The Deepwater Horizon Disaster

Deepwater Horizon Oil Slick Estimate

By now you’ve all heard of the environmental disaster in the Gulf of Mexico but my sense is the media (along with BP) is underplaying the scope and size of the disaster. Others like the Governor Perry set it as an “act of God”.

Perry questioned whether the spill was “just an act of God that occurred” and said that any “politically driven” decisions could put the U.S. in further economic peril.

“From time to time there are going to be things that occur that are acts of God that cannot be prevented,” Perry said.

His line of thinking offers a foil to liberal groups and lawmakers who are calling for an immediate halting in off-shore drilling, something that the Obama administration has championed. MoveOn called for President Barack Obama to reinstate the ban on off-shore drilling Monday.

There’s a much more mundane explanation. Dr. Ian MacDonald at FSU just produced a new spill-size estimate based on the U.S. Coast Guard image above. According to Dr. MacDonald, the map implies that on April 28, there was a total of 8.9 million gallons floating on the surface of the Gulf. Backtracking gives us a flow rate of over one million gallons per day blowing us past the Exxon Valdez disaster. A “not public” report by NOAA suggested that the 5000 barrel could be off by an order of magnitude. For reference 50000 barrels would be 2.1 million gallons of oil per day.

The underestimated size of the oil slick is only half of what is not being emphasized in the media. There’s also this story in the Wall Street Journal.

Blowout Protector

The oil well spewing crude into the Gulf of Mexico didn’t have a remote-control shut-off switch used in two other major oil-producing nations as last-resort protection against underwater spills.

The lack of the device, called an acoustic switch, could amplify concerns over the environmental impact of offshore drilling after the explosion and sinking of the Deepwater Horizon rig last week.

The accident has led to one of the largest ever oil spills in U.S. water and the loss of 11 lives. On Wednesday federal investigators said the disaster is now releasing 5,000 barrels of oil a day into the Gulf, up from original estimates of 1,000 barrels a day.

U.S. regulators don’t mandate use of the remote-control device on offshore rigs, and the Deepwater Horizon, hired by oil giant BP PLC, didn’t have one. With the remote control, a crew can attempt to trigger an underwater valve that shuts down the well even if the oil rig itself is damaged or evacuated.

The efficacy of the devices is unclear. Major offshore oil-well blowouts are rare, and it remained unclear Wednesday evening whether acoustic switches have ever been put to the test in a real-world accident. When wells do surge out of control, the primary shut-off systems almost always work. Remote control systems such as the acoustic switch, which have been tested in simulations, are intended as a last resort.

Nevertheless, regulators in two major oil-producing countries, Norway and Brazil, in effect require them. Norway has had acoustic triggers on almost every offshore rig since 1993.

The entire industry has been fighting regulation by the MMS. I checked the WSJ’s assertion about the so-called acoustic switch with industry expert, Bob Cavner, shown being interviewed by Fox News here. It’s amazing all the “reporter” was interested in was the “terrorist” angle. I guess she was taking orders from Rush.

…lest we forget, the carbon tax bill — Cap and Trade — that was scheduled to be announced on Earth Day. Then it was postponed, a couple of days later… what better way to head off more oil drilling, nuclear plans, than by blowing up a rig? I’m just noting the timing, here.

Here’s his response:

There’s actually nothing known as an “acoustic switch”. There is, however, an acoustic control system that does not rely on an umbilical from the rig floor to the BOP [Blowout Protector] on bottom for communication. If this system had been in place, it possibly would have prevented this incident, since if communication from the rig is lost, the BOP automatically closes.

However, if there was a tool, casing hanger, or other obstruction in the shear rams, that would have prevented the BOP from sealing the well, and it still would be flowing.

I believe, though, that this new system should be required on all deepwater drilling operations.

He said the following on his blog today:

Over the weekend, I’ve learned a lot through my own research and through contacts within the industry about BP’s blowout well, Mississippi Canyon Block 252, and, even though BP and Transocean remain silent as to the condition of the wellhead and BOP (blowout preventer), it seems that consensus is growing that the damage to the stack, 5,000 feet below sea level, is serious and likely irreparable. My sources tell me that ROVs have worked directly on the BOP, doing everything that should have activated it and it has failed to close. It is believed that something may have initially jammed the shear rams and they failed to close; however, the BOP was subsequently severely damaged by the stress of the collapsing riser that remained attached as the Deepwater Horizon sank. The riser was 5,000 feet of 21″ diameter pipe, some buoyant, some negatively buoyant, putting huge forces at the stack on the sea floor as it sank.

My understanding is that the flowing wellhead pressure may be as high as 10,000 PSI and that, even if the BOP could be closed now, could very well be leaking in the locking mechanism below the stack. Leaks always get worse, not better, as anyone knows who’s been annoyed by a dripping kitchen faucet. The only problem here is that this faucet is “dripping” at upwards of 25,000 barrels per day. One industry source, who has knowledge of the operations, said, “[the BOP] isn’t closed and In my professional opinion, its not going to close…”

The well has now been flowing uncontrolled for 13 days. As we’ve talked about before, these units are designed to slam shut, not be flowed through, at least at these high rates and pressures. Erosion of the ram faces and the bore is now likely severe, further reducing its chances of ever actually shutting the well in and sealing.

I understand that preparations are now being made to cut the riser above the BOP in preparation of installing the containment structure to control the flow of oil. Essentially, it is a large structure that is lowered over the source of the leak, attached by a riser to the surface. Oil will then flow up the riser to a ship that will process and collect the oil. It is believed that, if successful, this structure could capture 85% of the produced oil. This is a technique that has been used successfully in shallow water, but never this deep. It appears to me that the containment structure is the only chance BP has of slowing the growth of the spill, at least until they get the well killed by a relief well, or if well bore damage slows the flow by itself.

The best comparison of this accident is not the Exxon Valdex but the largest accident ever, the Ixtoc I spill. (The largest spill was deliberately set by Saddam Hussein.)

On June 3, 1979, the 2 mile deep exploratory well, IXTOC I, blew out in the Bahia de Campeche, 600 miles south of Texas in the Gulf of Mexico. The IXTOC I was being drilled by the SEDCO 135, a semi-submersible platform on lease to Petroleos Mexicanos (PEMEX). A loss of drilling mud circulation caused the blowout to occur. The oil and gas blowing out of the well ignited, causing the platform to catch fire. The burning platform collapsed into the wellhead area hindering any immediate attempts to control the blowout. PEMEX hired blowout control experts and other spill control experts including Red Adair, Martech International of Houston, and the Mexican diving company, Daivaz. The Martech response included 50 personnel on site, the remotely operated vehicle TREC, and the submersible Pioneer I. The TREC attempted to find a safe approach to the Blowout Preventer (BOP). The approach was complicated by poor visibility and debris on the seafloor including derrick wreckage and 3000 meters of drilling pipe. Divers were eventually able to reach and activate the BOP, but the pressure of the oil and gas caused the valves to begin rupturing. The BOP was reopened to prevent destroying it. Two relief wells were drilled to relieve pressure from the well to allow response personnel to cap it. Norwegian experts were contracted to bring in skimming equipment and containment booms, and to begin cleanup of the spilled oil. The IXTOC I well continued to spill oil at a rate of 10,000 – 30,000 barrels per day until it was finally capped on March 23, 1980. Keyword: Boom, Corexit 9527, skimmer, manual removal, volunteers, blowout, fire, evaporation, blowout preventer, relief well, submersible..

Prevailing northerly currents in the western Gulf of Mexico carried spilled oil
toward the U.S. A 60-mile by 70-mile patch of sheen containing a 300 foot by
500 foot patch of heavy crude moved toward the Texas coast. On August 6, 1979,
tarballs from the spill impacted a 17 mile stretch of Texas beach. Mousse
patches impacted the shoreline north of Port Mansfield Channel on August 15 and
again on August 18. On August 24, mousse impacted shoreline south of Aransas
Pass. By August 26, most of North Padre Island was covered with moderate
amounts of oil.

As of September 1, all of the south Texas coast had been impacted by oil. A
storm lasting from September 13-15 removed the majority of the oil. For the
remainder of the response and subsequent study period (through August 1980) only
tarmats were observed on the beaches. Some oil escaped around boom barriers
protecting the three major inlets. During the September storm, there was
washing of oil over the Barrier Islands. Impacts to the estuaries were minor.

The similarity between the two spills is striking but there’s a key difference. Ixtoc had human divers while Deepwater Horizon used robots which couldn’t activate the BOP like Ixtoc. The initial BOP failure is stiking. The collar on the pipes kept the shears from severing the pipes in the blowout protector. Note how long it took to cap the well, from June 3, 1979 to March 23, 1980. The flow rate is similar to some estimates of Deepwater Horizon, 10,000 to 15,000 barrels per day. From an engineering perspective this is striking. There’s a single point of failure and no backup plan if the BOP fails. I’ve seen failure rates as high as 50% for the BOPs. Why we even do deepwater drilling is beyond me. The President should re-institute the moratorium on offshore drilling.

13 comments to The Deepwater Horizon Disaster

  • Richard Blinne

    The oil slick is nearing the loop current which means it could end up as far north as Virginia Beach. Drill baby drill.

  • Richard Blinne

    Here’s some more from the Washington Post on how BP avoided environmental regulations. Note what they said even though their own plan showed a maximum rate of 126,000 bbl/day.

    “;…the prospect of an oil spill “unlikely,” stated that “no mitigation measures other than those required by regulation and BP policy will be employed to avoid, diminish or eliminate potential impacts on environmental resources.”

    Even with a “categorical exclusion”  from the National Environmental Policy Act (NEPA), BP was asking for even more favors as late as 11 days before the spill. Given the huge disconnect between BP’s predictions and reality should they be trusted in their other operations?

  • Richard Blinne

    Here’s some more from the Washington Post on how BP avoided environmental regulations. Note what they said even though their own  plan showed a maximum rate of 126,000 bbl/day.
    “;…the prospect of an oil spill “unlikely,” stated that ‘no mitigation measures other than those required by regulation and BP policy will be employed to avoid, diminish or eliminate potential impacts on environmental resources.’”
    Even with a “categorical exclusion”  from the National Environmental Policy Act (NEPA), BP was asking for even more favors as late as 11 days before the spill. Given the huge disconnect between BP’s predictions and reality should they be trusted in their other operations?

  • Richard Blinne

    Randy mentioned to me about how people like Sean Hannity have been critical of the government’s response to the crisis. Here’s an excellent site set up by NOAA on the emergency response. (NOAA’s OR&R office takes the lead amongst the various agencies in oil spill mitigation.) The easy to remember web site is:

  • Wayne Dawson

    Maybe to keep this more in line with the lesson we might accept from it, Proverbs 15:24 say

    Folly delights a man who lacks judgment, but a man of understanding keeps a straight course.

    What is troubling is the lack of forethought about the consequences. First the people who died a horrible death on the rig because there were very few back up plans to shut down the source quickly in the case of an emergency. Second, the enormous loss of property and reputation for a company and its employees because someone somewhere didn’t make back up plans a significant priority. Third, we observe the destruction of a marine environment, a source of food and a source of livelihood for many people, all because back up plans were not high on the priority list.

    There is another thing too. It is we who want that oil. It is we who complain about the price of oil. If there was no demand for the oil, there would be no drilling or talk thereof.

    So as we reflect on the word folly, we should not forget that we all share a contribution to it.

    by Grace we proceed,

  • Richard Blinne

    It looks like the loop current possibility is now less. Here’s the forecast on this from Dr. Jeff Masters:

    A major concern with the Deepwater Horizon oil spill is the possibility for the oil to move southwards and become entrained into the mighty Gulf of Mexico Loop Current, which would rapidly transport the oil through the Florida Keys, impacting northwest Cuba, South Florida, the western Bahamas, and the U.S. East Coast all the way to Cape Hatteras, North Carolina. However, there is no immediate danger of this happening. The latest forecast of Gulf currents from the NOAA HYCOM model (see also this alternative view of the HYCOM ocean current forecast) indicate that the currents will not be favorable for pulling any oil southwards into the Loop Current over the next five days. Oil will have to travel approximately 100 miles to the south-southeast to get entrained into the Loop Current, and we probably would need a 2+ day period of strong winds out of the north for this to happen. The long-range GFS model indicates that the earliest this might happen is 10+ days from now. As summer gets closer, the incidence of cold fronts making it far enough south to bring an extended period of offshore northerly winds to the Gulf of Mexico decreases. I think there is a 40% chance that the next cold front capable of pushing oil into the Loop Current will arrive by the end of June. However, I think it is more likely that the next such front will not arrive until October, when fall comes.

    That makes a tropical storm or hurricane as perhaps the most likely weather event to push oil into the Loop Current over the next few months. A tropical storm hitting the Panhandle of Florida would do the trick, by bringing northerly winds over the oil spill location, thanks to the counter-clockwise flow of air around the storm. Looking ahead to June, June tropical storms tend to form in the Gulf of Mexico, and we’ve been averaging one June storm every two years since 1995. This year, the odds of a June Gulf of Mexico storm are probably a little lower than usual. While Gulf of Mexico sea surface temperatures are near average, wind shear from our lingering El Niño will probably be above average. Since 1995, there have been three June tropical storms in the Gulf of Mexico that have followed a track capable of pushing oil into the Loop Current. These storms were Hurricane Allison of 1995, Tropical Storm Allison of 2001, and Tropical Storm Arlene of 2005. Taking into account all these factors, I’ll give a 20% chance that we’ll get a June tropical storm capable of transporting oil into the Loop Current.

  • Richard Blinne

    Wayne there was a plan to stop the oil from being released It’s known as a blow out protector (BOP). The problem from an engineering perspective is this is a single catastrophic point of failure.  Since the BOP is a marvel of technology this fact didn’t really sink in. Furthermore, there appears to be a bad technology transfer from the shallower wells to the deeper ones. The BOP severs the pipes and this shuts off the oil. In deep waters these pipes are more difficult to cut since they have to operate at higher pressures.   This appears to be the failure when the backside blowout happened. The blowout itself seems to be related to when the pipe was hung off with a casing hanger and cemented by Halliburton. In fact, there is a large correlation between blowouts and this step at the end of the exploration phase of the well.

    There’s a word for all this. Hubris. Because nothing bad has happened then nothing bad will happen. A very tragic irony was right when the explosion happened there was a party with BP execs on the rig celebrating seven years of safety. Please don’t misread my tone in all this. This is very, very, difficult. Most of us don’t have jobs where a small mistake causes death and destruction. The question I have is this risk worth it when according to EIA drilling the OCS  would only cause a few cents a gallon decrease in the price of gasoline in the 2020s.

  • Richard Blinne

    The NY Times has an article on how the lack of a backup to the BOP has been a concern but not addressed because the regulators deferred to the industry:
    Questions about the blowout preventers — which BP executives have said are at least partly to blame for the April 22 accident — date back at least to February 2000, when a rig in the Gulf of Mexico spilled oil into the sea after a crew member accidentally pushed the wrong button, severing the connection between the rig and its blowout prevention device, known as a BOP.  [RDB Note: For this accident the well was already cased while the Deepwater Horizon was in the process of having this done. Thus, the difference in the magnitude of the crisis.]
    “The rig was not equipped with a secondary system capable of securing the well in the absence of the primary BOP controls,” said a federal report on the accident.
    To combat this serious safety flaw, the agency warned oil companies in 2000 and again in June 2009, after yet more problems emerged with a blowout preventer, reminding them that they needed to have “a reliable backup system in place.” But the agency never tried to draft regulations that would detail the requirements for the backup systems.
    Instead, more than a decade ago, with the support of the industry, the agency reduced the frequency of inspections of blowout preventers from once a week to once every 14 days, citing the disruptions that these tests caused to oil drilling and extraction efforts.
    In the absence of government regulations, all 23 of the oil drilling rigs currently working in the Gulf of Mexico rely on a backup device known as a remotely controlled submersible vehicle to turn on the blowout preventers if primary controls fail. That was the case with the Deepwater Horizon rig as well.
    But a consultant hired by the mineral service in 2003 warned that these machines were frequently unreliable during blowouts, moving too slowly and often lacking sufficient power to do the job.
    Worse, the same consultant concluded in a federally financed study that even if rig crews managed to turn the blowout preventer on, the most critical safety component inside these machines — the shear ram, which is meant to cut quickly through the well pipe to stop the flow of oil and gas — was often not strong enough to cut through the modern types of pipe that drilling rigs now use.

    Elsewhere around the world, the trend has been to split up agencies like Minerals and Management Service, separating the government officials who are responsible for overseeing natural resource extraction from those who are charged with ensuring its safety.
    For example, in 2005, Australia created a separate regulator — the National Offshore Petroleum Safety Authority, following the lead of Britain, which severed these functions after a 1988 oil rig explosion in the North Sea, known as the Piper Alpha incident, that killed 167 people.
    “It has to be that way,” said David Doig, the chief executive of an industry-owned nonprofit organization in Britain, the Offshore Petroleum Industry Training Organization. “You need to divorce operations monitoring from the integrity monitoring, because operations will always be the one driving behavior. They’re motivated by the need to keep things going, and the finances rolling.”

  • Richard Blinne

    We’re starting to get confirmation of what I have been saying from the mainstream press. Note this AP story this morning.

    “The deadly blowout of an oil rig in the Gulf of Mexico was triggered by a bubble of methane gas that escaped from the well and shot up the drill column, expanding quickly as it burst through several seals and barriers before exploding, according to interviews with rig workers conducted during BP’s internal investigation.

    While the cause of the explosion is still under investigation, the sequence of events described in the interviews provides the most detailed account of the April 20 blast that killed 11 workers and touched off the underwater gusher that has poured more than 3 million gallons of crude into the Gulf.”

    “Based on the interviews, Bea believes that the workers set and then tested a cement seal at the bottom of the well. Then they reduced the pressure in the drill column and attempted to set a second seal below the sea floor. A chemical reaction caused by the setting cement created heat and a gas bubble which destroyed the seal.” [RDB note: this confirms what I have been saying that this was a bad Halliburton casing job.]

    “A group of BP executives were on board the Deepwater Horizon rig celebrating the project’s safety record, according to the transcripts. Meanwhile, far below, the rig was being converted from an exploration well to a production well.” [RDB note: executives partying on rig confirmed.]

    Note these slides (cf. slide 14)  documenting the linkage between the BP-funded Consumer Energy Alliance and the Tea Party astroturf organization,  FreedomWorks, trying to promote OCS development.

    Speaking of FreedomWorks, note this speech by Lord Monckton (at 6:53 and 9:27)  at the Tax Day Tea Party in Washington D.C.  Look at the logo behind his shoulder. Lord Monckton is also invited to rallies sponsored by Massey Energy. Massey Energy is the company that had the fatal coal mining accident recently.

  • Richard Blinne

    Bob Cavner did some back of the envelope calculations from the methane hydrate clogging to conclude that the “official” 5,000 bbl/day rate is underscoped.

    “The speed in which the vessel clogged is yet another indicator to me that the flow of the well could be much higher than the reported 5,000 barrels per day.  The vessel, if my calcs are correct, holds about 2,400 barrels of liquid.  Assuming that it settled into the sea floor down to the “mud flaps” welded to the sides, that would cut capacity to about 1,200 barrels.  At 5,000 barrels per day flow, the vessel would fill in about 6 hours.  At 25,000 barrels per day, it would fill in just over an hour.  The velocity through the connection would be very high, setting up perfect conditions for rapid hydrate formation, which is exactly what happened.”

    He then concludes:

    “As this enviromental and technological disaster continues to unfold, it is becoming very clear that our technology to drill in these inhospitable locations has outstripped our ability to cope with the problems when something goes terribly wrong.  I have convinced myself that it’s time to step back from deepwater development with subsea facilities until we come up with a reliable way to keep these kinds of disasters from not only happening; but more importantly, knowing how to quickly cope with them when they do.”

    I agree. I see that kind of near-sightedness in the engineering environment where I work. When you are designing semiconductors in 65nm and above gate length, the worst case slow corner is at 125 degrees C. The problem is that as supply voltages drop below 1V in 40nm and smaller technologies the low temperature subthreshold current becomes an issue. This means your slow corner is now minus 40 C.  Or worse, sometimes it’s one temperature and sometimes the other. Early in the 40nm development, the analysis was done at the high temperature because the engineers didn’t realize the cold corner kills you.  Engineers use experience to guide them but when you go into discontinuities this “experience” might be harmful. It took some of us who were expecting crazy unknown problems jumping up and down and screaming to correct the issue. 

    This happened with the deepwater offshore drilling. The engineers there didn’t appreciate the chemical reactions of the methane ice with the concrete caps at the pressures and temperatures of a mile deep. We aren’t prophets. We just extend trends. And sometimes this gets us into trouble.

    Global warming deniers don’t appreciate the discontinuities that happen if we warm more than 3 degrees C. As James Hanson correctly puts it, it’s “another planet”. All bets are off on exactly what might happen and the current critique of computer models would be correct. Namely, we wouldn’t have a clue.

    Furthermore, it’s the same companies who are saying don’t worry about global warming that told us that offshore drilling was safe. Fool me once…

May 2010
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