A year after an explosion at Nexen's Long Lake facility in northern Alberta killed two men, their families say they haven't received any clear answers from the company.

"They basically said it was Drew and David's fault for the explosion," Tracy Foster said. "They gave no reason to us other than they were working out of scope. What does that mean?"

A box of tissues sat between Foster and her son Justin as the two spoke at the family's kitchen table in Fort McMurray. The Fosters said they've been left in the dark.

Maintenance workers Drew Foster and Dave Williams died after an explosion Jan. 15, 2016 at Nexen's Long Lake oilsands extraction project, 40 kilometres south of Fort McMurray.

The men were refitting the valves on a compressor in the gas compression building in the hydrocracker unit, where hydrogen is combined with partially upgraded oil to remove sulphur and make synthetic crude.

Foster, 52, died on site. Williams, 30, died after being hospitalized in critical condition in the burn unit at the University of Alberta Hospital in Edmonton.

An explosion Jan. 15, 2016 t Nexen's Long Lake facility killed maintenance workers Drew Foster, left, and David Williams. (CBC)

In an email statement Tuesday, Nexen said it has provided the families with as much information as possible.

"This was a tragic incident that has changed our organization," corporate communications manager Brittney Price said.

"We have taken several meaningful steps to improve our safety culture and safe work processes. Our thoughts and deepest sympathies are with the families in this difficult time."

The day after the explosion, Nexen's chief executive described the incident as "one of the darkest days in Nexen history."

Last July, the company submitted an internal investigation report to Alberta Occupational Health and Safety and said it could not comment until the government's own investigation is completed.

At the same time Nexen, a wholly-owned subsidiary of CNOOC Ltd., announced it would lay off 350 employees after shelving plans to restart the upgrader damaged in the explosion. The facility has not reopened.

Alberta OHS says its own investigation is ongoing. In an email, it said the fatality investigation report won't be released until the investigation and any possible court proceedings have been concluded.

The explosion came six months after a July 2015 incident in which a pipeline spilled five million litres of water, sand and bitumen at the Long Lake facility The Alberta Energy Regulator ordered Nexen to suspend operations on 95 pipelines at the site.

A view of the heavily damaged gas compression building in the hydrocracker unit after an explosion that killed two workers. (Nexen)

Tracy Foster said her family's tragedy has been marked by silence. The family first heard about the accident through the media, not from Nexen. Last fall they tried to schedule a meeting with the company, but officials weren't available and haven't rescheduled.

'I mean, that's my child'

One of the rooms in Bernice Williams' Cape Breton home is filled with candles and pictures of her son. She makes a point to visit David's grave every day.

Anger rages in her when she thinks about David's ordeal, but it soon melts into sadness when she thinks about how much she misses him.

David Williams' mother Bernice says she thinks about her son all the time. (Gary Mansfield/CBC)

Like the Fosters, Bernice feels as if her family has been forgotten by Nexen.

"They don't want to tell you nothing," Bernice said.

The mother said email, calls and meetings with Nexen haven't yielded any information other than the two men were to blame for the workplace accident.

"It's sad. I want to know what happened to my kid," Bernice said, "I mean, that's my child."

'I am the man of the family'

The Fosters await the completion of the Alberta OHS investigation. They say they haven't prejudged the results and are open to whatever it finds.

"We have faith in at least Alberta OHS," Tracy said. "Accidents happen. And Drew was the type of person if something went wrong, he would own it."

Justin Foster and his mother, Tracy, at their Fort McMurray home. (David Thurton/ CBC)

The loss of their main breadwinner means the family, originally from Niagara, Ont., is living paycheque to paycheque in Fort McMurray.

"I'm paying the bills but that's all I can do," Tracy said. "We came here to better our lives. This was Drew's dream."

Son Justin, 22, said he feels he now has to step up and help his mom and two sisters.

"I was a kid a year ago. Now I am the man of the family," he said. " I feel like I have to take the weight of the world on."

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