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Birders in the United States probably first heard of the oil extraction projects in northern Alberta last spring, when hundreds of ducks – mostly Buffleheads – were killed by landing in a bitumen tailings retention pond. While the company that built the pond may not have intended to kill the birds, the deaths were no accident. They were a predictable result of one of the worst ongoing environmental disasters in North America.
As conventional sources of petroleum are gradually being exhausted, oil companies have turned to other ways of extracting this valuable liquid. Among the new sources of fuel is tar sand oil, or bitumen. The largest bitumen deposits are in Northern Alberta, and major oil companies have been mining it as quickly as they can. Andrew Nikiforuk documents the environmental degradation that results from tar sand mining in his new book, Tar Sands: Dirty Oil and the Future of a Continent.
Unlike conventional petroleum, bitumen cannot be pumped out of the ground; it must be mined instead. The easiest way to mine bitumen is to strip all the trees and soil that covers a bitumen deposit and then dig it out with massive earth movers. The operation resembles the mountaintop removal process for mining coal in the Appalachians. The extracted tar is then boiled to separate the heavy oil from sand and clay. Deeper bitumen deposits must be extracted by pumping steam into an underground cavern and then pumping out the melted bitumen (a process called in situ mining).
For the first method, each barrel of bitumen requires two tons of earth and three barrels of fresh water. The water used to boil tar is too toxic to dump in a river (or anywhere else, really), so it is pumped into massive retaining ponds, which are themselves disasters waiting to happen if any of the dams fail. The hapless Buffleheads landed in one of these. The second method requires even more water and likewise produces toxic waste. Both methods have had a drastic impact on the local water supply. The summer flow of the Athabasca River has fallen by 30% since the 1970s because mining operations have used so much of its water. Meanwhile, in situ mining operations threaten the groundwater supply. In neither case has there been any long-term planning for drought or climate change, and Alberta's regulatory agencies have consistently overlooked the projects' environmental impacts.
Both methods contribute far more greenhouse gases than conventional oil extraction as bitumen mining is highly energy intensive.
Nikiforuk suggests some remedies for the ongoing tar sands abuses. Unfortunately almost all of them rely on either the Canadian or American government to provide adequate regulation and energy planning to reduce the environmental impacts of tar sands mining and shift to sustainable energy. Given that both governments are captive to oil interests (as Nikiforuk demonstrates), I have trouble seeing this happening.
For this week only, Tar Sands is available as a free download at its publisher's website. Bloggers who link to the download site can receive a free hard copy of the book in addition to the pdf.
