Incident details
Operator, cause, commodity and consequences with raw source fields.
GTG incident on 2025-07-03 — OK
Operator
Mountainwest Pipeline, Llc
Cause
Equipment Failure
Commodity
Natural Gas
Program
GTG
Damage and Injuries
0 fatalities
0 injuries
Property damage (nominal)
$750,000
Incident datetime
2025-07-03 00:00 UTC
Report number
Location
OK
Narrative
On june 6th 2025 12:11pm mst clay basin cs unit 1 automatically shutdown due to simultaneous high turbo vibration and engine vibration alarms. Approximately 32 seconds later, gas was detected in the building, triggering an emergency shutdown (esd) of the entire station. One field personnel was present in the compressor building, but not in the vicinity of the failure. The unit 1 compressor crosshead shoe separated from the crosshead and was jammed into the crosshead causing the frame to break. The compressor rod was bent as a part of the failure destroying the gas packing causing a gas release to occur. Incident investigation is ongoing. Preliminary indications points towards contributing factor of a bolt and stud failure that caused the shoe to be loose. Action taken during the interim of the investigation was all other units at kastler cs were inspected to ensure all crosshead nuts had not been loosened.
Detailed record list
Report Received Date
2025-07-03 00:00:00
Iyear
2025
Report Number
20250076
Supplemental Number
41112
Report Type
Original
Operator Id
12874
Name
Mountainwest Pipeline, Llc
Operator Street Address
One Williams Center
Operator City Name
Tulsa
Operator State Abbreviation
OK
Operator Postal Code
74172
Time Zone
Mountain
Daylight Savings Ind
Yes
Location Latitude
40.99583
Location Longitude
-109.2125
Nrc Rpt Num
1433328
Additional Nrc Report Numbers
1433378
Commodity Released Type
Natural Gas
Unintentional Release
0.01
Intentional Release
291
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
Yes
Communication State Fed Ind
No
Ignite Ind
No
Num Pub Evacuated
0
On Off Shore
Onshore
Onshore State Abbreviation
Ut
Onshore Postal Code
84023
Onshore City Name
Not Within A Municipality
Onshore County Name
Daggett
Designated Location
Not Applicable
Pipe Fac Name
Kastler Cs
Segment Name
Compressor Unit 1
Federal
No
Location Type
Operator-Controlled Property
Incident Area Type
Aboveground
Incident Area Subtype
Inside A Building
Crossing
No
Pipe Facility Type
Interstate
System Part Involved
Onshore Compressor Station Equipment And Piping
Item Involved
Compressor
Installation Year
1978
Manufactured Year
1977
Material Involved
Carbon Steel
Release Type
Rupture
Rupture Orient
Circumferential
Rupture Length
36
Rupture Width
24
Class Location Type
Class 1 Location
Could Be Hca
No
Pir Radius
518
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
1665
Est Cost Prop Damage
750000
Est Cost Emergency
0
Est Cost Other
0
Gas Cost In Mcf
5.72
Prpty
751665
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
730
Gas Flow In Pipe In Mcf
270000
Mop Psig
2520
Mop Cfr Section
192.619(A)(2)
Maop Established Date
2016-05-23 00:00:00
Maop Reversal Flow Ind
No
Accident Pressure
Pressure Did Not Exceed Maop
Pressure Restriction Ind
No
Gas Required Odorized Ind
No
Pipeline Function
Transmission In Storage Field
Scada In Place Ind
Yes
Scada Operating Ind
Yes
Scada Functional Ind
Yes
Scada Detection Ind
No
Scada Conf Ind
Yes
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
Mechanical failure due to bolt loosening could have not been caused or contributed by actions of a controller. No actions were taken by the controller due to automated shutdown occurred.
Employee Drug Test Ind
No
Contractor Drug Test Ind
No
Cause
Equipment Failure
Cause Details
Compressor Or Compressor-Related Equipment
Eq Failure Type
Compressor Or Compressor-Related Equipment
Other Compressor Ind
Crack In Body
Additional Vibration Ind
Yes
Eqf Threaded Coupling Ind
Yes
Preparer Name
L***** H***
Preparer Title
Pipeline Safety Manager
Preparer Email
L**********@w*******.com
Preparer Telephone
9182404259
Local Contact Name
E*** A****
Local Contact Email
E*********@w*******.com
Local Contact Telephone
3077055662
Authorizer Name
L***** H***
Authorizer Title
Pipeline Safety Manager
Authorizer Telephone
9182404259
Authorizer Email
L**********@w*******.com
Narrative
On june 6th 2025 12:11pm mst clay basin cs unit 1 automatically shutdown due to simultaneous high turbo vibration and engine vibration alarms. Approximately 32 seconds later, gas was detected in the building, triggering an emergency shutdown (esd) of the entire station. One field personnel was present in the compressor building, but not in the vicinity of the failure. The unit 1 compressor crosshead shoe separated from the crosshead and was jammed into the crosshead causing the frame to break. The compressor rod was bent as a part of the failure destroying the gas packing causing a gas release to occur. Incident investigation is ongoing. Preliminary indications points towards contributing factor of a bolt and stud failure that caused the shoe to be loose. Action taken during the interim of the investigation was all other units at kastler cs were inspected to ensure all crosshead nuts had not been loosened.
| Report Received Date | 2025-07-03 00:00:00 |
|---|---|
| Iyear | 2025 |
| Report Number | 20250076 |
| Supplemental Number | 41112 |
| Report Type | Original |
| Operator Id | 12874 PHMSA Enforcement |
| Name | Mountainwest Pipeline, Llc |
| Operator Street Address | One Williams Center |
| Operator City Name | Tulsa |
| Operator State Abbreviation | OK |
| Operator Postal Code | 74172 |
| Time Zone | Mountain |
| Daylight Savings Ind | Yes |
| Location Latitude | 40.99583 Google Maps OpenStreetMap |
| Location Longitude | -109.2125 Google Maps OpenStreetMap |
| Nrc Rpt Num | 1433328 NRC Report How to search |
| Additional Nrc Report Numbers | 1433378 |
| Commodity Released Type | Natural Gas |
| Unintentional Release | 0.01 |
| Intentional Release | 291 |
| 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 | Yes |
| Communication State Fed Ind | No |
| Ignite Ind | No |
| Num Pub Evacuated | 0 |
| On Off Shore | Onshore |
| Onshore State Abbreviation | Ut |
| Onshore Postal Code | 84023 |
| Onshore City Name | Not Within A Municipality |
| Onshore County Name | Daggett |
| Designated Location | Not Applicable |
| Pipe Fac Name | Kastler Cs |
| Segment Name | Compressor Unit 1 |
| Federal | No |
| Location Type | Operator-Controlled Property |
| Incident Area Type | Aboveground |
| Incident Area Subtype | Inside A Building |
| Crossing | No |
| Pipe Facility Type | Interstate |
| System Part Involved | Onshore Compressor Station Equipment And Piping |
| Item Involved | Compressor |
| Installation Year | 1978 |
| Manufactured Year | 1977 |
| Material Involved | Carbon Steel |
| Release Type | Rupture |
| Rupture Orient | Circumferential |
| Rupture Length | 36 |
| Rupture Width | 24 |
| Class Location Type | Class 1 Location |
| Could Be Hca | No |
| Pir Radius | 518 |
| 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 | 1665 |
| Est Cost Prop Damage | 750000 |
| Est Cost Emergency | 0 |
| Est Cost Other | 0 |
| Gas Cost In Mcf | 5.72 |
| Prpty | 751665 |
| 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 | 730 |
| Gas Flow In Pipe In Mcf | 270000 |
| Mop Psig | 2520 |
| Mop Cfr Section | 192.619(A)(2) View CFR 49 §192 |
| Maop Established Date | 2016-05-23 00:00:00 |
| Maop Reversal Flow Ind | No |
| Accident Pressure | Pressure Did Not Exceed Maop |
| Pressure Restriction Ind | No |
| Gas Required Odorized Ind | No |
| Pipeline Function | Transmission In Storage Field |
| Scada In Place Ind | Yes |
| Scada Operating Ind | Yes |
| Scada Functional Ind | Yes |
| Scada Detection Ind | No |
| Scada Conf Ind | Yes |
| 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 | Mechanical failure due to bolt loosening could have not been caused or contributed by actions of a controller. No actions were taken by the controller due to automated shutdown occurred. |
| Employee Drug Test Ind | No |
| Contractor Drug Test Ind | No |
| Cause | Equipment Failure |
| Cause Details | Compressor Or Compressor-Related Equipment |
| Eq Failure Type | Compressor Or Compressor-Related Equipment |
| Other Compressor Ind | Crack In Body |
| Additional Vibration Ind | Yes |
| Eqf Threaded Coupling Ind | Yes |
| Preparer Name | L***** H*** |
| Preparer Title | Pipeline Safety Manager |
| Preparer Email | L**********@w*******.com |
| Preparer Telephone | 9182404259 |
| Local Contact Name | E*** A**** |
| Local Contact Email | E*********@w*******.com |
| Local Contact Telephone | 3077055662 |
| Authorizer Name | L***** H*** |
| Authorizer Title | Pipeline Safety Manager |
| Authorizer Telephone | 9182404259 |
| Authorizer Email | L**********@w*******.com |
| Narrative | On june 6th 2025 12:11pm mst clay basin cs unit 1 automatically shutdown due to simultaneous high turbo vibration and engine vibration alarms. Approximately 32 seconds later, gas was detected in the building, triggering an emergency shutdown (esd) of the entire station. One field personnel was present in the compressor building, but not in the vicinity of the failure. The unit 1 compressor crosshead shoe separated from the crosshead and was jammed into the crosshead causing the frame to break. The compressor rod was bent as a part of the failure destroying the gas packing causing a gas release to occur. Incident investigation is ongoing. Preliminary indications points towards contributing factor of a bolt and stud failure that caused the shoe to be loose. Action taken during the interim of the investigation was all other units at kastler cs were inspected to ensure all crosshead nuts had not been loosened. |
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