By John Parnell
Estimates of the impact on climate change caused by exploiting Canada’s oil sands must be increased according to a new research paper.
The study looked at the effects of removing thousands of hectares of carbon rich peatland during extraction and replacing them with mining residue lakes (tailings) and forestry.
The paper, published in the US Proceedings of the National Academy of Sciences, estimates that 11.4-47.3 million tons of carbon dioxide will re-enter the atmosphere as a result. The carbon sequestering potential of the new landscape will also be reduced by 5700-7200 tons per year.
The researchers claim that a post-mining landscape will support a minimum of 65% less peatland than originally due largely to the physical and chemical impact of the tailings lakes.
“Claims by industry that they will ‘return the land we use – including reclaiming tailings ponds – to a sustainable landscape that is equal to or better than how we found it’ and that it ‘will be replanted with the same trees and plants and formed into habitat for the same species’ are clearly greenwashing,” the report says quoting media reports and oil industry literature.
Fuel derived from oil and tar sands is already considered by many to be responsible for a higher proportion of carbon emissions than from other sources given the intense industrial processes during extraction. The “heavier” nature of the oil, which makes it harder to burn and with higher pollutant levels, also increases the footprint of the oil.
According to Chevron, two tons of sand is required to extract one barrel of crude oil.
“To fairly evaluate the costs and benefits of oil sands mining in Alberta, impacts on natural capital and ecosystem services must be rigorously assessed,” the researchers say.
The EU has deferred a decision to reclassify oil from tar sands into a “dirtier” category until June.
If successful, the decision would effectively block the sale of tar sands oil in Europe.