The incident occurred in the Statpipe facility where gas pipelines connect to the facility for processing. Both Statpipe production trains have been stopped.
During normalization and startup of the plant following the incident, a smaller leak occurred, which Statoil says is not usual during run-up of plant sections.
The situation is returning to normal and external resources from emergency services have been demobilized, the company says. The incident did not cause any injuries.
Statoil plans to investigate the cause of the leak.