Excerpt from the OH&S Canada magazine
Authorities are investigating an incident involving a worker who died when his bulldozer crashed through the ice of Cree Lake of Saskatchewan.
On February 21, 2011, the Buffalo Narrows RCMP received a report that a worker and the D-6 Caterpillar bulldozer he was operating had fallen through the ice in about 10 metres of water. The body of 54-year-old employee of DJ Drilling (2004) Ltd. was later recovered.
Provincial health and safety officials are investigating and the coroner is assisting, notes a statement from the RCMP.
DJ Drilling was serving as the drill contractor on the Cree east project on behalf of CanAlaska Uranium Ltd., which has a uranium mine approximately 600 kms northeast of Buffalo Narrows.
The operator, who had flown into camp the night before, was using a bulldozer to clear snow off the ice to prepare for a new drill pad. Three holes had already been drilled between the camp and the drill site, about 2 kms away.
The worker spoke with the drill foreman about 10 minutes before the incident, says Emil Fung, director and vice-president of corporate development with CanAlaska in Vancouver. “When the drill foreman looked behind in his rearview mirror, he couldn’t see the bulldozer anymore,” Fung says.
He notes the driller and crew had earlier checked ice thickness every 50 metres along the path of the intended drill route. The measurements showed about 75cm “of thickness of ice, which is adequate to sustain the equipment.”
The company suspended operations and removed the entire camp, leaving behind a skeleton crew.
Kerry Willet, a consultant/trainer at Workplace Safety North in North Bay, Ontario, says calculating recommendations for ice thickness in “complicated” and influenced by many factors, including the type of ice.
Blue ice is clear in texture and has the maximum allowable load bearing capacity, while white ice has only 50 % of that load bearing capacity, reports Manitoba Transportation and Government Services in Winnipeg. Grey ice, for its part, is formed from thawing and should not be trusted as a load bearing surface.
Load duration, ice cover type, load weights, schedule and operating window, and contractor capability/experience which includes worker training) must all be taken in consideration when planning for operations over ice, notes the document, “Best Practice for Building and Working Safely on Ice Covers in Alberta.”
Workplace parties, must conduct a hazard assessment and develop an ice safety plan. The plan should be communicated to all employees affected by the ice cover hazards and periodically reviewed and updated as needed.
Willet says one good safety measure available before work begins is to secure an understanding of the history of the water being crossed and current locations. “As you are travelling across this large skim of ice, which might be like a paper plate, you actually get water moving underneath it,” he explains.
This movement creates waves under the ice that becomes amplified as they travel to shore and back towards where the wave was initiated, creating instability, Willet advises.
Unpredictable or harsh weather conditions may also come into the mix. “It’s just like being out in a big field and a blizzard comes up and you can’t even tell which direction to even turn after you walked 10 paces,” Willet says. “You can wander around in circles and never find your way back.”
My opinion,
There was a lot of good advice given here and to certainly conduct a hazard assessment prior to any work is to be done is one of the most important. I was especially impressed with the details given by Kerry Willet on the different load bearing capabilities of the different coloured ice. Very interesting!
My next question is this. Why did the CanAlaska company not have hired someone such as Kerry Willet to at least complete a hazard assessment? Why was the operation taken place without all the facts? Where was the “competent’ supervisor in all this?
In closing,
I am always saddened by the fact that legislative changes almost always occur after an extreme accident/incident. Why do shortcuts always have to take place on many jobsites and why does the practice of safety be given such a low priority?
Good questions, right? I bet you, the reader has thought of this too. If not, then it is food for thought.
Ensure your workplace is a safe place.
Remember – In Canada, “ALL Accidents are Preventable”
‘Work’ and ‘Play’ safe.
Daniel L. Beal
CHSEP – Advanced Level
VP & Senior Trainer
HRS Group Inc.
I wanted to thank you for all the great information.