Nexen Energy, the Canadian subsidiary of Chinese state-owned CNOOC Ltd, is shutting down its Long Lake oil sands operations in response to an emergency regulatory order, a company spokeswoman said on Sept. 1.

Nexen estimated the shutdown process would take up to two weeks as it suspends pipeline operations and attempts to demonstrate to the Alberta Energy Regulator that its pipelines are safe.

The provincial regulator ordered Nexen to shut in 95 pipelines at the Long Lake facility Aug. 28 as part of an ongoing investigation into a large oil-related pipeline spill discovered in July.