Disconcertingly long lead time needed to clear out from Deepwater Horizon site
June 22, 2010
As one could guess from references to it in my past few posts, the thought of a storm disturbing oil recovery efforts in the Gulf has been at the top of my mind. One thing I’d had in the back of my mind as a curiosity was the sort of lead time that the response team was looking for. I was hoping that it was in the 48-72 hour time-frame. The matter came up in today’s briefing with Admiral Allen and the answer to the required lead time question is worrisome. I’ll give the entire Q&A with boldface added for the part in question.
Q: Hi. Thank you. There’s been some reports that the first major storm of the hurricane season might enter the Gulf as soon as next week. Could you walk us through what will happen with the collection operation if that happened next week?
ADMIRAL ALLEN: Sure. First of all, we’re watching the hurricane season very, very closely. I’m in constant contact with Jane Lubchenco, administrator of NOAA, and in fact, this week I talked to Craig Fugate, the FEMA administrator. We are informing each other of our respective operations. Of course you know they were involved with hurricane prep, so they would be anyway this time of year. And we do have that low depression that’s been informed in the Southeast Caribbean, and we’re watching that as well.
How we respond to a hurricane will be dictated by which production capacity we have on scene, and as you know this is evolving and will continue to evolve over the next two to three weeks. By the end of next week, let’s say, we would anticipate having three production vessels out there over the well site; the Discovery Enterprise, the Q4000 and the Helix Producer. Of those production capabilities, one of them is fixed hard to do the platform itself, and that’s the Discovery Enterprise down to the wellbore. The other two are on flexible couplings for vertical riser packages.
We would need in total to disconnect, recover to a safe harbor and return probably around 10 days to accomplish that, and we would probably have to start doing that anywhere between three to seven days in advance of the hurricane. Those procedures are being finalized right now. We’re discussing that with BP and the folks that are down at the area unified command in New Orleans. But if it happens—if we got notice that a hurricane was coming, we would need anywhere from three to seven days in advance of that to demobilize and redeploy the equipment.
Is that responsive?
Q: What kind of storm would have to be coming your way for you to do that? How—what kind of wind speed, or could you give anymore specifics on that?
ADMIRAL ALLEN: Well, what we’re going to do is—I was asked the question yesterday. I asked some folks working on how are mooring systems related to Saffir-Simpson Scales, because I think that’s the easiest way for people to understand that. And we will get that out to you in the next 24 hours. But basically, the least capable platform that’s in production to ride out heavy weather would be the Discovery Enterprise because it’s physically hooked to the well itself.
Anything that’s working through our vertical riser that’s floating with a flexible hose coupling will have a little bit more flexibility as far as the sea state, and the large vessels that will be coming on later in July, the shuttle tankers, have much more sea keeping capability, although none of them are designed or created, nor are the production mooring facilities and everything else, created to withstand a major hurricane. Exactly when the cutoff is as far as the sea state goes, we will put that together, and we’ll give you a brief in 24 hours.
If the required lead time is not in the front part of the range that he gives, it needs to be. 5-7 days can be an eternity for tropical weather affecting the Gulf of Mexico. Consider Tropical Depression Twelve of 2005. Advisory number 1 came out on the afternoon of August 23 in the Bahamas. On the evening of the 25th, with the depression now a hurricane, the forecast cone of uncertainty started to cover the location of the Deepwater Horizon. The hurricane made its closest point of approach (~60 miles to the west) on the morning of the 29th. The hurricane, of course, was Katrina.
From the time of formation to the time that the area in question was under hurricane force winds was a mere five and a half days. The time from when one would think “Oh crud, this just might be headed our way” to arrival was even shorter; three and a half days. If it really would take seven days to clear out, the recovery team would either A) Have to start packing up anytime a storm (or developing system) is west of Hispanola / in the Bahamas or B) Find themselves distinctly screwed if a hurricane were to make its way to them on day five or six. Needing three days notice is pretty workable, while five is ok if they are willing to put up with false alarms; needing longer than that sets them up for an ugly situation.