The environmental impact of the tar sands developments in Canada has been devastating. Some tar sands (also called oil sands) are located beneath the boreal forests of Canada
There are two methods of extracting the oil:
Surface mining is used when the bitumen is close to the surface and involves clear-felling the forest.
In situ mining involves drilling for the bitumen and pumping it to the surface. Though it looks less dramatically environmentally catastrophic, this still destroys habitats and ecosystems, as bitumen rises to the surface, resulting in toxic pollution that kills off wildlife.
One of the waste products of tar sand extraction is an extremely toxic liquid. This is contained in toxic lakes known as 'tailing ponds' that are up to 50 km2 and can be seen from space.
There is no plan about how to deal with them.
They are deadly to fish and animals.
In a single incident in 2008, a flock of 1600 migratory birds died after landing on one. This figure was initially said to be 500, but the company responsible, Syncrude, admitted during a court case a year later that it was triple the number first reported.
Mutated fish have been found downstream.
Tar sands extraction is extremely water intensive and has worrying implications for the water table in Alberta.
The infrastructure required to support the development of the tar sands includes roads, pipelines stretching to the gulf of Mexico and refining plants. These all have environmental impacts.
Licences for tar sand extraction require companies to return the forest to the condition it was prior to the oil extraction, but most companies admit that this is impossible.(2)