Incident details
Operator, cause, commodity and consequences with raw source fields.
GTG incident on 2015-11-23 — TX
Operator
Columbia Gas Transmission, Llc
Cause
Equipment Failure
Commodity
Natural Gas
Program
GTG
Damage and Injuries
0 fatalities
0 injuries
Property damage (nominal)
$0
Incident datetime
2015-11-23 06:34
Report number
Location
TX
Narrative
On november 23, 2015, a columbia gas transmission, llc (columbia) facility was subject to an event that involved an unintended activation of an 8-in blow-off (bo) valve. This bo valve is located in ripley compressor station (cs) yard. Ripley cs is a transmission facility located near the town of sandyville, jackson county, west virginia is owned, operated and maintained by columbia. Columbia operations personnel responded to this event and isolated the bo valve with its respective pipeline preventing additional unintended release of natural gas (material) into atmosphere. There was no presence of fire, explosion or evacuations in lieu of the material release. The initial assessment indicated that presence of accumulated moisture played a contributing factor in the chain of events that led to this incident. The emergency shutdown (esd) system trigger pneumatic pressure on that actuator bled down below the required pressure to hold the valve closed. The esd pneumatic pressure to all other esd valves remained at its full system pressure. An accumulation of approximately 2 gallons of accumulated moisture was drained from the esd trigger pneumatic supply tank, that is located directly downstream of the facility's air dryer system. A vendor technician was on site the following day of the incident where a full assessment to the air dryer followed. The vendor's technician identified that the air dryer system's automatic control system was locked-up. A manual switching operation was performed to enable the full operation of the two air dryer system towers. The root cause analysis (rca) report concluded that moisture collected in the esd trigger pneumatic tubing froze which allowed the pressure on the esd poppet valve to decrease to the point that the valve tripped and the bo valve opened. The source of moisture was most likely from the esd trigger pneumatic supply unit. Accumulated moisture was discovered in the esd air storage tank. Eventually, the cs air dryer allowed the dew point of the compressed air to increase. When the ambient air temperature dropped below the dew point of the compressed air, the water vapor condensed in the esd storage tank and the trigger air piping. Recommendations: 1) compressor stations that use a pneumatic system in their esd systems are recommended to consider installing a dew point analyzer at the outlet of the air dryer to monitor performance and provide an alarm output to the cs controller so appropriate actions can be taken. 2) consider adding in columbia's work management system (wms) a preventive maintenance (pm) task to the esd system to perform an annual purge to the pneumatic system and verify if presence of moisture was identified. Also, consider the addition of another pm to the critical shafer actuator installations to inspect routinely the seals for evidence of deterioration. Site specific: per the provided recommendations in the rca report, a dew point analyzer with continuous feedback and alarm output was installed with the addition of the appropriate pms in the wms.
Detailed record list
Report Received Date
2015-12-20 00:00:00
Iyear
2015
Report Number
20150151
Supplemental Number
17189
Report Type
Supplemental Final
Operator Id
2616
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
2015-11-23 06:34:00
Location Latitude
38.8782
Location Longitude
-81.690525
Nrc Rpt Num
1134088
Nrc Rpt Datetime
2015-11-23 07:47:00
Commodity Released Type
Natural Gas
Unintentional Release
10474
Intentional Release
0
Accompanying Liquid
0
Fatality Ind
No
Fatal
0
Injury Ind
No
Injure
0
Shutdown Due Accident Ind
No
Shutdown Explain
Affected Line Sement Was Isolated
Ignite Ind
No
Explode Ind
No
Num Pub Evacuated
0
Incident Identified Datetime
2015-11-23 06:34:00
On Site Datetime
2015-11-23 06:55:00
On Off Shore
Onshore
Onshore State Abbreviation
Wv
Onshore Postal Code
25275
Onshore City Name
Sandyville
Onshore County Name
Jackson County
Designated Location
Milepost
Designated Name
C36-30
Pipe Fac Name
Ripley Compressor Station
Segment Name
Blow-Off Valve
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
1999
Material Involved
Carbon Steel
Release Type
Other
Release Type Details
Unintended Release Of Natural Gas Due To Accumulated Moisture In Esd Pneumatic System
Class Location Type
Class 2 Location
Could Be Hca
No
Pir Radius
244
Heat Damage Ind
No
Non Heat Damage Ind
No
Hca Fatalities Ind
No
Est Cost Oper Paid
0
Est Cost Unintentional Release
19691
Est Cost Intentional Release
0
Est Cost Prop Damage
0
Est Cost Emergency
0
Est Cost Other
0
Est Cost Other Details
There Were No Other Associated Costs
Prpty
19691
Accident Psig
875
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
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
Root cause analysis investigation indicated that gas control personnel did not perform any activities or had any other involvements contributing to initiate this incident,
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
Appurtenance Failure
Additional Valve Ind
Yes
Eq Additional Other Ind
Yes
Eq Additional Other Details
Bo Valve Activation Due To Accumulated Moisture
Preparer Name
G***** H*****
Preparer Title
Engineer
Preparer Email
G******@c**.com
Preparer Telephone
(304) 357-3728
Authorizer Name
J**** M* P****
Authorizer Title
Director
Authorizer Telephone
(713)386-3404
Authorizer Email
J*****@c**.com
Narrative
On november 23, 2015, a columbia gas transmission, llc (columbia) facility was subject to an event that involved an unintended activation of an 8-in blow-off (bo) valve. This bo valve is located in ripley compressor station (cs) yard. Ripley cs is a transmission facility located near the town of sandyville, jackson county, west virginia is owned, operated and maintained by columbia. Columbia operations personnel responded to this event and isolated the bo valve with its respective pipeline preventing additional unintended release of natural gas (material) into atmosphere. There was no presence of fire, explosion or evacuations in lieu of the material release. The initial assessment indicated that presence of accumulated moisture played a contributing factor in the chain of events that led to this incident. The emergency shutdown (esd) system trigger pneumatic pressure on that actuator bled down below the required pressure to hold the valve closed. The esd pneumatic pressure to all other esd valves remained at its full system pressure. An accumulation of approximately 2 gallons of accumulated moisture was drained from the esd trigger pneumatic supply tank, that is located directly downstream of the facility's air dryer system. A vendor technician was on site the following day of the incident where a full assessment to the air dryer followed. The vendor's technician identified that the air dryer system's automatic control system was locked-up. A manual switching operation was performed to enable the full operation of the two air dryer system towers. The root cause analysis (rca) report concluded that moisture collected in the esd trigger pneumatic tubing froze which allowed the pressure on the esd poppet valve to decrease to the point that the valve tripped and the bo valve opened. The source of moisture was most likely from the esd trigger pneumatic supply unit. Accumulated moisture was discovered in the esd air storage tank. Eventually, the cs air dryer allowed the dew point of the compressed air to increase. When the ambient air temperature dropped below the dew point of the compressed air, the water vapor condensed in the esd storage tank and the trigger air piping. Recommendations: 1) compressor stations that use a pneumatic system in their esd systems are recommended to consider installing a dew point analyzer at the outlet of the air dryer to monitor performance and provide an alarm output to the cs controller so appropriate actions can be taken. 2) consider adding in columbia's work management system (wms) a preventive maintenance (pm) task to the esd system to perform an annual purge to the pneumatic system and verify if presence of moisture was identified. Also, consider the addition of another pm to the critical shafer actuator installations to inspect routinely the seals for evidence of deterioration. Site specific: per the provided recommendations in the rca report, a dew point analyzer with continuous feedback and alarm output was installed with the addition of the appropriate pms in the wms.
| Report Received Date | 2015-12-20 00:00:00 |
|---|---|
| Iyear | 2015 |
| Report Number | 20150151 |
| Supplemental Number | 17189 |
| 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 | 2015-11-23 06:34:00 |
| Location Latitude | 38.8782 Google Maps OpenStreetMap |
| Location Longitude | -81.690525 Google Maps OpenStreetMap |
| Nrc Rpt Num | 1134088 NRC Report How to search |
| Nrc Rpt Datetime | 2015-11-23 07:47:00 |
| Commodity Released Type | Natural Gas |
| Unintentional Release | 10474 |
| Intentional Release | 0 |
| Accompanying Liquid | 0 |
| Fatality Ind | No |
| Fatal | 0 |
| Injury Ind | No |
| Injure | 0 |
| Shutdown Due Accident Ind | No |
| Shutdown Explain | Affected Line Sement Was Isolated |
| Ignite Ind | No |
| Explode Ind | No |
| Num Pub Evacuated | 0 |
| Incident Identified Datetime | 2015-11-23 06:34:00 |
| On Site Datetime | 2015-11-23 06:55:00 |
| On Off Shore | Onshore |
| Onshore State Abbreviation | Wv |
| Onshore Postal Code | 25275 |
| Onshore City Name | Sandyville |
| Onshore County Name | Jackson County |
| Designated Location | Milepost |
| Designated Name | C36-30 |
| Pipe Fac Name | Ripley Compressor Station |
| Segment Name | Blow-Off Valve |
| 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 | 1999 |
| Material Involved | Carbon Steel |
| Release Type | Other |
| Release Type Details | Unintended Release Of Natural Gas Due To Accumulated Moisture In Esd Pneumatic System |
| Class Location Type | Class 2 Location |
| Could Be Hca | No |
| Pir Radius | 244 |
| Heat Damage Ind | No |
| Non Heat Damage Ind | No |
| Hca Fatalities Ind | No |
| Est Cost Oper Paid | 0 |
| Est Cost Unintentional Release | 19691 |
| Est Cost Intentional Release | 0 |
| Est Cost Prop Damage | 0 |
| Est Cost Emergency | 0 |
| Est Cost Other | 0 |
| Est Cost Other Details | There Were No Other Associated Costs |
| Prpty | 19691 |
| Accident Psig | 875 |
| 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 | 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 | Root cause analysis investigation indicated that gas control personnel did not perform any activities or had any other involvements contributing to initiate this incident, |
| 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 | Appurtenance Failure |
| Additional Valve Ind | Yes |
| Eq Additional Other Ind | Yes |
| Eq Additional Other Details | Bo Valve Activation Due To Accumulated Moisture |
| Preparer Name | G***** H***** |
| Preparer Title | Engineer |
| Preparer Email | G******@c**.com |
| Preparer Telephone | (304) 357-3728 |
| Authorizer Name | J**** M* P**** |
| Authorizer Title | Director |
| Authorizer Telephone | (713)386-3404 |
| Authorizer Email | J*****@c**.com |
| Narrative | On november 23, 2015, a columbia gas transmission, llc (columbia) facility was subject to an event that involved an unintended activation of an 8-in blow-off (bo) valve. This bo valve is located in ripley compressor station (cs) yard. Ripley cs is a transmission facility located near the town of sandyville, jackson county, west virginia is owned, operated and maintained by columbia. Columbia operations personnel responded to this event and isolated the bo valve with its respective pipeline preventing additional unintended release of natural gas (material) into atmosphere. There was no presence of fire, explosion or evacuations in lieu of the material release. The initial assessment indicated that presence of accumulated moisture played a contributing factor in the chain of events that led to this incident. The emergency shutdown (esd) system trigger pneumatic pressure on that actuator bled down below the required pressure to hold the valve closed. The esd pneumatic pressure to all other esd valves remained at its full system pressure. An accumulation of approximately 2 gallons of accumulated moisture was drained from the esd trigger pneumatic supply tank, that is located directly downstream of the facility's air dryer system. A vendor technician was on site the following day of the incident where a full assessment to the air dryer followed. The vendor's technician identified that the air dryer system's automatic control system was locked-up. A manual switching operation was performed to enable the full operation of the two air dryer system towers. The root cause analysis (rca) report concluded that moisture collected in the esd trigger pneumatic tubing froze which allowed the pressure on the esd poppet valve to decrease to the point that the valve tripped and the bo valve opened. The source of moisture was most likely from the esd trigger pneumatic supply unit. Accumulated moisture was discovered in the esd air storage tank. Eventually, the cs air dryer allowed the dew point of the compressed air to increase. When the ambient air temperature dropped below the dew point of the compressed air, the water vapor condensed in the esd storage tank and the trigger air piping. Recommendations: 1) compressor stations that use a pneumatic system in their esd systems are recommended to consider installing a dew point analyzer at the outlet of the air dryer to monitor performance and provide an alarm output to the cs controller so appropriate actions can be taken. 2) consider adding in columbia's work management system (wms) a preventive maintenance (pm) task to the esd system to perform an annual purge to the pneumatic system and verify if presence of moisture was identified. Also, consider the addition of another pm to the critical shafer actuator installations to inspect routinely the seals for evidence of deterioration. Site specific: per the provided recommendations in the rca report, a dew point analyzer with continuous feedback and alarm output was installed with the addition of the appropriate pms in the wms. |
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