Fairfield Energy Limited has advised DECC that whilst conducting ROV operations at the Osprey subsea manifold, another ongoing small leak has been discovered at one of the 8” oil flowlines downstream of the production manifold. Although the line is depressurised a small amount of oil bubbles are continuing to float to the sea surface.
Fairfield therefore intend to flush the 8” test and production lines with seawater back to the Dunlin installation on Friday 27 July 2012. This is in order to remove all the oil from the pipelines which should stop the oil bubbles floating to the surface. For clarification, Fairfield has to date notified DECC of oil releases from three locations; the P3 well head which is now isolated, the manifold which is now releasing very small amounts of gas and from one of the 8” flowlines. The maximum volume of oil released to sea is to date 13.8 tonnes.
DECC continues to monitor the incident and is in daily contact with Fairfield Energy Limited.
Update: 25 July 2012
Fairfield Energy Limited have advised DECC that they undertook subsea operations on Friday 20 July to isolate the P3 well from the Osprey system and the oil leak identified as coming from the subsea infrastructure in the vicinity of the P3 was stopped. During the isolation operations a secondary small oil leak from the vicinity of the Osprey production manifold was observed. In the period from Friday 20 July to Tuesday 24 July Fairfield have notified DECC that an additional 0.19 tonnes of oil has been released to sea with a small visible surface sheen. This oil sheen has been observed to be dispersing naturally.
Production from the Osprey and Merlin fields has been shut down and the system depressurised. Fairfield have advised DECC that ROV inspections will commence on Wednesday 25 July in an attempt to ascertain the exact location of the small ongoing oil leak to facilitate the necessary repairs.
The total maximum volume of oil released to sea during this incident has been reported to DECC as 11.25 tonnes. This incident presents no risk to personnel. Fairfield have provided DECC with an Environmental Impact Assessment which confirms the oil released to sea will have minimal environmental impact.
DECC continues to monitor this incident.
Update: 16 July 2012
Fairfield Energy Limited has advised DECC that an ROV inspection took place over the weekend and the source of the leak on the Osprey subsea structure has been found. Fairfield are currently sourcing a Diving Support Vessel (DSV) to attend the location so that work can commence to implement the necessary repairs to isolate the subsea structure. The Osprey field is still shut down and depressurised. DECC continues to monitor the situation and can confirm that very small quantities of oil are being released from the subsea manifold to the sea surface, but that this is dispersing quite quickly.
Update: 14 July 2012
DECC can confirm that a hydrocarbon spill was reported in the vicinity of the Osprey subsea manifold that feeds back to the Dunlin Alpha installation at approximately 8.30pm on Tuesday 10 July. The Dunlin Alpha installation, which is located in the North Sea 195km north-east of Shetland, is operated by Fairfield Energy Limited.
The initial report from the operator was that up to 8.7 tonnes of oil had been released to sea and production from the Osprey field was shut down and depressurised. The installation standby vessel remains in the vicinity and aerial surveillance is being routinely undertaken. Visual observations report that there continues to be a very small ongoing release of oil coming to the sea surface but that this dispersing rapidly.
Fairfield are mobilising a vessel with ROV capability to undertake a visual inspection of the manifold and other subsea infrastructure which is expected in the field this weekend.
The spill presents no risk to personnel and will have no impact on the environment.
All relevant authorities and the SOSREP have been notified and DECC continues to monitor this incident.