The tar sands found deep beneath Alberta's vast old-growth forests are made up of 90 percent sand, clay, silt, and water and 10 percent bitumen, a tarlike substance that can be converted to oil. Currently, most tar sands production relies on open pit mines, some as large as three miles wide and 200 feet deep. Because less than 20 percent of the oil-producing bitumen deposits are close to the surface, the rest of the deep reserves must be extracted by injecting steam underground and pumping out the melted bitumen. The amount of natural gas used daily during these processes could heat about four million American homes. Once separated from the sand, clay and silt, the bitumen is still of low grade and must undergo yet another energy-intensive process to turn it into a crude oil that more closely resembles conventional oil.
Over the past ten years, oil production from Alberta's tar sands has doubled to more than one million barrels per day. Seventy-five percent of that oil is bound for the United States as both raw and refined products. Driven by skyrocketing U.S. demand, the tar sands rush has spawned a rapidly expanding web of pipelines, roads and wells that threatens to destroy and fragment more than 55,000 square miles of boreal forest habitat -- an area the size of Florida. Just a few square miles of these wildlands can support as many as 600 breeding pairs of migratory birds, many of which are now at risk of losing critical habitat from the logging and toxic pollution that go hand in hand with tar sands extraction. For indigenous peoples, mining in the region is reducing local water supplies, increasing water pollution and heightening their exposure to dangerous toxic substances.
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