Environmental Engineering Reference
In-Depth Information
refineries in Edmonton, the synthetic crude or bitumen is moved by one of several pipelines
to the United States (see figure 7). The Athabasca pipeline has capacity of 570,000 barrels per
day (b/d) while the Corridor has capacity of less than 200,000 b/d. Current pipeline capacity
has nearly reached its limit. However, there are plans to increase Corridor's capacity to
610,000 b/d by 2010.
A number of new pipeline projects have been proposed or initiated that would increase
the flow of oil from Canada to the United State's PADDs II, III, and V. Most of the new
projects are scheduled to come online between 2008 and 2012. In addition, a couple of U.S.
pipelines reversed their flow of crude oil (from south to north) to now carry Canadian heavy
crude, originating from oil sands, to Cushing Oklahoma and Southeast Texas. Pipeline
capacity could be a constraint to growth in the near term but the NEB predicts some excess
pipeline capacity by 2009. An estimated $31.7 billion has been invested in pipeline projects
for oil sands in western Canada.[62]
Environmental and Social Issues
The Federal Government of Canada classified the oil sands industry as a large industrial
air pollution emitter (i.e., emitting over 8,000 tons CO2/year) and expects it to produce half of
Canada's growth in greenhouse gas (GHG) emissions[63] (about 8% total GHG emissions)
by 2010. The oil sands industry has reduced its “emission intensity” by 29% between 1995-
2004 while production was rising. CO2 emissions have declined from 0.14 tons/bbl to about
0.08 tons/bbl or about 88 megatons since 1990.[64] Alberta's GHG goals of 238 megatons of
CO2 in 2010, and 218 megatons CO2 in 2020 are not expected to be met.[65] Reducing air
emissions is one of the most serious challenges facing the oil sands industry. However,
according to the Pembina Institute, a sustainable energy advocate, greenhouse gas emissions
intensity (CO2/barrel) from oil sands is three times as high as that from conventional oil
production.[66] The industry believes if it can reduce energy use it can reduce its emissions.
As emissions per barrel of oil from oil sands decline overall, the Canadian government
projects that total GHG emissions will continue to rise through 2020, attributing much of the
increase to increased oil sands production.[67]
Water supply and waste water disposal are among the most serious concerns because of
heavy use of water to extract bitumen from the sands. For an oil sands mining operation,
about 2-3 barrels of water are used from the Athabasca river for each barrel of bitumen
produced; but when recycled produced water is included, 0.5 barrels of “make-up” water is
required, according to the Alberta Department of Energy. Oil sands projects currently divert
150 million cubic meters of water annually from the Athabasca River but are approved to use
up to 350 million cubic meters.[68] Concerns, however, arise over the inadequate flow of the
river to maintain a healthy ecosystem and meet future needs of the oil sands industry.
Additionally, mining operations impact freshwater aquifers by drawing down water to
prevent pit flooding.
The freshwater used for in-situ operations is needed to generate steam, separate bitumen
from the sand, hydrotransport the bitumen slurry, and upgrade the bitumen to a light crude.
For SAGD operations, 90-95% of all the water used is recycled. Since some water is lost in
the treatment process, additional freshwater is needed. To minimize the use of new freshwater
supplies, SAGD operators use saline water from deeper underground aquifers. The use of
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