A newly released report on a fatal roof collapse at an oil sands construction site shows poor safety strategies were to blame.
The 18-page report on the death of two temporary foreign workers at Canadian Natural Resource Limited's Horizon site in 2007 was only just recently released after pressure from media.
"The normal procedure is to post these kinds of documents once the court proceedings are completed and in this case it was merely an oversight that it wasn't posted sooner," said Lauren Welsh, spokesperson for Alberta's Ministry of Labour.
Sinopec, a Chinese oil and gas company, was ordered to pay a $1.5 million fine in 2013 – the largest ever in the province.
SSEC Canada, a subsidiary company established one year before the accident to bid for work in the Alberta oil sands, pleaded guilty to three charges in connection with the incident. Originally, SSEC and CNRL faced a total of more than 50 charges, but nearly all were dropped or stayed.
The incident happened in April 2007 when workers were building a roof for a storage tank at the CNRL Horizon Oil Sands Project, located approximately 70 km north of Fort McMurray and 30 km north of Fort MacKay. At the time of the incident approximately 6,000 workers were working on the construction of the project. In April, SSEC Canada was contracted by CNRL Horizon to construct a total of 14 tanks, 11 on the east tank farm and 3 on the west tank farm at the CNRL Horizon Plant Site.
The roof is constructed onto a roof support structure consisting of vertical circular columns, supporting girders and radial rafters. The components of the roof support structure are assembled together with 19 mm nuts and bolts. At the time of the incident, a team of welders was working in the tank constructing the tank wall. Two technicians were also in the tank carrying out weld testing, and one scaffolder was inside. There was an Electrical Consultant and a welding foreman who were checking out a welding machine on top of the wall.
According to the Alberta Occupational Health and Safety report, a supporting cable snapped after high winds and kinks weakened it. Nearby workers told investigators they heard loud bangs and pops when the roof collapsed. After the roof support structure collapsed some of the workers managed to escape from the tank through manways or other holes in the tank wall.
An electrical consultant was pronounced dead at the scene. A scaffolder, who was on the tank floor, and died while being transported to Fort McMurray. Both were killed by falling steel. Two other workers received serious injuries and three more workers received minor injuries.
According to court records and reports, the construction on the storage tanks were behind schedule, so SSEC and CNRL decided to build the walls and roofs at the same time. The site's "confined space monitor" was poorly trained not competent to do their duties like raising an alarm or launching an effective rescue. There wasn't access to phones or radios and there was no communication with workers inside the tank.
According to the report, the monitor didn't even understand what his role was or what was required of him during an emergency. The report also criticized SSEC for failing to have escape plans in its emergency procedures.
Investigators found SSEC and CNRL did not check if construction drawings had been signed and stamped by an engineer and workers were only given verbal instructions for how to build the tank roof.