ARCHIVED - FAQs – Final Investigation Report: Enbridge Gas Distribution Inc

This page has been archived on the Web

Information identified as archived is provided for reference, research or recordkeeping purposes. It is not subject to the Government of Canada Web Standards and has not been altered or updated since it was archived. Please contact us to request a format other than those available.

The NEB has investigated the cause of a gas release within the boundaries of Enbridge Gas Distribution Inc’s (EGD) Lisgar Gate Station in Mississauga, Ontario that occurred on 30 September 2009. The full findings are available in the attached report.

Below, for your information, are some questions and answers
on the NEB’s investigation into the incident.

What were the impacts to people and the environment as a result of the incident?

The gas ignited, damaging a building and destroying several vehicles and construction equipment that were in the immediate vicinity of the gas leak. No workers or members of the public were injured. Adjacent businesses, including a strip mall and day care, were evacuated as a precautionary measure.

Damage to the environment was limited to local soil and vegetation inside the fenced area of the station property.

NEB staff determined there were no further threats to people or the environment after the initial impacts.

What was the NEB’s immediate response following the incident?

The Board deployed NEB staff to the incident site to ascertain facts related to the incident and to determine the cause and contributing factors that led to the incident.

As a part of its investigation, the NEB directed EGD to arrange for a third party to conduct a metallurgical analysis of the evidence gathered from the incident site.

Was any action taken against Enbridge Gas Distribution Inc. as a result of the incident?

The Ontario Ministry of Labour charged EGD and its contractor with violations to the Ontario Occupational Health and Safety Act, to which both parties eventually pleaded guilty.

In addition to its investigation and findings, the NEB will be conducting targeted compliance verification activities with EGD in order to verify that corrective actions have been adequately implemented to address the systemic factors identified in the report.

What caused the gas to ignite?

The gas release was caused when contact was made with a threaded nipple on a blind flange that had been installed on the end of a length of pressurized pipe. The released gas ignited when the gas encountered an ignition source.

The NEB also identified other factors that contributed to the event such as:

  • Inadequate contractor oversight;
  • Ineffective operational control;
  • Inadequate communication between company and contractor staff; and
  • Inadequate hazard identification and mitigation

In addition to the immediate cause of the gas release and fire, what other findings did the Board make as a result of its investigation?

The Board found that EGD did not demonstrate:

  • compliance with Section 31 of the Onshore Pipeline Regulations, 1999 (OPR-99) by failing to have a copy of its maintenance safety manual on site;
  • compliance with Section 29 of the OPR-99 by failing to adequately communicate hazards to contracted workers;
  • adequate hazard identification and risk assessment of the 24 inch pressurized pipeline system at the Lisgar Gate Station;
  • adequate contractor oversight by failing to ensure that the requirements for conducting ongoing hazard identification and risk assessments were met;
  • control of its contractor by failing to ensure that the contractor adhered to the supervision of pipe lowering-in procedures as required by EGD’s policies;
  • adequate communication of hazards, risks and mitigation, which led to inadequate control of activities occurring at the maintenance site; and
  • adequate contractor oversight and control by ensuring that the requirements for the safety meetings and work permits as outlined in the contract were met.

Why were these findings of concern to the Board?

The Board found that the gas release and fire that occurred were preventable. Though no people were injured and the incident resulted in minimal impacts to public safety, the environment or the economy, the potential impact of an event of this magnitude cannot be ignored.

The NEB expects its regulated companies to anticipate, prevent, manage and mitigate potentially dangerous conditions associated with its pipelines. As part of this, the Board expects pipeline companies to continually improve in the areas of safety, security and environmental protection. They must also promote a positive safety culture as a part of their management system.

The company must demonstrate to the NEB that the corrective actions that have been implemented since the incident are in use, as well as being adequate and effective.

What actions has the Board required EGD to take as a result of the findings in this report?

EGD will be required to demonstrate to the Board the implementation of measures to prevent a recurrence.

The NEB will also be conducting targeted compliance verification activities with EGD in order to verify that their corrective actions have been adequately implemented to address the systemic factors identified in the report.

What oversight did the NEB take to monitor Enbridge Gas Distribution Inc. during the period covered by the investigation?

During the period covered by the investigation, the NEB conducted targeted compliance activities that related directly to areas of concern as a result of the ongoing investigation. These included:

  • scrutinizing any new EGD applications to ensure compliance with NEB regulations and safety standards; and
  • compliance meetings between EGD and Board management to ensure the company understood the NEB’s expectations regarding improvements required.

The NEB continues to monitor EGD and more specifically areas of concern identified in this report, as a part of its routine compliance verification activities with the company.

Why did it take the NEB so long to release this report?

The NEB’s investigation spanned September 2009 to March 2011, however it was not concluded until after court proceedings between parties to this incident has been finalized, allowing the NEB to consider these findings as a part of the investigation.

The publishing of this report concludes the NEB’s investigation into this incident.

Date modified: