Oil leak, first discovered by a landowner on Sept. 29 in a low-lying hilltop nine miles northeast of Tioga, North Dakota, is not an immediate threat to groundwater sources, Kris Roberts, who leads the environmental response team at North Dakota State Department of Health, told Reuters.
But, at an estimated 20,600 barrels (Reuters News Agency), the spill ranks among the biggest in the US in recent years.
Per Reuters – San Antonio, Texas-based Tesoro Logistics said the leak occurred on a small, 6-inch diameter pipeline that was carrying Bakken oil to the Stampede rail facility, outside Columbus, North Dakota. The line is part of the company’s “High Plains” pipeline system in North Dakota and Montana, which gathers oil from the Bakken shale and delivers it to another Enbridge pipeline and Tesoro’s 68,000 bpd Mandan refinery in North Dakota.
Per Reuters – it was not clear what caused the spill or how long it lasted, according to Tesoro and the state regulators. Tesoro had initially reported that 1,000 barrels of oil leaked from the pipeline.
Here is the USEPA webpage identifying the oil spill reporting requirements.
Per Reuters – the leak was isolated in an immediate 7.3-acres area of the spill and within the top 10 feet of clay soil, according to a report filed with the National Response Center on Oct. 8.
Per Reuters – such reports are publicly available on the National Response Center website within 24 hours of their filing but the services were interrupted last week because of the U.S. government shutdown.
Thank you to Reuters for reporting this.