Incident details
Operator, cause, commodity and consequences with raw source fields.
GD incident on 2021-09-02 — MA
Operator
Nstar Gas Company
Cause
Corrosion Failure
Commodity
Natural Gas
Program
GD
Damage and Injuries
1 fatality
0 injuries
Property damage (nominal)
$15,874
Incident datetime
2021-09-02 18:35
Report number
Location
MA, MIDDLESEX
Narrative
3.31/25 updated report based on PHMSA request a, b, c, d and g based upon the initial narrative provided by the maynard fire department to eversource, on september 2, 2021 at 16:14, the maynard fire department dispatched resources to 27 park st maynard, ma due to an odor call. The maynard fire department arrived on site at 16:17 to a structure fire. Eversource received a call from the maynard fire department at 16:33 notifying eversource of the subject structure fire. Eversource coordinated with the maynard fire department, massachusetts state fire marshall, and state regulatory agency on site. The situation was made safe through a mainline repair on september 3, 2021. A section of the main with a coupling was secured and delivered to the massachusetts material research facility for 3rd party analysis. Massachusetts material research's investigation of the gas main segment revealed significant corrosion on the entire outer diameter surface of the coupling tube from the soil/dirt service environment. The coupling showed significant wall thinning at isolated locations. At these isolated spots on the coupling, the pits breached through the wall thickness, which created a leak path for the gas to escape from the inside of the gas main. Massachusetts material research found the gas main to be in significantly good condition without any anomalies through the entire length of the pipe segment. Part a.4, a.12 this was the time the company commenced a leak investigation during which gas readings were detected. Part a.21 the company responded yes based upon the initial narrative provided by the maynard fire department and gas readings found in near proximity to the structure fire. Part a.21.A the time the maynard fire department arrived on site to a structure fire. Part a.21.D per "section iii. Conclusion" of the massachusetts fire district fourteen's regional fire investigation team fire origin and cause investigation report, issued to eversource on october 13, 2021, "the most plausible hypothesis is that of fuel gas explosion. It is believed to be an accidental low order fuel gas explosion caused [the] fire." part a.7,a.21.C, d2.F values defaulted to 1 and 0. The amount of gas release is unknown at this time. Part d.2.A the public and non-operator private property damage is currently based on a property assessment provided by the fire department as well as costs associated with landscaping, paving and concrete. Has been updated to reflect building and its contents estimate. Part d.2.B the repair cost includes the repair costs as well as the follow up leak survey costs part e.2 an average operating pressure was obtained prior to the incident. Part e.3.B the main was installed in 1968 pre-code. The date for maop was defaulted to 7/1/1970 as that was when 192.619(c) was established. Part e.5 the drip referenced is a drip odorizer - z9000. Part e.6 the company took multiple readings none of which reached or exceeded 0.15%. The reading provided was the first readily detectable level recorded at 0.07. This report functionality rounded the number up to 0.1. Part g.5 - corrosion was on coupling not on pipe.
Detailed record list
Occurred At
2021-09-02 18:35:00
Year
2021
Report Received Date
2021-10-01 00:00:00
Iyear
2021.0
Report Number
20210084.0
Supplemental Number
40728.0
Report Type
Supplemental Final
Operator Id
2652
Name
Nstar Gas Company
Operator Street Address
157 Cordaville Road
Operator City Name
Southborough
Operator State Abbreviation
MA
Operator Postal Code
01772
Local Datetime
2021-09-02 18:35:00
Time Zone
Eastern
Daylight Savings Ind
No
Location Street Address
27 Park St
Location City Name
Maynard
Location County Name
Middlesex
Location State Abbreviation
MA
Location Postal Code
01754
Location Latitude
42.42682
Location Longitude
-71.45641
Flow Cont Service Valve Ind
Yes
Flow Cont Other Ind
Yes
Flow Cont Other Detail
Td Williamson Three Way Stoppers
Nrc Rpt Datetime
2021-09-02 19:45:00
Nrc Rpt Num
1315634
Additional Nrc Report Numbers
1315635, 1315730
Commodity Released Type
Natural Gas
Unintentional Release
1.0
Intentional Release
0.0
Fatality Ind
Yes
Num Emp Fatalities
0
Num Contr Fatalities
0
Num Er Fatalities
0
Num Worker Fatalities
0
Num Gp Fatalities
1
Fatal
1
Injury Ind
No
Injure
0
Ignite Ind
Yes
Ignite Datetime
2021-09-02 16:15:00
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
2021-09-02 18:35:00
On Site Datetime
2021-09-02 17:12:00
Confirmed Discovery Datetime
2021-09-02 16:33:00
Federal
No
Location Type
Public Property
Incident Area Type
Underground
Incident Area Subtype
Under Pavement
Depth Of Cover
48.0
Other Underground Facilities
No
Crossing
No
Pipe Facility Type
Privately Owned
System Part Involved
Other
System Part Details
Coupling On Main
Installation Year
1968.0
Material Involved
Steel
Steel Seam Type
Other
Steel Seam Type Details
Unknown At This Time
Release Type
Leak
Leak Type
Pinhole
Class Location Type
Class 3 Location
Est Cost Oper Paid
468000.0
Est Cost Prop Damage
15874.0
Est Cost Emergency
38676.0
Est Cost Other
0.0
Gas Cost In Mcf
4.606
Est Cost Unintentional Release
5.0
Est Cost Intentional Release
0.0
Prpty
522555.0
Commercial Affected
0.0
Industrial Affected
0.0
Residences Affected
1.0
Num Persons Hosp Not Ovnght
3.0
Num Injured Treated By Emt
0.0
Num Resident Building Affctd
3.0
Num Business Building Affctd
0.0
Accident Psig
58.0
Normal Psig
56.8
Mop Psig
60.0
Mop Cfr Section
192.619(C)
Maop Established Date
1970-07-01 00:00:00
Accident Pressure
Pressure Did Not Exceed Maop
Gas Odorized System Type
Drip
Gas Odorized Level
0.1
Scada In Place Ind
No
Accident Identifier
Notification From Emergency Responder
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 system never exceeded maop thus no investigation was required
Employee Drug Test Ind
No
Contractor Drug Test Ind
No
Cause
Corrosion Failure
Cause Details
External Corrosion
Internal External
External Corrosion
Visual Exam Results
Localized Pitting
Galvanic Corrosion Ind
Yes
Metallurgical Basis Ind
Yes
Underground Location
Yes
Under Cathodic Protection Ind
No
Shielding Evident
No
Cathodic Survey Type
No
Prior Damage
No
Coating Type
None
Field Applied Ind
No
Preparer Name
K******** S*****
Preparer Title
Manager Compliance
Preparer Email
K***************@e*********.com
Preparer Telephone
5088641836
Local Contact Name
K******** S*****
Local Contact Email
K***************@e*********.com
Local Contact Telephone
5088641836
Authorizer Name
K******** S*****
Authorizer Title
Manager Compliance
Authorizer Telephone
5088641836
Authorizer Email
K***************@e*********.com
Narrative
3.31/25 updated report based on PHMSA request a, b, c, d and g based upon the initial narrative provided by the maynard fire department to eversource, on september 2, 2021 at 16:14, the maynard fire department dispatched resources to 27 park st maynard, ma due to an odor call. The maynard fire department arrived on site at 16:17 to a structure fire. Eversource received a call from the maynard fire department at 16:33 notifying eversource of the subject structure fire. Eversource coordinated with the maynard fire department, massachusetts state fire marshall, and state regulatory agency on site. The situation was made safe through a mainline repair on september 3, 2021. A section of the main with a coupling was secured and delivered to the massachusetts material research facility for 3rd party analysis. Massachusetts material research's investigation of the gas main segment revealed significant corrosion on the entire outer diameter surface of the coupling tube from the soil/dirt service environment. The coupling showed significant wall thinning at isolated locations. At these isolated spots on the coupling, the pits breached through the wall thickness, which created a leak path for the gas to escape from the inside of the gas main. Massachusetts material research found the gas main to be in significantly good condition without any anomalies through the entire length of the pipe segment. Part a.4, a.12 this was the time the company commenced a leak investigation during which gas readings were detected. Part a.21 the company responded yes based upon the initial narrative provided by the maynard fire department and gas readings found in near proximity to the structure fire. Part a.21.A the time the maynard fire department arrived on site to a structure fire. Part a.21.D per "section iii. Conclusion" of the massachusetts fire district fourteen's regional fire investigation team fire origin and cause investigation report, issued to eversource on october 13, 2021, "the most plausible hypothesis is that of fuel gas explosion. It is believed to be an accidental low order fuel gas explosion caused [the] fire." part a.7,a.21.C, d2.F values defaulted to 1 and 0. The amount of gas release is unknown at this time. Part d.2.A the public and non-operator private property damage is currently based on a property assessment provided by the fire department as well as costs associated with landscaping, paving and concrete. Has been updated to reflect building and its contents estimate. Part d.2.B the repair cost includes the repair costs as well as the follow up leak survey costs part e.2 an average operating pressure was obtained prior to the incident. Part e.3.B the main was installed in 1968 pre-code. The date for maop was defaulted to 7/1/1970 as that was when 192.619(c) was established. Part e.5 the drip referenced is a drip odorizer - z9000. Part e.6 the company took multiple readings none of which reached or exceeded 0.15%. The reading provided was the first readily detectable level recorded at 0.07. This report functionality rounded the number up to 0.1. Part g.5 - corrosion was on coupling not on pipe.
| Occurred At | 2021-09-02 18:35:00 |
|---|---|
| Year | 2021 |
| Report Received Date | 2021-10-01 00:00:00 |
| Iyear | 2021.0 |
| Report Number | 20210084.0 |
| Supplemental Number | 40728.0 |
| Report Type | Supplemental Final |
| Operator Id | 2652 PHMSA Enforcement |
| Name | Nstar Gas Company |
| Operator Street Address | 157 Cordaville Road |
| Operator City Name | Southborough |
| Operator State Abbreviation | MA |
| Operator Postal Code | 01772 |
| Local Datetime | 2021-09-02 18:35:00 |
| Time Zone | Eastern |
| Daylight Savings Ind | No |
| Location Street Address | 27 Park St |
| Location City Name | Maynard |
| Location County Name | Middlesex |
| Location State Abbreviation | MA |
| Location Postal Code | 01754 |
| Location Latitude | 42.42682 Google Maps OpenStreetMap |
| Location Longitude | -71.45641 Google Maps OpenStreetMap |
| Flow Cont Service Valve Ind | Yes |
| Flow Cont Other Ind | Yes |
| Flow Cont Other Detail | Td Williamson Three Way Stoppers |
| Nrc Rpt Datetime | 2021-09-02 19:45:00 |
| Nrc Rpt Num | 1315634 NRC Report How to search |
| Additional Nrc Report Numbers | 1315635, 1315730 |
| Commodity Released Type | Natural Gas |
| Unintentional Release | 1.0 |
| Intentional Release | 0.0 |
| Fatality Ind | Yes |
| Num Emp Fatalities | 0 |
| Num Contr Fatalities | 0 |
| Num Er Fatalities | 0 |
| Num Worker Fatalities | 0 |
| Num Gp Fatalities | 1 |
| Fatal | 1 |
| Injury Ind | No |
| Injure | 0 |
| Ignite Ind | Yes |
| Ignite Datetime | 2021-09-02 16:15:00 |
| 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 | 2021-09-02 18:35:00 |
| On Site Datetime | 2021-09-02 17:12:00 |
| Confirmed Discovery Datetime | 2021-09-02 16:33:00 |
| Federal | No |
| Location Type | Public Property |
| Incident Area Type | Underground |
| Incident Area Subtype | Under Pavement |
| Depth Of Cover | 48.0 |
| Other Underground Facilities | No |
| Crossing | No |
| Pipe Facility Type | Privately Owned |
| System Part Involved | Other |
| System Part Details | Coupling On Main |
| Installation Year | 1968.0 |
| Material Involved | Steel |
| Steel Seam Type | Other |
| Steel Seam Type Details | Unknown At This Time |
| Release Type | Leak |
| Leak Type | Pinhole |
| Class Location Type | Class 3 Location |
| Est Cost Oper Paid | 468000.0 |
| Est Cost Prop Damage | 15874.0 |
| Est Cost Emergency | 38676.0 |
| Est Cost Other | 0.0 |
| Gas Cost In Mcf | 4.606 |
| Est Cost Unintentional Release | 5.0 |
| Est Cost Intentional Release | 0.0 |
| Prpty | 522555.0 |
| Commercial Affected | 0.0 |
| Industrial Affected | 0.0 |
| Residences Affected | 1.0 |
| Num Persons Hosp Not Ovnght | 3.0 |
| Num Injured Treated By Emt | 0.0 |
| Num Resident Building Affctd | 3.0 |
| Num Business Building Affctd | 0.0 |
| Accident Psig | 58.0 |
| Normal Psig | 56.8 |
| Mop Psig | 60.0 |
| Mop Cfr Section | 192.619(C) View CFR 49 §192 |
| Maop Established Date | 1970-07-01 00:00:00 |
| Accident Pressure | Pressure Did Not Exceed Maop |
| Gas Odorized System Type | Drip |
| Gas Odorized Level | 0.1 |
| Scada In Place Ind | No |
| Accident Identifier | Notification From Emergency Responder |
| 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 system never exceeded maop thus no investigation was required |
| Employee Drug Test Ind | No |
| Contractor Drug Test Ind | No |
| Cause | Corrosion Failure |
| Cause Details | External Corrosion |
| Internal External | External Corrosion |
| Visual Exam Results | Localized Pitting |
| Galvanic Corrosion Ind | Yes |
| Metallurgical Basis Ind | Yes |
| Underground Location | Yes |
| Under Cathodic Protection Ind | No |
| Shielding Evident | No |
| Cathodic Survey Type | No |
| Prior Damage | No |
| Coating Type | None |
| Field Applied Ind | No |
| Preparer Name | K******** S***** |
| Preparer Title | Manager Compliance |
| Preparer Email | K***************@e*********.com |
| Preparer Telephone | 5088641836 |
| Local Contact Name | K******** S***** |
| Local Contact Email | K***************@e*********.com |
| Local Contact Telephone | 5088641836 |
| Authorizer Name | K******** S***** |
| Authorizer Title | Manager Compliance |
| Authorizer Telephone | 5088641836 |
| Authorizer Email | K***************@e*********.com |
| Narrative | 3.31/25 updated report based on PHMSA request a, b, c, d and g based upon the initial narrative provided by the maynard fire department to eversource, on september 2, 2021 at 16:14, the maynard fire department dispatched resources to 27 park st maynard, ma due to an odor call. The maynard fire department arrived on site at 16:17 to a structure fire. Eversource received a call from the maynard fire department at 16:33 notifying eversource of the subject structure fire. Eversource coordinated with the maynard fire department, massachusetts state fire marshall, and state regulatory agency on site. The situation was made safe through a mainline repair on september 3, 2021. A section of the main with a coupling was secured and delivered to the massachusetts material research facility for 3rd party analysis. Massachusetts material research's investigation of the gas main segment revealed significant corrosion on the entire outer diameter surface of the coupling tube from the soil/dirt service environment. The coupling showed significant wall thinning at isolated locations. At these isolated spots on the coupling, the pits breached through the wall thickness, which created a leak path for the gas to escape from the inside of the gas main. Massachusetts material research found the gas main to be in significantly good condition without any anomalies through the entire length of the pipe segment. Part a.4, a.12 this was the time the company commenced a leak investigation during which gas readings were detected. Part a.21 the company responded yes based upon the initial narrative provided by the maynard fire department and gas readings found in near proximity to the structure fire. Part a.21.A the time the maynard fire department arrived on site to a structure fire. Part a.21.D per "section iii. Conclusion" of the massachusetts fire district fourteen's regional fire investigation team fire origin and cause investigation report, issued to eversource on october 13, 2021, "the most plausible hypothesis is that of fuel gas explosion. It is believed to be an accidental low order fuel gas explosion caused [the] fire." part a.7,a.21.C, d2.F values defaulted to 1 and 0. The amount of gas release is unknown at this time. Part d.2.A the public and non-operator private property damage is currently based on a property assessment provided by the fire department as well as costs associated with landscaping, paving and concrete. Has been updated to reflect building and its contents estimate. Part d.2.B the repair cost includes the repair costs as well as the follow up leak survey costs part e.2 an average operating pressure was obtained prior to the incident. Part e.3.B the main was installed in 1968 pre-code. The date for maop was defaulted to 7/1/1970 as that was when 192.619(c) was established. Part e.5 the drip referenced is a drip odorizer - z9000. Part e.6 the company took multiple readings none of which reached or exceeded 0.15%. The reading provided was the first readily detectable level recorded at 0.07. This report functionality rounded the number up to 0.1. Part g.5 - corrosion was on coupling not on pipe. |
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