GTG incident on 2025-11-02 — NE

Operator
Northern Natural Gas Co
Cause
Equipment Failure
Commodity
Natural Gas
Program
GTG
Damage and Injuries
0 fatalities 0 injuries
Property damage (nominal)
$100
Incident datetime
2025-11-02 17:12
Report number
Location
NE
Narrative
On november 2, 2025, at 1712 hours, a senior pipeline technician, for the ogden, iowa, plant team, heard a relief valve venting from his home near the ogden, iowa, compressor station and alerted the on-call technician. The technician arrived to find compressor unit 18 relief valve venting gas. The relief valve was activated due to broken tubing that caused the dome pressure of the relief valve to go to zero psig. Additional horsepower was started to ensure throughput was met. At 1755 hours, compressor unit 18 was isolated, shut down and blown down. Once the unit was blown down repairs were made to the broken tubing, and the compressor unit was purged and made ready for service.
Detailed record list
Report Received Date
2025-11-26 00:00:00
Iyear
2025
Report Number
20250132
Supplemental Number
41630
Report Type
Original
Operator Id
Name
Northern Natural Gas Co
Operator Street Address
1111 South 103rd Street
Operator City Name
Omaha
Operator State Abbreviation
NE
Operator Postal Code
68124
Local Datetime
2025-11-02 17:12:00
Time Zone
Central
Daylight Savings Ind
No
Location Latitude
Location Longitude
Nrc Rpt Num
Nrc Rpt Datetime
2025-11-02 19:25:00
Additional Nrc Report Numbers
1447026
Commodity Released Type
Natural Gas
Unintentional Release
11490
Intentional Release
5
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
Shutdown Datetime
2025-11-02 17:55:00
Restart Datetime
2025-11-02 18:25:00
Communication State Fed Ind
No
Ignite Ind
No
Num Pub Evacuated
0
Incident Identified Datetime
2025-11-02 17:12:00
On Site Datetime
2025-11-02 17:53:00
Confirmed Discovery Datetime
2025-11-02 17:53:00
On Off Shore
Onshore
Onshore State Abbreviation
Ia
Onshore Postal Code
50212
Onshore City Name
Not Within A Municipality
Onshore County Name
Boone, County, Iowa
Designated Location
Not Applicable
Pipe Fac Name
Ogden, Iowa, Compressor Station
Segment Name
Ia-062
Federal
No
Location Type
Operator-Controlled Property
Incident Area Type
Aboveground
Incident Area Subtype
Typical Aboveground Facility Piping Or Appurtenance
Crossing
No
Pipe Facility Type
Interstate
System Part Involved
Onshore Compressor Station Equipment And Piping
Item Involved
Tubing
Tubing Material
Stainless Steel
Tubing Type
Rigid
Installation Year
Unknown
Manufactured Year
Unknown
Material Involved
Material Other Than Carbon Steel Or Plastic
Material Details
Stainless Steel Tubing
Release Type
Leak
Leak Type
Connection Failure
Class Location Type
Class 1 Location
Could Be Hca
No
Pir Radius
200
Heat Damage Ind
No
Non Heat Damage Ind
No
Did Occur In Mca Ind
No
Est Cost Oper Paid
0
Est Cost Unintentional Release
47339
Est Cost Intentional Release
21
Est Cost Prop Damage
100
Est Cost Emergency
450
Est Cost Other
0
Gas Cost In Mcf
4.12
Prpty
47910
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
884
Gas Flow In Pipe In Mcf
528000
Mop Psig
1000
Mop Cfr Section
192.619(A)(2)
Maop Established Date
1968-12-01 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 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
Yes, specify investigation result(s): (select all that apply)
Invest Schedule Ind
Yes
Invest No Control Room Ind
Yes
Invest No Controller Ind
Yes
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
Instrumentation Ind
Yes
Relief Valve Ind
Yes
Additional Vibration Ind
Yes
Additional Support Ind
Yes
Preparer Name
K**** G***
Preparer Title
Sr. Pipeline Safety Specialist
Preparer Email
K*********@n****.com
Preparer Telephone
402-398-7298
Local Contact Name
K**** G***
Local Contact Email
K*********@n****.com
Local Contact Telephone
402-398-7298
Authorizer Name
K**** G***
Authorizer Title
Sr. Pipeline Safety Specialist
Authorizer Telephone
402-398-7298
Authorizer Email
K*********@n****.com
Narrative
On november 2, 2025, at 1712 hours, a senior pipeline technician, for the ogden, iowa, plant team, heard a relief valve venting from his home near the ogden, iowa, compressor station and alerted the on-call technician. The technician arrived to find compressor unit 18 relief valve venting gas. The relief valve was activated due to broken tubing that caused the dome pressure of the relief valve to go to zero psig. Additional horsepower was started to ensure throughput was met. At 1755 hours, compressor unit 18 was isolated, shut down and blown down. Once the unit was blown down repairs were made to the broken tubing, and the compressor unit was purged and made ready for service.
Report Received Date 2025-11-26 00:00:00
Iyear 2025
Report Number 20250132
Supplemental Number 41630
Report Type Original
Operator Id 13750 PHMSA Enforcement
Name Northern Natural Gas Co
Operator Street Address 1111 South 103rd Street
Operator City Name Omaha
Operator State Abbreviation NE
Operator Postal Code 68124
Local Datetime 2025-11-02 17:12:00
Time Zone Central
Daylight Savings Ind No
Location Latitude 42.045551 Google Maps OpenStreetMap
Location Longitude -94.045408 Google Maps OpenStreetMap
Nrc Rpt Num 1446930 NRC Report How to search
Nrc Rpt Datetime 2025-11-02 19:25:00
Additional Nrc Report Numbers 1447026
Commodity Released Type Natural Gas
Unintentional Release 11490
Intentional Release 5
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
Shutdown Datetime 2025-11-02 17:55:00
Restart Datetime 2025-11-02 18:25:00
Communication State Fed Ind No
Ignite Ind No
Num Pub Evacuated 0
Incident Identified Datetime 2025-11-02 17:12:00
On Site Datetime 2025-11-02 17:53:00
Confirmed Discovery Datetime 2025-11-02 17:53:00
On Off Shore Onshore
Onshore State Abbreviation Ia
Onshore Postal Code 50212
Onshore City Name Not Within A Municipality
Onshore County Name Boone, County, Iowa
Designated Location Not Applicable
Pipe Fac Name Ogden, Iowa, Compressor Station
Segment Name Ia-062
Federal No
Location Type Operator-Controlled Property
Incident Area Type Aboveground
Incident Area Subtype Typical Aboveground Facility Piping Or Appurtenance
Crossing No
Pipe Facility Type Interstate
System Part Involved Onshore Compressor Station Equipment And Piping
Item Involved Tubing
Tubing Material Stainless Steel
Tubing Type Rigid
Installation Year Unknown
Manufactured Year Unknown
Material Involved Material Other Than Carbon Steel Or Plastic
Material Details Stainless Steel Tubing
Release Type Leak
Leak Type Connection Failure
Class Location Type Class 1 Location
Could Be Hca No
Pir Radius 200
Heat Damage Ind No
Non Heat Damage Ind No
Did Occur In Mca Ind No
Est Cost Oper Paid 0
Est Cost Unintentional Release 47339
Est Cost Intentional Release 21
Est Cost Prop Damage 100
Est Cost Emergency 450
Est Cost Other 0
Gas Cost In Mcf 4.12
Prpty 47910
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 884
Gas Flow In Pipe In Mcf 528000
Mop Psig 1000
Mop Cfr Section 192.619(A)(2) View CFR 49 §192
Maop Established Date 1968-12-01 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 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 Yes, specify investigation result(s): (select all that apply)
Invest Schedule Ind Yes
Invest No Control Room Ind Yes
Invest No Controller Ind Yes
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
Instrumentation Ind Yes
Relief Valve Ind Yes
Additional Vibration Ind Yes
Additional Support Ind Yes
Preparer Name K**** G***
Preparer Title Sr. Pipeline Safety Specialist
Preparer Email K*********@n****.com
Preparer Telephone 402-398-7298
Local Contact Name K**** G***
Local Contact Email K*********@n****.com
Local Contact Telephone 402-398-7298
Authorizer Name K**** G***
Authorizer Title Sr. Pipeline Safety Specialist
Authorizer Telephone 402-398-7298
Authorizer Email K*********@n****.com
Narrative On november 2, 2025, at 1712 hours, a senior pipeline technician, for the ogden, iowa, plant team, heard a relief valve venting from his home near the ogden, iowa, compressor station and alerted the on-call technician. The technician arrived to find compressor unit 18 relief valve venting gas. The relief valve was activated due to broken tubing that caused the dome pressure of the relief valve to go to zero psig. Additional horsepower was started to ensure throughput was met. At 1755 hours, compressor unit 18 was isolated, shut down and blown down. Once the unit was blown down repairs were made to the broken tubing, and the compressor unit was purged and made ready for service.

All rights reserved. Copyright © by ClearPHMSA