Keystone XL workers laying pipe across the Canada-U.S. border. CALGARY – TC Energy Corp. says it has restarted the section of the Keystone pipeline that was unaffected by last week’s oil leak in Kansas. The Calgary-based company says the restarted segment of pipeline extends from Hardisty, Alta., to Patoka, Ill. The portion of the pipeline affected by the spill remains shut down. The Keystone pipeline suffered the worst leak in its history last week when about 14,000 barrels of oil spilled into a creek in Washington County, Kan. The affected segment of pipeline remains shut down and crews are on scene working on cleanup efforts. The company has said it will be conducting a full investigation, in co-operation with regulators, into the cause of the spill.