The latest incident occurred last week at the ConocoPhillips-operatedEldfisk FTP field terminal, leading to a discharge of stabilized oil to the sea.
At the time the installation was in the process of starting up after an emergency shutdown and loss of power on Aug. 6.
According toConocoPhillips, a blowdown valve in the separator was left open during the start-up, with oil escaping via a sea sump and knockout drum.
The leak was discovered and halted at 5 a.m. on Aug. 7. A helicopter was sent to monitor and assess the size of the spill, and mechanical recovery of the oil was started.
PSA says its inquiry will look to determine the course of events, and identify the direct and underlying causes.