This paper examines the Alberta tar sands, home to the world's second-largest proven petroleum reserve, exploring the science of bitumen extraction, the evolution of production methods, and the significant environmental consequences associated with oil sands development. The paper reviews arguments from both industry proponents and environmental critics, covering topics such as carbon emissions, tailings pond contamination, avian mortality, and water quality along the Athabasca River. Drawing on peer-reviewed sources and government reports, it evaluates whether tar sands oil constitutes a viable long-term energy source and weighs the ecological costs against Canada's growing role as a global petroleum supplier.
The paper exemplifies the use of direct quotation paired with attribution to manage competing claims. Rather than simply asserting that environmental damage is significant or that the industry is responsible, the author quotes specific named researchers, officials, and publications, then juxtaposes their positions — for example, placing the Alberta government's self-reported tailings data directly against Timoney et al.'s scientific estimates. This technique lets evidence speak while maintaining an analytical frame.
The paper opens with a factual introduction establishing the scale of the reserve, then moves through technical sections on extraction science and process evolution. A central "pros" section presents the government and industry perspective, followed by an environmental-impacts section covering water contamination, PAH compounds, and bird mortality. A dedicated viability section synthesizes the competing claims, and a conclusion summarizes the ongoing tension between energy demand and ecological protection.
The tar sands oil reserves in Alberta, Canada, represent the second-largest proven petroleum reserve in the world — right behind the reserves in Saudi Arabia. The Alberta tar sands are located in the vast boreal forest of Canada, just north of Montana. It is estimated that nearly 179 billion barrels of oil are contained in the tar sands, according to Bridget Mintz Testa, writing in the peer-reviewed journal Mechanical Engineering (Testa, 2008). The great volume of crude oil is seen as a positive, reliable source of energy for Canada and other countries that will be importing this oil. However, the extraction, production, and transportation of tar sands oil also represent a number of serious environmental impacts, which are reviewed in this paper.
Notwithstanding the fact that tar sands oil is in plentiful supply, one of the downsides of the equation is that it is not easily extracted, which poses stiff challenges for oil companies unlike those confronted when extracting oil from traditional wells in Texas, Saudi Arabia, or other parts of the world. The crude extracted from the tar sands is a low-grade kind of crude called bitumen, a "black, oily, viscous" substance that naturally occurs as an organic byproduct of "decomposed organic materials" (Hirst, 2013).
Bitumen has been utilized in myriad ways throughout world history. In ancient Egypt, bitumen was used in the mummification process. In prehistory, it was used as "a sealant, as adhesive, as building mortar, as incense," and even for decorative designs on pots and buildings (Hirst, p. 1). Neanderthals used bitumen to fasten ivory shafts to sharp-edged tools at the Hummal archaeological site in ancient Syria, and Native Peoples in the Middle East used bitumen to waterproof their reed canoes (Hirst, p. 1).
Mining and extracting bitumen is a process that includes "scraping the stuff on the surface" (Testa, 31). To get the bitumen out of the ground, the first step is to clear-cut the forest over the site to be exploited. Once the forest is logged, the next step is to scrape away the "rich topsoil" and store it for reuse when needed to fill in previously scraped areas (Testa, 31). After that, workers remove the "overburden — the material that lies atop the oil sands — which are generally less than 70 meters below the surface," though in some cases the oil sands are up to 90 meters below the surface (Testa, 31).
In the past, bitumen was harvested using draglines and bucket-wheels — equipment "the size of multistory buildings" — to dig up the oil sands mixed with clay. Once the oil sands were in the huge buckets, they traveled on "miles-long conveyor belts" to extraction facilities, where they were dumped into huge drums and mixed with "a witch's brew of steam, hot water, and caustic soda, and heated to 80°C (175°F)" (Testa, 31). The overheated water and fierce pressure caused the bitumen to rise to the top while the sand and clay sank to the bottom. That original process was very expensive and energy-intensive, and so the strategy was eventually changed to what is used in Canada today.
The most recently evolving strategy for harvesting bitumen is called "steam-assisted gravity drainage" (SAGD), which, while not yet in full production, is seen as a less environmentally disruptive process. Essentially, two wells are drilled approximately 200 meters deep and separated vertically by about 16 feet. Steam at about 450°F is injected through one of the wells for about six months before the bitumen rises up the other well; within 18 months, Testa reports, the well can be expected to reach peak production (32).
In the meantime, the most efficient current method does not send raw oil sands directly for extraction. Instead, a "tooth crusher known as a feeder-breaker chews them into smaller pieces," and those pieces are sent by conveyor to a "cycle-feeder" — a tub of "swirling water" (Testa, 32). Tumblers using the same hot-water mixture separate the bitumen from the oil sands, but at only about 25°C in most cases. The bitumen is then transported to a refinery where the oil company Syncrude removes the sulfur and adds hydrogen to convert the bitumen "to high-quality, light, sweet crude oil" (Testa, 32).
An article in the journal Chemical Engineering describes the latest method — being tested as of early 2013 — for separating bitumen from tar sand. Instead of steam, propane vapor (a solvent) is injected at about 40°C and 200 pounds per square inch (psi), compared to the roughly 230°C and 300–400 psi required by the SAGD steam process. The solvent condenses on the "cold walls of the vapor chamber and dissolves the bitumen"; the bitumen then "drains with the solvent down to a production well," and a surface facility separates the propane and other gases, including methane, from the bitumen. N-Solv, the company launching this new strategy, estimates that the oil produced is 20% more valuable than SAGD-produced bitumen (Chemical Engineering).
Canada has been planning to expand its tar sands production for many years. As the fifth-leading oil-producing nation in the world, Canada is relying heavily on tar sands oil. An article in the peer-reviewed journal Discover explains that, including both Venezuela and Canada, there are "a stunning 2 trillion barrels of sand oil reserves," though only about one-tenth of those resources are "recoverable with current technology" (Heger, 2010, p. 2).
The ongoing production of tar sands oil is providing Canada and other countries with much-needed crude oil, albeit there are environmental consequences that accompany the extraction, production, and transportation of this controversial resource. Clearly there is a vital global need for petroleum products, and the Canadians are aggressively marketing their tar sands oil. From an ecological and environmental standpoint, several sources cited in this paper point to negative impacts caused not only by the production process itself, but also because the tailings ponds attract migratory birds. Moreover, the seepage from these tailings ponds — documented by Austen in The New York Times — may be leaking PAHs and other toxic chemicals downstream into other bodies of water.
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