New spill estimates released August 2 suggest that 4.9 million barrels of oil (give or take 10%), or 205,000,000 gallons have been released from the Deepwater Horizon oil well.  Of that, they estimate that about 16%, or 800,000 barrels (33.6 million gallons) has been captured. For comparisons sake, the Exxon Valdez spilled 750,000 barrels (31.5 million gallons), and this spill now exceeds the former-largest spill, the 1979  Ixtoc I, which released 140,000,000 gallons.  How they achieved this new estimate is described on the  Deepwater Horizon Unified Command page:

The installation of a new containment cap and the subsequent well integrity testing procedure provided the opportunity to calculate the flow by measuring the pressure at the top of the well as the choke and kill valves were manipulated after the main containment valve was closed to trap hydrocarbons.

Also of interest on the Deepwater Unified Command page was the EPA’s release of the results from toxicity testing on “mixtures of eight oil dispersants with Louisiana Sweet Crude Oil.” The result: “dispersant-oil mixtures are generally no more toxic to the aquatic test species than oil alone.” A link is provided on their page to the tests results.

On other note, the spill is having an impact as far north as Canada. According to the Ontario Star newspaper, as fall approaches the issue of migratory birds that winter in the Gulf Coast region has come into focus. Of major concern are white pelicans, which just came off the endangered species list, but many other birds could be “flying to their demise”. This is impacting many segments of Canadian society:

Scientists aren’t the only ones concerned about the impact the spill may have on Canada’s migratory birds. Aboriginal groups who have for centuries hunted ducks, geese and other waterfowl to feed their families are urging Prime Minister Stephen Harper and U.S. President Barack Obama to get involved.

The article mentions a program established by the USDA’s Natural Resources Conservation Service which has set up the “Migratory Bird Habitat Initiate” in an effort to mitigate this problem. They are paying farmers in portions of eight states to flood their fields in order to “enhance habitat for migratory birds”.

The Diva will be back from vacation tomorrow. Claire, thanks for letting me stand in for you!

Guest Blogger, Kim Stephens