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Government, Independent Lab Results Confirm Recent Anomaly Algal Bloom, not Oil

NEW ORLEANS - Final lab results, from government and independent labs, came back Thursday showing that samples taken of reported oil in West Bay, La., were absent of any crude oil, confirming initial findings that the discolored water was the result of an algal bloom.

The large, orange blooms of algae in the nutrient-rich West Bay waters closely resembled the emulsified oil seen several months ago before BP's Macondo well was capped.

Response teams aboard vessels and aircraft deployed to the area and made a visual determination that the large orange mass was algae. Samples were taken Saturday and sent to Entrix for analysis and confirmation. The returned analysis concluded the following, "Sample contains some mid-range nC17 - nC20 molecular weight hydrocarbons consistent with a biological source. Negligible unresolved complex mixture, few resolved n-alkanes, steranes and triterpanes. Conclusion: No crude oil present."

Additional samples were taken by a Coast Guard pollution investigator and sent to the Coast Guard's Marine Safety Lab for analysis. The Coast Guard Marine Safety Lab scientist reported, "The six samples collected on Saturday do not contain a quantity of petroleum detectable by the analysis conducted. Traces of hydrocarbons consistent with biological material were detected."

In the more than 15,000 observations of snare sentinels, deployed in 597 locations along the Gulf Coast to detect surface and subsurface oil -- including 449 locations along the Louisiana coast -- 99.4 percent of those observations resulted in no detection of oil. The last time a snare sentinel detected oil was Sept. 20.

In his weekly news briefing, Rear Adm. Paul Zukunft, federal on scene coordinator, discussed the unified area command's commitment to continuing the response effort; "we still have on immediate standby a number of vessels ready to respond and in fact our posture going through the winter months throughout this spill is that we will continue to maintain that rapid response capability. And even though in a number of areas we're not seeing any oil, we have a long term monitoring plan that is still response oriented."

Click to see a larger graphic of the search patternClick to see a larger photo of the algae bloom