Incident details
Operator, cause, commodity and consequences with raw source fields.
GTG incident on 2023-09-01 — NC
Operator
Piedmont Natural Gas Co Inc
Cause
Corrosion Failure
Commodity
Natural Gas
Program
GTG
Damage and Injuries
0 fatalities
0 injuries
Property damage (nominal)
$2,800,000
Incident datetime
2023-09-01 00:00 UTC
Report number
Location
NC
Narrative
A gas odor was reported by the public near service line 281. During the field leak investigation, a leak was discovered on a 4" steel pipe indicating the presence of corrosion. Cathodic protection readings were also performed for several hundred feet in the area which showed positive voltage readings on the pipe as well as evidence of a damaged underground telephone cable. The leak location required daily lane closure for work activities related to the repair. To isolate the leak, two stopples were installed to continue serving customers natural gas. A total of 350 feet of new pipeline was installed to remove the corrosion. After pipe replacement, a hydrostatic test was performed to ensure pipeline integrity. During analysis, the stray current source confirmed to be a telephone cable. Unable to determine a gas volume due to the pinhole size of the leak.
Detailed record list
Report Received Date
2023-09-01 00:00:00
Iyear
2023
Report Number
20230083
Supplemental Number
38851
Report Type
Supplemental Final
Operator Id
15518
Name
Piedmont Natural Gas Co Inc
Operator Street Address
525 South Tryon Street
Operator City Name
Charlotte
Operator State Abbreviation
NC
Operator Postal Code
28202
Time Zone
Eastern
Daylight Savings Ind
Yes
Location Latitude
36.15328
Location Longitude
-81.864213
Nrc Rpt Num
1375586
Additional Nrc Report Numbers
1375705
Commodity Released Type
Natural Gas
Unintentional Release
0.01
Intentional Release
0
Accompanying Liquid
0
Fatality Ind
No
Fatal
0
Injury Ind
No
Injure
0
Status When Identified
Normal Operation, Includes Pauses During Maintenance
Shutdown Due Accident Ind
No
Shutdown Explain
Pipeline Was Isolated. A Cng Trailer Was Used.
Communication State Fed Ind
No
Ignite Ind
No
Upstream Action Taken
Operational Control
Upstream Oprtnl Cntrl Detail
Stopples Will Be Installed.
Downstream Action Taken
Operational Control
Downstream Oprtnl Cntrl Detail
Stopples Will Be Installed.
Num Pub Evacuated
0
On Off Shore
Onshore
Onshore State Abbreviation
Nc
Onshore Postal Code
28604
Onshore City Name
Banner Elk
Onshore County Name
Avery
Designated Location
Not Applicable
Pipe Fac Name
Line 281
Segment Name
Line 281
Federal
No
Location Type
Pipeline Right-Of-Way
Incident Area Type
Underground
Incident Area Subtype
Under Soil
Depth Of Cover
42
Other Underground Facilities
Yes
Crossing
No
Pipe Facility Type
Intrastate
System Part Involved
Onshore Pipeline, Including Valve Sites
Item Involved
Pipe
Pipe Type
Pipe Body
Pipe Diameter
4
Puddle Weld Ind
No
Pipe Wall Thickness
0.237
Pipe Smys
42000
Pipe Specification
Api-5l X-42
Pipe Seam Type
Longitudinal Erw - High Frequency
Pipe Manufacturer
Unknown
Pipe Coating Type
Epoxy
Coating Applied Ind
No
Installation Year
2000
Manufactured Year
Unknown
Material Involved
Carbon Steel
Release Type
Leak
Leak Type
Pinhole
Class Location Type
Class 3 Location
Could Be Hca
No
Pir Radius
76
Heat Damage Ind
No
Non Heat Damage Ind
No
Did Occur In Mca Ind
No
Est Cost Oper Paid
0
Est Cost Unintentional Release
0
Est Cost Intentional Release
0
Est Cost Prop Damage
2800000
Est Cost Emergency
122425
Est Cost Other
0
Gas Cost In Mcf
0
Prpty
2922425
Num Persons Hosp Not Ovnght
0
Num Injured Treated By Emt
0
Num Resident Building Affctd
0
Num Business Building Affctd
0
Wildlife Impact Ind
No
Accident Psig
398
Gas Flow In Pipe In Mcf
1.7
Mop Psig
600
Mop Cfr Section
192.619(A)(1)
Maop Established Date
2000-11-17 00:00:00
Maop Reversal Flow Ind
No
Accident Pressure
Pressure Did Not Exceed Maop
Pressure Restriction Ind
No
Gas Required Odorized Ind
Yes
Gas Odorized Ind
Yes
Length Segment Isolated
3600
Internal Inspection Ind
No
Tight Mitered Ind
Yes
Other Restrictions Ind
Yes
Other Inspection Ind
Yes
Internal Inspection Details
Small Diameter, 4" Diameter Line
Operation Complications Ind
Yes
Low Op Pressure Ind
Yes
Low Flow Ind
Yes
Other Complications Ind
Yes
Inspect Comp Details
Small Diameter, 4" Diameter Line
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
The incident was detected by field leak investigation and pressure remained constant during the incident on the affected piping.
Employee Drug Test Ind
No
Contractor Drug Test Ind
No
Cause
Corrosion Failure
Cause Details
External Corrosion
Internal External
External Corrosion
Visual Exam Results
Localized Pitting
Stray Current Corrosion Ind
Yes
Stray Current Type
Direct Current
Stray Current Details
Telephone Cable
Metallurgical Basis Ind
Yes
Underground Location
Yes
Under Cathodic Protection Ind
Yes
Cathodic Pro Start Year
2000
Shielding Evident
No
Cathodic Survey Type
Yes
Cp Annual Survey Ind
Yes
Close Interval Survey Ind
Yes
Cp Annual Survey Year
2022
Close Interval Survey Year
2021
Prior Damage
Yes
Collected Data Ind
No
Has Hydrtst Conduc Before Ind
No
Direct Asmnt Conducted
Yes, But The Point Of The Accident Was Not Identified As A Dig Site
Direct Asmnt Pnt Not Idntf Yr
2016
Asmnt Ecda Rcnt Year
2016
Asmnt Ecda Rcnt Ind
Yes
Non Destructive Exam Ind
No
Preparer Name
C********** R******
Preparer Title
Gas Regulatory Compliance Analyst
Preparer Email
C******************@d**********.com
Preparer Telephone
704-731-4680
Authorizer Name
F***** B****
Authorizer Title
Manager-Pipeline Safety Governance
Authorizer Telephone
704-731-4618
Authorizer Email
F***********@d**********.com
Narrative
A gas odor was reported by the public near service line 281. During the field leak investigation, a leak was discovered on a 4" steel pipe indicating the presence of corrosion. Cathodic protection readings were also performed for several hundred feet in the area which showed positive voltage readings on the pipe as well as evidence of a damaged underground telephone cable. The leak location required daily lane closure for work activities related to the repair. To isolate the leak, two stopples were installed to continue serving customers natural gas. A total of 350 feet of new pipeline was installed to remove the corrosion. After pipe replacement, a hydrostatic test was performed to ensure pipeline integrity. During analysis, the stray current source confirmed to be a telephone cable. Unable to determine a gas volume due to the pinhole size of the leak.
| Report Received Date | 2023-09-01 00:00:00 |
|---|---|
| Iyear | 2023 |
| Report Number | 20230083 |
| Supplemental Number | 38851 |
| Report Type | Supplemental Final |
| Operator Id | 15518 PHMSA Enforcement |
| Name | Piedmont Natural Gas Co Inc |
| Operator Street Address | 525 South Tryon Street |
| Operator City Name | Charlotte |
| Operator State Abbreviation | NC |
| Operator Postal Code | 28202 |
| Time Zone | Eastern |
| Daylight Savings Ind | Yes |
| Location Latitude | 36.15328 Google Maps OpenStreetMap |
| Location Longitude | -81.864213 Google Maps OpenStreetMap |
| Nrc Rpt Num | 1375586 NRC Report How to search |
| Additional Nrc Report Numbers | 1375705 |
| Commodity Released Type | Natural Gas |
| Unintentional Release | 0.01 |
| Intentional Release | 0 |
| Accompanying Liquid | 0 |
| Fatality Ind | No |
| Fatal | 0 |
| Injury Ind | No |
| Injure | 0 |
| Status When Identified | Normal Operation, Includes Pauses During Maintenance |
| Shutdown Due Accident Ind | No |
| Shutdown Explain | Pipeline Was Isolated. A Cng Trailer Was Used. |
| Communication State Fed Ind | No |
| Ignite Ind | No |
| Upstream Action Taken | Operational Control |
| Upstream Oprtnl Cntrl Detail | Stopples Will Be Installed. |
| Downstream Action Taken | Operational Control |
| Downstream Oprtnl Cntrl Detail | Stopples Will Be Installed. |
| Num Pub Evacuated | 0 |
| On Off Shore | Onshore |
| Onshore State Abbreviation | Nc |
| Onshore Postal Code | 28604 |
| Onshore City Name | Banner Elk |
| Onshore County Name | Avery |
| Designated Location | Not Applicable |
| Pipe Fac Name | Line 281 |
| Segment Name | Line 281 |
| Federal | No |
| Location Type | Pipeline Right-Of-Way |
| Incident Area Type | Underground |
| Incident Area Subtype | Under Soil |
| Depth Of Cover | 42 |
| Other Underground Facilities | Yes |
| Crossing | No |
| Pipe Facility Type | Intrastate |
| System Part Involved | Onshore Pipeline, Including Valve Sites |
| Item Involved | Pipe |
| Pipe Type | Pipe Body |
| Pipe Diameter | 4 |
| Puddle Weld Ind | No |
| Pipe Wall Thickness | 0.237 |
| Pipe Smys | 42000 |
| Pipe Specification | Api-5l X-42 |
| Pipe Seam Type | Longitudinal Erw - High Frequency |
| Pipe Manufacturer | Unknown |
| Pipe Coating Type | Epoxy |
| Coating Applied Ind | No |
| Installation Year | 2000 |
| Manufactured Year | Unknown |
| Material Involved | Carbon Steel |
| Release Type | Leak |
| Leak Type | Pinhole |
| Class Location Type | Class 3 Location |
| Could Be Hca | No |
| Pir Radius | 76 |
| Heat Damage Ind | No |
| Non Heat Damage Ind | No |
| Did Occur In Mca Ind | No |
| Est Cost Oper Paid | 0 |
| Est Cost Unintentional Release | 0 |
| Est Cost Intentional Release | 0 |
| Est Cost Prop Damage | 2800000 |
| Est Cost Emergency | 122425 |
| Est Cost Other | 0 |
| Gas Cost In Mcf | 0 |
| Prpty | 2922425 |
| Num Persons Hosp Not Ovnght | 0 |
| Num Injured Treated By Emt | 0 |
| Num Resident Building Affctd | 0 |
| Num Business Building Affctd | 0 |
| Wildlife Impact Ind | No |
| Accident Psig | 398 |
| Gas Flow In Pipe In Mcf | 1.7 |
| Mop Psig | 600 |
| Mop Cfr Section | 192.619(A)(1) View CFR 49 §192 |
| Maop Established Date | 2000-11-17 00:00:00 |
| Maop Reversal Flow Ind | No |
| Accident Pressure | Pressure Did Not Exceed Maop |
| Pressure Restriction Ind | No |
| Gas Required Odorized Ind | Yes |
| Gas Odorized Ind | Yes |
| Length Segment Isolated | 3600 |
| Internal Inspection Ind | No |
| Tight Mitered Ind | Yes |
| Other Restrictions Ind | Yes |
| Other Inspection Ind | Yes |
| Internal Inspection Details | Small Diameter, 4" Diameter Line |
| Operation Complications Ind | Yes |
| Low Op Pressure Ind | Yes |
| Low Flow Ind | Yes |
| Other Complications Ind | Yes |
| Inspect Comp Details | Small Diameter, 4" Diameter Line |
| 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 | The incident was detected by field leak investigation and pressure remained constant during the incident on the affected piping. |
| Employee Drug Test Ind | No |
| Contractor Drug Test Ind | No |
| Cause | Corrosion Failure |
| Cause Details | External Corrosion |
| Internal External | External Corrosion |
| Visual Exam Results | Localized Pitting |
| Stray Current Corrosion Ind | Yes |
| Stray Current Type | Direct Current |
| Stray Current Details | Telephone Cable |
| Metallurgical Basis Ind | Yes |
| Underground Location | Yes |
| Under Cathodic Protection Ind | Yes |
| Cathodic Pro Start Year | 2000 |
| Shielding Evident | No |
| Cathodic Survey Type | Yes |
| Cp Annual Survey Ind | Yes |
| Close Interval Survey Ind | Yes |
| Cp Annual Survey Year | 2022 |
| Close Interval Survey Year | 2021 |
| Prior Damage | Yes |
| Collected Data Ind | No |
| Has Hydrtst Conduc Before Ind | No |
| Direct Asmnt Conducted | Yes, But The Point Of The Accident Was Not Identified As A Dig Site |
| Direct Asmnt Pnt Not Idntf Yr | 2016 |
| Asmnt Ecda Rcnt Year | 2016 |
| Asmnt Ecda Rcnt Ind | Yes |
| Non Destructive Exam Ind | No |
| Preparer Name | C********** R****** |
| Preparer Title | Gas Regulatory Compliance Analyst |
| Preparer Email | C******************@d**********.com |
| Preparer Telephone | 704-731-4680 |
| Authorizer Name | F***** B**** |
| Authorizer Title | Manager-Pipeline Safety Governance |
| Authorizer Telephone | 704-731-4618 |
| Authorizer Email | F***********@d**********.com |
| Narrative | A gas odor was reported by the public near service line 281. During the field leak investigation, a leak was discovered on a 4" steel pipe indicating the presence of corrosion. Cathodic protection readings were also performed for several hundred feet in the area which showed positive voltage readings on the pipe as well as evidence of a damaged underground telephone cable. The leak location required daily lane closure for work activities related to the repair. To isolate the leak, two stopples were installed to continue serving customers natural gas. A total of 350 feet of new pipeline was installed to remove the corrosion. After pipe replacement, a hydrostatic test was performed to ensure pipeline integrity. During analysis, the stray current source confirmed to be a telephone cable. Unable to determine a gas volume due to the pinhole size of the leak. |
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