GTG incident on 2017-11-22 — TX

Operator
Enable Gas Transmission, Llc
Cause
Equipment Failure
Commodity
Natural Gas
Program
GTG
Damage and Injuries
0 fatalities 0 injuries
Property damage (nominal)
$0
Incident datetime
2017-11-22 05:45
Report number
Location
TX
Narrative
During the 06:00 shift change on 11/22/17, enable gas transmission system control became aware of an unusual situation with line om-1. System control did not receive any alerts, safety related alarms, or rate of change alarms to notify them of the situation but did notice an increase in flow rate into line om-1 and a decrease in discharge pressure at dunn station. System control immediately dispatched field technicians to survey line om-1 to investigate the situation. At approximately 06:44, a 911 operator contacted system control to report a loud noise, and possible gas leak, near hwy 90 near noel, missouri. At 07:21, an enable field technician discovered a blowdown valve releasing natural gas to atmosphere at the jane compressor station. After the station was secured, scada data was checked and by 08:01 the issue had been corrected. Upon investigation, a versa valve actuator for the blowdown valve failed open due to a leak in the pilot tubing. The loose fitting was tightened eliminating the leak. The remaining valve fittings were checked at the station for tightness. On the morning of 11/22/17 enable midstream reported a potential release to the nrc (nrc #1197895 07:13), and followed up later with a location and quantity change (nrc# 1197919 12:17). The 48 hour follow up call was placed on 11/24/17 (nrc# 1197992 07:10).
Detailed record list
Report Received Date
2017-12-15 00:00:00
Iyear
2017
Report Number
20170121
Supplemental Number
17530
Report Type
Original Final
Operator Id
Name
Enable Gas Transmission, Llc
Operator Street Address
1300 Main Street
Operator City Name
Houston
Operator State Abbreviation
TX
Operator Postal Code
77002
Local Datetime
2017-11-22 05:21:00
Location Latitude
Location Longitude
-94.38231801
Nrc Rpt Num
Nrc Rpt Datetime
2017-11-22 07:13:00
Commodity Released Type
Natural Gas
Unintentional Release
21095
Intentional Release
0
Accompanying Liquid
0
Fatality Ind
No
Fatal
0
Injury Ind
No
Injure
0
Shutdown Due Accident Ind
No
Shutdown Explain
Adjustments Made To Pilot Tubing Connection While Online.
Ignite Ind
No
Explode Ind
No
Num Pub Evacuated
0
Incident Identified Datetime
2017-11-22 05:45:00
On Site Datetime
2017-11-22 07:21:00
On Off Shore
Onshore
Onshore State Abbreviation
Mo
Onshore Postal Code
64854
Onshore City Name
Noel
Onshore County Name
Mcdonald
Designated Location
Milepost
Pipe Fac Name
Jane Compressor Station
Segment Name
Line Om-1
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
Installation Year
Unknown
Material Involved
Carbon Steel
Release Type
Leak
Leak Type
Connection Failure
Class Location Type
Class 1 Location
Could Be Hca
No
Pir Radius
436
Heat Damage Ind
No
Non Heat Damage Ind
No
Hca Fatalities Ind
No
Est Cost Oper Paid
0
Est Cost Unintentional Release
67576
Est Cost Intentional Release
0
Est Cost Prop Damage
0
Est Cost Emergency
1000
Est Cost Other
0
Prpty
68576
Accident Psig
821
Mop Psig
1000
Mop Cfr Section
192.619(A)(1)
Accident Pressure
Pressure Did Not Exceed Maop
Pressure Restriction Ind
No
Pipeline Function
Transmission System
Scada In Place Ind
Yes
Scada Operating Ind
Yes
Scada Functional Ind
Yes
Scada Detection Ind
Yes
Scada Conf Ind
Yes
Accident Identifier
Scada-Based Information (Such As Alarm(S), Alert(S), Event(S), And/or Volume Or Pack Calculations)
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
Malfunction of a component caused a versa valve to fail open.
Employee Drug Test Ind
No
Contractor Drug Test Ind
No
Cause
Equipment Failure
Cause Details
Threaded Connection/coupling Failure
Eq Failure Type
Threaded Connection/coupling Failure
Other Stripped Ind
Threaded Fitting
Additional Vibration Ind
Yes
Preparer Name
C**** R******
Preparer Title
Lead Dot Compliance Program Manager
Preparer Email
C************@e**************.com
Preparer Telephone
405 558 4647
Authorizer Name
C**** R******
Authorizer Title
Lead Dot Compliance Program Manager
Authorizer Telephone
405 558 4647
Authorizer Email
C************@e**************.com
Narrative
During the 06:00 shift change on 11/22/17, enable gas transmission system control became aware of an unusual situation with line om-1. System control did not receive any alerts, safety related alarms, or rate of change alarms to notify them of the situation but did notice an increase in flow rate into line om-1 and a decrease in discharge pressure at dunn station. System control immediately dispatched field technicians to survey line om-1 to investigate the situation. At approximately 06:44, a 911 operator contacted system control to report a loud noise, and possible gas leak, near hwy 90 near noel, missouri. At 07:21, an enable field technician discovered a blowdown valve releasing natural gas to atmosphere at the jane compressor station. After the station was secured, scada data was checked and by 08:01 the issue had been corrected. Upon investigation, a versa valve actuator for the blowdown valve failed open due to a leak in the pilot tubing. The loose fitting was tightened eliminating the leak. The remaining valve fittings were checked at the station for tightness. On the morning of 11/22/17 enable midstream reported a potential release to the nrc (nrc #1197895 07:13), and followed up later with a location and quantity change (nrc# 1197919 12:17). The 48 hour follow up call was placed on 11/24/17 (nrc# 1197992 07:10).
Report Received Date 2017-12-15 00:00:00
Iyear 2017
Report Number 20170121
Supplemental Number 17530
Report Type Original Final
Operator Id 602 PHMSA Enforcement
Name Enable Gas Transmission, Llc
Operator Street Address 1300 Main Street
Operator City Name Houston
Operator State Abbreviation TX
Operator Postal Code 77002
Local Datetime 2017-11-22 05:21:00
Location Latitude 36.52811701 Google Maps OpenStreetMap
Location Longitude -94.38231801 Google Maps OpenStreetMap
Nrc Rpt Num 1197895 NRC Report How to search
Nrc Rpt Datetime 2017-11-22 07:13:00
Commodity Released Type Natural Gas
Unintentional Release 21095
Intentional Release 0
Accompanying Liquid 0
Fatality Ind No
Fatal 0
Injury Ind No
Injure 0
Shutdown Due Accident Ind No
Shutdown Explain Adjustments Made To Pilot Tubing Connection While Online.
Ignite Ind No
Explode Ind No
Num Pub Evacuated 0
Incident Identified Datetime 2017-11-22 05:45:00
On Site Datetime 2017-11-22 07:21:00
On Off Shore Onshore
Onshore State Abbreviation Mo
Onshore Postal Code 64854
Onshore City Name Noel
Onshore County Name Mcdonald
Designated Location Milepost
Pipe Fac Name Jane Compressor Station
Segment Name Line Om-1
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
Installation Year Unknown
Material Involved Carbon Steel
Release Type Leak
Leak Type Connection Failure
Class Location Type Class 1 Location
Could Be Hca No
Pir Radius 436
Heat Damage Ind No
Non Heat Damage Ind No
Hca Fatalities Ind No
Est Cost Oper Paid 0
Est Cost Unintentional Release 67576
Est Cost Intentional Release 0
Est Cost Prop Damage 0
Est Cost Emergency 1000
Est Cost Other 0
Prpty 68576
Accident Psig 821
Mop Psig 1000
Mop Cfr Section 192.619(A)(1) View CFR 49 §192
Accident Pressure Pressure Did Not Exceed Maop
Pressure Restriction Ind No
Pipeline Function Transmission System
Scada In Place Ind Yes
Scada Operating Ind Yes
Scada Functional Ind Yes
Scada Detection Ind Yes
Scada Conf Ind Yes
Accident Identifier Scada-Based Information (Such As Alarm(S), Alert(S), Event(S), And/or Volume Or Pack Calculations)
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 Malfunction of a component caused a versa valve to fail open.
Employee Drug Test Ind No
Contractor Drug Test Ind No
Cause Equipment Failure
Cause Details Threaded Connection/coupling Failure
Eq Failure Type Threaded Connection/coupling Failure
Other Stripped Ind Threaded Fitting
Additional Vibration Ind Yes
Preparer Name C**** R******
Preparer Title Lead Dot Compliance Program Manager
Preparer Email C************@e**************.com
Preparer Telephone 405 558 4647
Authorizer Name C**** R******
Authorizer Title Lead Dot Compliance Program Manager
Authorizer Telephone 405 558 4647
Authorizer Email C************@e**************.com
Narrative During the 06:00 shift change on 11/22/17, enable gas transmission system control became aware of an unusual situation with line om-1. System control did not receive any alerts, safety related alarms, or rate of change alarms to notify them of the situation but did notice an increase in flow rate into line om-1 and a decrease in discharge pressure at dunn station. System control immediately dispatched field technicians to survey line om-1 to investigate the situation. At approximately 06:44, a 911 operator contacted system control to report a loud noise, and possible gas leak, near hwy 90 near noel, missouri. At 07:21, an enable field technician discovered a blowdown valve releasing natural gas to atmosphere at the jane compressor station. After the station was secured, scada data was checked and by 08:01 the issue had been corrected. Upon investigation, a versa valve actuator for the blowdown valve failed open due to a leak in the pilot tubing. The loose fitting was tightened eliminating the leak. The remaining valve fittings were checked at the station for tightness. On the morning of 11/22/17 enable midstream reported a potential release to the nrc (nrc #1197895 07:13), and followed up later with a location and quantity change (nrc# 1197919 12:17). The 48 hour follow up call was placed on 11/24/17 (nrc# 1197992 07:10).

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