New research in Proceedings of the National Academy of Sciences has examined the impact of tar sands mining in Canada on boreal forest and peatlands, finding that contrary to industry claims that such landscape can be restored post-mining, full restoration is not possible.
Furthermore, due to the fact that currently approved mines will cause the destruction of more than 29,500 hectares (114 square miles) of peatland, an additional 11.4-47.3 million metric tons of carbon emissions will be released by the mining. The destruction of the peat swamps will also remove carbon storage potential of up 7,200 metric tons per year, even after restoration is done.
The release of these greenhouse gases has never previously been included in calculations of the life-cycle emissions of fuel produced from tar sands.
The scientists write:
Constraints imposed by the post-mining landscape and the sensitivity of peatland vegetation prevent the restoration of peatlands that dominated the pre-mining landscape.
Claims by the industry that they will "return the land we use—including reclaiming tailing 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.
In areas that are reclaimed, the report says, it is unlikely that the peat swamps will ever be able to reestablish themselves, with 67% of all the land becoming drained forest, storing far less carbon than peat.