Initial investigations following a 20,600-barrel leak on Tesoro Logistics LP pipeline in North Dakota point to corrosion on the 20-year-old pipeline, state regulators said Nov. 11, Reuters reported.
The 6-inch pipeline was carrying crude oil from the Bakken Shale to the Stampede rail facility outside Columbus, ND when a farmer discovered oil spouting from the pipeline on Sept. 29. This is the largest oil spill in the state since it became a major U.S. producer.
The release did not pose an immediate threat to groundwater sources or nearby rivers and lakes, the state Department of Health said. Initial concerns that the pipeline was damage by nearby residents were dismissed and the cause appears to be corrosion on the pipeline, said Brian Kalk, chairman of the state Public Service Commission.