Flaring the gas captured by the riser insertion tool (U.S. Coast Guard ) (The RIT is now pulling up some 2,000 bd)
As an illustration there was a question from Brad Johnson of ThinkProgress, about the size of the spill and that they should know the size of the spill if they are injecting dispersant into the plume.
The answer was
First of all, we do not have the ability to read the outflow at the riser insertion tube. You might think you can, but there was no way to do that. It would have taken longer to design the riser insertion tube if you wanted to attempt to do some sort of a flow rate measurement.Brad has posted a picture showing the relationship of the spill to the Loop Current.
What they do have from the riser insertion tube is they have a way of decanting. Once the oil and gas and water mix reaches the surface on the Enterprise, they can decant. And that's how they were getting the estimate of the thousand-gallons --- or, thousand barrels, excuse me --- estimate of what they've retrieved thus far. And as they get more fidelity on that, how much they get out of the riser insertion tube, they will share that with you. BP will share that with you.
What we also have going on is we have the Minerals and Management Service, the Coast Guard and other federal agencies working on a couple different things. Certainly we want to get fidelity on what we think the estimate of oil is. When you're in a response like this, you have to prepare and respond to a worst-case scenario. So we have been preparing and responding an upward-bound of what could potentially be approximately -- we said 5,000 barrels, but it could be 55,000 per day. That if the well let go, the design engineers will tell you that it could be approximately 55,000 barrels per day.
We don't think we have that much, because we've got satellite imagery; we know what we're responding to. We know how much we're seeing on the surface; we can estimate that. So the upward-bound of worst-case could be approximately 55,000 barrels.
But what's more important is we are doing the analysis. We are working to do the analysis. A federal team is working to do the analysis now, based on the information that we can get from the video and from the ROV, to see if we can get more fidelity on the actual amount. And that's something that will be very important as we go down the road for the national resource damage assessment process and for other things.
Composite of the oil spill (white) and the Loop Current (blues and turquoise) (ThinkProgress )
The Admiral went on:
This is not an exact science. These are all estimates, because the oil and water mix, even as you deal with dispersants, you're trying to figure out what's the analysis of how much we have applied on the surface and subsurface, and what's the estimate of the efficacy of that. There's a thing called the fate of the oil. And they are doing an analysis to figure out how much do we think we've really been dealing with since the start of this response? So both of those things -- the estimate of the out-flow, based on the video analysis, and then also the efficacy of the response.And a subsequent clarification:
We were comfortable with the estimate that was given, the 5,000 barrel per day estimate. It's only an estimate. I was comfortable with working from that. Did I think it was exact? No. I've never trusted that. I've never personally trusted that as an exact number. We are responding daily to what we see and what we are experiencing in the cleanup. And it is a very, very good cleanup thus far. I think we're having good success thus far. . . . . the reason we've taken it as seriously as we have and the reason we have 20,000 people and all the response equipment in place is because since day one, we have always prepared for a worst-case. That it could be 55,000 barrels per day, which is an extraordinary amount which would have tremendous impact.
Leslie Berliant of SolveClimate was concerned about the pre-approval of the dispersant and the risk it might bring to coral reefs. (The topic had previously been addressed at that blog).
In her answer the Admiral noted the passion that the civil servants working on this bring to their work.
We have a unit called the environmental unit, and if you could listen to them and see how many hours they've worked at this and how much they've really debated and discussed how important it was to make sure all of the sampling protocols and everything was in place, to ensure they capture every element of this threshold. I cannot emphasize enough that people did not proceed into this very lightly.(This is something I have noted a number of times, many folk who comment do not understand how passionate about the environment many state and federal officials are, and how there is indeed a considerable scrutiny by many qualified folk of the efforts, and the questions do get aired and debated).
The Admiral also talked on the need to co-ordinate all the different efforts that are now taking place in the Gulf, across parish, state, and federal levels and with the great variety of state agencies. The Unified Command site notes:
• Personnel were quickly deployed and more than 20,000 are currently responding to protect the shoreline and wildlife.
• More than 950 vessels are responding on site, including skimmers, tugs, barges, and recovery vessels to assist in containment and cleanup efforts—in addition to dozens of aircraft, remotely operated vehicles, and multiple mobile offshore drilling units.
• More than 1.36 million feet of containment boom and 480,000 feet of sorbent boom have been deployed to contain the spill—and approximately 350,000 feet of containment boom and 800,000 feet of sorbent boom are available.
• Approximately 7.6 million gallons of an oil-water mix have been recovered.
• Approximately 640,000 gallons of total dispersant have been deployed—590,000 on the surface and 53,000 subsea. More than 300,000 gallons are available.
17 staging areas are in place and ready to protect sensitive shorelines, including: Dauphin Island, Ala., Orange Beach, Ala., Theodore, Ala., Panama City, Fla., Pensacola, Fla., Port St. Joe, Fla., St. Marks, Fla., Amelia, La., Cocodrie, La., Grand Isle, La., Shell Beach, La., Slidell, La., St. Mary, La.; Venice, La., Biloxi, Miss., Pascagoula, Miss., and Pass Christian, Miss.
The area that is restricted has been increased:
The closed area now represents 45,728 square miles, which is slightly less than 19 percent of Gulf of Mexico federal waters. This leaves more than 81 percent of Gulf federal waters—or nearly 195,000 square miles—still available for fishing. Details can be found at http://sero.nmfs.noaa.gov/.
The newly closed area is more than 150 miles from the nearest port and primarily in deep water used by pelagic longline fisheries that target highly migratory species, such as tuna and swordfish. Coastal fisheries, such as grouper, snapper and shrimp, will not be affected by the expansion of the closed area.