GTG incident on 2017-08-13 — TX

Operator
Columbia Gas Transmission, Llc
Cause
Incorrect Operation
Commodity
Natural Gas
Program
GTG
Damage and Injuries
0 fatalities 0 injuries
Property damage (nominal)
$0
Incident datetime
2017-08-13 10:00
Report number
Location
TX
Narrative
On august 12th, 2017, flat top compressor station (cs) was subject to an unintentional release of natural gas (material) resulting in gas loss of more than 3,000 mcf. Flat top is a transmission cs that is maintained by columbia gas transmission, llc (transcanada). Flat top cs is located in summers county, near the town of flat top, west virginia. After the remote shutdown of cs unit 3, material passed through a small opening of a 20 inch ball valve. Subsequently, material exited a 3 inch blowdown stack to atmosphere beginning on august 12th, 2017 at approximately 11:00 et. The pressure in the cs unit's piping slowly decreased from 770 psig until approximately 22:00 est on august 12th, 2017. At this time, the pressure stabilized at 560 psig until the leak was isolated. At approximately 09:00 est on august 13th, 2017, a passerby reported to transcanada that it appeared that material was venting through a blow-off valve at flat top cs. Immediately after this was reported, operations personnel were dispatched to investigate the situation. On august 13th, 2017, operations personnel arrived on-site at approximately 09:40 est, the unintended release of material was identified and isolated at approximately 10:15 est. Once operations personnel had isolated the leak and made the area safe, gas control was notified and immediately contacted transcanada's on-call specialist at 11:05 am on august 13th. After transcanada's on-call specialist had been notified, and gas loss calculations were determined to be greater than 3,000 mcf, the event was reported to the national response center. Before returning the unit back to service, the faulty valve was manually cycled from the station panel and full closure was achieved. The operator then cycled the valve once more to ensure proper functionality. No issues were discovered on the follow up investigation. A rca discovered a replaced valve actuator did not have the required torque to close a a 20" ball valve. A new actuator will be installed in 2018. Until a new actuator is installed, scada warning tags will be used to alert gas control an employee will need to be present to observe the valve closure when unit 3 is shutdown.
Detailed record list
Report Received Date
2017-09-06 00:00:00
Iyear
2017
Report Number
20170076
Supplemental Number
17550
Report Type
Supplemental Final
Operator Id
Name
Columbia Gas Transmission, Llc
Operator Street Address
700 Louisiana St. Suite 700
Operator City Name
Houston
Operator State Abbreviation
TX
Operator Postal Code
77002
Local Datetime
2017-08-12 11:00:00
Location Latitude
Location Longitude
Nrc Rpt Num
Nrc Rpt Datetime
2017-08-13 12:03:00
Commodity Released Type
Natural Gas
Unintentional Release
61800
Intentional Release
0
Accompanying Liquid
0
Fatality Ind
No
Fatal
0
Injury Ind
No
Injure
0
Shutdown Due Accident Ind
Yes
Shutdown Datetime
2017-08-13 10:15:00
Restart Datetime
2017-08-13 11:00:00
Ignite Ind
No
Explode Ind
No
Num Pub Evacuated
0
Incident Identified Datetime
2017-08-13 10:00:00
On Site Datetime
2017-08-13 09:40:00
On Off Shore
Onshore
Onshore State Abbreviation
Wv
Onshore Postal Code
25841
Onshore City Name
Flat Top
Onshore County Name
Summers
Designated Location
Milepost
Designated Name
Blowdown Vlv
Pipe Fac Name
Flat Top Compressor Station
Segment Name
Line Ka And Line Ka-Loop
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
1998
Material Involved
Carbon Steel
Release Type
Other
Release Type Details
Partial Closure Of A Compressor Station Unit's 20 Inch Ball Valve, Resulting In Natural Gas Exiting Through A 3 Inch Blow-Off Valve To Atmosphere
Class Location Type
Class 2 Location
Could Be Hca
No
Pir Radius
521
Heat Damage Ind
No
Non Heat Damage Ind
No
Hca Fatalities Ind
No
Est Cost Oper Paid
0
Est Cost Unintentional Release
171804
Est Cost Intentional Release
0
Est Cost Prop Damage
0
Est Cost Emergency
0
Est Cost Other
0
Prpty
171804
Accident Psig
770
Mop Psig
1000
Mop Cfr Section
192.619(A)(2)
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
No
Scada Conf Ind
No
Accident Identifier
Notification From Public
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 ball valve partial closure was not due to any involvements by gas control personnel
Employee Drug Test Ind
No
Contractor Drug Test Ind
No
Cause
Incorrect Operation
Cause Details
Wrong Equipment Specified Or Installed
Operation Type
Wrong Equipment Specified Or Installed
Related Other Ind
Yes
Operation Related Details
Valve Operator Did Not Have Sufficient Torque To Reliable Close The 20 Inch Ball Valve. This Valve Closes When Compressor Unit Is Taken Off Line/shutdown.
Category Type
Normal Operating Conditions
Operator Qualification Ind
No
Preparer Name
M*** N*****
Preparer Title
Compliance Specialist - U.s. Regulatory Compliance
Preparer Email
M**********@t**********.com
Preparer Telephone
(304) 722-8475
Preparer Fax
(304) 722-8420
Authorizer Name
H***** R*****
Authorizer Title
Manager - U.s. Regulatory Compliance
Authorizer Telephone
(832) 320-5315
Authorizer Email
L*********@t**********.com
Narrative
On august 12th, 2017, flat top compressor station (cs) was subject to an unintentional release of natural gas (material) resulting in gas loss of more than 3,000 mcf. Flat top is a transmission cs that is maintained by columbia gas transmission, llc (transcanada). Flat top cs is located in summers county, near the town of flat top, west virginia. After the remote shutdown of cs unit 3, material passed through a small opening of a 20 inch ball valve. Subsequently, material exited a 3 inch blowdown stack to atmosphere beginning on august 12th, 2017 at approximately 11:00 et. The pressure in the cs unit's piping slowly decreased from 770 psig until approximately 22:00 est on august 12th, 2017. At this time, the pressure stabilized at 560 psig until the leak was isolated. At approximately 09:00 est on august 13th, 2017, a passerby reported to transcanada that it appeared that material was venting through a blow-off valve at flat top cs. Immediately after this was reported, operations personnel were dispatched to investigate the situation. On august 13th, 2017, operations personnel arrived on-site at approximately 09:40 est, the unintended release of material was identified and isolated at approximately 10:15 est. Once operations personnel had isolated the leak and made the area safe, gas control was notified and immediately contacted transcanada's on-call specialist at 11:05 am on august 13th. After transcanada's on-call specialist had been notified, and gas loss calculations were determined to be greater than 3,000 mcf, the event was reported to the national response center. Before returning the unit back to service, the faulty valve was manually cycled from the station panel and full closure was achieved. The operator then cycled the valve once more to ensure proper functionality. No issues were discovered on the follow up investigation. A rca discovered a replaced valve actuator did not have the required torque to close a a 20" ball valve. A new actuator will be installed in 2018. Until a new actuator is installed, scada warning tags will be used to alert gas control an employee will need to be present to observe the valve closure when unit 3 is shutdown.
Report Received Date 2017-09-06 00:00:00
Iyear 2017
Report Number 20170076
Supplemental Number 17550
Report Type Supplemental Final
Operator Id 2616 PHMSA Enforcement
Name Columbia Gas Transmission, Llc
Operator Street Address 700 Louisiana St. Suite 700
Operator City Name Houston
Operator State Abbreviation TX
Operator Postal Code 77002
Local Datetime 2017-08-12 11:00:00
Location Latitude 37.588506 Google Maps OpenStreetMap
Location Longitude -81.092117 Google Maps OpenStreetMap
Nrc Rpt Num 1187079 NRC Report How to search
Nrc Rpt Datetime 2017-08-13 12:03:00
Commodity Released Type Natural Gas
Unintentional Release 61800
Intentional Release 0
Accompanying Liquid 0
Fatality Ind No
Fatal 0
Injury Ind No
Injure 0
Shutdown Due Accident Ind Yes
Shutdown Datetime 2017-08-13 10:15:00
Restart Datetime 2017-08-13 11:00:00
Ignite Ind No
Explode Ind No
Num Pub Evacuated 0
Incident Identified Datetime 2017-08-13 10:00:00
On Site Datetime 2017-08-13 09:40:00
On Off Shore Onshore
Onshore State Abbreviation Wv
Onshore Postal Code 25841
Onshore City Name Flat Top
Onshore County Name Summers
Designated Location Milepost
Designated Name Blowdown Vlv
Pipe Fac Name Flat Top Compressor Station
Segment Name Line Ka And Line Ka-Loop
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 1998
Material Involved Carbon Steel
Release Type Other
Release Type Details Partial Closure Of A Compressor Station Unit's 20 Inch Ball Valve, Resulting In Natural Gas Exiting Through A 3 Inch Blow-Off Valve To Atmosphere
Class Location Type Class 2 Location
Could Be Hca No
Pir Radius 521
Heat Damage Ind No
Non Heat Damage Ind No
Hca Fatalities Ind No
Est Cost Oper Paid 0
Est Cost Unintentional Release 171804
Est Cost Intentional Release 0
Est Cost Prop Damage 0
Est Cost Emergency 0
Est Cost Other 0
Prpty 171804
Accident Psig 770
Mop Psig 1000
Mop Cfr Section 192.619(A)(2) 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 No
Scada Conf Ind No
Accident Identifier Notification From Public
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 ball valve partial closure was not due to any involvements by gas control personnel
Employee Drug Test Ind No
Contractor Drug Test Ind No
Cause Incorrect Operation
Cause Details Wrong Equipment Specified Or Installed
Operation Type Wrong Equipment Specified Or Installed
Related Other Ind Yes
Operation Related Details Valve Operator Did Not Have Sufficient Torque To Reliable Close The 20 Inch Ball Valve. This Valve Closes When Compressor Unit Is Taken Off Line/shutdown.
Category Type Normal Operating Conditions
Operator Qualification Ind No
Preparer Name M*** N*****
Preparer Title Compliance Specialist - U.s. Regulatory Compliance
Preparer Email M**********@t**********.com
Preparer Telephone (304) 722-8475
Preparer Fax (304) 722-8420
Authorizer Name H***** R*****
Authorizer Title Manager - U.s. Regulatory Compliance
Authorizer Telephone (832) 320-5315
Authorizer Email L*********@t**********.com
Narrative On august 12th, 2017, flat top compressor station (cs) was subject to an unintentional release of natural gas (material) resulting in gas loss of more than 3,000 mcf. Flat top is a transmission cs that is maintained by columbia gas transmission, llc (transcanada). Flat top cs is located in summers county, near the town of flat top, west virginia. After the remote shutdown of cs unit 3, material passed through a small opening of a 20 inch ball valve. Subsequently, material exited a 3 inch blowdown stack to atmosphere beginning on august 12th, 2017 at approximately 11:00 et. The pressure in the cs unit's piping slowly decreased from 770 psig until approximately 22:00 est on august 12th, 2017. At this time, the pressure stabilized at 560 psig until the leak was isolated. At approximately 09:00 est on august 13th, 2017, a passerby reported to transcanada that it appeared that material was venting through a blow-off valve at flat top cs. Immediately after this was reported, operations personnel were dispatched to investigate the situation. On august 13th, 2017, operations personnel arrived on-site at approximately 09:40 est, the unintended release of material was identified and isolated at approximately 10:15 est. Once operations personnel had isolated the leak and made the area safe, gas control was notified and immediately contacted transcanada's on-call specialist at 11:05 am on august 13th. After transcanada's on-call specialist had been notified, and gas loss calculations were determined to be greater than 3,000 mcf, the event was reported to the national response center. Before returning the unit back to service, the faulty valve was manually cycled from the station panel and full closure was achieved. The operator then cycled the valve once more to ensure proper functionality. No issues were discovered on the follow up investigation. A rca discovered a replaced valve actuator did not have the required torque to close a a 20" ball valve. A new actuator will be installed in 2018. Until a new actuator is installed, scada warning tags will be used to alert gas control an employee will need to be present to observe the valve closure when unit 3 is shutdown.

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