Members of the Lheidli T'enneh First Nation near Prince George in central B.C. say they're worried after homes were rocked by a pipeline explosion Tuesday, despite assurances from Enbridge — the company that owns the pipeline — that safety is its top priority.

Phyllis Seymour said her entire house shook when the natural gas line exploded at about 5:45 pm PST. She thought it was thunder until she looked out the window to see flames shooting into the air.

"To see that big fireball, it was so scary," she said. "You wouldn't even believe it was happening."

Phyllis Seymour described witnessing Tuesday's natural gas fire as 'traumatic.' (Rafferty Baker/CBC)

Roughly 100 residents of the reserve land north of the Fraser River fled to Prince George, 13 kilometres away, following the explosion. Though they were given the all-clear to go home within hours, many chose to spend the night in hotels, unwilling to take any risks.

Returning home Wednesday, Seymour said she still felt uneasy.

I'll be scared to go to bed tonight. - Phyllis Seymour, Lheidli T'enneh member

"Like, is this gonna blow up?" she asked, gesturing to pipeline apparatus alongside the road leading to her home. "I'll be scared to go to bed tonight."

A large fireball was seen rising into the sky from Shelley, B.C., a small community about 15 kilometres northeast of Prince George. (@Dhruv7491/Twitter)

So far, little is known about what caused the incident except that there was a rupture on a 36-inch natural gas transmission line owned by Enbridge. The line is part of a system that transports natural gas from northeastern B.C. south to the Lower Mainland and some customers in the United States.

Police have ruled out a criminal cause, leaving the investigation in the hands of the Transportation Safety Board, the National Energy Board and Enbridge to determine what went wrong.

An employee of Enbridge monitors pipeline equipment near Prince George, B.C., following an explosion and fire caused by a rupture on Oct. 9. (Rafferty Baker/CBC)

The initial fieldwork is expected to be complete within days, while the full investigation will extend over several weeks, leaving people who live near the site of the explosion with unanswered questions about what happened, and the integrity of the pipelines that pass near their homes.

We need to understand what happened here and how we can make sure it doesn't happen again. - Michele Harradence , Enbridge

"I am concerned, I've always been concerned," said Violet Bazoki, who wasn't home when the explosion happened, but could see the smoke from over 30 kilometres away.

Bazoki recalled a meeting of band members earlier in the year in which another resident asked if there was any risk of the pipeline exploding.

"[Now] something did happen," she said.

Violet Bazoki said she's long been worried about the safety of pipelines running through her community, particularly the risk of an explosion or fire cutting off the only road in and out. (Andrew Kurjata/CBC)

National Energy Board chief engineer Iain Colquhoun explained his organization's role is to make sure Enbridge is handling the situation properly, as well as ensuring no other pipelines in the area are at risk. The board has already determined that a nearby 30-inch pipeline — which was shut down Tuesday as a precaution — is safe. It has allowed gas to flow through it once again.

Speaking from Calgary, Colquhoun said the last recorded pipeline rupture and explosion in Canada was in 2013.

"It's quite an unusual event," he said.

The pipeline is part of the T-South system which stretches over 1,000 kilometers from Chetwynd to the B.C.-US border, passing through several communities. (Enbridge )

Likewise, Lheidli T'enneh Chief Dominic Frederick said he wasn't particularly worried Tuesday's explosion would be repeated.

"[The pipelines] have been there for over sixty years," he said. "We've never had any concerns until now."

Michele Harradence, a senior vice president with Enbridge, said she held herself personally accountable for the safety of the pipeline and those around it.

Several pipelines cross through Lheidli T'enneh, a First Nations community along the Fraser River northeast of Prince George, B.C. (Rafferty Baker/CBC)

"It's very understandable that folks are concerned, I don't blame them," she said. "It's extremely distressing to see something like this."

Harradence said the company regularly inspects its pipelines and was concerned the rupture occurred despite those safety measures.

"We need to understand what happened here and how we can make sure it doesn't happen again," she said.

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