By MarEx 2015-08-20 17:27:55
The Petroleum Safety Authority of Norway has completed its investigation into two incidents which occurred on the Eldfisk complex on August 6-8, 2014, and written a “please explain” letter to ConocoPhillips.
The highest emergency shutdown level (yellow ESD – abandon platform) was initiated on the Eldfisk complex and Embla on the morning of August 6. This caused total loss of power and all systems shut down on the Eldfisk A, Eldfisk FTP and Embla installations, while Eldfisk E lost main power.
The ESD was unplanned. Its direct cause was the technical failure of an electronic component combined with a design error.
When restarting production after the ESD, a blowdown valve remained in the open position. It should have been reset to the closed position as part of the start-up procedure. That caused produced oil to flow into the flare system, on into the drain system and from there to the sea.
At dawn on August 7, oil was observed on the sea. Production was not shut down until 13.30 on August 7, since the size of the oil slick was increasing. The oil spill is estimated to have been in the order of 50-70 cubic meters.
The PSA’s investigation of the incident has identified several breaches of the regulations of a technical and operational character. Some of the technical nonconformities relate to Eldfisk FTP’s condition at the time of the incident.
Eleven non-conformities were identified by the investigation. These relate to:
• risk management during start-up of production after the emergency shutdown
• off-duty periods
• safety clearance when restarting production
• robustness against single errors and faults in safety systems
• verification of design requirements for the safety systems before start-up and
• lack of independence between control and shutdown functions for level measurement
• barrier management, risk assessments and analyses in connection with modifications
• updating of documentation in connection with modifications
• consequence classification of systems and equipment
• maintenance program for the drain system.
Two improvement points were also identified:
• performance requirements for emergency response
• training and drills.
The facility has subsequently been shut down and now functions primarily as a bridge support.
The PSA has written and asked the operator ConocoPhillips to describe how it intends to deal with the nonconformities. ConocoPhillips has until September 15 to respond.
The full investigation report is available here.