The Petroleum Safety Authority Norway has decided to conduct an investigation into an oil spill which occurred on the Statfjord field on Thursday October 08.

A report was received at 08.30 on this day that oil had been observed on the sea close to the OLS B loading buoy on the field, PSA said.

The discovery was made while loading crude from Statfjord A into the Hilda Knutsen shuttle tanker via the buoy, which stands between the A and B platforms.

According to a preliminary assessment by operator Statoil, the spill could be in the order of 40 cubic metres of crude oil.

The PSA has resolved to investigate this incident, in part to clarify the course of events and to identify the direct and underlying causes.

Issues due to be covered will include the technical condition, maintenance and operation of the offshore loading system, PSA informed.

The Norwegian share of the Statfjord field lies in blocks 33/9 and 33/12 in production licence 037, while the British part is in UK block 211/25 in licences 104 and 293.

The field will remain in production until 2025 with possibilities to further expand the lifetime.