|Section of Silvertip Pipeline|
The leak from the 12-inch pipeline caused the temporary evacuation of some area residents. Local officials have said that flooding has hampered the cleanup work, and that some of the leaked oil could reach the Missouri River, of which the Yellowstone is a tributary.
People near the area with acute hydrocarbon exposure are experiencing dizziness, nausea and trouble breathing. The Environmental Protection Agency is still taking air and water samples to determine the impacts. The cause of the Montana spill has not yet been determined. Company and government officials have speculated that high waters in recent weeks may have scoured the river bottom and exposed the pipeline to debris that could have damaged the pipe.
More than 280 people were involved in the response and cleanup and more than 9 miles of absorbent booms are being deployed. (Wash Post, 7/4/2011, NY Post, 7/4/2011))