Shell locates secondary oil leak off Scottish coast
Published 16/08/2011 | 14:22
Shell said today it is working to stop a secondary flow of oil spilling into the North Sea from beneath an offshore platform.
An initial leak was brought "under control" last week but work is continuing on a smaller leak from the same source in an area surrounded by marine growth.
About 216 tonnes of oil - equal to 1,300 barrels - were estimated to have spilled from the Gannet Alpha platform, 112 miles east of Aberdeen, by yesterday.
The amount is far greater than the annual totals for the North Sea over the past decade, according to figures from the Department of Energy and Climate Change.
The total amount of oil discharged into the North Sea in 2009 was 50.93 tonnes.
Environmental groups have heavily criticised the operator for the way it has handled the leak, which was first detected on Wednesday.
Shell said the current rate of leakage is less than five barrels a day.
A Shell spokeswoman said: "The leak source remains the same. The initial release path was stopped on Thursday, however the oil found a second pathway to the sea.
"Since then we have been working to find the source of the much smaller flow of hydrocarbons.
"It had proved difficult to find because we are dealing with a complex subsea infrastructure and the position of the small leak is in an awkward place surrounded by marine growth.
"So it has taken our ROV inspections some time to establish exactly where the source is.
"We believe now that the flow is coming from a relief valve adjacent to the original leak and from the same source.
"Once we've confirmed this we will then develop a series of mitigation options to stop this leak. There is no new leak."
The spill is described as a light crude oil with a low wax content. Hydraulic fluid is also present.
At its peak the sheen on the surface extended 18 miles, but Shell said this has now diminished.
Dr Richard Dixon, director of wildlife organisation WWF Scotland, said: "It is clear that Shell are having great difficulty dealing with their leaking pipeline.
"It really does make you question the entire oil industry's ability to respond had this accident been on a larger scale or in the much more difficult waters of the Arctic."
Per Fischer, of Friends of the Earth Scotland, said: "It beggars belief that we are still being drip-fed information and that Shell's initially 'insignificant' leak is still causing problems."
Greenpeace senior oil campaigner Vicky Wyatt said: "While oil has been flowing, timely information has not. The original leak, now classified as significant, happened on Wednesday, but the news wasn't made public for 48 hours, and now we're learning of a second spill.
"As Shell finalises plans to move into the fragile Arctic, where oil spills are almost impossible to clean up, the company has important questions to answer. Meanwhile the Government should halt its rush to hand out new licences for deep water drilling to the west of Shetland."