Workers took the Keystone oil pipeline offline on Thursday after it spilled 5,000 barrels of oil in rural South Dakota, officials said.



A TransCanada crew shut down the pipeline at 6 a.m. Thursday morning after detecting an oil leak along the line, the company said. The leak was detected along a stretch of the pipeline about 35 miles south of a pumping station in Marshall County, South Dakota.



TransCanada estimates the pipeline leaked 5,000 barrels of oil, or about 210,000 gallons, before going offline. The company said it's working with state regulators and the Pipelines and Hazardous Materials Safety Administration to assess the situation.



The South Dakota Department of Environment and Natural Resources heard about the leak at about 10:30 a.m. Thursday, ABC affiliate KSFY reported.

At approximately 6 a.m. CST (5 a.m. MST) today, we safely shut down the Keystone pipeline after we detected a pressure drop in our operating system resulting from an oil leak that is under investigation.



The estimated volume of the leak is approximately 5,000 barrels. The section of pipe along a right-of-way approximately 35 miles (56 kilometres) south of the Ludden pump station in Marshall County, South Dakota was completely isolated within 15 minutes and emergency response procedures were activated.



The safety of the public and environment are our top priorities and we will continue to provide updates as they become available.

The five members of the Nebraska Public Service Commission will vote on a proposed order for the Keystone XL pipeline on Nov. 20, the agency announced on Monday, though it didn’t detail what that decision might be.



Approval from the Nebraska commission is one of several tasks facing Keystone XL developer TransCanada, which hopes to build the pipeline and deliver oil from Alberta, Canada, to the Gulf of Mexico.



TransCanada reapplied for its Nebraska permit in February, putting the decision in the hands of the Public Service Commission. It applied to follow the same route bisecting Nebraska that the state’s governor approved in 2013, before President Obama rejected federal permits for the pipeline.