GTG incident on 2011-12-08 — TX

Operator
Columbia Gas Transmission Corp
Cause
Equipment Failure
Commodity
Natural Gas
Program
GTG
Damage and Injuries
0 fatalities 0 injuries
Property damage (nominal)
$0
Incident datetime
2011-12-08 04:54
Report number
Location
TX
Narrative
A shuttle valve had failed causing an unintended release of natural gas to vent into atmosphere via an 8-in blow-out pipe. The compressor station was shut down to stop the flow of natural gas into atmosphere and to secure the site for further investigations. An investigative team was launched to look into the probable cause of this incident. The manufacturer is assisting the company engineering team in looking into the root cause of this shuttle valve failure. Additional information will be submitted in the final incident report. Supplement/final report (submitted on 02/28/2018 by chris legg) an onsite investigation was conducted on 12/08/2011 following the incident. The esd pilot air poppet valve, which triggers the esd blowdown valve (8"), sometimes referred to a "shuttle valve", failed after it was stuck in the open position. Ed clarkson, wv psc was on-site during the investigation. During the investigation, several small leaks were located around tubing fittings in the pilot airline. Possible that pilot line vented between a freeze point and the tubing leaks, which then allowed the actuator to go open. The pilot airline was disassembled, but no obvious signs of a freeze or other blockage was seen. The other possibility was that liquids in the power gas froze inside the poppet valve assembly and forced the poppet valve open, which then caused the actuator to go open. As a response to the failure, the esd pilot air poppet valve on the actuator was rebuilt and further inspected on 12/13/2011 (maximo work order#: b2568587). As a preventative measure, all of the other esd pilot air poppet valves at the station were also later rebuild.
Detailed record list
Report Received Date
2012-01-07 00:00:00
Iyear
2011
Report Number
20120004
Supplemental Number
17622
Report Type
Supplemental Final
Operator Id
Name
Columbia Gas Transmission Corp
Operator Street Address
700 Louisiana St. Suite 700
Operator City Name
Houston
Operator State Abbreviation
TX
Operator Postal Code
77002
Local Datetime
2011-12-08 04:45:00
Location Latitude
Location Longitude
Nrc Rpt Num
Nrc Rpt Datetime
2011-12-08 08:35:00
Commodity Released Type
Natural Gas
Unintentional Release
16424
Intentional Release
0
Accompanying Liquid
0
Fatality Ind
No
Fatal
0
Injury Ind
No
Injure
0
Shutdown Due Accident Ind
No
Shutdown Explain
Ripley Compressor Station Was Shut Down
Ignite Ind
No
Explode Ind
No
Num Pub Evacuated
0
Incident Identified Datetime
2011-12-08 04:54:00
On Site Datetime
2011-12-08 05:37:00
On Off Shore
Onshore
Onshore State Abbreviation
Wv
Onshore Postal Code
25271
Onshore City Name
Ripley
Onshore County Name
Jackson
Designated Location
Milepost
Designated Name
Compressor St
Pipe Fac Name
Ripley Compressor Station
Segment Name
Ripley
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
Valve
Valve Type
Auxiliary Or Other Valve
Installation Year
Unknown
Material Involved
Carbon Steel
Release Type
Other
Release Type Details
Mechanical Failure
Class Location Type
Class 1 Location
Could Be Hca
No
Pir Radius
227
Heat Damage Ind
No
Non Heat Damage Ind
No
Hca Fatalities Ind
No
Est Cost Oper Paid
0
Est Cost Unintentional Release
56006
Est Cost Intentional Release
0
Est Cost Prop Damage
0
Est Cost Emergency
0
Est Cost Other
0
Prpty
56006
Accident Psig
732
Mop Psig
1700
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
Other
Accident Details
Coinciding Reporting By Both Gas Controller And 911 Dispatcher
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
All systems in the control room were functioning normally. Alarm was set off; action was taken by the controller as per training. Monitoring center was notified and a confirmation was given to the monitoring center (at the same time) by the jackson county 911 dispatcher about the incident confirming the controller's identification to this pressure drop.
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
Other Control Relief Ind
Yes
Other Control Relief Details
Esd Pilot Air Poppet Valve, Which Triggers The Esd Blowdown Valve (8"), Sometimes Referred To A "shuttle Valve" Failed After It Was Stuck In The Open Position.
Eq Additional Other Ind
Yes
Eq Additional Other Details
Probable Moistureness In Shuttle Valve
Preparer Name
C**** L***
Preparer Title
Regional Regulatory Compliance Specialist
Preparer Email
C*********@t**********.com
Preparer Telephone
304-722-8530
Authorizer Name
H***** L** R*****
Authorizer Title
Manager Us Regulatory Compliance
Authorizer Telephone
832-320-5315
Authorizer Email
L*********@t**********.com
Narrative
A shuttle valve had failed causing an unintended release of natural gas to vent into atmosphere via an 8-in blow-out pipe. The compressor station was shut down to stop the flow of natural gas into atmosphere and to secure the site for further investigations. An investigative team was launched to look into the probable cause of this incident. The manufacturer is assisting the company engineering team in looking into the root cause of this shuttle valve failure. Additional information will be submitted in the final incident report. Supplement/final report (submitted on 02/28/2018 by chris legg) an onsite investigation was conducted on 12/08/2011 following the incident. The esd pilot air poppet valve, which triggers the esd blowdown valve (8"), sometimes referred to a "shuttle valve", failed after it was stuck in the open position. Ed clarkson, wv psc was on-site during the investigation. During the investigation, several small leaks were located around tubing fittings in the pilot airline. Possible that pilot line vented between a freeze point and the tubing leaks, which then allowed the actuator to go open. The pilot airline was disassembled, but no obvious signs of a freeze or other blockage was seen. The other possibility was that liquids in the power gas froze inside the poppet valve assembly and forced the poppet valve open, which then caused the actuator to go open. As a response to the failure, the esd pilot air poppet valve on the actuator was rebuilt and further inspected on 12/13/2011 (maximo work order#: b2568587). As a preventative measure, all of the other esd pilot air poppet valves at the station were also later rebuild.
Report Received Date 2012-01-07 00:00:00
Iyear 2011
Report Number 20120004
Supplemental Number 17622
Report Type Supplemental Final
Operator Id 2616 PHMSA Enforcement
Name Columbia Gas Transmission Corp
Operator Street Address 700 Louisiana St. Suite 700
Operator City Name Houston
Operator State Abbreviation TX
Operator Postal Code 77002
Local Datetime 2011-12-08 04:45:00
Location Latitude 38.877689 Google Maps OpenStreetMap
Location Longitude -81.690931 Google Maps OpenStreetMap
Nrc Rpt Num 997496 NRC Report How to search
Nrc Rpt Datetime 2011-12-08 08:35:00
Commodity Released Type Natural Gas
Unintentional Release 16424
Intentional Release 0
Accompanying Liquid 0
Fatality Ind No
Fatal 0
Injury Ind No
Injure 0
Shutdown Due Accident Ind No
Shutdown Explain Ripley Compressor Station Was Shut Down
Ignite Ind No
Explode Ind No
Num Pub Evacuated 0
Incident Identified Datetime 2011-12-08 04:54:00
On Site Datetime 2011-12-08 05:37:00
On Off Shore Onshore
Onshore State Abbreviation Wv
Onshore Postal Code 25271
Onshore City Name Ripley
Onshore County Name Jackson
Designated Location Milepost
Designated Name Compressor St
Pipe Fac Name Ripley Compressor Station
Segment Name Ripley
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 Valve
Valve Type Auxiliary Or Other Valve
Installation Year Unknown
Material Involved Carbon Steel
Release Type Other
Release Type Details Mechanical Failure
Class Location Type Class 1 Location
Could Be Hca No
Pir Radius 227
Heat Damage Ind No
Non Heat Damage Ind No
Hca Fatalities Ind No
Est Cost Oper Paid 0
Est Cost Unintentional Release 56006
Est Cost Intentional Release 0
Est Cost Prop Damage 0
Est Cost Emergency 0
Est Cost Other 0
Prpty 56006
Accident Psig 732
Mop Psig 1700
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 Other
Accident Details Coinciding Reporting By Both Gas Controller And 911 Dispatcher
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 All systems in the control room were functioning normally. Alarm was set off; action was taken by the controller as per training. Monitoring center was notified and a confirmation was given to the monitoring center (at the same time) by the jackson county 911 dispatcher about the incident confirming the controller's identification to this pressure drop.
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
Other Control Relief Ind Yes
Other Control Relief Details Esd Pilot Air Poppet Valve, Which Triggers The Esd Blowdown Valve (8"), Sometimes Referred To A "shuttle Valve" Failed After It Was Stuck In The Open Position.
Eq Additional Other Ind Yes
Eq Additional Other Details Probable Moistureness In Shuttle Valve
Preparer Name C**** L***
Preparer Title Regional Regulatory Compliance Specialist
Preparer Email C*********@t**********.com
Preparer Telephone 304-722-8530
Authorizer Name H***** L** R*****
Authorizer Title Manager Us Regulatory Compliance
Authorizer Telephone 832-320-5315
Authorizer Email L*********@t**********.com
Narrative A shuttle valve had failed causing an unintended release of natural gas to vent into atmosphere via an 8-in blow-out pipe. The compressor station was shut down to stop the flow of natural gas into atmosphere and to secure the site for further investigations. An investigative team was launched to look into the probable cause of this incident. The manufacturer is assisting the company engineering team in looking into the root cause of this shuttle valve failure. Additional information will be submitted in the final incident report. Supplement/final report (submitted on 02/28/2018 by chris legg) an onsite investigation was conducted on 12/08/2011 following the incident. The esd pilot air poppet valve, which triggers the esd blowdown valve (8"), sometimes referred to a "shuttle valve", failed after it was stuck in the open position. Ed clarkson, wv psc was on-site during the investigation. During the investigation, several small leaks were located around tubing fittings in the pilot airline. Possible that pilot line vented between a freeze point and the tubing leaks, which then allowed the actuator to go open. The pilot airline was disassembled, but no obvious signs of a freeze or other blockage was seen. The other possibility was that liquids in the power gas froze inside the poppet valve assembly and forced the poppet valve open, which then caused the actuator to go open. As a response to the failure, the esd pilot air poppet valve on the actuator was rebuilt and further inspected on 12/13/2011 (maximo work order#: b2568587). As a preventative measure, all of the other esd pilot air poppet valves at the station were also later rebuild.

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