
| Pipe Facility Type | Interstate |
| System Part Involved | Onshore Pipeline, Including Valve Sites |
| Item Involved | Pipe |
| Pipe Type | Pipe Body |
| Pipe Diameter | 30 |
| Pipe Wall Thickness | 0.375 |
| Pipe Smys | 60000 |
| Pipe Specification | Api 5lx |
| Pipe Seam Type | Dsaw |
| Pipe Manufacturer | Kaiser Steel |
| Pipe Coating Type | Coal Tar |
| Installation Year | 1960 |
| Manufactured Year | 1959 |
| Material Involved | Carbon Steel |
| Release Type | Leak |
| Leak Type | Pinhole |
| Class Location Type | Class 1 Location |
| Could Be Hca | No |
| Pir Radius | 657 |
| Heat Damage Ind | No |
| Non Heat Damage Ind | No |
| Hca Fatalities Ind | No |
| Est Cost Oper Paid | 0 |
| Est Cost Unintentional Release | 1 |
| Est Cost Intentional Release | 305046 |
| Est Cost Prop Damage | 15800 |
| Est Cost Emergency | 150 |
| Est Cost Other | 0 |
| Prpty | 320997 |
| Accident Psig | 636 |
| Mop Psig | 1008 |
| 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 | 85302 |
| Internal Inspection 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 | Local Operating Personnel, Including Contractors |
| Operator Type | Operator Employee |
| 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 | A pinhole leak was discovered during excavation to repair an anamoly. |
| Employee Drug Test Ind | No |
| Contractor Drug Test Ind | No |
| Cause | Corrosion Failure |
| Cause Details | External Corrosion |
| Internal External | External Corrosion |
| Visual Exam Results | General Corrosion |
| Galvanic Corrosion Ind | Yes |
| Field Exam Basis Ind | Yes |
| Underground Location | Yes |
| Under Cathodic Protection Ind | Yes |
| Cathodic Pro Start Year | 1960 |
| Shielding Evident | Yes |
| Cathodic Survey Type | Yes |
| Cp Annual Survey Ind | Yes |
| Cp Annual Survey Year | 2011 |
| Prior Damage | Yes |
| Collected Data Ind | Yes |
| Axial Magnetic Flx Lkg Ind | Yes |
| Geometry Deformation Ind | Yes |
| Axial Recent Year | 2011 |
| Geometry Recent Year | 2011 |
| Has Hydrtst Conduc Before Ind | No |
| Direct Asmnt Conducted | No |
| Non Destructive Exam Ind | No |
| Preparer Name | N***** H****** |
| Preparer Title | Director Interstate Regulatory Compliance |
| Preparer Email | N*************@e*************.com |
| Preparer Telephone | 713-857-5479 |
| Authorizer Name | N***** H****** |
| Authorizer Title | Director Interstate Regulatory Compliance |
| Authorizer Telephone | 713-857-5479 |
| Authorizer Email | N*************@e*************.com |
| Narrative | On november 10, 2011 verification digs were conducted on transwestern's (line number azmm121) 30' pipeline as a result of an ili run that was performed may 12, 2011. The pipeline pressure was lowered to 80% of the operating pressure per transwestern's sop I.11 and a 40' joint of pipe was exposed in the location shown on the ili dig sheet. The coating was removed from the pipe and corrosion was found in the location as identified on the ili report. The surface of the pipe was sandblasted to remove the remaining coating and the corrosion technician began inspecting the corroded area to verify the accuracy of the ili report. The deepest pit found in an area of general corrosion (7.6' long x 10.5' wide) measured 48% deep with a length and width of 0.625'. After all the corrosion measurements were completed wet magnetic particle inspection was conducted to look for any signs of scc cracks, there were no visible signs of scc. Once the wet magnetic particle testing was completed the pipe surface was re-blasted to remove the wet magnetic particle medium and white contrast paint off the pipe. Once the sandblasting was completed the corrosion technician went back down into the ditch to inspect the surface of the pipe for coating repair. While in the ditch the technician heard a leak and immediately notified gas control and operations management of a leak (15.43). The pipeline was immediately isolated (approximately 16.2 miles of pipeline) from mainline valves 2010 and 2011. At 16.32 operations began blowing down the pipeline. Blow down was completed at 21.07 with less than 5psi line pressure in the pipeline. The bell hole was checked for gas with a gas detector and no gas was detected in the ditch. A full encirclement pressure containing sleeve was installed over the pinhole leak and the pipeline was returned to service on november 12 at 18.23 ge pii (manufacture and operator of the ili tool) did a detailed analysis of the reported 48% wall loss pit that leaked and concluded that the dimensions of the pit were beyond the capabilities of the magnetic tool to properly size the pinhole leak. **this report is being submitted in response to PHMSA's request, (docket id PHMSA-2013-0028), for supplemental reports from operators who submitted reports for incidents occurring after january 1, 2010, with any of the following: (1) ``pipe girth weld'' was selected as the ``item involved in incident'' in part c3 of the report. The revised report collects data about the pipe adjacent to the girth weld. (2) ``function of pipeline system'' is null in part e5f of the report. The revised report collects the function of the pipeline system for all incidents.** this supplemental report is to acknowledge that the two relevant sections in PHMSA's request have been reviewed and no further actions were needed. |
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