http://news.yahoo.com/...
HOUSTON (Reuters) – BP Plc Chief Operating Officer Doug Suttles said on Wednesday it appears drilling mud, not oil, was gushing from a ruptured undersea well six hours into an effort to halt a growing oil spill.
"What you've been observing coming out of the top of that riser is most likely mud," Suttles said at a news conference broadcast from a Louisiana command center. "We can't fully confirm that because we can't sample it. And the way we know we've been successful is it stops flowing."
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It looks like mud to me, but I wouldn't know the difference.