Where the trapline and the cabin once were, and the forest, there is now a large open-pit mine. Here Syncrude, Canada’s largest oil producer, digs bitumen-laced sand from the ground with electric shovels five stories high, then washes the bitumen off the sand with hot water and sometimes caustic soda. Next to the mine, flames flare from the stacks of an “upgrader,” which cracks the tarry bitumen and converts it into Syncrude Sweet Blend, a synthetic crude that travels down a pipeline to refineries in Edmon ton, Alberta; Ontario, and the United States. Mildred Lake, meanwhile, is now dwarfed by its neighbor, the Mildred Lake Settling Basin, a four-square-mile lake of toxic mine tailings. The sand dike that contains it is by volume one of the largest dams in the world…
Nowhere on Earth is more earth being moved these days than in the Athabasca Valley. To extract each barrel of oil from a surface mine, the industry must first cut down the forest, then remove an average of two tons of peat and dirt that lie above the oil sands layer, then two tons of the sand itself. It must heat several barrels of water to strip the bitumen from the sand and upgrade it, and afterward it discharges contaminated water into tailings ponds like the one near Mildred Lake. They now cover around 50 square miles. Last April some 500 migrating ducks mistook one of those ponds, at a newer Syncrude mine north of Fort McKay, for a hospitable stopover, landed on its oily surface, and died. The incident stirred international attention—Greenpeace broke into the Syncrude facility and hoisted a banner of a skull over the pipe discharging tailings, along with a sign that read “World’s Dirtiest Oil: Stop the Tar Sands.”[…]
“Oil sands represent a decision point for North America and the world,” says Simon Dyer of the Pembina Institute, a moderate and widely respected Canadian environmental group. “Are we going to get serious about alternative energy, or are we going to go down the unconventional-oil track? The fact that we’re willing to move four tons of earth for a single barrel really shows that the world is running out of easy oil.”[…]
Without the [Athabasca River], there would be no oil sands industry. It’s the river that over tens of millions of years has eroded away billions of cubic yards of sediment that once covered the bitumen, thereby bringing it within reach of shovels—and in some places all the way to the surface. On a hot summer day along the Athabasca, near Fort McKay for example, bitumen oozes from the riverbank and casts an oily sheen on the water. Early fur traders reported seeing the stuff and watching natives use it to caulk their canoes. At room temperature, bitumen is like molasses, and below 50°F or so it is hard as a hockey puck, as Canadians invariably put it. Once upon a time, though, it was light crude, the same liquid that oil companies have been pumping from deep traps in southern Alberta for nearly a century. Tens of millions of years ago, geologists think, a large volume of that oil was pushed northeastward, perhaps by the rise of the Rocky Mountains. In the process it also migrated upward, along sloping layers of sediment, until eventually it reached depths shallow and cool enough for bacteria to thrive. Those bacteria degraded the oil to bitumen…
And every day in the Athabasca Valley, more than a million tons of sand emerges from such crushers and is mixed with more than 200,000 tons of water that must be heated, typically to 175°F, to wash out the gluey bitumen. At the upgraders, the bitumen gets heated again, to about 900°F, and compressed to more than 100 atmospheres—that’s what it takes to crack the complex molecules and either subtract carbon or add back the hydrogen the bacteria removed ages ago. That’s what it takes to make the light hydrocarbons we need to fill our gas tanks. It takes a stupendous amount of energy. In situ extraction, which is the only way to get at around 80 percent of those 173 billion barrels, can use up to twice as much energy as mining, because it requires so much steam.
Most of the energy to heat the water or make steam comes from burning natural gas, which also supplies the hydrogen for upgrading. Precisely because it is hydrogen rich and mostly free of impurities, natural gas is the cleanest burning fossil fuel, the one that puts the least amount of carbon and other pollutants into the atmosphere. Critics thus say the oil sands industry is wasting the cleanest fuel to make the dirtiest—that it turns gold into lead. The argument makes environmental but not economic sense, says David Keith, a physicist and energy expert at the University of Calgary. Each barrel of synthetic crude contains about five times more energy than the natural gas used to make it, and in much more valuable liquid form.
McEachern, who works for Alberta Environment, a provincial agency, says the tailings ponds are his top concern. The mines dump waste water in the ponds, he explains, because they are not allowed to dump waste into the Athabasca, and because they need to reuse the water. As the thick, brown slurry gushes from the discharge pipes, the sand quickly settles out, building the dike that retains the pond; the residual bitumen floats to the top. The fine clay and silt particles, though, take several years to settle, and when they do, they produce a yogurt-like goop—the technical term is “mature fine tailings”—that is contaminated with toxic chemicals such as naphthenic acid and polycyclic aromatic hydrocarbons (PAH) and would take centuries to dry out on its own. Under the terms of their licenses, the mines are required to reclaim it somehow, but they have been missing their deadlines and still have not fully reclaimed a single pond.
