Wednesday, March 26, 2014

Oil Sands: Canada's "shale" controversy


Just as the extraction of shale gas is a controversial issue in the United States, the same is true of oil sands (also known as tar sands) are in Canada.  Both are considered unconventional sources of fossil fuel energy. As mentioned in yesterday’s blog, the major oil sands in Canada (also the largest in the world) are located in Alberta, a province located just north of Montana.

The proposed Keystone XL Pipeline
Imperial Oil Sands Project:
1 year of operation
Source: Doug Vine Twitter Feed
would transport oil extracted from this resource (see picture below) from Canada to Gulf Coast of the United States.

 The two sites that we visited as part of the Pan-Prairie tour illustrated the two ways oil sands are extracted: mining (the older traditional technology) and in-situ drilling (a new technology using a combination of horizontal drilling and “steam assisted gravity drainage”).  Reaching both from Edmonton required a plane ride (about an hour) or it would have been a long drive (about the time it takes to get from Pittsburgh to Philadelphia.)  See

The mining site we visited was managed by Suncor.  As we drove through the “boom” town of Fort McMurray, I was struck by how much this town faced the same challenges as the smaller boom towns in Pennsylvania.  Fort McMurray had its initial boom when mining began in the 1960s.  The population has boomed again as Fort McMurray serves as a base for oil sand extraction using both technologies throughout the region.  The population in the town is about 77,000 and for the municipality (what we would call a county, it is about 104,000).  In 1951, the population was about 1,000; 1971 about 7,000; and 2001 about 39,000. 

Reclaimed Site
Source: Marcus Thibalt Twitter Feed
The Suncor site itself is vast and faces all the challenges of surface mining.  In particular, the loss of habitat for wildlife on both land and water as well as concerns about the impact of hazardous materials on air, land, and water.  Because the oil sands in this area are close to the surface they can be extracted using large shovels in an open pit mind with the oil sands then loaded into tremendously large trucks for processing.  The oil sands are then crushed and processed so that they can eventually enter a pipeline as heavy oil.  Besides the impact on the land, “tailings ponds” are created for the waste products (commonly known as “settling ponds” in the U.S.).  There are about 77 square kilometers of tailings ponds in Alberta.  At one time, the life span for these tailings ponds was expected to be about 40 years; today it is more on the order of 10 years.  The goal for both the land and the ponds is reclamation – after the resources are extracted restoring them to their natural state.  During the tour, we were shown several sites where reclamation had occurred.  Although the land is reclaimed, the wildlife  In addition, there are concerns that the tailing ponds leak.  An overview of the environmental issues is provided by Pembina – the nongovernmental organization to whom we spoke on the previous day.  And a Royal Society of Canada (analogous to the US National Academy of Sciences) report outlines questions they have as of 2010.

Oil Processing
Source: Marcus Thibalt Twitter Feed
When we visited the MEG Energy Christina Lake In-Situ Drilling site, the site was much, much smaller than the mining site and its environmental footprint appeared to be less.  In addition, the impact appeared to be less than hydraulic fracturing.  Steam is generated using off-the-shelf cogeneration technology.  The steam is then injected down a horizontal pipeline to heat the oil sands which then enter a second pipeline to bring the oil to the surface so it an eventually enter the pipeline network.  A third pipeline goes between the other two pipelines to extract additional oil which enhances the efficiency of the process.    Unlike surface mining, the land disturbance (at least above ground) is less and there are no tailings ponds. And unlike hydraulic fracturing, the steam that enters the pipeline is not at high pressure, so there appears to be less impact below ground.  Overall, less waste also appears to be generated so there are no tailings ponds created for in-situ drilling, and the amount of wastewater
generated seems to be less of a concern than for hydraulic fracturing.

The good news perhaps is that while 20% of Canada’s oil sands reserves can be extracted using surface mining, 80% of the reserves would be extracted via in-situ drilling.  This assessment of Pembina compares the environmental impact of the two. 
Source: Pembina

The bottom-line:  Not all oil sands extraction is alike and this nuance needs to be considered in public policy-making both in Canada and the United States.  Personally, I would like to see some calculations that really make a true assessment of both processes in terms of their environmental impact relative to traditional oil well processes.  There may well be such an analysis out there but if not I may try to do it myself when I’m back at Carnegie Mellon.  This I think will give, from a public policy standpoint, more guidance to US policy-making.  In addition, my I believe there are lessons that can be shared between Pennsylvania and Canada that would increase both environmental protection and public confidence.  I’ll discuss more on this issue in my next blog.



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