Incident details
Operator, cause, commodity and consequences with raw source fields.
HL incident on 2025-08-26 — TX
Operator
Nustar Pipeline Operating Partnership L.p.
Cause
Equipment Failure
Commodity
Hvl Or Other Flammable Or Toxic Fluid Which Is A Gas At Ambient Conditions
Program
HL
Damage and Injuries
0 fatalities
0 injuries
Property damage (nominal)
$22,600
Incident datetime
2025-08-26 11:48
Report number
Location
TX
Narrative
A hunter came upon an area of dead vegetation and an ammonia odor and called the control center around 9:20am on 8/26. The pipeline was shutdown out of precaution and local personnel were dispatched and arrived onsite and confirmed a release at 11:48am. All agency notifications were made. The maintenance crew was dispatched and began excavating on 8/28 and found a split seam on a stopple tee that caused the release. The leak was stopped at 12:50pm on the 28th. A calculated amount of 1.48bbls (324lbs) was released. **update** the size of the leak was measured as 1/64-inch diameter hole in the side seam weld. This was not sent for metallurgical analysis as it appeared to have the same characteristics as a previous stopple side seam failure depicting weld defects with lack of fusion and lack of penetration of the weld. To further investigate this threat, we have initiated a program to excavate and inspect high priority stopples on our mainline. This effort started in november of 2025 and is currently ongoing. In addition, we have identified similar style stopple tees and plan to remove upwards of 56 stopples over the course of 2026.
Detailed record list
Report Received Date
2025-09-24 00:00:00
Iyear
2025
Report Number
20250230
Supplemental Number
41579
Report Type
Supplemental Final
Operator Id
10012
Name
Nustar Pipeline Operating Partnership L.p.
Operator Street Address
8111 Westchester Drive
Operator City Name
Dallas
Operator State Abbreviation
TX
Operator Postal Code
75225
Local Datetime
2025-08-26 09:20:00
Time Zone
Central
Daylight Savings Ind
Yes
Location Latitude
30.49683
Location Longitude
-91.62127
Commodity Released Type
Hvl Or Other Flammable Or Toxic Fluid Which Is A Gas At Ambient Conditions
Commodity Subtype
Anhydrous Ammonia
Unintentional Release Bbls
1.48
Intentional Release Bbls
0
Recovered Bbls
0
Fatality Ind
No
Fatal
0
Injury Ind
No
Injure
0
Accident Identifier
Notification From Public
Incident Identified Datetime
2025-08-26 11:48:00
System Part Involved
Onshore Pipeline, Including Valve Sites
On Off Shore
Onshore
Status When Identified
Normal Operation, Includes Pauses Between Batches And During Maintenance
Shutdown Due Accident Ind
Yes
Shutdown Datetime
2025-08-26 09:36:00
Restart Datetime
2025-08-28 18:00:00
Communication State Fed Ind
No
On Site Datetime
2025-08-26 11:48:00
Confirmed Discovery Datetime
2025-08-26 11:48:00
Nrc Rpt Datetime
2025-08-26 12:29:00
Nrc Rpt Num
1440940
Additional Nrc Report Numbers
1441114
Ignite Ind
No
Upstream Action Taken
Valve Closure
Upstream Valve Close Datetime
2025-08-26 09:36:00
Upstream Valve Type Ind
Remotely Controlled
Downstream Action Taken
Valve Closure
Downstream Vlv Close Datetime
2025-08-26 09:36:00
Downstream Valve Type Ind
Remotely Controlled
Num Pub Evacuated
0
Pipe Fac Name
Donaldsonville Jct. To Marksville Station
Segment Name
Ramah Station 8-Inch To Palmetto Station
Onshore State Abbreviation
La
Onshore Postal Code
70750
Onshore City Name
Not Within A Municipality
Onshore County Name
Iberville
Designated Location
Survey Station No.
Designated Name
3041+22
Federal
Yes
Location Type
Pipeline Right-Of-Way
Incident Area Type
Underground
Incident Area Subtype
Under Soil
Depth Of Cover
54
Crossing
No
Pipe Facility Type
Interstate
Item Involved
Tap Fitting(Stopple, Thread-O-Ring, Weld-O-Let, Etc.)
Installation Year
1997
Manufactured Year
Unknown
Material Involved
Carbon Steel
Release Type
Leak
Leak Type
Other
Leak Type Other
Side Seam Failed - Stopple Tee
Wildlife Impact Ind
No
Soil Contamination
Yes
Long Term Assessment
No
Remediation Ind
No
Water Contam Ind
No
Could Be Hca
Yes
Commodity Reached Hca
No
Est Cost Oper Paid
0
Est Cost Gas Released
100
Est Cost Prop Damage
22600
Est Cost Emergency
0
Est Cost Environmental
0
Est Cost Other
0
Prpty
22700
Num Persons Hosp Not Ovnght
0
Num Injured Treated By Emt
0
Num Resident Building Affctd
0
Num Business Building Affctd
0
Accident Psig
717
Mop Psig
1340
Mop Cfr Section
Subpart E Pressure Test �195.406(A)(3)
Maop Established Date
1969-03-15 00:00:00
Maop Reversal Flow Ind
No
Accident Pressure
Pressure Did Not Exceed Mop
Pressure Restriction Ind
No
Length Segment Isolated
10479
Internal Inspection Ind
Yes
Operation Complications Ind
Yes
Incompat Commod Ind
Yes
Pipeline Function
> 20% Smys Regulated Transmission
Scada In Place Ind
Yes
Scada Operating Ind
Yes
Scada Functional Ind
Yes
Scada Detection Ind
No
Scada Conf Ind
No
Cpm In Place Ind
Yes
Cpm Operating Ind
Yes
Cpm Functional Ind
Yes
Cpm Detection Ind
No
Cpm Conf Ind
No
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 leak coming from the stopple tee was small enough it rendered the leak un-detectable by the control room (scada/crm)
Employee Drug Test Ind
No
Contractor Drug Test Ind
No
Cause
Equipment Failure
Cause Details
Malfunction Of Control/relief Equipment
Eq Failure Type
Malfunction Of Control/relief Equipment
Stopple Control Fitting Ind
Yes
Eq Additional Other Ind
Yes
Eq Additional Other Details
Side Seam Weld On Stopple Tee.
Preparer Name
D** T******
Preparer Title
Sr Manager - Health And Safety
Preparer Email
D**********@s*****.com
Preparer Telephone
3167217056
Prepared Date
2025-11-13 00:00:00
Local Contact Name
D** T******
Local Contact Email
D**********@s*****.com
Local Contact Telephone
3167217056
Authorizer Name
D** T******
Authorizer Telephone
3167217056
Authorizer Title
Sr Manager - Health And Safety
Authorizer Email
D**********@s*****.com
Narrative
A hunter came upon an area of dead vegetation and an ammonia odor and called the control center around 9:20am on 8/26. The pipeline was shutdown out of precaution and local personnel were dispatched and arrived onsite and confirmed a release at 11:48am. All agency notifications were made. The maintenance crew was dispatched and began excavating on 8/28 and found a split seam on a stopple tee that caused the release. The leak was stopped at 12:50pm on the 28th. A calculated amount of 1.48bbls (324lbs) was released. **update** the size of the leak was measured as 1/64-inch diameter hole in the side seam weld. This was not sent for metallurgical analysis as it appeared to have the same characteristics as a previous stopple side seam failure depicting weld defects with lack of fusion and lack of penetration of the weld. To further investigate this threat, we have initiated a program to excavate and inspect high priority stopples on our mainline. This effort started in november of 2025 and is currently ongoing. In addition, we have identified similar style stopple tees and plan to remove upwards of 56 stopples over the course of 2026.
| Report Received Date | 2025-09-24 00:00:00 |
|---|---|
| Iyear | 2025 |
| Report Number | 20250230 |
| Supplemental Number | 41579 |
| Report Type | Supplemental Final |
| Operator Id | 10012 PHMSA Enforcement |
| Name | Nustar Pipeline Operating Partnership L.p. |
| Operator Street Address | 8111 Westchester Drive |
| Operator City Name | Dallas |
| Operator State Abbreviation | TX |
| Operator Postal Code | 75225 |
| Local Datetime | 2025-08-26 09:20:00 |
| Time Zone | Central |
| Daylight Savings Ind | Yes |
| Location Latitude | 30.49683 Google Maps OpenStreetMap |
| Location Longitude | -91.62127 Google Maps OpenStreetMap |
| Commodity Released Type | Hvl Or Other Flammable Or Toxic Fluid Which Is A Gas At Ambient Conditions |
| Commodity Subtype | Anhydrous Ammonia |
| Unintentional Release Bbls | 1.48 |
| Intentional Release Bbls | 0 |
| Recovered Bbls | 0 |
| Fatality Ind | No |
| Fatal | 0 |
| Injury Ind | No |
| Injure | 0 |
| Accident Identifier | Notification From Public |
| Incident Identified Datetime | 2025-08-26 11:48:00 |
| System Part Involved | Onshore Pipeline, Including Valve Sites |
| On Off Shore | Onshore |
| Status When Identified | Normal Operation, Includes Pauses Between Batches And During Maintenance |
| Shutdown Due Accident Ind | Yes |
| Shutdown Datetime | 2025-08-26 09:36:00 |
| Restart Datetime | 2025-08-28 18:00:00 |
| Communication State Fed Ind | No |
| On Site Datetime | 2025-08-26 11:48:00 |
| Confirmed Discovery Datetime | 2025-08-26 11:48:00 |
| Nrc Rpt Datetime | 2025-08-26 12:29:00 |
| Nrc Rpt Num | 1440940 NRC Report How to search |
| Additional Nrc Report Numbers | 1441114 |
| Ignite Ind | No |
| Upstream Action Taken | Valve Closure |
| Upstream Valve Close Datetime | 2025-08-26 09:36:00 |
| Upstream Valve Type Ind | Remotely Controlled |
| Downstream Action Taken | Valve Closure |
| Downstream Vlv Close Datetime | 2025-08-26 09:36:00 |
| Downstream Valve Type Ind | Remotely Controlled |
| Num Pub Evacuated | 0 |
| Pipe Fac Name | Donaldsonville Jct. To Marksville Station |
| Segment Name | Ramah Station 8-Inch To Palmetto Station |
| Onshore State Abbreviation | La |
| Onshore Postal Code | 70750 |
| Onshore City Name | Not Within A Municipality |
| Onshore County Name | Iberville |
| Designated Location | Survey Station No. |
| Designated Name | 3041+22 |
| Federal | Yes |
| Location Type | Pipeline Right-Of-Way |
| Incident Area Type | Underground |
| Incident Area Subtype | Under Soil |
| Depth Of Cover | 54 |
| Crossing | No |
| Pipe Facility Type | Interstate |
| Item Involved | Tap Fitting(Stopple, Thread-O-Ring, Weld-O-Let, Etc.) |
| Installation Year | 1997 |
| Manufactured Year | Unknown |
| Material Involved | Carbon Steel |
| Release Type | Leak |
| Leak Type | Other |
| Leak Type Other | Side Seam Failed - Stopple Tee |
| Wildlife Impact Ind | No |
| Soil Contamination | Yes |
| Long Term Assessment | No |
| Remediation Ind | No |
| Water Contam Ind | No |
| Could Be Hca | Yes |
| Commodity Reached Hca | No |
| Est Cost Oper Paid | 0 |
| Est Cost Gas Released | 100 |
| Est Cost Prop Damage | 22600 |
| Est Cost Emergency | 0 |
| Est Cost Environmental | 0 |
| Est Cost Other | 0 |
| Prpty | 22700 |
| Num Persons Hosp Not Ovnght | 0 |
| Num Injured Treated By Emt | 0 |
| Num Resident Building Affctd | 0 |
| Num Business Building Affctd | 0 |
| Accident Psig | 717 |
| Mop Psig | 1340 |
| Mop Cfr Section | Subpart E Pressure Test �195.406(A)(3) View CFR 49 §192 |
| Maop Established Date | 1969-03-15 00:00:00 |
| Maop Reversal Flow Ind | No |
| Accident Pressure | Pressure Did Not Exceed Mop |
| Pressure Restriction Ind | No |
| Length Segment Isolated | 10479 |
| Internal Inspection Ind | Yes |
| Operation Complications Ind | Yes |
| Incompat Commod Ind | Yes |
| Pipeline Function | > 20% Smys Regulated Transmission |
| Scada In Place Ind | Yes |
| Scada Operating Ind | Yes |
| Scada Functional Ind | Yes |
| Scada Detection Ind | No |
| Scada Conf Ind | No |
| Cpm In Place Ind | Yes |
| Cpm Operating Ind | Yes |
| Cpm Functional Ind | Yes |
| Cpm Detection Ind | No |
| Cpm Conf Ind | No |
| 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 leak coming from the stopple tee was small enough it rendered the leak un-detectable by the control room (scada/crm) |
| Employee Drug Test Ind | No |
| Contractor Drug Test Ind | No |
| Cause | Equipment Failure |
| Cause Details | Malfunction Of Control/relief Equipment |
| Eq Failure Type | Malfunction Of Control/relief Equipment |
| Stopple Control Fitting Ind | Yes |
| Eq Additional Other Ind | Yes |
| Eq Additional Other Details | Side Seam Weld On Stopple Tee. |
| Preparer Name | D** T****** |
| Preparer Title | Sr Manager - Health And Safety |
| Preparer Email | D**********@s*****.com |
| Preparer Telephone | 3167217056 |
| Prepared Date | 2025-11-13 00:00:00 |
| Local Contact Name | D** T****** |
| Local Contact Email | D**********@s*****.com |
| Local Contact Telephone | 3167217056 |
| Authorizer Name | D** T****** |
| Authorizer Telephone | 3167217056 |
| Authorizer Title | Sr Manager - Health And Safety |
| Authorizer Email | D**********@s*****.com |
| Narrative | A hunter came upon an area of dead vegetation and an ammonia odor and called the control center around 9:20am on 8/26. The pipeline was shutdown out of precaution and local personnel were dispatched and arrived onsite and confirmed a release at 11:48am. All agency notifications were made. The maintenance crew was dispatched and began excavating on 8/28 and found a split seam on a stopple tee that caused the release. The leak was stopped at 12:50pm on the 28th. A calculated amount of 1.48bbls (324lbs) was released. **update** the size of the leak was measured as 1/64-inch diameter hole in the side seam weld. This was not sent for metallurgical analysis as it appeared to have the same characteristics as a previous stopple side seam failure depicting weld defects with lack of fusion and lack of penetration of the weld. To further investigate this threat, we have initiated a program to excavate and inspect high priority stopples on our mainline. This effort started in november of 2025 and is currently ongoing. In addition, we have identified similar style stopple tees and plan to remove upwards of 56 stopples over the course of 2026. |
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