Pipeline Explosion

Stress corrosion cracking led to 2018 pipeline explosion near Prince George

Mar 4, 2020 | 8:55 AM

PRINCE GEORGE, B.C. — The Transportation Safety Board of Canada, in its investigation report released today, found that stress corrosion cracking led to a pipeline rupture and fire northeast of Prince George, on October 9, 2018.

Deficiencies in predicting the extent of cracking of the 36-inch natural gas pipeline operated by Westcoast Energy Inc., and a deferred inspection, led to a hazard being undetected prior to the pipeline rupture.

“The pipeline operator had a stress corrosion cracking hazard management plan in place for this pipeline,” reads the report. “However, the extent of the existing crack growth did not take into account all potential uncertainties in the predicted crack growth. This resulted in cracks growing at higher rates than the model predicted. Additionally, an inspection of this pipeline segment scheduled for 2017 was deferred until the fall of 2018. As such, the existing cracks remained unchecked.”

The report goes on to say that although emergency response activities were successful in mitigating the impacts of the occurrence, the investigation determined that during periodic emergency response exercises in the four years prior to the occurrence, not all nearby communities and operators of nearby pipelines were included.

“If pipeline emergency response exercises are not conducted periodically with all potentially affected stakeholders, gaps in emergency response plans may not be identified, thereby increasing the risk that all parties will not be sufficiently prepared to respond to a pipeline emergency,” says the report.

There were no injuries in the blast, however, 125 people within a 2 km radius were forced to flee as a precaution. The explosion sparked a massive blaze.

Enbridge released the following statement in response to the report:

“We know this incident has caused concerns and disrupted the lives of many people in the area. For that, we apologize,” said Michele Harradence, Senior Vice President and Chief Operations Officer, Gas Transmission and Midstream for Enbridge. “We commit that we have learned from this incident and have taken steps to ensure the safety of our natural gas system.”

To that end, Enbridge says it has completed a comprehensive pipeline integrity program on its natural gas pipeline system in B.C. to prevent similar incidents from occurring and to significantly improve pipeline safety.

The company says it’s the most aggressive integrity program ever undertaken by Enbridge on its pipeline system in B.C. The company says it’s part of a new approach to pipeline safety and an ongoing commitment to continually improve the safety of our natural gas pipeline system.