Keystone Pipeline shut down after spilling nearly 800,000 litres of oil in U.S.

TransCanada Corp. says its Keystone pipeline has leaked an estimated 795,000 litres of oil in Marshall County, S.D.

The company says its crews shut down part of the pipeline early Thursday morning after detecting a drop in pressure and are assessing the situation.

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The leak comes only days before Nebraska’s Public Service Commission is set to vote on whether to allow the company to proceed with its Keystone XL pipeline for the last major regulatory hurdle for the $8 billion project. TransCanada has not given a reason for the incident.

Opponents of Keystone XL say the pipeline would pass through the Sandhills, an ecologically fragile region of grass-covered sand dunes, and would cross the land of farmers and ranchers who don’t want it.

The pipeline from Hardisty, Alberta, to Cushing, Oklahoma, and to Wood River and Patoka in Illinois, has been shut, while the southern leg of the system to the Gulf Coast remains operational, the company said.

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The existing Keystone pipeline system that has leaked about 5,000 barrels of oil runs 4,324 kilometres between Hardisty, Alta., and the U.S. Mideast and Gulf Coast.