About a year ago we discussed the Tar Sands Impact on Climate Change. From a climate perspective, tar sands well-to-tank carbon emissions are approximately 82% higher than conventional oil, well-to-wheel (extraction to combustion) emissions are 10 to 45% higher, and the proposed Keystone pipeline would represent somewhere in the ballpark of 1 billion tonnes of CO2-equivalent emissions over the project's lifetime.
This is not a climate catastrophe-causing quantity of carbon emissions (try saying that 5 times fast). For example, the Australian Climate Commission's The Critical Decade report concluded that humanity has a budget of 1 trillion tonnes of CO2 between 2000 and 2050 to have a probability of about 75% of limiting global warming to 2°C or less. Thus 1 billion tonnes from the Keystone pipeline and tar sands is not going to break the budget. However, exploiting the tar sands is a conceptual step in the wrong direction. We need to start looking at fossil fuels as a natural form of carbon sequestration, not trying to find new unconventional sources of fossil fuel carbon to release into the atmosphere. As Andy S noted, exploitation of the tar sands would be the equivalent of adding another of Pacala and Socolow's "stabilization wedges" - a chunk of carbon emissions reductions, and we might already need to implement as many as 16 of these wedges. This will be a huge challenge, and adding more wedges just makes the task all the more difficult.
As we discussed a year ago, the tar sands have some other very nasty environmental impacts, as is clear in aerial photographs of the region from Google (Figure 1).
Figure 1: 2011 Google aerial photograph of the Athabasca tar sands. The photograph is approximately 30 miles across. The most clearly visually impacted area is approximately 15 miles across.
As this photograph shows, tar sands mining opearations result in significant destruction of the boreal forest. Some scientists have raised concerns that the tar sands may be causing aquatic life deformities downstream. Kelly et al. (2010) found a number of pollutants downstream of the tar sands. Rooney et al. (2011) found that tar sands mining is causing massive loss of Canadian peatland and associated carbon storage.
Additionally, there are always concerns about environmental impacts related to potential oil spills and leaks. On a similar pipeline, Keystone I, there were 12 spills over a period of less than a year, during its first year in operation. Keystone I had more spills in its first year than any other first-year pipeline in US history. It was predicted to leak once ever seven years, but instead it leaked 12 times in its first year. And we now have details regarding a tar sands oil spill which raise even greater concerns about the potential environmental impacts if the latest Keystone pipeline proposal is approved.
Enbridge is a Canadian pipeline builder which operates a pipeline going from the Alberta tar sands through Michigan in the northern United States. Reports have shown that Enbridge knew of cracks in the pipeline for five years, but failed to address them. The pipeline started leaking on July 25, 2010, and oil gushed from the rupture for more than 17 hours before the leak was discovered. More than 3 milllion liters (850,000 gallons) of tar sands crude (bitumen) spilled into Talmadge Creek, which flows into the Kalamazoo River. A 25-mile (40-kilometer) stretch of river was contaminated.
Two years later, most of the closed section of the Kalamazoo River has finally been reopened to the public after an $800 million cleanup, the most expensive onshore cleanup in US history. The cleanup took such a long time because instead of remaining on top of the water, as most conventional crude oil does, the bitumen gradually sank to the river's bottom, where normal cleanup techniques and equipment were of little use.
There have been a number of good articles and reports covering the recent events covering this disastrous spill. For more details, see Deep Climate, Inside Climate News, CBC News, a Wikipedia entry, and this good story on The Rachel Maddow Show:
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Ultimately the disaster was caused by a number of contributing factors.
None of the problems which led to this environmental disaster have been resolved.
Just this past month there have been three pipeline spills in Alberta, with Enbridge's latest spilling 230,000 liters (65,000 gallons) of crude oil onto farmland. A new NWF report details that over the past 12 years, Enbridge is responsible for 804 spils and a total of nearly 7 million gallons of oil spilled in the U.S. and Canada.
One benefit, for those looking for a silver lining on this environmental disaster cloud, is that the Enbridge Kalamazoo fiasco has generated a great deal of opposition to building the tar sands Northern Gateway pipeline through British Columbia (BC), which represents a very large environmental risk (as Enbridge showed) to BC with little benefit to its residents.
Combining the associated climate impacts with the exceptionally poor environmental track record and the inevitability of future tar sands oil leaks, it becomes extremely difficult to justify exploiting this resource rather than simply leaving the fossil fuel carbon in the ground. The economics are a clear motivator for the local Alberta government, although the damage done to the local boreal forest and water quality certainly detracts significantly from that. From an American perspective, while importing oil from our neighbors to the north may be preferred to other potential sources in less politically stable and friendly regions, the unavoidable associated climate and environmental damage should far outweigh that benefit.
There are far better alternatives to finding new unconventional fossil fuel sources. Rather than continuing to feed our addiction to oil, we need to focus on developing and implementing low-carbon alternatives, or the climate and environmental consequences will be as ugly as those experienced by Michigan.
On a lighter note, the Post Carbon Institute has put together a great video on why America needs to break-up with the Keystone tar sands pipeline for good (h/t Climate Progress).
Posted by dana1981 on Thursday, 26 July, 2012
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