August 16, 2011

comment on oil spill in the North Sea

A leak from a flowline to the Shell-operated Gannet Alpha platform caused the biggest oil spill in the North Sea for a decade.

Dr Simon Boxall, an oceanographer at the University of Southampton, said:

“The spill occuring in the North Sea froom a pipeline from Gannet Alpha, about 180km from the Scottish coast, has so far released around 200-250 tonnes of light crude (c.1300-1600 barrels). In terms of scale this is a small spill, only 10% of the platform’s daily production over the past 4-5 days and a fraction of the estimated 585,000 tonnes spilt from Deep Water Horizon in the Gulf of Mexico. As with the Gulf spill the oil is natural crude which will break down relatively quickly through microbial action and it is a fair distance from shore so the probability of landfall is slight at this stage. This is further helped by the moderate to strong winds pushing the oil further into the northern parts of the North Sea.

“So should we be concerned? Any spill is harmful to the environment in some way and whilst this is not a major incident it will cause some damage. More critically in the cooler waters of the North Sea microbial action takes longer and so the oil remains harmful for longer as well. The big problem in the Gulf was the depth of the incident – 1500m. In the North Sea the depths are less than a tenth of this and the technology far more straightforward. However, the strong winds pushing oil away from the coast of Scotland are also hampering efforts to block the leak and it is nature rather than technology that hampers work on the leak. In winter it is not unusual to have weeks where any operations of this type would be dangerous and ill-advised.

“Royal Dutch Shell, the operators, and their co-operators on the platform Esso, are amognst a number of companies keen to extract oil from deeper sources to the North west of Shetland. This oil is needed if North West Europe is to maintain its own oil and gas supplies, but it carries the dangers of deep water ina cold and stormy climate – the worst of both worlds. After BP’s experience in the Gulf of Mexico, and in spite of it, many other oil companies were reticent to see significant changes to safe practices in other parts of the World. Whilst this is an unusual event, the North Sea Platforms do have a relatively good safety record, it does highlight the problems ahead.”