Current Events

Join us as we watch the crisis unfolding

March 29th, 2011

Macondo — Fukushima

Macondo

One of my former students, Joel Achenbach, has a book being released this week about the BP blowout. (A Hole at the Bottom of the Sea.) His e-mail a week ago asked whether there were parallels between the BP Macondo blowout and the damaged nuclear reactors at Fukushima. My first reaction was "No," but it was wrong. BP treated their blowout as a string of unlikely events that came together by accident. The BP analogy was a random stack of Swiss cheese slices and the rare occasion when a hole in all of the slices happened to line up. I had been going along with the Swiss cheese analogy, although I was using only two slices of cheese. The first unlikely event was a fracture at the bottom of the well and the second rare event was the failure of the blowout preventer to close. If the break at the bottom of the hole has a probability of one chance in 1000 of happening and the blowout preventer fails only one time in 1000 tries, then the wild well happens only once in a million times. That's the approach from Statistics 101: multiply the two probabilities together. That's the Swiss cheese interpretation, but it may not apply to the Macondo blowout. The blowout preventer autopsy from Det Norsk Veritas suggests a different interpretation; an interpretation with a haunting parallel to the Fukushima disaster.

The BP Macondo-well blowout happened on April 20, 2010. In an e-mail to my friends and relations on April 23, I guessed that the blowout was caused by a "casing-shoe failure." Further, I posted the same opinion in this Current Events series on May 3. Back in the bad old days, a casing shoe was a one-way valve inside an enclosure at the bottom of a string of casing. The one-way valve allowed flow downwards through the casing, but not flow upwards. One of the purposes of the valve was to allow the air-filled casing to be lowered into the hole, largely supported by its own buoyancy. Once the casing reached the desired depth, cement was pumped down the inside of the casing, through the one-way valve, and up into the space between the casing and the surrounding rock. Erle P. Halliburton invented the technique; that's the same Halliburton Company that cemented the Macondo well.

You are warned that I am not a licensed petroleum engineer. Some of my opinions would have serious legal implications if they were provable. As yet, I have not seen the original Norwegian blowout-preventer report. This is being written based on news reports and secondary sources. ¡Cuidado!

The Macondo casing string used a modern modification of the traditional casing shoe. The one-way valve, located a distance above the bottom of the casing, is known as a "float collar." The Macondo casing actually had two float collars, one above the other. The whole assembly from the casing bottom to the float collars is known collectively as a "float string." The word "float" appears because the buoyancy of the air-filled casing lowers the stress on the steel casing as it is being lowered into the well.

Initially, and even today, I find the casing-shoe (or float-string) failure to be the most likely interpretation. Although there may have been early warning signs, the actual blowout began abruptly as mud from the hole began shooting over the top of the derrick. Within 10 minutes, natural gas arrived at the surface and caused the explosions. The rapid onset suggested to me that the flow was upwards through the open casing and not through a tortuous passage up through a partially-cemented annulus outside the casing. Ten minutes is a plausible time for a flow of 50,000 barrels per day to displace the mud from inside the casing. About a month ago, the US government released a BP animation showing the blowout as a failure at the bottom of the casing. C21462-298_CCR_Cement_Job_Sequence. One note: there is a "Z" symbol in the pipe, meaning that a long, uninteresting, length of pipe has been omitted.

The downhole failure would not have created a disaster if the blowout preventer had functioned properly. There has been much discussion about the redundant ways for activating the blowout preventer. However, a different story emerged from the forensic examination of the Macondo blowout preventer by the Norwegian company Det Norsk Veritas. The upward flow out of the well bore buckled and jammed drill pipe into one corner of the blowout preventer. As a result, the blowout preventer couldn't cut it. This fed back into an earlier puzzle: When BP was trying to cut off the base of the riser, there were two parallel lengths of drill pipe stuck inside the riser. The Norwegian conclusion caused one expert to comment that ALL existing blowout preventers could be subject to the same failure mode.

Although it is not intuitively obvious that upwards-flowing oil and gas could lift and deform heavy steel drill pipe, there is a dramatic piece of evidence. There is an old black-and-white documentary movie about Myron Kinley's capping a major Middle East wild well. At one point in the movie, Kinley needs to get the drill pipe out of the way. They got everyone, including the cameraman, far back from the well and opened the blowout preventer. Drill pipe snaked up into the sky like a strand of cooked spaghetti. Yes, friends, a wild well can lift and deform drill pipe. (Incidentally, I have not been able to locate a copy of that movie. If any reader can find a copy, please e-mail me at deffeyes@princeton.edu.)

If the Norwegian conclusion is correct, we can abandon the Swiss cheese analogy. As soon as the bottom-hole failure occurred, the blowout preventer was doomed. We have a single cause and multiple consequences. This brings up an old, very old, piece of advice from William of Occam in the early 1300s: Give serious consideration to the simplest hypothesis that fits the observations. Joel Achenbach gives a modern discussion of the same principle on pages 239-241 of A Hole at the Bottom of the Sea.. If the bottom-hole, single-cause hypothesis is true, then a huge number of other purported "clues" to the puzzle are then irrelevant, both intellectually and legally.

Fukushima

The Japanese earthquake on March 11 was clearly a single cause with multiple results. In this instance, we do not multiply probabilities, we simply add up the consequences. The Great Tohoku earthquake, magnitude 9.0, was one of the five largest earthquakes since seismometer recording began in the year 1900. Further, it happened in a heavily populated region. Before we get to the ugly part, we should congratulate the Japanese on the relatively small loss of life and property caused by the earth-shaking part of the earthquake. The accompanying tsunami was another matter. Some historic coastal towns were completely wiped away. The earthquake itself was expected only in a general, statistical way. However, a magnitude 9 earthquake in that part of the Japan Trench was a low-probability item. If it wasn't exactly a black swan, it was at least a dark charcoal-gray swan.

At the six Fukushima Dai-Ichi nuclear reactors, there were two almost-immediate consequences of the earthquake. Power from the electric grid was lost due to the earthquake shaking in the region and the local backup power facilities were destroyed by the tsunami. With those two gone, the ability to pump cooling water to the reactors was lost. Dai-Ichi was toast, burnt on both sides.

The early news stories emerging from Fukushima were enormously confusing. I started a score card with the six reactors along the 11-inch edge of a page and time flowing down the 8 inch edge. Two workers are hospitalized with radiation burns. Reactor number 3 is of particular concern because it is fueled with a plutonium-uranium mixture. Serious amounts of radioactive material are being released and it is not clear yet how much is coming from the nuclear reactors and how much is coming from the spent-fuel storage ponds. As of today (March 27) there are some unconfirmed reports that the total radioactivity released from Fukushima is 20 to 60 percent of the release from Chernobyl. The battle to contain Fukushima is still in progress.

Regardless of the outcome of The Battle of Fukushima, the nuclear disaster very likely has put the kibosh on the construction of new nuclear power plants around the world. Some countries are even considering closing their existing nuclear plants. We can expect the strongest rear-guard action to come from France. French electric power is 75 percent nuclear and France has an excellent safety record. An additional French motivation is their worldwide nuclear service company: Areva. Notice also that France took the early lead in conducting the air war over Libya, using their Dassault fighter jets. How far does this go back? Remember that the Palace of Versailles was built as a showplace for French products.

So how does our energy supply look in a post-Macondo, post-Fukushima world? Not so good. Permits are being issued again for drilling in the Gulf of Mexico, but we have lost almost a year because of the BP Macondo blowout. In the February 14 Current Events, a graph was posted from my book, When Oil Peaked, showing a danger level for crude oil purchases above five percent of Gross Domestic Product. Crude oil prices continue to climb. Gasoline and food cost more as a result. How are we supposed to climb out of this recession when we have BP's boot on our neck?

Gas prices in San Diego, March 28, 2011

Although the US government has put additional coal-bearing land in the Powder River Basin up for leasing, substantial increase in coal burning will probably involve coal gasification and carbon dioxide sequestration.

Natural gas is our last remaining opportunity. Currently, there is controversy concerning the hydrofracturing fluids used in natural gas wells. Rather than campaign for effective tracers to be incorporated into frac fluids, many citizens have simply opposed natural gas drilling programs. Unfortunately, I regard that opposition as evidence of economic suicidal tendencies.


 
 
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