The oil on the surface of the gulf is shrinking, which is welcome news. But Susan Shaw continues to worry about the deep sea:

More caveats here. Kate Sheppard reports on natural gas, which was "some 40 percent of what is escaping from the well":

In the 10-mile radius around the well site, research teams have measured methane levels in the water averaging 100,000 times normal levels. [John Kessler, a professor of earth system science at Texas A&M University] says levels are up to a million times normal in parts of the Gulf immediately surrounding the spill site. "This is the highest concentration I've ever seen in ocean waters, easily," says Kessler. He believes it could take yearspossibly decadesfor the gas levels in the ecosystem to return to normal.

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