A U.S.regulator's preliminary investigation into the biggest oilpipeline spill this year has raised a red flag that couldtrigger an extensive and costly inspection of tens of thousandsof miles of underground energy lines.
The clean-up of an oil spill from TransCanada Corp's Keystone pipeline may last several weeks, South Dakota's environmental regulator said on Wednesday, but it is still unclear when the key artery will restart.
Opponents of TransCanada's Keystone XL pipeline have launched a last-minute public relations blitz before Nebraska regulators weigh in on its route next week in the last big regulatory hurdle for the long-delayed project.
