Monday, May 17, 2010

The Gulf oil spill, recovery and cleanup - Monday's Press Conference

Today’s press conference in Louisiana began with an update on the use of the riser insertion tool. However Coast Guard Admiral Landry cautioned that this only treated part of the spill, and that they were looking forward to the “top kill” program that would follow. The weather is now good enough that four controlled burns are planned, as well as a strong skimming program. To date there has been a minimal impact on the shore from the spill, but teams are in the field ready to react as this becomes more severe. Further the high flow rates from the Mississippi River are helping keep the larger volumes of the spill out in the Gulf. Both NOAA and the EPA are monitoring the use of dispersants recognizing the tradeoff between its use and the damage that it is mitigating.

The Admiral drew attention to the statement by Jane Lubchenco, the head of NOAA, who had said, in regard to the many reports of large underwater oil plumes and their causes and likely effects
"Media reports related to the research work conducted aboard the R/V Pelican included information that was misleading, premature and, in some cases, inaccurate," Lubchenco said in a statement. She was referring to research, including water sampling, done by the National Institute for Undersea Science and Technology.

Lubchenco said those scientists have clarified that (in regard to the plumes) they have not reached "definitive conclusions ... about the composition of the undersea layers they discovered. Characterization of these layers will require analysis of samples and calibration of key instruments. The hypothesis that the layers consist of oil remains to be verified."

This has been later qualified by Vernon Asper, one of the scientists involved who said, among other things:
1) We are not 100% sure that the plumes are oil. We have NOT analyzed the samples yet and won’t know what’s in them until we do. That will take at least a few days or even a week or more and we don’t want to rush these results. The sensor we used is not definitive for oil and other compounds do respond in a manner that is similar to oil and could be confusing us.

2) I NEVER said that these “plumes” could cause a dead zone! It’s really important that you correct that! Consider:

a. We don’t even know if there is any oil in the plumes so the oxygen signal we’re seeing could be due to something else that is going on near the well and, if so, it could disappear overnight (we just don’t know

b. The oxygen levels we saw are lower than “normal” but are no where near the danger zone! For the most part, they are not even as low as the layer above them that we call the “oxygen minimum zone.”)
The NOAA Administrator was also on PBS where she again said that it was too early to speculate on what was in the plumes, and that there was a light oil sheen on the surface that might reach Florida in 9 – 12 days, but that it would be very dilute, and may just show up as tar balls, with little prospect of significant damage to distant beaches. She noted that the threat sounds scarier than it is.

MMS confirmed that the permit for the second well has been approved, and is in process. They pointed out that any procedure being carried out has first to be reviewed and permitted by MMS after ensuring that it will have minimal environmental impact and be safe. They also emphasized that the monitoring and regulatory side of MMS will be strengthened.

For their part Doug Suttles of BP noted that at the time of the briefing on the afternoon of the 17th, they were getting a little over 1,000 bd up through the Riser Insertion Tube (RIT). And they are now slowly opening the choke to ensure no hydrate formation.

Later this week they will run the top kill procedure, that will start to close out the well sealing process. The use of the RIT and of dispersant has reduced the size of the oil slick appearing on the surface.

In response to questions from the floor Mr Suttles said that if the RIT could recover more than half the flow out of the riser (which he characterized as a 2,000 bd target) that they would all be very pleased. He stressed that they did not want to draw too much fluid into the system, since that would lead to hydrate formation and another blockage of the line. And later he noted that they hadn’t decided yet what to do with the oil that they are capturing. (Though he also ducked a more definite confirmation of the actual volume that is leaking).

Admiral Landry said that the oil had not entered the Loop Current at this time. The larger volumes of oil are several miles from it, while there is a surface sheen that is getting closer.

Doug Suttles further explained the top kill by pointing out that the mud will be introduced at high velocity through the two 3-inch diameter choke and kill lines into the BOP. However he also clarified the position of the RIT, which I had thought was close to the BOP. It is, however, almost 5,000 ft up the riser, at the open end. The top kill is anticipated to stop the flow, after which cement will be injected. That will stop the flow, but BP will go ahead with a relief well to reach, and then pump cement into the bottom of the well which will finally secure it. He stressed that there was no intent ever to produce oil from this well. (Because the oil-bearing formation around the well is now degraded into a condition that is no longer controllable). The final decision as to whether to use “top kill” or “junk shot” first has not been made, but the inclination is to use top kill since it has less risk of precluding the alternate technique if it should not work.

Before they committed to the top kill they had to know the pressure on both sides of the BOP. They now have that data, and found that the pressures were quite low, less than expected, and were falling. They then had to remove the “yellow pod” on the BOP sine this carries the controls for the valves to the choke and kill lines, and these controls had to be modified to allow the top kill to take place. The pod has been prepared, but has not yet been taken underwater and replaced. That will happen soon.

The Admiral also emphasized that even though the oil may stop flowing out of the well at the end of the week, the studies and investigations of what is going on will continue for a long time. Further all the steps that are being made are being reviewed at several levels in different government agencies to ensure that they do what is needed, with minimal impact, while working out where all the oil and dispersant has gone.

Charlie Henry of NOAA clarified the comments about the “oil plumes” noting that the samples were so clear that you could not, by eye, see anything in the water. To find out what really is in the water will require an analysis, that has not yet been done, of what is actually there. There is also a lot of research and monitoring to see where the oil is going, and in what condition. This is the adaptive management of the process which must change as results come in on what is going on.

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