(Adds Canadian Natural comments, details)
By Devika Krishna Kumar
NEW YORK, Nov 7 (Reuters) - TC Energy Corp estimates the Keystone oil pipeline can be partially restarted anytime from Sunday to Tuesday, pending regulatory approval, after a more than 9,000-barrel leak in rural North Dakota, shippers on the line said on Thursday.
Crews in Walsh County, North Dakota, have been working to clean up the spill from the Keystone pipeline, which forced the line to be shut last week.
The 590,000-barrel-per-day Keystone system is an important artery for Canadian heavy crude, imported by U.S. refiners, particularly in the Midwest.
There is no timing yet on when the system will return to service, TC Energy spokesman Terry Cunha said in an email.
TC Energy’s estimated restart time line does not yet have regulatory approval from the U.S. Pipeline and Hazardous Materials Safety Administration (PHMSA), two sources familiar with the matter said.
The outage has already backed up barrels in Canada, sending the discount on Canadian heavy crude versus U.S. benchmark West Texas Intermediate (WTI) crude to an 11-month high on Thursday.
Repairs are likely to be completed by Sunday, which will allow the company to be prepared for a restart, one shipper said.
Analysts have said they expected Keystone to be offline for 10 to 12 days and be online by Sunday.
TC Energy, former TransCanada Corp, said previously that the preliminary work to expose and extract the damaged section of pipe was expected to be completed by the end of this week.
The pipeline may return to service within a couple of weeks, based on past spills, the president of Canadian Natural Resources Ltd, the country’s biggest oil producer, said on a quarterly earnings call on Thursday.
The outage has had “very little impact” on Canadian Natural, a shipper on the pipeline.
Reporting by Devika Krishna Kumar in New York; Editing by Sandra Maler and Peter Cooney