Thursday afternoon, fire broke out at the Horizon oilsands site near Fort McKay in northern Alberta.  Canadian Natural Resources Ltd., which owns the site, confirmed that the fire was set off by an explosion around 5:30 PM Eastern Time Thursday.

The fire itself started in an upgrader across from the plant where bitumen is converted into crude oil.  The 480-foot coker structure, which uses heat to convert bitumen into crude oil caught fire.  Individuals at the site claimed that the explosion caused flames and smoke to shoot hundreds of feet into the air. 

Four employees sustained injuries from the blast, two of whom were treated on site.  The other two were taken to hospital with first, second, and third degree burns.  All other employees have been accounted for.

The Thursday afternoon explosion forced Canadian Natural Resources to stop to production at their site that produced just over 90,000 barrels per day in 2010, or roughly six per cent of Canada’s oil sands output. Though there is no indication of how long the outage might last, similar oil sands fires have halted production for as long as eight months. 

An investigation has been initiated into the blast to examine possible safety violations. 

Canadian Natural Resources is already under investigation for an earlier safety violation where two employees from China died when the tank they were working on collapsed in 2007.  There were also allegations that these employees were being underpaid for their work. 

In addition to safety violations, Canadian Natural Resources also claimed the the air quality in Fort McKay to be good 2.5 hours after the blast.  Residents of the community reported nausea and headaches, and disputed Canadian Natural Resources readings. 

Read on about this growing story here. 

Image Credits: CBC