Workers with heavy equipment try to contain an oil spill on the Jensen farm near Tioga, North Dakota on October 12, 2013. A Tesoro Logistics LP pipeline spilled more than 20,000 barrels of crude oil into a North Dakota wheat field, the biggest leak in the state since it became a major U.S. producer. The six-inch pipeline was carrying crude oil from the Bakken shale play to the Stampede rail facility outside Columbus, North Dakota. The spill was originally discovered on September 29, 2013. Photo by Neal Lauron/Greenpeace