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The Harm the Tar Sands Will Do

The project's expected costs to our forests, water and air.

Dan Woynillowicz 20 Sep 2007World Watch/

Dan Woynillowicz is a senior policy analyst with the Pembina Institute, based in Calgary, Alberta. This article was distributed by

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Oil sands open pit mining in Alberta's Athabasca region.

The environmental consequences of oil production from Alberta's tar sands are major, beginning with its effect on climate change. North America's transition to oil from the tar sands not only perpetuates, but actually worsens, emissions of greenhouse gas pollution from oil consumption.

While the end products from conventional oil and tar sands are the same (mostly transportation fuels), producing a barrel of synthetic crude oil from the tar sands releases up to three times more greenhouse gas pollution than conventional oil. This is a result of the huge amount of energy (primarily from burning natural gas) required to generate the heat needed to extract bitumen from the tar sands and upgrade it into synthetic crude. The energy equivalent of one barrel of oil is required to produce just three barrels of oil from the tar sands.


In 2002, the Canadian government ratified the Kyoto Protocol on global warming, legally committing to a target of reducing the country's greenhouse gas pollution by six per cent below 1990 levels by 2012. But oil industry lobbying and the rapid growth of tar sands development have undermined efforts to reduce greenhouse gas pollution for over a decade.

Since 1990, Canada's total emissions have risen 25.3 per cent, a pace far exceeding the 16.3 per cent increase in the United States, the second-fastest-rising nation, according to United Nations data. Regulations introduced in early 2007 are so fraught with loopholes and gaps that greenhouse gas pollution from tar sands is predicted to triple by 2020. Canada's greenhouse gas emissions in 2020 are projected to be two per cent above 1990 levels. The environmental consequences of tar sands development hardly stop with climate change. Nowhere in the world is there a form of oil extraction and processing with more intense impacts on forests and wildlife, freshwater resources and air quality.


The tar sands are found beneath boreal forest, a complex ecosystem that comprises a unique mosaic of forest, wetlands and lakes. Canada's boreal forest is globally significant, representing one-quarter of the world's remaining intact forests. Beyond the ecosystem services it provides (cleansing water, producing oxygen and storing carbon), it is home to a wide variety of wildlife, including bears, wolves, lynx and some of the largest populations of woodland caribou left in the world. Its wetlands and lakes provide critical habitat for 30 per cent of North America's songbirds and 40 per cent of its waterfowl.

If currently planned tar sands development projects unfold as expected, approximately 3,000 square kilometres of boreal forest could be cleared, drained and strip-mined to access tar sands deposits close to the surface, while the remaining 137,000 square kilometres could be fragmented into a spider's web of seismic lines, roads, pipelines and well pads from in situ drilling projects. Studies suggest that this scale of industrial development could push the boreal ecosystem over its ecological tipping point, leading to irreversible ecological damage and loss of biodiversity.

'Staggering challenges'

Satellite images readily illustrate the magnitude of boreal forest impacts from tar sands mining operations. The United Nations Environment Program has identified Alberta's tar sands mines as one of 100 key global "hotspots" of environmental degradation. According to Environment Canada, development of the tar sands presents "staggering challenges for forest conservation and reclamation."

Very little of the area directly affected by mining operations has been reclaimed, and after 40 years of mining, not a single operation has received a reclamation certificate from the government of Alberta. Suncor Energy's operation, the longest-operating tar sands mine, says it has reclaimed 858 hectares of land since starting operations in 1967, less than nine per cent of the land its operations have disturbed to date. Syncrude Canada, the largest daily producer of tar sands, says its operations have disturbed 18,653 hectares since 1978, with just 4,055 hectares of land reclaimed. None of this reclaimed land has been certified as such. At best, reclamation of the tar sands region will be a large-scale experiment that is unlikely to restore a self-sustaining boreal forest ecosystem within the next century.


The Athabasca River winds nearly 1,500 kilometres from its source at the Athabasca Glacier in Jasper National Park to Lake Athabasca in Wood Buffalo National Park. It is Alberta's longest river and one of North America's longest undammed rivers. It enters Lake Athabasca at the Peace-Athabasca Delta, the largest boreal delta in the world, a World Heritage Site, and one of the most important waterfowl nesting and staging areas in North America.

It also passes directly through the boreal forest being cleared and strip-mined, and serves as the primary source of water used to separate the bitumen from the mined tar sands. Water withdrawals for tar sands surface mining operations pose threats to both the sustainability of fish populations in the Athabasca River and to the sustainability of the Peace-Athabasca Delta, jeopardizing the subsistence and commercial fisheries of local aboriginals.

Tar sands mining operations withdraw two to 4.5 barrels of fresh water from the river for every barrel of oil they produce. Current operations are permitted to withdraw more than 349 million cubic metres of water per year, a volume equivalent to the amount required by a city of two million people. But unlike city effluent waters, which are treated and released back into the river, tar sands mining effluent becomes so contaminated that it must be impounded.

No stopper on the drain

Historically it was believed that the Athabasca River had sufficient water flows to meet the needs of tar sands operations. But it is becoming clearer that this might not be the case, particularly during the winter months, when river flows are naturally lower, and growing demand for water withdrawals could lead to long-term ecological impacts. The sustainability of fish populations in the Athabasca River is threatened by continuous tar sands water withdrawals during the winter months in years when low precipitation rates in the Athabasca River basin lead to low flow conditions. Nonetheless, the government has failed to implement regulations that would require tar sands withdrawals to stop when the health of the river is at risk. In fact, the government explicitly allows the tar sands industry to continue withdrawing water no matter how low the river flows become.

For certain in situ drilling operations, significant amounts of water are required to create steam to be injected underground. Because the steam condenses into water and is pumped up with the bitumen, the water can be recycled. However, because some water remains underground, a continuous source of additional water (about half a barrel of water per barrel of bitumen) is required.

These operations are located much farther from the river and, as a result, rely mainly upon groundwater. Where shallower freshwater aquifers are used, the continuous pumping of water can lower the water table in the region. Because these groundwater aquifers are connected to lakes, rivers and wetlands, reducing their levels can cause lakes to shrink and wetlands to dry out. As a result, some operators have switched to deeper sources of salty groundwater. But because they require fresh water, the salty water must be treated, which produces large amounts of waste sludge that must be disposed of.

Vast reservoirs of waste

Both tar sands mining and in situ operations produce large volumes of waste as a result of their water use. For in situ operations, the primary waste stream, a result of treating salt water and the water that is pumped up with the bitumen, is disposed of in landfills or injected underground. Tar sands mining operations present a much more significant risk, because they produce large volumes of waste in the form of mine tailings (six barrels of tailings per barrel of bitumen extracted). These tailings, a slurry of water, sand, fine clay and residual bitumen, are stored in vast wastewater reservoirs.

The industry misleadingly refers to them as "tailings ponds," but collectively these pools of waste cover more than 50 square kilometres and are so extensive that they can be seen from space. One tailings pond at Syncrude's mining operation is held in check by the third-largest dam in the world. These tailings dumps pose an environmental threat resulting from the migration of pollutants through the groundwater system and the risk of leaks to the surrounding soil and surface water.

The high concentrations of pollutants such as naphthenic acids, which are found at concentrations 100 times greater than in the natural environment, are acutely toxic to aquatic life, yet the government has no water-quality regulations for these substances. Migratory birds fare slightly better: to prevent them from landing, propane cannon go off at random intervals and scarecrows stand guard on floating barrels. How this tailings waste, and its grave risks, might be dealt with in the long term remains unknown.


Tar sands air pollution, both provincial and transboundary, is rapidly increasing. Since 2003, Alberta has been the industrial air pollution capital of Canada. Criteria Air Contaminants (CACs) are the most common air pollutants released by heavy industry burning fossil fuels. CACs are defined as "air pollutants that affect our health and contribute to air pollution problems" and include such things as nitrogen oxides (NOX), sulphur dioxide (SO2), volatile organic compounds and particulate matter, all of which are emitted in large volumes by tar sands operations.

Modelling of the impacts of approved tar sands development, which includes three operating mines and three operations at various stages of planning and construction, shows that maximum predicted ambient air concentrations of NOX and SO2 would exceed provincial, national and international guidelines. Emissions of volatile organic compounds such as benzene are also on the rise because of both emissions from burning fossil fuels (e.g., natural gas, diesel, coke) and the growing number of tailings ponds. The costs of such air pollution have not been considered.

Tomorrow, Part II: The U.S. push to develop the tar sands as "a pillar of sustained North American energy and economic security."

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