A year after a natural gas pipeline exploded near Prince George, B.C., the people who felt their homes shake are still waiting for answers about what exactly went wrong and what can be done to prevent future incidents.

Approximately 100 Lheidli T'enneh residents in the community of Shelley, 15 kilometres northeast of Prince George, fled their homes as a precaution after the explosion.

They were allowed to return the same evening, and no injuries were reported.

Investigators determined the explosion was caused by a rupture in a 36-inch pipeline owned by Enbridge.

The Transportation Safety Board (TSB) then launched a more detailed analysis and is now writing a final report on the matter.

Cracks from corrosion — TSB

In June of 2019, the TSB sent a letter to Enbridge stating the likely cause of the pipeline rupture were cracks from corrosion caused by moisture.

The TSB recommended the company review its infrastructure management practices, including how often it inspects pipelines for faults.

A large fireball seen rising into the sky above Shelley, a small community about 15 kilometres northeast of Prince George after a natural gas pipeline ruptured and exploded on Oct. 9, 2018. (@Dhruv7491/Twitter)

The TSB also singled out Enbridge's use of polyethylene tape on its pipelines, writing "this type of coating has a tendency to separate (disbond) from the pipeline, allowing moisture present in the soil to contact the pipe surface."

The cause of the explosion itself has not been released.

A spokesperson for the Transportation Safety Board said a full report into the explosion — along with recommendations, if there are any — could be expected as early as January 2020, but no firm timeline has been released.

Enbridge increases inspections

In an emailed response to CBC, Enbridge said it has increased the frequency of its pipeline inspections and has already conducted system-wide checks for other corrosion.

"By November 2019, we will have nearly doubled the number of dig inspections undertaken in a typical maintenance year," the email reads. "This work goes well beyond industry standards."

Lawyer Malcolm Macpherson is representing Lheidli T'enneh in the lawsuit against Enbridge. (Andrew Kurjata/CBC)

Lheidli T'enneh pursuing legal action

Meanwhile, the Lheidli T'enneh First Nation is pursuing legal action against Enbridge, seeking financial compensation for damages, nuisance and trespass.

In its notice of civil claim, the Nation says the explosion caused "serious and constant distress and anguish" for Lheidli T'enneh members and that Enbridge has failed to adequately communicate the cause of the explosion and its aftermath.

The notice also argues Lheidli T'enneh never gave the company permission to build on its unceded land, and asks for a permanent injunction preventing Enbridge from operating on their territory and reserves, and to immediately dismantle and remove existing pipeline infrastructure.

Phyllis Seymour, a member of the Lheidli T'enneh First Nation, described witnessing the pipeline explosion as 'traumatic.' (Rafferty Baker/CBC)

In legal documents filed in response to the Lheidli T'enneh lawsuit, Enbridge says the civil claim "lacks merit" and "is an abuse of process and collateral attack." The company says it "acted in good faith to accommodate and support Lheidli T'enneh" following the explosion and the First Nation should not be entitled to damages or compensation.

In an emailed response to CBC, Enbridge said that the natural gas pipeline — which is a major supplier to customers in the Lower Mainland — is a critical piece of provincial infrastructure, used to heat homes, hospitals, schools, businesses and industry, and that it has operated safely for more than 60 years.

The company says that it has been open with the Lheidli T'enneh about the process, and that it is "always interested in strengthening our relationship with Indigenous communities."

"At Enbridge, no incident is ever acceptable," the email says. "Our goal is to continually improve the safety of our pipeline systems."

Listen to an interview with Malcolm Macpherson, the lawyer representing Lheidli T'enneh:

It was one year ago today that a natural gas pipeline exploded near Prince George. Now, the people who live near that pipeline are still waiting for answers about what went wrong, and the Lheidli T'enneh First Nation is taking legal action against Enbridge. 9:05

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