climate change > newsfile > tar sand mining growing at huge environmental cost
Tar sand mining growing at huge environmental costPosted: 23 Aug 2007
Canadian tar sands deposits hold an estimated 1.7 trillion barrels of crude oil, second in the world only to Saudi Arabia, but the devastating environmental impact of mining them far exceeds that of conventional oil, says new research to be published next month (September 2007).
According to the September-October issue of World Watch magazine the energy-intensive process of extracting crude bitumen from the mixture of sand, clay, and silt releases up to three times more greenhouse gas pollution than conventional oil extraction and is wreaking havoc on local forests, wildlife, fresh water resources, and air quality.
"Everything about the tar sands is big," says Dan Woynillowicz in his article Tar Sands. "Most significantly its global warming and environmental implications - leading some to now describe the tar sands as 'Canada's dirty secret.'"
The tar sands deposits underlie more than 140,000 square kilometres of relatively pristine Canadian boreal [northern] forest, which accounts for one-quarter of the world's remaining intact forests. If currently planned tar sands development projects go forward, approximately 3,000 square kilometres of boreal forest could be cleared, drained, and strip-mined.
The remaining 137,000 square kilometers stand to be compromised by the extraction process used for deeper reserves, which requires injecting high-pressure steam into the ground to soften the bitumen so it can be pumped to the surface.
The mining of the tar sands is also diverting streams and rivers and draining large amounts of water from the nearby Athabasca River, the primary source of the water used in the separation process. Tar sands mining operations withdraw 2 to 4.5 barrels of fresh water from the
river for every barrel of oil produced, threatening the sustainability of local subsistence and commercial fisheries and the habitat of a wide variety of wildlife.
The United States currently receives 99 per cent of Canadian crude oil exports. While this accounted for only 7 per cent of US daily
consumption in 2005, tar sands production and development has grown dramatically in recent years, and more than $100 billion of investment
has been announced for development over the next decade.
Referring to the US. "addiction to oil," Woynillowicz observes: "Most of us regard addictions as inherently unhealthy and admission of the problem as the first step toward getting clean. In this case, however, US policy has simply been to seek increased oil imports from more reliable sources closer to home - in effect, to replace distant and unstable dealers with one from the neighbourhood."