Only 10% of Gulf Oil Cleaned Up Scientist scolds administration for rosy estimates By Kevin Spak, Newser Staff Posted Aug 19, 2010 7:41 AM CDT 16 comments Comments In this June 6, 2010 file photo, a small dead fish floats on a pool of oil at Bay Long off the coast of Louisiana. (AP Photo/Charlie Riedel, File) (Newser) – Only 10% of the oil that spewed from the Deepwater Horizon well has been "actually removed from the ocean," a leading oceanographer will tell Congress today. Ian MacDonald's testimony throws cold water on a cheerful federal report earlier this month that declared 75% of the oil had either been cleaned up or broken down. MacDonald also says the government is taking a decidedly optimistic view on how fast the rest will biodegrade. MacDonald’s findings are based in part on satellite imagery. He’ll also cite Gulf oxygen levels, which aren’t consistent with rapid oil degradation, according to the Wall Street Journal. The head of the NOAA brushed off the testimony, saying, “We stand by the calculations we released.” But evidence is mounting that much of the oil is still out there, either suspended below the surface or in the seabed.