Deep water, Black Horizon: Offshore drilling and the coming energy crisis

Published on Friday, 16 April 2010 12:54

By Robin Whitlock

On April 20th the Deepwater Horizon drilling rig in the Gulf of Mexico, 41 miles south of Louisiana, was rocked by a gigantic explosion, which seriously damaged the oil pipeline and sent a huge oil slick across the waters of the Gulf. It has quickly become one of the most serious oil disasters of modern times. It threatens to devastate not only the southern coast of the United States, along with much of the wildlife it supports, but also the livelihoods of many of the communities that live there.

There are three main aspects of this disaster that warrant further investigation. The first of these concerns the reliability of the equipment involved and whether or not the oil companies maintained competent safety procedures and maintenance programmes. The second concerns a rumour circulating among some oil industry experts that we are not being told the entire truth about the damage that has been done to the sea floor surrounding the wellhead. Finally, the third question is whether the current trend for deepwater offshore drilling, along with the possible risk taking and shortcuts taken by BP, indicate the imminent arrival of an energy crunch caused by oil depletion, known popularly as 'Peak Oil'.

As each week passes and still the estimates of just how much oil is leaking into the Gulf increase. These estimates are obtained from various sources, such as videos taken by submersible Remote Operating Vehicles (ROV's), Acoustic Doppler Current Profiler's (ADCP's) and measurements of oil collected by surface ships.[1] At first it was thought the well was releasing around 18,000 barrels of oil per day (bpd). Then estimates were revised upwards to reach somewhere between 35,000 and 60,000 bpd. The latest findings have again raised that figure. The current estimate is 100,000 bpd.

It's been interesting trying to keep up to date with developments on this story since the situation seems to have changed almost every day judging by the multitude of news stories in papers, on TV and on the Internet. Some of these have been little more than rumour, others more plausible, but the general picture is nevertheless most alarming and threatens to worsen with the oncoming hurricane season. The first question to be asked is what caused this emergency in the first place?

It appears from an internal investigation carried out by BP that the cause of the explosion may have been a bubble of methane gas, which escaped from the well. This bubble then rose to the surface through the drilling column, breaking through several seals in the process and then emerging onto the rig. The gas entered a number of rooms where there were a number of exposed ignition sources, which then caused the gas to explode.

Excerpts from interviews with rig workers conducted during the inquiry were conveyed to Professor Robert Bea, an engineering professor from the University of California Berkeley who serves on a National Academy of Engineering panel on oil pipeline safety and who worked for BP as a risk assessment consultant during the 1990s. Bea believes that the workers set and tested a concrete seal at the bottom of the well. They then reduced the pressure in the drill column and prepared to set a second seal on the sea floor. While they were engaged in preparing the second seal, a chemical reaction within the concrete of the first seal caused a gas bubble to form, which destroyed the seal before rising up the drill column. The initial explosion ignited the oil that had risen up the column behind the methane gas.[2]

In learning about blowouts I have discovered that there are a number of built in safety measures on drilling rigs designed to prevent such disasters. Within the well hole that descends to the well through the rock beneath the sea floor there is a pipe within which the drilling column is set. This pipe is sealed with synthetic mud and cement in order to block any space through which gas can escape to the surface.

As an additional measure, a device called a blowout preventer (BOP) sits on the seabed around the well hole. The BOP is a massive mechanical contraption, which works by squeezing rubber seals around the drilling column with a force of around one million pounds per square inch. If these seals fail then the BOP deploys a number of rams, which slice through the pipe and cap the blowout. On the Deepwater Horizon an automated device called a 'Deadman' was in place the function of which was to operate the BOP if the rig workers for some reason failed to do so.

Interviews with the rig workers appear to have discovered that none of these safeguards worked.[3] Rig workers employed by Transocean, one of the two companies that operated the Deepwater Horizon alongside BP, revealed that attempts to operate the BOP continued up until the point of the explosion and fire necessitated the evacuation of the rig. It seems also that BP workers attempted to use submersible Remote Operated Vehicles (ROV's) to close various 'subsea access points' on the BOP in order to operate it and close down the well, but these attempts also failed.[4]

A letter to BP Chief Executive Tony Hayward written by Representative Bart Stupak and Chairman Henry Waxman of the House Subcommittee on Oversight and Investigations, claims that BP took unnecessary and risky shortcuts in its drilling procedures prior to the explosion.[5] A BP drilling engineer for instance referred to the Deepwater site as a 'nightmare well'[6] while a government hearing in Louisiana discovered that the rig crew noticed unusual pressure readings coming from the wellhead in the hours leading up to the disaster.[7] After examining a number of BP documents US Congressional investigators have concluded that the BOP was faulty, suffering from a hydraulic leak and a failed battery. In the course of its enquiry the House Subcommittee has referred to a 2001 report revealing that the BOP may have suffered as many as 260 possible equipment failures.[8]

All this makes it look as if BP has been guilty of some serious breaches of safety standards over the years. I spoke to a former oil industry geologist who has worked on rigs both in the North Sea and in the Gulf in years past. In the course of various conversations about the Deepwater Horizon he put across his own particular perspective on the issue of safety and who is ultimately responsible. For obvious reasons he wishes to remain anonymous, however in a comment I made concerning reports that a neighbouring platform, the Atlantis, was said to be even worse condition than the Deepwater Horizon he implied that this was probably true.

"I've heard about it,” he tells me. "Thing is there's a culture of sailing close to the wind when it comes to safety in the Gulf. When I was out there I demanded to leave the rig I was on for those very reasons, the only time I've ever done so. In my opinion, the Atlantis has been cutting corners on safety but so far all the operations have been fine and there's been no major incident or spillage. Finally these corner-cuttings are coming to light and Obama will tighten up regulations, and blame BP of course."

I asked him if this kind of thing is unique to a particular field in a particular region of the world?

He replied. "Sorry to burst the bubble on that one, I'd say that a certain leading country in the modern world, has the worst safety levels in developed countries but many LEDC's (least economically developed countries) have some real seat-of-pants operations going. There have been some pretty terrible disasters in places like Nigeria, but hey the fishermen and other people who lost their livelihoods out there are dispensable, and no one really cares about them? Hence hardly any media coverage."

I switch the conversation over to the subject of shortcuts. "Old equipment" I am told, "means less checks on stuff that contain high pressures, no regulation on pollution, less well-trained staff, and in many countries drug abuse at work.

So, given that the oil companies would naturally be willing to cover up such practices, or at least repair the damage once they become apparent, you would think they would pull out all the stops to plug the leak as quickly as possible. Why is it then that attempts to do so have so far failed?

For a start the wellhead is 5000 feet beneath the surface. Procedures designed to close down leaks have not been attempted at such a depth before. When the rig sunk, the riser, the pipe that connects a rig to its wellhead, buckled and twisted leaving kinks in the pipe.[9] BP is drilling a relief well, but this could take three months or more to be completed and it is subject to the risks presented by equipment failure and bad weather. BP tried to cap the leak with a containment dome, but this failed because ice crystals, called hydrates, formed at the top and clogged the pipe that was to carry the oil up to the surface. The hydrates also gave the containment dome a level of buoyancy that prevented the formation of an effective seal around the wellhead.

Another option would have been to cut the riser pipe and feed it into another pipe leading to the surface ship. This procedure is risky because if something goes wrong then potentially more oil, not less, could spill out onto the surface. Then there is what is known as a 'junk shot’, which involves the plugging of the pipe with solid, rubbery and fibrous material. This would only be temporary giving engineers time to prepare a permanent plug of cement.[10] All these procedures, with the exception of drilling relief wells, which appears to be the option that BP is now relying on, have failed.

The effects of the spill upon the waters of the Gulf of Mexico and the coastal communities of the southern United States have already been catastrophic. The oil is beginning to reach floating nurseries of Sargassum seaweed where the larvae of at least 120 species of offshore fish are raised. These waters are also important feeding grounds for the Whale Shark, essentially the world's largest fish.[11] Figures from the 9th June relating to the effect on sea turtles report 320 specimens found dead or injured with 32 rescued. The Gulf is home to five of the world's seven species of sea turtle all of which are listed under the US Endangered Species Act as 'threatened' or 'endangered'.[12] The oil spill has additionally caused the haul of blue crab, oyster and finned fish by coastal fishing communities to be cut by half as areas likely to be affected have been closed by Federal authorities. The normal shrimp haul has been cut by a quarter. Around 27,000 jobs are under threat.[13]

The full extent of the damage to the well and the resulting spill of oil into the sea may not be apparent for some time. On 10th June Russian reports from the Kremlin, to the effect that the sea floor around the well had been fractured beyond repair, were mentioned in a feature by the US media watch website Before Its News.[14] At first I thought this was conspiracy theory and exaggeration but I checked it out by browsing for similar reports elsewhere on the Internet. As a result I discovered a televised report on the US news programme MSM posted on YouTube.[15] The report included a statement by Florida senator Bill Nelson in which he claimed that he had received reports of oil seeping up directly from the seabed. This would indicate that the well casing had been pierced below the sea floor allowing the oil to gush into the surrounding rock and presumably escaping through faults in the rock strata. Such reports had also been referred to in stories carried by The Washington Post and The New York Times.[16]

The MSM report continued with an interview with oil industry expert Bob Cavar who stated his belief that an 'underground blowout' is highly likely and that this probably occurred during the attempts by BP to seal the well by pumping cement and synthetic mud into it to seal it, a procedure known as 'top kill'. Cavar believes this may have damaged the casing below the sea floor. He believes that BP's subsequent approach of capping the BOP is an indication of an underground blowout since continuing the top kill approach would make the leak of oil through the casing even worse because of the pressure applied to the well shaft. Cavar stresses that this increases the importance of drilling relief wells to relieve the pressure but warns that if the oil is indeed leaking right through the various layers of the oil pipe, which consists of concentric casing, into the surrounding rock structure, then it's a "doomsday scenario", an open flow, and that the only way of stopping it would be through the relief wells which will take some time to put in place.[17]

I wondered what Cavar meant by "doomsday scenario" so I investigated further and encountered another YouTube posted interview, this time with oil expert Matt Simmons on MS: NBC News The Dylan Rattigan Show.[18] Simmons said that as a result of discussions with colleagues he concluded that the oil had to be escaping the well at reservoir pressure of 40 to 50 thousand pounds per square inch and that there had to be a daily escape of 100 to 150 thousand barrels of oil. He further stated his belief that the well was now an 'open hole' with no casing in it and that the only way in which to fix it was to either let it deplete, which would take about 30 years and poison the Gulf of Mexico if not the entire Atlantic Ocean, or to put a nuclear device down the hole and encase the spill by turning the rock into glass, which, Simmons stated, was what the Russians had done when dealing with their land-based underground blowouts.

I blinked, not quite believing what I had just heard. However, I discovered that Simmons wasn't the only industry expert recommending the nuclear option. Michael E. Webber, a mechanical engineer from the University of Texas at Austin is also recommending this option, as is Christopher Brownfield from the University of Columbia. The White House, so far, has however rejected this idea if only on the basis that this option was exercised by the Russians on land rather than at the bottom of the sea.[19] Even now, as this article goes to press, the news gets worse. The Federal Emergency Management Agency (FEMA) and the US Army Corps of Engineers have reported that there is effectively a "dead zone" within a 200 miles radius from the site of the disaster. BP, Corexit9500, which has apparently mixed with evaporated seawater and absorbed into rain clouds, which will subsequently produce toxic rain, partly due to the chemical dispersant uses this. This is in addition to the large amounts of methane that have been reported bubbling up from the well. There are reports, which may also be in response to the looming Hurricane Gustav, that plans for mandatory evacuation of coastal communities are being put in place, to include population centres such as New Orleans, Biloxi, Baton Rouge and Pensacola. FEMA sources have estimated a final compensation bill as standing at somewhere near $2-3 trillion dollars.[20]

The whole episode is, I believe, relevant to and may be an indication of another issue, which has been of growing concern to the oil industry and to world governments over recent years - peak oil. More easily understood as energy depletion, the concern about peak oil focuses on the growing gap between demand for oil, which is essential for the maintenance of our modern growth economy, and the ability of the oil companies to supply it. This must be understood correctly. The world is not running out of oil, it is running out of easily accessible oil, which means that production costs are increasing in proportion to the wealth that the recovered oil creates. Left to itself, this process has the ability to inflict severe economic hardship on the world's economies and, at worst case scenario, if ignored will eventually cause an economic depression from which, unlike that of 1929, the world will not recover.

There is considerable controversy among oil industry executives, economists, geologists and other experts about just when global oil production will peak, although some of them say it has peaked already. The tendency to drill in ever deeper waters may indeed be a sign that the peak is not far away. William Rees-Mogg writing in The Daily Mail recently made this exact point. "The Gulf of Mexico spillage reflects the risk of pushing oil exploration to the limit of technology 5000 ft below the sea's surface" he states. "Nobody would be looking for oil at 5000ft if there were new supplies in shallower waters". Rees-Mogg goes on to report that the price of Brent Crude reached $74 per barrel at the beginning of June and suggests that the rise in price has been a measure of the growth in demand and the simultaneous failure to meet that demand. His conclusion is simple and blunt; the age of easily available oil is over.

I've been thinking about this all along. As a result I've picked back up the book by Jeremy Leggett that I abandoned half way through before starting university in 2005. Its title is poignant and I believe accurate "Half Gone: Oil, Gas, Hot Air and the Global Energy Crisis".[21]

Leggett makes some startling conclusions in this book, for instance he repeats long held suspicions that certain OPEC countries, particularly Saudi Arabia, have been economical with the truth regarding the state of their oil reserves, furthermore he cites the example of the Shell oil scandal as evidence of the oil industry's tendency to hide the truth about global oil reserves. Throughout the book he indicates that every supply crisis thus far, those in 1973 and 1980-81, for example, has been followed by a recession. Other energy analysts talking about peak oil, including and perhaps most notably Matt Simmons, claim that if this issue is ignored the recession that follows the next energy crunch may be a global recession from which we will not recover. Alarmingly Jeremy Leggett suggests that this 'topping point' or 'peak' of the oil production curve is very near at hand, he even implicitly gives a date at which it may occur - 2015.

If that's true, the Deepwater Horizon was well named. For if we don't wean our society off oil soon, then we will literally be in deep water, with a black horizon ahead.

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* Statements and quotations used in this article are the opinions of individuals and not that of Ask The Experts. All information presented in this article is researched and is to the best of the authors knowledge, accurate and true.