Associated Press: A federal report concludes there would be limited impact to the environment if the TransCanada Keystone XL oil pipeline is built and operated according to existing regulations and the company’s written plan. The buried 36-inch-diameter pipeline across six states would carry crude oil from tar sands near Hardisty, Alberta to refineries in Oklahoma and Texas. The draft environmental impact statement issued by the U.S. State Department will be subject to a 45-day comment period …