New Orleans, Louisiana (CNN) -- Oil companies Shell and BP began evacuating nonessential personnel from their drilling platforms in the Gulf of Mexico on Saturday as officials kept a wary eye on a tropical storm churning toward Mexico that could wreak havoc on oil spill cleanup efforts. As much as 2.5 million gallons of oil could flow into the Gulf for two weeks if Tropical Storm Alex forces a work stoppage at the ruptured BP well, the government's disaster response manager said. Adm. Thad Allen said gale-force winds near the well head would prompt an evacuation of the thousands of workers and vessels involved in the oil recovery and cleanup effort.
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NEW: Shell, BP evacuate nonessential personnel from Gulf of Mexico platforms
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If stopped, oil recovery could be suspended for two weeks
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Alex could push more oil ashore
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Alex moving toward Mexico's Yucatan Peninsula
While protesters lined the sand, Alex moved toward Mexico, no one knowing whether it would make a sudden turn north into the open @placeholder.