By Kristen Hays and Tom Bergin
HOUSTON/LONDON (Reuters) - The approach of Tropical Storm Bonnie Friday forced BP <:BP.LO:>Plc to halt efforts to permanently plug a gushing oil leak in the Gulf of Mexico, sending ships and workers retreating to safety.
Two rigs stopped drilling the relief wells intended to halt the leak for good and prepared to move out of the path of the storm, which was expected to hit the spill area Saturday with winds of 39 to 73 miles per hour (62-117 kph).
Many non-essential workers already have abandoned the spill site, and officials said key ships would likely pull out later Friday and be gone about two days.
Ships collecting seismic and acoustic data on the capped well and those operating underwater robots that provide a live feed of the wellhead would be the last to leave, and could stay if seas do not become too rough, officials said.
"If we have to evacuate the scene we're probably looking at a very limited window -- probably 48 hours," retired Coast Guard Admiral Thad Allen, the top U.S. spill official, told reporters.
BP sealed the leak last week with a tight-fitting containment cap, choking off the flow of oil for the first time since an April 20 rig explosion killed 11 workers and sent crude spewing into the Gulf, soiling coastlines and devastating tourism and fishery industries.
The evacuation could push back BP's mid-August target date for a permanent solution to the leak to late August. But the blown-out well will remain capped during the halt to operations, easing fears the gushing leak would resume.
The evacuation also delayed another potential solution, the launch of a "static kill" operation to pump heavy drilling mud and possibly cement into the well.
BP said workers were securing eight company-operated platforms in the Gulf and preparing for a full evacuation of workers.
The U.S. government said Friday 28.3 percent of Gulf oil production and 10.4 percent of Gulf gas output by all companies had been shut ahead of the fast-moving storm.
STORM IMPACT MIXED
Allen said the storm could have benefits and drawbacks for containment efforts. Heavy waves and tidal churn could help break up the oil more quickly, but high winds and waves could drive it deeper into fragile wetlands and coastal areas.
"In some scenarios it might actually be good for cleansing the system, but in other circumstances it might cause even more problems if it blows a lot of the oil directly onshore," said Chuck Kennicutt, a professor at Texas A&M University who studied the 1989 Exxon Valdez spill in Alaska.
BP's containment efforts have been watched closely by investors because its ultimate costs may hinge on how much oil is determined to have flowed into the Gulf.
Company shares were up about 1.5 percent in early afternoon trading in New York while the broader market remained flat. BP shares closed relatively flat in London, down 0.3 percent.
The company's second-quarter results are due Tuesday. Analysts at Barclays bank said BP could report a loss for the second quarter of $13 billion (8.4 billion pounds) as it makes provisions of up to $25 billion for the cost of the oil spill -- far outweighing an expected 77 percent jump in underlying profits.
The administrator of a $20 billion fund set up by BP to help compensate spill victims said the fund would not prevent future lawsuits against the company that exceeded that amount.
"The notion that the fund is there simply to insulate BP from lawsuits I think is very unfair," Kenneth Feinberg told reporters.
BP's response to the largest offshore oil spill in U.S. history has been marked by a series of public relations gaffes by top management. Calls have grown for the ouster of Chief Executive Tony Hayward.
Friday, BP said it had removed doctored photographs of its oil spill response effort from its website, blaming a "simple error" that analysts said would further damage its already battered credibility.
BP published a photograph of a helicopter near the spill site which had been altered to give the impression the aircraft was in flight and to give a clearer view of vessels working on the relief effort.
Two BP managers have been named as subjects of a U.S. federal investigation into the explosion of the Deepwater Horizon oil rig, the Wall Street Journal said.
The U.S. National Hurricane Centre said Bonnie, the second named storm of the 2010 Atlantic hurricane season, was on a track that could take it over the BP spill site before it hits the Gulf coast. Louisiana Gov. Bobby Jindal declared a state of emergency.
U.S. First Lady Michelle Obama visited an emergency operations centre in Pascagoula, Mississippi, for a briefing on the spill. She was joined by Homeland Security Secretary Janet Napolitano.
"The administration is going to stand with the people of the Gulf until they are made whole again," she said.
President Barack Obama, under political pressure for his handling of the spill, plans to spend the August 14 weekend along the hard-hit Florida Gulf Coast.
(Additional reporting by Chris Baltimore in Houston, Pedro Nicolaci da Costa in Washington; Writing by John Whitesides; Editing by Jackie Frank)
