"Opponents of the Keystone XL pipeline and the heavy Canadian crude oil that it would carry released two reports on Thursday asserting that the environmental impacts of the project are worse than previously estimated, and urged the Obama administration to veto it."
"One report, from the anti-petroleum group Oil Change International, finds that existing studies of emissions from mining, transporting and refining the oil from oil sands formations in Alberta fails to account for the impact of petroleum coke, or petcoke. The study states that because petcoke is considered a refinery byproduct, its emissions are not included in calculation of the climate impact of exploiting Canadian oil sands.
The study says that the petcoke produced from oil moving through the 1,700-mile Keystone XL pipeline would be equivalent to the coal burned at five conventional power plants.
The second study, from the Canadian environmental research group Pembina, says that construction of the pipeline would bring rapid expansion of tar sands mining and greatly increase overall greenhouse gas emissions."