Incident details
Operator, cause, commodity and consequences with raw source fields.
GTG incident on 2015-01-16 — TX
Operator
Southern Natural Gas Co
Cause
Equipment Failure
Commodity
Natural Gas
Program
GTG
Damage and Injuries
0 fatalities
0 injuries
Property damage (nominal)
$1,500
Incident datetime
2015-01-16 17:50
Report number
Location
TX
Narrative
The master fuel gas line at the pearl river compressor station supplies fuel gas to two (2) general electric turbines, an emergency electric power generator, and domestic heat for two (2) station buildings. On january 16, 2015, a local resident reported the sound of gas at the station to southern natural gas pipeline company, llc (sng). Sng gas control responded by dispatching a local sng field technician and he immediately isolated the fuel gas meter run to stop the flow of gas since he observed the relief valve on the first cut of the master fuel run repeatedly activating and resetting at the designated set-points. It should be noted that the station compression was off-line during the event. The responding field technician observed ice build-up on the first-cut, regulator sensing line which caused the regulator to malfunction and the relief valve to actuate. The estimated gas volume released, using meter station flow data, was 8,151 mscf over a 23 hour period from 20:15 hours local time on january 15, 2015 to 19:05 hours local time on january 16, 2015 when sng personnel isolated the fuel meter station. The results of the investigation by sng, completed on january 30, 2015, showed that although a fuel gas heater was installed to heat fuel gas for the compressor station, when the station turbines are offline, the resulting low fuel gas flow (for domestic purposes only) can enable the fuel temperature to drop, especially on cold days, before the gas reaches the master fuel meter. Sng concluded that during extended periods of below-freezing temperatures, with low flow, the fuel temperature can drop and causes ice build-up on the regulator pilot sensing line. Sng will complete the following corrective actions to minimize the effects of freezing on the regulator sensing lines and increase situational awareness of gas release from opp on the fuel gas system: 1) installation of catalytic heaters on pilot regulator sensing lines to prevent ice build-up during conditions of low gas flow and low ambient temperatures. 2) installation of additional pressure transmitter to detect flow through the master fuel meter relieve valve and generate a system alarm when the pressure approaches the relief valve set point. This will prompt a call-out to station personnel.
Detailed record list
Report Received Date
2015-02-12 00:00:00
Iyear
2015
Report Number
20150020
Supplemental Number
16677
Report Type
Supplemental Final
Operator Id
18516
Name
Southern Natural Gas Co
Operator Street Address
1001 Louisiana St, Ste 1000 Suite 1000
Operator City Name
Houston
Operator State Abbreviation
TX
Operator Postal Code
77002
Local Datetime
2015-01-16 19:05:00
Location Latitude
31.326623
Location Longitude
-90.044664
Nrc Rpt Num
1105861
Nrc Rpt Datetime
2015-01-16 20:22:00
Commodity Released Type
Natural Gas
Unintentional Release
8151
Intentional Release
0
Accompanying Liquid
0
Fatality Ind
No
Fatal
0
Injury Ind
No
Injure
0
Shutdown Due Accident Ind
Yes
Shutdown Datetime
2015-01-16 19:05:00
Restart Datetime
2015-01-17 14:00:00
Ignite Ind
No
Explode Ind
No
Num Pub Evacuated
0
Incident Identified Datetime
2015-01-16 17:50:00
On Site Datetime
2015-01-16 19:05:00
On Off Shore
Onshore
Onshore State Abbreviation
Ms
Onshore Postal Code
39478
Onshore City Name
Not Within A Municipality
Onshore County Name
Walthall County
Designated Location
Milepost
Designated Name
Mp: 36.355
Pipe Fac Name
Pearl River Meter Station
Segment Name
Pearl River Compressor Station 5130
Federal
No
Location Type
Pipeline Right-Of-Way
Incident Area Type
Aboveground
Incident Area Subtype
Typical Aboveground Facility Piping Or Appurtenance
Crossing
No
Pipe Facility Type
Interstate
System Part Involved
Onshore Regulator/metering Station Equipment And Piping
Item Involved
Regulator/control Valve
Installation Year
2014
Material Involved
Carbon Steel
Release Type
Other
Release Type Details
Master Fuel Regulator Began To Leak Causing The Relief Valve To Activate And Reset.
Class Location Type
Class 1 Location
Could Be Hca
No
Pir Radius
614
Heat Damage Ind
No
Non Heat Damage Ind
No
Hca Fatalities Ind
No
Est Cost Oper Paid
0
Est Cost Unintentional Release
25350
Est Cost Intentional Release
0
Est Cost Prop Damage
1500
Est Cost Emergency
0
Est Cost Other
0
Prpty
26850
Accident Psig
540
Mop Psig
600
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
Yes
Accident Identifier
Notification From Public
Investigation Status
No, the facility was not monitored by a controller(s) at the time of the incident
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
Pressure Regulator Ind
Yes
Eq Additional Other Ind
Yes
Eq Additional Other Details
Ice Build-Up On Regulator Pilot Sensing Line.
Preparer Name
S****** R* D****
Preparer Title
Engineer
Preparer Email
S************@k***********.com
Preparer Telephone
(719) 329-5633
Authorizer Name
R*** G*****
Authorizer Title
Director Of Engineering Codes And Standards
Authorizer Telephone
(713) 420-5433
Authorizer Email
R**********@k***********.com
Narrative
The master fuel gas line at the pearl river compressor station supplies fuel gas to two (2) general electric turbines, an emergency electric power generator, and domestic heat for two (2) station buildings. On january 16, 2015, a local resident reported the sound of gas at the station to southern natural gas pipeline company, llc (sng). Sng gas control responded by dispatching a local sng field technician and he immediately isolated the fuel gas meter run to stop the flow of gas since he observed the relief valve on the first cut of the master fuel run repeatedly activating and resetting at the designated set-points. It should be noted that the station compression was off-line during the event. The responding field technician observed ice build-up on the first-cut, regulator sensing line which caused the regulator to malfunction and the relief valve to actuate. The estimated gas volume released, using meter station flow data, was 8,151 mscf over a 23 hour period from 20:15 hours local time on january 15, 2015 to 19:05 hours local time on january 16, 2015 when sng personnel isolated the fuel meter station. The results of the investigation by sng, completed on january 30, 2015, showed that although a fuel gas heater was installed to heat fuel gas for the compressor station, when the station turbines are offline, the resulting low fuel gas flow (for domestic purposes only) can enable the fuel temperature to drop, especially on cold days, before the gas reaches the master fuel meter. Sng concluded that during extended periods of below-freezing temperatures, with low flow, the fuel temperature can drop and causes ice build-up on the regulator pilot sensing line. Sng will complete the following corrective actions to minimize the effects of freezing on the regulator sensing lines and increase situational awareness of gas release from opp on the fuel gas system: 1) installation of catalytic heaters on pilot regulator sensing lines to prevent ice build-up during conditions of low gas flow and low ambient temperatures. 2) installation of additional pressure transmitter to detect flow through the master fuel meter relieve valve and generate a system alarm when the pressure approaches the relief valve set point. This will prompt a call-out to station personnel.
| Report Received Date | 2015-02-12 00:00:00 |
|---|---|
| Iyear | 2015 |
| Report Number | 20150020 |
| Supplemental Number | 16677 |
| Report Type | Supplemental Final |
| Operator Id | 18516 PHMSA Enforcement |
| Name | Southern Natural Gas Co |
| Operator Street Address | 1001 Louisiana St, Ste 1000 Suite 1000 |
| Operator City Name | Houston |
| Operator State Abbreviation | TX |
| Operator Postal Code | 77002 |
| Local Datetime | 2015-01-16 19:05:00 |
| Location Latitude | 31.326623 Google Maps OpenStreetMap |
| Location Longitude | -90.044664 Google Maps OpenStreetMap |
| Nrc Rpt Num | 1105861 NRC Report How to search |
| Nrc Rpt Datetime | 2015-01-16 20:22:00 |
| Commodity Released Type | Natural Gas |
| Unintentional Release | 8151 |
| Intentional Release | 0 |
| Accompanying Liquid | 0 |
| Fatality Ind | No |
| Fatal | 0 |
| Injury Ind | No |
| Injure | 0 |
| Shutdown Due Accident Ind | Yes |
| Shutdown Datetime | 2015-01-16 19:05:00 |
| Restart Datetime | 2015-01-17 14:00:00 |
| Ignite Ind | No |
| Explode Ind | No |
| Num Pub Evacuated | 0 |
| Incident Identified Datetime | 2015-01-16 17:50:00 |
| On Site Datetime | 2015-01-16 19:05:00 |
| On Off Shore | Onshore |
| Onshore State Abbreviation | Ms |
| Onshore Postal Code | 39478 |
| Onshore City Name | Not Within A Municipality |
| Onshore County Name | Walthall County |
| Designated Location | Milepost |
| Designated Name | Mp: 36.355 |
| Pipe Fac Name | Pearl River Meter Station |
| Segment Name | Pearl River Compressor Station 5130 |
| Federal | No |
| Location Type | Pipeline Right-Of-Way |
| Incident Area Type | Aboveground |
| Incident Area Subtype | Typical Aboveground Facility Piping Or Appurtenance |
| Crossing | No |
| Pipe Facility Type | Interstate |
| System Part Involved | Onshore Regulator/metering Station Equipment And Piping |
| Item Involved | Regulator/control Valve |
| Installation Year | 2014 |
| Material Involved | Carbon Steel |
| Release Type | Other |
| Release Type Details | Master Fuel Regulator Began To Leak Causing The Relief Valve To Activate And Reset. |
| Class Location Type | Class 1 Location |
| Could Be Hca | No |
| Pir Radius | 614 |
| Heat Damage Ind | No |
| Non Heat Damage Ind | No |
| Hca Fatalities Ind | No |
| Est Cost Oper Paid | 0 |
| Est Cost Unintentional Release | 25350 |
| Est Cost Intentional Release | 0 |
| Est Cost Prop Damage | 1500 |
| Est Cost Emergency | 0 |
| Est Cost Other | 0 |
| Prpty | 26850 |
| Accident Psig | 540 |
| Mop Psig | 600 |
| 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 | Yes |
| Accident Identifier | Notification From Public |
| Investigation Status | No, the facility was not monitored by a controller(s) at the time of the incident |
| 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 |
| Pressure Regulator Ind | Yes |
| Eq Additional Other Ind | Yes |
| Eq Additional Other Details | Ice Build-Up On Regulator Pilot Sensing Line. |
| Preparer Name | S****** R* D**** |
| Preparer Title | Engineer |
| Preparer Email | S************@k***********.com |
| Preparer Telephone | (719) 329-5633 |
| Authorizer Name | R*** G***** |
| Authorizer Title | Director Of Engineering Codes And Standards |
| Authorizer Telephone | (713) 420-5433 |
| Authorizer Email | R**********@k***********.com |
| Narrative | The master fuel gas line at the pearl river compressor station supplies fuel gas to two (2) general electric turbines, an emergency electric power generator, and domestic heat for two (2) station buildings. On january 16, 2015, a local resident reported the sound of gas at the station to southern natural gas pipeline company, llc (sng). Sng gas control responded by dispatching a local sng field technician and he immediately isolated the fuel gas meter run to stop the flow of gas since he observed the relief valve on the first cut of the master fuel run repeatedly activating and resetting at the designated set-points. It should be noted that the station compression was off-line during the event. The responding field technician observed ice build-up on the first-cut, regulator sensing line which caused the regulator to malfunction and the relief valve to actuate. The estimated gas volume released, using meter station flow data, was 8,151 mscf over a 23 hour period from 20:15 hours local time on january 15, 2015 to 19:05 hours local time on january 16, 2015 when sng personnel isolated the fuel meter station. The results of the investigation by sng, completed on january 30, 2015, showed that although a fuel gas heater was installed to heat fuel gas for the compressor station, when the station turbines are offline, the resulting low fuel gas flow (for domestic purposes only) can enable the fuel temperature to drop, especially on cold days, before the gas reaches the master fuel meter. Sng concluded that during extended periods of below-freezing temperatures, with low flow, the fuel temperature can drop and causes ice build-up on the regulator pilot sensing line. Sng will complete the following corrective actions to minimize the effects of freezing on the regulator sensing lines and increase situational awareness of gas release from opp on the fuel gas system: 1) installation of catalytic heaters on pilot regulator sensing lines to prevent ice build-up during conditions of low gas flow and low ambient temperatures. 2) installation of additional pressure transmitter to detect flow through the master fuel meter relieve valve and generate a system alarm when the pressure approaches the relief valve set point. This will prompt a call-out to station personnel. |
External Resources
PHMSA pipeline safety insights.
Product
Features
Company
All rights reserved. Copyright © by ClearPHMSA