Inter Press Service: The wheels of the Caterpillar 797B, the world’s largest truck, are always going round and round at Shell Canada’s Albian Sands mine. The massive dump trucks, with wheels standing twice the size of a person and tires costing some 40,000 dollars apiece, carry tar sand 24 hours a day, seven days a week. “There isn’t a lot of work in Newfoundland [a traditionally poor province on Canada’s Atlantic coast], so you can do pretty well out here,” Brian Paley, a mechanic who fixes and …