The protesters outside the White House have furled their banners and headed home. Now the Obama administration will decide whether to issue a presidential permit for the 1,700-mile Keystone XL pipeline extension – a $7 billion project to bring heavy, “sour” crude oil extracted from tar sands in Alberta, Canada, down through Montana and the Plains states to refineries on the Gulf Coast, notably in Port Arthur, Texas. - IV440 - September 2011 / USA, Ecology and the Environment