GTG incident on 2015-01-07 — CA

Operator
Pacific Gas & Electric Co
Cause
Equipment Failure
Commodity
Natural Gas
Program
GTG
Damage and Injuries
0 fatalities 0 injuries
Property damage (nominal)
$5,000
Incident datetime
2015-01-07 17:04
Report number
Location
CA
Narrative
On january 7, 2015 at 1704 hours in arvin, an 8-inch pressure relief valve (at pressure limiting station,4-pls off of transmission line l-300b) opened prior to reaching its set point of 749 psig resulting in an unintentional release of natural gas to the atmosphere. The pressure in l-300b at the time the relief valve operated was 720 psig. The incident was identified on pg&e's scada system. In response, pg&e gas control remotely lowered the pressure in l-300b by lowering the setpoint of the upstream regulator to 675 psig, which allowed the pressure relief valve to close at 1710 hours. Pg&e personnel arrived on scene at 1745 hours and the valve's set point of 749 psig was tested and verified. Pg&e contracted a third party engineering firm to perform a root cause analysis and provide recommendations to the station. Pg&e implemented several modifications and is currently in the design phase to rebuild pls-4. Pg&e inspects and calibrates pressure relief valves (prv) as part of pg&e's routine maintenance program, which is designed to ensure the reliable operation of this equipment at pg&e's pressure limiting stations. No customers lost gas service during the incident. Pressure in l-300b did not exceed the maop of 757 psig. There were no injuries, no fatalities and no media observed on scene during the incident. On january 9, 2015, it was estimated that the volume of gas released exceeded 3 million cubic feet (mmcf), therefore the incident was reported to the national response center and the cpuc. (please note that the responses to part e, questions 5a, 5b, and 5c of this PHMSA 7100 report are merely placeholders and do not apply. Pg&e gas control remotely lowered the pressure in l-300b by lowering the setpoint of the upstream regulator, which allowed the pressure relief valve to close. The PHMSA 7100 report form does not allow these fields to be left blank.)
Detailed record list
Report Received Date
2015-02-06 00:00:00
Iyear
2015
Report Number
20150015
Supplemental Number
16902
Report Type
Supplemental Final
Operator Id
Name
Pacific Gas & Electric Co
Operator Street Address
6121 Bollinger Canyon Rd.
Operator City Name
San Ramon
Operator State Abbreviation
CA
Operator Postal Code
94583
Local Datetime
2015-01-07 17:04:00
Location Latitude
Location Longitude
Nrc Rpt Num
Nrc Rpt Datetime
2015-01-09 00:00:00
Commodity Released Type
Natural Gas
Unintentional Release
4250
Intentional Release
0
Accompanying Liquid
0
Fatality Ind
No
Fatal
0
Injury Ind
No
Injure
0
Shutdown Due Accident Ind
No
Shutdown Explain
Closed Valve By Remotely Lowering Pressure Of Upstream Regulator Setpoint
Ignite Ind
No
Explode Ind
No
Num Pub Evacuated
0
Incident Identified Datetime
2015-01-07 17:04:00
On Site Datetime
2015-01-07 17:45:00
On Off Shore
Onshore
Onshore State Abbreviation
Ca
Onshore Postal Code
93203
Onshore City Name
Arvin
Onshore County Name
Kern County
Designated Location
Milepost
Designated Name
4-Pls
Pipe Fac Name
L-300b
Segment Name
Mp 256.64
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
Intrastate
System Part Involved
Onshore Pipeline, Including Valve Sites
Item Involved
Valve
Valve Type
Relief Valve
Installation Year
2014
Material Involved
Carbon Steel
Release Type
Other
Release Type Details
Pressure Relief Valve Unintentionally Vented Natural Gas
Class Location Type
Class 1 Location
Could Be Hca
No
Pir Radius
650
Heat Damage Ind
No
Non Heat Damage Ind
No
Hca Fatalities Ind
No
Est Cost Oper Paid
0
Est Cost Unintentional Release
14000
Est Cost Intentional Release
0
Est Cost Prop Damage
5000
Est Cost Emergency
0
Est Cost Other
0
Prpty
19000
Accident Psig
720
Mop Psig
757
Mop Cfr Section
192.619(A)(1)
Accident Pressure
Pressure Did Not Exceed Maop
Pressure Restriction Ind
No
Upstream Valve Type Ind
Remotely Controlled
Downstream Valve Type Ind
Remotely Controlled
Internal Inspection Ind
No
Unsuitable Mainline Ind
Yes
Other Inspection Ind
Yes
Internal Inspection Details
A Pig Launcher Is Installed At Pls-4, Which Allows Inspection On L-300b Between Mp 256.65-298.96 (Pls-4 To Pls-5). However, The Section Of L-300b South Of Pls-4 Is Not Currently Piggable Due To Lack Of A Launcher/receiver And Plug Valves Requiring Replacement.
Operation Complications 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
Scada-related equipment operated as intended
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
Relief Valve Ind
Yes
Additional Vibration Ind
Yes
Preparer Name
C***** D****
Preparer Title
Compliance Engineer
Preparer Email
C***@p**.com
Preparer Telephone
925-328-5721
Authorizer Name
L**** D*******
Authorizer Title
Manager Of Gas Operations Regulatory Compliance
Authorizer Telephone
925-328-5756
Authorizer Email
L***@p**.com
Narrative
On january 7, 2015 at 1704 hours in arvin, an 8-inch pressure relief valve (at pressure limiting station,4-pls off of transmission line l-300b) opened prior to reaching its set point of 749 psig resulting in an unintentional release of natural gas to the atmosphere. The pressure in l-300b at the time the relief valve operated was 720 psig. The incident was identified on pg&e's scada system. In response, pg&e gas control remotely lowered the pressure in l-300b by lowering the setpoint of the upstream regulator to 675 psig, which allowed the pressure relief valve to close at 1710 hours. Pg&e personnel arrived on scene at 1745 hours and the valve's set point of 749 psig was tested and verified. Pg&e contracted a third party engineering firm to perform a root cause analysis and provide recommendations to the station. Pg&e implemented several modifications and is currently in the design phase to rebuild pls-4. Pg&e inspects and calibrates pressure relief valves (prv) as part of pg&e's routine maintenance program, which is designed to ensure the reliable operation of this equipment at pg&e's pressure limiting stations. No customers lost gas service during the incident. Pressure in l-300b did not exceed the maop of 757 psig. There were no injuries, no fatalities and no media observed on scene during the incident. On january 9, 2015, it was estimated that the volume of gas released exceeded 3 million cubic feet (mmcf), therefore the incident was reported to the national response center and the cpuc. (please note that the responses to part e, questions 5a, 5b, and 5c of this PHMSA 7100 report are merely placeholders and do not apply. Pg&e gas control remotely lowered the pressure in l-300b by lowering the setpoint of the upstream regulator, which allowed the pressure relief valve to close. The PHMSA 7100 report form does not allow these fields to be left blank.)
Report Received Date 2015-02-06 00:00:00
Iyear 2015
Report Number 20150015
Supplemental Number 16902
Report Type Supplemental Final
Operator Id 15007 PHMSA Enforcement
Name Pacific Gas & Electric Co
Operator Street Address 6121 Bollinger Canyon Rd.
Operator City Name San Ramon
Operator State Abbreviation CA
Operator Postal Code 94583
Local Datetime 2015-01-07 17:04:00
Location Latitude 35.160338 Google Maps OpenStreetMap
Location Longitude -118.80415 Google Maps OpenStreetMap
Nrc Rpt Num 1105278 NRC Report How to search
Nrc Rpt Datetime 2015-01-09 00:00:00
Commodity Released Type Natural Gas
Unintentional Release 4250
Intentional Release 0
Accompanying Liquid 0
Fatality Ind No
Fatal 0
Injury Ind No
Injure 0
Shutdown Due Accident Ind No
Shutdown Explain Closed Valve By Remotely Lowering Pressure Of Upstream Regulator Setpoint
Ignite Ind No
Explode Ind No
Num Pub Evacuated 0
Incident Identified Datetime 2015-01-07 17:04:00
On Site Datetime 2015-01-07 17:45:00
On Off Shore Onshore
Onshore State Abbreviation Ca
Onshore Postal Code 93203
Onshore City Name Arvin
Onshore County Name Kern County
Designated Location Milepost
Designated Name 4-Pls
Pipe Fac Name L-300b
Segment Name Mp 256.64
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 Intrastate
System Part Involved Onshore Pipeline, Including Valve Sites
Item Involved Valve
Valve Type Relief Valve
Installation Year 2014
Material Involved Carbon Steel
Release Type Other
Release Type Details Pressure Relief Valve Unintentionally Vented Natural Gas
Class Location Type Class 1 Location
Could Be Hca No
Pir Radius 650
Heat Damage Ind No
Non Heat Damage Ind No
Hca Fatalities Ind No
Est Cost Oper Paid 0
Est Cost Unintentional Release 14000
Est Cost Intentional Release 0
Est Cost Prop Damage 5000
Est Cost Emergency 0
Est Cost Other 0
Prpty 19000
Accident Psig 720
Mop Psig 757
Mop Cfr Section 192.619(A)(1) View CFR 49 §192
Accident Pressure Pressure Did Not Exceed Maop
Pressure Restriction Ind No
Upstream Valve Type Ind Remotely Controlled
Downstream Valve Type Ind Remotely Controlled
Internal Inspection Ind No
Unsuitable Mainline Ind Yes
Other Inspection Ind Yes
Internal Inspection Details A Pig Launcher Is Installed At Pls-4, Which Allows Inspection On L-300b Between Mp 256.65-298.96 (Pls-4 To Pls-5). However, The Section Of L-300b South Of Pls-4 Is Not Currently Piggable Due To Lack Of A Launcher/receiver And Plug Valves Requiring Replacement.
Operation Complications 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 Scada-related equipment operated as intended
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
Relief Valve Ind Yes
Additional Vibration Ind Yes
Preparer Name C***** D****
Preparer Title Compliance Engineer
Preparer Email C***@p**.com
Preparer Telephone 925-328-5721
Authorizer Name L**** D*******
Authorizer Title Manager Of Gas Operations Regulatory Compliance
Authorizer Telephone 925-328-5756
Authorizer Email L***@p**.com
Narrative On january 7, 2015 at 1704 hours in arvin, an 8-inch pressure relief valve (at pressure limiting station,4-pls off of transmission line l-300b) opened prior to reaching its set point of 749 psig resulting in an unintentional release of natural gas to the atmosphere. The pressure in l-300b at the time the relief valve operated was 720 psig. The incident was identified on pg&e's scada system. In response, pg&e gas control remotely lowered the pressure in l-300b by lowering the setpoint of the upstream regulator to 675 psig, which allowed the pressure relief valve to close at 1710 hours. Pg&e personnel arrived on scene at 1745 hours and the valve's set point of 749 psig was tested and verified. Pg&e contracted a third party engineering firm to perform a root cause analysis and provide recommendations to the station. Pg&e implemented several modifications and is currently in the design phase to rebuild pls-4. Pg&e inspects and calibrates pressure relief valves (prv) as part of pg&e's routine maintenance program, which is designed to ensure the reliable operation of this equipment at pg&e's pressure limiting stations. No customers lost gas service during the incident. Pressure in l-300b did not exceed the maop of 757 psig. There were no injuries, no fatalities and no media observed on scene during the incident. On january 9, 2015, it was estimated that the volume of gas released exceeded 3 million cubic feet (mmcf), therefore the incident was reported to the national response center and the cpuc. (please note that the responses to part e, questions 5a, 5b, and 5c of this PHMSA 7100 report are merely placeholders and do not apply. Pg&e gas control remotely lowered the pressure in l-300b by lowering the setpoint of the upstream regulator, which allowed the pressure relief valve to close. The PHMSA 7100 report form does not allow these fields to be left blank.)

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