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Activists celebrate at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota, after hearing that the Army Corps of Engineers has denied the current route for the Dakota Access pipeline. (JIM WATSON/AFP/Getty Images)

Activists celebrate at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota, after hearing that the Army Corps of Engineers has denied the current route for the Dakota Access pipeline. (JIM WATSON/AFP/Getty Images)

Activists celebrate at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota, after hearing that the Army Corps of Engineers has denied the current route for the Dakota Access pipeline. (JIM WATSON/AFP/Getty Images)