Nigerian officials said they expect oil leaked from a Royal Dutch Shell offshore well to reach the country's shores Thursday. Shell officials suspect half of the estimated 40,000 barrels of oil leaked in the Atlantic this week have already naturally dissipated or evaporated, according to the company's website.
The leak happened Tuesday, when oil was being offloaded onto a nearby tanker from the company's storage and off-loading vessel. The company said 40,000 barrels of oil, at most, have leaked into the ocean.
The well, company officials said, has been shut in since the leak was reported. Peter Idabor, who leads Nigeria's National Oil Spill Detection and Response Agency, told the Associated Press he expects the oil slick to reach beaches by Thursday.
Shell acknowledges that although the oil sheen on the water is large, in most areas, the estimated thickness of the sheen is less than one millimeter.
Company officials on Wednesday stressed the leak was not due to a malfunction of the well and that no one was injured.
We are sorry this leak has happened, said Mutiu Sunmonu, Shell's country chair in Nigeria. As soon as we became aware of it, we stopped the flow of oil and mobilized our own resources, as well as industry expertise, to ensure its effects are minimized.
This last leak is likely to be the worst in a decade in Nigeria and has affected 115 miles of ocean, AP reported Thursday.
The latest spill of this magnitude in the country, reported the AP, was one in 1998 at a Mobil offshore field. Oil in that spill stretched more than 100 miles.
Nigeria's latest oil spill came at the same time as Shell reported a minor spill in the Gulf of Mexico, and more than a month after human rights group Amnesty International pressured the Dutch subsidiary to dedicate $1 billion to clean up two previous oil spills that damaged the Nigerian river delta's farmland and waterways.
Amnesty International claims Shell's Nigerian Subsidiary allowed two pipeline ruptures to go on unabated one after the other for several weeks, leaking 1,600 to 4,000 barrels a day in the country's delta in 2008.
Shell has taken responsibility for the two 2008 spills, but maintained that the integrity of its land-based operations in the country has been hampered by illegal oil theft and refining, which involves siphoning crude oil from active pipelines.
Since 2006, according to a company briefing published in April 2011, Shell Nigeria has dealt with an average of 169 oil spills a year in the country, and cleanup efforts have repeatedly been frustrated by theft that caused subsequent leaks.