Crude oil from Canada’s tar sands is known to be one of the dirtier and more costly to process crude varieties, a fact that has been a major stumbling block in the construction of

The proposed XL leg of the Keystone Pipeline, the controversial oil-supply conduit that would funnel Canadian tar sands oil through the Upper Midwest to shipping centers in Oklahoma, is facing

 President Obama has been wavering on the proposed Keystone XL extension that would complete the Keystone Oil Pipeline. In a Tuesday speech, the President said “our national interest will