Enbridge Inc. says a pipeline that leaked a small amount of crude oil  in the Northwest Territories last week has been restarted.

About four barrels of oil had leaked from the company's Norman Wells pipeline, located 50 kilometres south of Wrigley, N.W.T., around May 9.

The repaired pipeline was safely restarted on Friday, Enbridge spokesperson Gina Jordan told CBC News.

However, the company "will not be able to resume full operations until the Plains Midstream line has been restarted," Jordan stated in an email.

Plains Midstream Canada's Rainbow pipeline leaked bout 28,000 barrels of crude  — about 4.5 million litres — into a remote area 100 kilometres northeast of Peace River, Alta., earlier this month.

The Rainbow pipeline break was repaired and the company was seeking permission from Alberta's Energy Resources Conservation Board to restart the line.

But the ERCB first wants the Plains Midstream Canada to dig up and inspect other sections  of the line to determine the integrity of the pipeline.

Over at the Norman Wells pipeline, about 25 people are on site to recover crude oil and conduct environmental reclamation, Jordan said.

"Cleanup is progressing well and we are working on a long-term reclamation plan," she said.

Jordan said the cause of the pipeline spill "remains unknown and is under investigation."