GD incident on 2019-11-18 — MT

Operator
Montana - Dakota Utilities Co
Cause
Other Outside Force Damage
Commodity
Natural Gas
Program
GD
Damage and Injuries
0 fatalities 2 injuries
Property damage (nominal)
$15,000
Incident datetime
2019-11-18 00:39
Report number
Location
MT, YELLOWSTONE
Narrative
At 00:39 on november 18, 2019, emergency responders contacted montana-dakota utilities call center to report a house fire with possible explosion. A local service technician was dispatched immediately upon notification. Upon arrival the service tech made the area safe and started to assess the scene. It was confirmed that an explosion had occurred at a private residence and two occupants were taken to the hospital. Verbal communication from the billings fire department indicated two occupants were taken to the billings hospital and then flown to a hospital in denver. A leak investigation outside the residence was completed, gas was indicated at the riser of the residence with highest concentration of gas at the intersection of two 1982 vintage 1 1/4" plastic mains across the alley. The mains feeding the tee were isolated, securing the leak at 05:50 on november 18, 2019. The main was excavated and a crack was discovered at the interface of the pipe at a socket tee connecting the mains. Factors that caused the gas to be controlled at 5:50 were the time required to complete a leak investigation to ensure the safety of the surrounding structures, pinpoint the suspected source of the gas, get emergency locates completed, excavate the location of the highest concentration of gas to ensure the location of leak, and excavate two locations for shut off of the gas due to the area being served from two locations. Upon excavation, the pipe at the tee location, had a deflection from the main line which would be inconsistent with the standard installation of the pipe. This deflection may have been caused from improper support during third party excavation or improper backfill methods post third party excavation that occurred sometime after montana-dakota's initial installation of the pipe. Further indication that outside forces caused the crack include backfill material surrounding the pipe and tee that appeared to be foreign from native materials that would have been used at time of initial installation. 4/8/2021 - the pe pipe material was revised to correct from pe 2406 to pe 2306. 4/19/2021 - the numbers for gas released (pg. 1 items 7) and gas consumed (pg. 2 item 21c) are not known. Phmsa form f 7100.1 requires a numerical entry even though an estimated value is unable to be determined. 5/3/2021 - added the pipe manufacturer and updated nrc report numbers. Volume of gas unintentionally released calculated using and estimated opening of 0.05 square inches and a pressure of 55 psig. For purposes of providing and illustrative calculation of gas loss, an estimated time of 3 months was utilized.
Detailed record list
Occurred At
2019-11-18 00:39:00
Year
2019
Report Received Date
2019-12-17 00:00:00
Iyear
2019.0
Report Number
20190145.0
Supplemental Number
35237.0
Report Type
Supplemental Final
Operator Id
Name
Montana - Dakota Utilities Co
Operator Street Address
400 North Fourth Street
Operator City Name
Bismarck
Operator State Abbreviation
ND
Operator Postal Code
58501
Local Datetime
2019-11-18 00:39:00
Time Zone
Mountain
Daylight Savings Ind
No
Location Street Address
814 S 28th Street
Location City Name
Billings
Location County Name
Yellowstone
Location State Abbreviation
MT
Location Postal Code
59101
Location Latitude
Location Longitude
Flow Cont Squeeze Off Ind
Yes
Nrc Rpt Datetime
2019-11-18 02:12:00
Nrc Rpt Num
Additional Nrc Report Numbers
1264344
Commodity Released Type
Natural Gas
Unintentional Release
299.38
Intentional Release
0.0
Fatality Ind
No
Fatal
0
Injury Ind
Yes
Num Emp Injuries
0
Num Contr Injuries
0
Num Er Injuries
0
Num Worker Injuries
0
Num Gp Injuries
2
Injure
2
Ignite Ind
Yes
Ignite Datetime
2019-11-18 00:39:00
How Extinguished
Local/state/federal Emergency Responder
Gas Consumed By Fire In Mcf
1
Explode Ind
Yes
Num Pub Evacuated
4.0
Incident Identified Datetime
2019-11-18 00:39:00
On Site Datetime
2019-11-18 01:13:00
Federal
No
Location Type
Utility Right-Of-Way / Easement
Incident Area Type
Underground
Incident Area Subtype
Under Soil
Depth Of Cover
32.0
Other Underground Facilities
No
Crossing
No
Pipe Facility Type
Investor Owned
System Part Involved
Main
Installation Year
1982.0
Pipe Diameter
1.25
Pipe Specification
Unknown
Pipe Manufacturer
Dupont Aldyal-A
Material Involved
Plastic
Plastic Type
Polyethylene (Pe)
Plastic Sdr
10
Material Pe Pipe Code
2306
Release Type
Leak
Leak Type
Crack
Class Location Type
Class 3 Location
Est Cost Oper Paid
100000.0
Est Cost Prop Damage
15000.0
Est Cost Emergency
2500.0
Est Cost Other
0.0
Gas Cost In Mcf
3.71
Est Cost Unintentional Release
1111.0
Est Cost Intentional Release
0.0
Prpty
118611.0
Commercial Affected
0.0
Industrial Affected
0.0
Residences Affected
4.0
Num Persons Hosp Not Ovnght
0.0
Num Injured Treated By Emt
0.0
Num Resident Building Affctd
4.0
Num Business Building Affctd
0.0
Accident Psig
55.0
Normal Psig
55.0
Mop Psig
60.0
Mop Cfr Section
192.619(A)(2)
Maop Established Date
1982-06-24 00:00:00
Accident Pressure
Pressure Did Not Exceed Maop
Gas Odorized System Type
Odorized By Others
Gas Odorized Level
20
Scada In Place Ind
No
Accident Identifier
Notification From Emergency Responder
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
Other Outside Force Damage
Cause Details
Other Outside Force Damage
Outside Force Type
Other Outside Force Damage
Osf Other Details
Evidence Of Foreign Backfill.
Preparer Name
D**** L H***
Preparer Title
Mgr Policy And Procedure
Preparer Email
D*********@m**.com
Preparer Telephone
7015162749
Local Contact Name
D***** B***
Local Contact Email
D**********@m**.com
Local Contact Telephone
4068964210
Authorizer Name
D**** L* H***
Authorizer Title
Mgr Policy And Procedure
Authorizer Telephone
7015162749
Authorizer Email
D*********@m**.com
Narrative
At 00:39 on november 18, 2019, emergency responders contacted montana-dakota utilities call center to report a house fire with possible explosion. A local service technician was dispatched immediately upon notification. Upon arrival the service tech made the area safe and started to assess the scene. It was confirmed that an explosion had occurred at a private residence and two occupants were taken to the hospital. Verbal communication from the billings fire department indicated two occupants were taken to the billings hospital and then flown to a hospital in denver. A leak investigation outside the residence was completed, gas was indicated at the riser of the residence with highest concentration of gas at the intersection of two 1982 vintage 1 1/4" plastic mains across the alley. The mains feeding the tee were isolated, securing the leak at 05:50 on november 18, 2019. The main was excavated and a crack was discovered at the interface of the pipe at a socket tee connecting the mains. Factors that caused the gas to be controlled at 5:50 were the time required to complete a leak investigation to ensure the safety of the surrounding structures, pinpoint the suspected source of the gas, get emergency locates completed, excavate the location of the highest concentration of gas to ensure the location of leak, and excavate two locations for shut off of the gas due to the area being served from two locations. Upon excavation, the pipe at the tee location, had a deflection from the main line which would be inconsistent with the standard installation of the pipe. This deflection may have been caused from improper support during third party excavation or improper backfill methods post third party excavation that occurred sometime after montana-dakota's initial installation of the pipe. Further indication that outside forces caused the crack include backfill material surrounding the pipe and tee that appeared to be foreign from native materials that would have been used at time of initial installation. 4/8/2021 - the pe pipe material was revised to correct from pe 2406 to pe 2306. 4/19/2021 - the numbers for gas released (pg. 1 items 7) and gas consumed (pg. 2 item 21c) are not known. Phmsa form f 7100.1 requires a numerical entry even though an estimated value is unable to be determined. 5/3/2021 - added the pipe manufacturer and updated nrc report numbers. Volume of gas unintentionally released calculated using and estimated opening of 0.05 square inches and a pressure of 55 psig. For purposes of providing and illustrative calculation of gas loss, an estimated time of 3 months was utilized.
Occurred At 2019-11-18 00:39:00
Year 2019
Report Received Date 2019-12-17 00:00:00
Iyear 2019.0
Report Number 20190145.0
Supplemental Number 35237.0
Report Type Supplemental Final
Operator Id 12684 PHMSA Enforcement
Name Montana - Dakota Utilities Co
Operator Street Address 400 North Fourth Street
Operator City Name Bismarck
Operator State Abbreviation ND
Operator Postal Code 58501
Local Datetime 2019-11-18 00:39:00
Time Zone Mountain
Daylight Savings Ind No
Location Street Address 814 S 28th Street
Location City Name Billings
Location County Name Yellowstone
Location State Abbreviation MT
Location Postal Code 59101
Location Latitude 45.77285 Google Maps OpenStreetMap
Location Longitude -108.49718 Google Maps OpenStreetMap
Flow Cont Squeeze Off Ind Yes
Nrc Rpt Datetime 2019-11-18 02:12:00
Nrc Rpt Num 1264173 NRC Report How to search
Additional Nrc Report Numbers 1264344
Commodity Released Type Natural Gas
Unintentional Release 299.38
Intentional Release 0.0
Fatality Ind No
Fatal 0
Injury Ind Yes
Num Emp Injuries 0
Num Contr Injuries 0
Num Er Injuries 0
Num Worker Injuries 0
Num Gp Injuries 2
Injure 2
Ignite Ind Yes
Ignite Datetime 2019-11-18 00:39:00
How Extinguished Local/state/federal Emergency Responder
Gas Consumed By Fire In Mcf 1
Explode Ind Yes
Num Pub Evacuated 4.0
Incident Identified Datetime 2019-11-18 00:39:00
On Site Datetime 2019-11-18 01:13:00
Federal No
Location Type Utility Right-Of-Way / Easement
Incident Area Type Underground
Incident Area Subtype Under Soil
Depth Of Cover 32.0
Other Underground Facilities No
Crossing No
Pipe Facility Type Investor Owned
System Part Involved Main
Installation Year 1982.0
Pipe Diameter 1.25
Pipe Specification Unknown
Pipe Manufacturer Dupont Aldyal-A
Material Involved Plastic
Plastic Type Polyethylene (Pe)
Plastic Sdr 10
Material Pe Pipe Code 2306
Release Type Leak
Leak Type Crack
Class Location Type Class 3 Location
Est Cost Oper Paid 100000.0
Est Cost Prop Damage 15000.0
Est Cost Emergency 2500.0
Est Cost Other 0.0
Gas Cost In Mcf 3.71
Est Cost Unintentional Release 1111.0
Est Cost Intentional Release 0.0
Prpty 118611.0
Commercial Affected 0.0
Industrial Affected 0.0
Residences Affected 4.0
Num Persons Hosp Not Ovnght 0.0
Num Injured Treated By Emt 0.0
Num Resident Building Affctd 4.0
Num Business Building Affctd 0.0
Accident Psig 55.0
Normal Psig 55.0
Mop Psig 60.0
Mop Cfr Section 192.619(A)(2) View CFR 49 §192
Maop Established Date 1982-06-24 00:00:00
Accident Pressure Pressure Did Not Exceed Maop
Gas Odorized System Type Odorized By Others
Gas Odorized Level 20
Scada In Place Ind No
Accident Identifier Notification From Emergency Responder
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 Other Outside Force Damage
Cause Details Other Outside Force Damage
Outside Force Type Other Outside Force Damage
Osf Other Details Evidence Of Foreign Backfill.
Preparer Name D**** L H***
Preparer Title Mgr Policy And Procedure
Preparer Email D*********@m**.com
Preparer Telephone 7015162749
Local Contact Name D***** B***
Local Contact Email D**********@m**.com
Local Contact Telephone 4068964210
Authorizer Name D**** L* H***
Authorizer Title Mgr Policy And Procedure
Authorizer Telephone 7015162749
Authorizer Email D*********@m**.com
Narrative At 00:39 on november 18, 2019, emergency responders contacted montana-dakota utilities call center to report a house fire with possible explosion. A local service technician was dispatched immediately upon notification. Upon arrival the service tech made the area safe and started to assess the scene. It was confirmed that an explosion had occurred at a private residence and two occupants were taken to the hospital. Verbal communication from the billings fire department indicated two occupants were taken to the billings hospital and then flown to a hospital in denver. A leak investigation outside the residence was completed, gas was indicated at the riser of the residence with highest concentration of gas at the intersection of two 1982 vintage 1 1/4" plastic mains across the alley. The mains feeding the tee were isolated, securing the leak at 05:50 on november 18, 2019. The main was excavated and a crack was discovered at the interface of the pipe at a socket tee connecting the mains. Factors that caused the gas to be controlled at 5:50 were the time required to complete a leak investigation to ensure the safety of the surrounding structures, pinpoint the suspected source of the gas, get emergency locates completed, excavate the location of the highest concentration of gas to ensure the location of leak, and excavate two locations for shut off of the gas due to the area being served from two locations. Upon excavation, the pipe at the tee location, had a deflection from the main line which would be inconsistent with the standard installation of the pipe. This deflection may have been caused from improper support during third party excavation or improper backfill methods post third party excavation that occurred sometime after montana-dakota's initial installation of the pipe. Further indication that outside forces caused the crack include backfill material surrounding the pipe and tee that appeared to be foreign from native materials that would have been used at time of initial installation. 4/8/2021 - the pe pipe material was revised to correct from pe 2406 to pe 2306. 4/19/2021 - the numbers for gas released (pg. 1 items 7) and gas consumed (pg. 2 item 21c) are not known. Phmsa form f 7100.1 requires a numerical entry even though an estimated value is unable to be determined. 5/3/2021 - added the pipe manufacturer and updated nrc report numbers. Volume of gas unintentionally released calculated using and estimated opening of 0.05 square inches and a pressure of 55 psig. For purposes of providing and illustrative calculation of gas loss, an estimated time of 3 months was utilized.

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