Montana’s Yellowstone River was the victim of a crude oil spill when an ExxonMobile pipeline that was under the riverbed ruptured. The many barrels that spilled into the river forced evacuations and sent a plume twenty five miles downstream. The break was in south central Montana near Billings. This break forced irrigation and municipalities to close intakes and fouled the riverbank.
They are not sure just how far this plume might travel because there are no dams to confluence with the Missouri River, which is just across the border in North Dakota. As it moved down the river at five to seven mph, cleanup crews deployed absorbent material and booms. It is estimated that between seven hundred fifty to one thousand barrels of crude oil, which is equal to approximately forty two thousand gallons, leaked into the Yellowstone River before they shut it down,
One thing that is hampering the cleanup of the crude oil spill is that the Yellowstone River is moving at flood stage with a lot of debris in the river. In the Laurel area approximately one hundred forty people were temporarily evacuated on Saturday because they feared they may be explosions and there were also overpowering fumes.
At this time they do not know what caused the pipe to rupture because with the Yellowstone River at flood stage, the bank is not stable enough for anyone to get close enough. They think it may have been caused by the high water gouging out the river bank, which exposed the pipe and it was hit by some debris in the river. The pipe that was carrying the crude oil was twelve inches in diameter and was buried 6 feet below the riverbed. Where the leak happened the Yellowstone River was about two hundred fifty yards wide and the oil slick was approximately twenty feet wide.