Statoil (NYSE:STO) reported that at 03.25 on Thursday morning a well incident was detected on the exploration rig Deepsea Atlantic.
The well has been closed for seven days owing to bad weather conditions on the field. Normal procedures are followed after such an incident to ascertain any possible seepage in the well.
When the blow-out preventer (BOP) was opened after the closure and mud circulated, gas was registered in the mud processing unit on the platform. The well control system was then immediately closed down in line with procedures.
The gas in the well was circulated in a controlled manner and both well barriers were re-established.
The incident led to the crew being mustered on board in accordance with regulations. Normalisation efforts on the rig commenced a half-hour later and the situation was quickly clarified. Work on the well has now been resumed.
The incident was reported to the Petroleum Safety Authority Norway.
Statoil will closely examine the incident and is dispatching its own personnel, and personnel from drilling operator Odfjell Drilling, to conduct investigations. The team will also determine the final classification of the incident.
Deepsea Atlantic is exploring for Statoil on the Gullfaks South field, where it is about to complete operations in connection with the gas and condensate discovery in well 34/10-53. This constitutes an independent exploration prospect unconnected to the main reservoir on the Gullfaks field.
The well was drilled using conventional drilling technology in an area where there are not the same demanding reservoir and pressure conditions as on the main Gullfaks field. Pressure conditions during this drilling operation were in accordance with the calculations made in advance.