Last February, the largest environmental rally in U.S. history took place in Washington. Nearly 40,000 people marched on the White House in an effort to bring President Barack Obama’s attention to the possible dangers of the Keystone XL Pipeline, a system to be constructed over 2,000 miles for the transport of crude oil from Canada to Texas. Despite their efforts, the president’s most recent statements claim that the pipeline will be approved if it is not shown to “significantly exacerbate the problem of carbon pollution,” which is the official position of the U.S. State Department. Some protesters, disheartened by the ineffectiveness of their standard methods, have resorted to more extreme measures: yesterday, eight activists chained themselves to equipment at a construction site for an already approved portion of the project.
The main issue environmentalists have with the pipeline (and the main benefit claimed by its proponents) is its potential to encourage the exploitation of Canadian bituminous sands, commonly known as “oil sands” or “tar sands.” Unlike the crude oil of conventional petroleum deposits, the wealth of the tar sands is in the form of bitumen, a heavy substance completely mixed with sand, clay and water, forming a viscous mixture that has been compared to “cold molasses.” The extraction of oil from the tar sands is accomplished either through mining or processes such as steam-assisted gravity drainage, in which steam is used to heat the sands to the point at which they begin to flow and the resulting mixture is pumped out of the ground. Bitumen must be further treated to be sold and used as fuel, a capital-intensive endeavor, and the economic feasibility of tar sand exploitation depends heavily on oil prices. When business is thriving, however, tar sand extraction uses massive quantities of fresh water and natural gas, contaminating aquifers and consuming large amounts of energy.
The environmental impacts of the sands themselves are also a topic of intense debate. A number of scientists have hypothesized that the nature of diluted bitumen makes it more prone to leakage from pipelines, but the most recent report from the independent National Academy of Sciences claims that “[d]iluted bitumen has no greater likelihood of accidental pipeline release than other crude oils.” In comparison with conventional sources of oil, extraction from the tar sands produces approximately 14 percent more greenhouse gases; although these emissions currently account for only 0.15 percent of the global total, the reserves in the sands represent 240 billion metric tons of carbon against the “trillion ton” limit proposed by Myles Allen of Oxford University.
However, the economic benefits of building the pipeline could be considerable: the U.S. Chamber of Commerce predicts that Keystone XL could add 250,000 jobs and $20 billion to the economy over the course of its construction. Stopping the project may even be the worse of two environmental evils, as China represents a significant alternative market for the tar sands, and the emissions standards of that nation are less stringent than those of the United States. There is no easy answer regarding the construction of Keystone XL, but it seems as if the extraction of the tar sands is destined to happen. Building the pipeline could ensure that the exploitation of these resources is handled in the least damaging way possible.