Concrete collapse at Muskrat Falls megaproject under investigation

One worker has been sent to hospital after concrete formworkcollapsed at theMuskrat Fallshydroelectricconstructionsite in central Labrador, raising new questions about the progress of the much-delayed and over-budgetmegaproject.

Seven other workers also received first aid after the collapse, which happened at theproject's powerhouse close to midnight Sunday.

Officials say the one worker who was taken to hospital did not sustainserious injuries.

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"This is a very, very serious incident for us," saidGilbert Bennett,NalcorEnergy's vice-president responsible for the Lower Churchill project, confirmed thatdrying concrete fell whenformwork a mould collapsed in the powerhouse.

Concrete was being poured to construct the lower draft tube, essentially a large pipe that willreturnwater to the Churchill River.

"Any time that we have something that was unplanned like this event, and we see potential for worker injury, it's one that we take very seriously," said Bennett.

What workers say happened

Multiple sources told CBC News that workers had been pouring concretefor hours and that the formworkcollapsed, coating a couple of workers in wetconcrete.

"Shaken up is an understatement," one workertold CBC News.

"I could have lost some of my brothers tonight. We are very lucky to not have lost anyone."

The collapse happened during the night shift. Employees were reportedly on their lunch breakwhen the form gave out.

Investigationlaunched

In an interview with CBC News on Monday, Bennett said that the company has launched a full investigation to find out what happened at the powerhouse, ashas Astaldi Canada, the contractor on site.

"We need to look at all aspects of the workand understand what the root cause was," he said.

"So we're interested, Astaldi isinterested, provincial Occupational Health and Safety are interested."

Bennett said that the piece of failed of equipment was manufactured in the United States, but assembled onsite by the project's main contractor, Astaldi.

Controversial project

The Muskrat Falls project is one of the most controversial issues in Newfoundland and Labrador, with skepticism amongkeymembers of the newly elected Liberal government about how Nalcor has managed the megaproject.

First power at Muskrat Falls was originally expected in December 2017.Last fall, Nalcor pushed the project's projectedstart date into 2018 and has since declined to comment on a potential start date.

Bennett said he would not speculate on how the incident will affect the project's timeline. Similar work is plannedin other parts of the construction site, but it has been paused pending the investigation.

"First and foremost, we need to understand that the work can be undertaken safely and that we can continue with this activity," he said.

Stan Marshall,Nalcor's new CEO,is reviewing the project, but said earlier this month that it is "very unlikely" that the megaproject will be cancelled.

The current cost forecast is $7.7 billion, but that number is expected to increase. It was originally estimatedthe project wouldcost $6.2 billion.At the end of 2015, $4.4 billion had been spent.

It's the most costly project in the history ofNalcor, the Crown-owned energy corporation.