Shell offshore Nigeria spill came amid tanker-loading

A faulty pipe from an offshore oil field run by Royal Dutch Shell PLC near Nigeria’s coast spewed crude oil into the ocean for as much as 25 hours as workers loaded a waiting tanker, the company acknowledged today.

While Shell continues to investigate the cause of what likely is the worst offshore spill in more than a decade near oil-rich Nigeria, the nation’s beleaguered government remains largely reliant on the oil firm to clean up the spill. While the huge slick remains offshore, it still poses a danger to wildlife and plants in a region where spills already stain the environment.

The spill occurred at the Bonga offshore oil field, about 75 miles off Nigeria’s coast. The field, which Shell operates in partnership with Italy’s Eni SpA, Exxon Mobil Corp., France’s Total SA and the state-run Nigerian National Petroleum Corp., is controlled from a large ship as opposed to a stationary rig.

Information released by Shell shows workers discovered the spill Tuesday as they tried to fill a waiting tanker with crude oil. Loading tankers takes roughly 25 hours, meaning the spill could have begun at any time during the process.

A London-based spokesman for Shell declined to comment on specifics about the spill, saying a company is still investigating the cause. The company did release an underwater image of the 19-inch pipeline that caused the leak, which showed a rupture along it.

Shell said the leak on the pipe has been plugged and that less than 40,000 barrels of oil has spilled into the Atlantic Ocean. That likely represents the biggest offshore spill near Nigeria since 1998, when roughly the same amount of oil poured out of a Mobil offshore field, sending oil slicks as far as the country’s commercial capital of Lagos.

The Bonga field produces about 200,000 barrels of oil a day and represents about 10 percent of production in Africa’s most populous nation. Shell has said it shut down the field and has offered no estimate of when production could resume at a field vital to Nigeria’s government finances.

An independent watchdog group called SkyTruth suggests the spill could stretch across roughly 350 square miles of ocean. Shell has said it is using helicopters and ships to monitor the slick and have used chemical dispersants on it.

Peter Idabor, who leads the National Oil Spill Detection and Response Agency, said the oil had yet to reach the coast Friday afternoon. He declined to comment further, but federal lawmakers have already criticized the agency for not having the equipment in place to deal with such as disaster.

The agency has “to now rely almost exclusively on the grace and benevolence of the oil companies, in this case Shell, to provide them logistics, equipment and (an) information command and control center,” Sen. Abubakar Bukola Saraki said in a statement.

The publicized spill comes as Nigeria experiences others daily in its oil-rich Niger Delta, a maze of creeks and mangroves roughly the size of Portugal. Since Shell began production there about 50 years ago, environmentalists say as much as 550 million gallons of oil poured into the delta during that time — a rate roughly comparable to one Exxon Valdez disaster per year.

While oil routinely laps up against shorelines and leaves a tub-like ring, the size of the Bonga spill could affect beaches typically untouched by the country’s oil trade. The oil could kill plants like mangroves, palms and shrubs, as well as poison the fish the region depends on for food and trade.

Shell in recent years has said most of the spills in the delta are caused by militant attacks or thieves tapping into pipelines to steal crude oil, which ends up sold into the black market or cooked into a crude diesel or kerosene. Company statistics kept by Shell show spills have dropped as militant attacks in the region subsided, though this single spill at Bonga roughly doubles the amount of oil spilled by Shell this year.

Nigeria, an OPEC member nation producing about 2.4 million barrels of crude oil a day, is a top supplier to the U.S.

3 Comments

  1. ntangle

    Don’t want to jump to conclusions, but the duration of this spill sounds incredible. Even older gas pumps (that don’t require holding the handle in order to run) have an automatic shutoff, for when they lose back pressure.

    #1
  2. mark

    Hard to believe no one noticed the large shiny oil slick in over a day. Though I’m not sure as NTANGLE states there would be that much of a difference in back pressure if the leak was closer to the ship and still far underwater, since the valve was probably wide open going into the ship.

    #2
  3. ntangle

    In the specific combination of circumstances Mark suggests, it wouldn’t have been as simple to detect. Where the leak is at a depth such that the water’s head nearly balances the oil’s pressure at that point. Even then, if there was a relatively sudden rupture, there would be a correspondingly sudden pressure change at the pump. This could be detected, even if the back pressure didn’t drop below some absolute threshold.

    #3