Total said natural gas leaked from its Elgin complex off Scotland last March. A dynamic kill operation stopped the leak by May. Gas leaked at a rate 7 million cubic feet per day at its peak.
The company said Monday that operations to restart production began last week after approval from the British government. Total said it expected to reach 50 percent capacity of 70,000 barrels of oil equivalent per day soon.
Last year, the company said the field wouldn't reach full production of 140,000 barrels of oil equivalent until 2015. It said Monday it was launching a redevelopment plan at the offshore project to meet that objective.
Total said its investigation into the incident found the leak was caused by a type of stress corrosion.
Yves-Louis Darricarrere, president of upstream operations at Total, said, "Managing this industrial incident securely for our personnel and with limited impact on the environment was our priority."
Elgin accounted for about 9 percent of the Scotland's oil and natural gas production before last year's incident.