The Gulf spill could end up dumping the equivalent of 4 Exxon Valdez spills per week.
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The Wall Street Journal reports that the well lacked a remote-control shut-off switch that is required by Brazil and Norway, two other major oil-producing nations.

Experts have said that the remote-control switch may have been able to shut off the Deepwater Horizon well, and critics of have said the lack of the remote control is a sign U.S. authorities have been too lax with the industry.

NWS forecast for oil spill spread in Gulf of Mexico as of May 3, 2010. Click on any of the pictures here to enlarge.

The worst-case scenario for the broken and leaking well gushing oil into the Gulf of Mexico would be the loss of the wellhead currently restricting the flow to 5,000 barrels — or 210,000 gallons per day.

If the wellhead is lost, oil could leave the well at a much greater rate, perhaps up to 150,000 barrels — or more than 6 million gallons per day — based on government data showing daily production at another deepwater Gulf well.

By comparison, the Exxon Valdez spill was 11 million gallons total. The Gulf spill could end up dumping the equivalent of 4 Exxon Valdez spills per week. (al.com)

And no one knows for certain how or when they can shut down the flow.

In this aerial photo taken in the Gulf of Mexico more than 50 miles southeast of Venice on Louisiana's tip, the Deepwater Horizon oil rig is seen burning Wednesday, April 21, 2010. (AP Photo/Gerald Herbert)

The [Deepwater Horizon] platform exploded on April 20 and sank two days later, leaving 11 workers missing and presumed dead, and producing one of the largest oil spills in history in U.S. water.

Soon after the explosion and sinking of the platform, which houses the machinery used to extract oil from the ocean floor through a hole called an oil well, the New York Times reported that federal authorities have recorded more than 500 fires on oil platforms, two deaths and 12 serious injuries due to platform fires in the Gulf of Mexico since 2006. None of the accidents has slowed the rate of drilling in the Gulf, which has increased over the past decade. In the aftermath of the explosion, industry officials said that despite the loss of the Deepwater Horizon, drilling in the Gulf will likely continue as usual.

MMS is currently investigating a whistleblower’s claims that BP had broken the law by not keeping an up-to-date set of records on the oil platform Atlantis, also located in the Gulf of Mexico. In the event of an emergency, such records would be vital to shut down the platform. According to an email from a BP executive, not having the records could lead to “catastrophic operator errors.” Atlantis, which is located 190 miles south of New Orleans, is the largest oil platform of any kind in the world. (whistleblower.org)

This image provided by the U.S. Coast Guard Saturday April 24, 2010 shows oil leaking from the drill pipe of the Deepwater Horizon drilling rig after it sank Thursday. (AP photo/US Coast Guard)

Kinks in the piping created as the rig sank to the seafloor may be all that is preventing the Deepwater Horizon well from releasing its maximum flow. BP is now drilling a relief well as the ultimate fix. The company said Thursday that process would take up to 3 months.

Diagram of what is going on beneath the oil slick

Sand is an integral part of the formations that hold oil under the Gulf. That sand, carried in the oil as it shoots through the piping, is blamed for the ongoing erosion described by BP.

“The pipe could disintegrate. You’ve got sand getting into the pipe, its eroding the pipe all the time, like a sandblaster,” said Ron Gouget, a former oil spill response coordinator for the National Oceanic and Atmospheric Administration.

“When the oil is removed normally, it comes out at a controlled rate. You can still have abrasive particles in that. Well, now, at this well, its coming out at fairly high velocity,” Gouget continued. “Any erosive grains are abrading the inside of the pipe and all the steel that comes in contact with the liquid. It’s essentially sanding away the pipe.”

An April 25, 2010 satellite photo provided by NASA shows a portion of an oil slick in the Gulf of Mexico, with ships visible at bottom left. (AP Photo/via NASA)

The formation that was being drilled by the Deepwater Horizon when it exploded and sank last week is reported to have tens of millions of barrels of oil. A barrel contains 42 gallons.

“The loss of a wellhead, this is totally unprecedented,” said Gouget. “How bad it could get from that, you will have a tremendous volume of oil that is going to be offgassing on the coast. Depending on how much wind is there, and how those gases build up, that’s a significant health concern.” (al.com)

The growing oil slick in the Gulf of Mexico is captured in this image from NASA's (MODIS) instrument aboard the Terra satellite. This natural-color image acquired April 29, 2010 shows a twisting patch of oil nearly 125 km (78 mi) wide. (NASA Earth Observatory/Jesse Allen/University of Wisconsin SSEC

A publicly available Halliburton PowerPoint presentation from last November might tell us a lot about what could have caused the oil blowout, fire and massive oil gushing at the Horizon rig.

Suppose you’re that division of Halliburton that has the dangerous job of “cementing” the drilling hole and the gaps between the hole and pipe. You’ve done this lots of times in shallow water wells, but you’ve learned through previous experience in deep water there’s a particularly difficult problem having to do with the presence of gas that has seeped to the ocean floor and been captured in essentially “frozen” crystallized formations.

The problem is that when you drill into these formations, and then try to inject cement into the hole/gaps to prevent leakage, the curing process for that creates heat. That heat can, if not controlled, cause the gas to escape the frozen crystals. If a lot of gas is released all at once, as could happen during the cement/curing process, it can cause a blowout where the cementing is occurring, or force gas and/or oil up the pipeline to the drilling rig on the surface. And the heat created by the process may be just enough to ignite the gas, causing the explosion and fire.

Did this happen at the Horizon rig? And if Halliburton already knew about this problem months (years) ago, and knew the risks it might create, why are we just now learning about this?

From Halliburton’s presentation (large pdf), page 10, last November (my bold):

Challenges

• Shallow water flow may occur during or after cement job
Under water blow out has happened
• Gas flow may occur after a cement job in deepwater environments that contain major hydrate zones.
• Destabilization of hydrates after the cement job is confirmed by downhole cameras.
• The gas flow could slow down in hours to days if the de- stabilization is not severe.
• However, the consequences could be more severe in worse cases.

Page 13 lists the design objectives but then concedes they can’t all be met at once:

Deepwater Well Objectives
• Cement slurry should be placed in the entire annulus with no losses
• Temperature increase during slurry hydration should not destabilize hydrates
• There should be no influx of shallow water or gas into the annulus
• The cement slurry should develop strength in the shortest time after placement
Conditions in deepwater wells are not
conducive to achieving all of these
objectives simultaneously

The presentation goes on to explain various options for dealing with the risks and assess the relative merits and costs. What’s interesting is that Halliburton appears to have been working at the edge of the technology and was not certain what would happen. Most experience was in shallower waters and no one was certain what would happen in deep waters. It conducted tests, but it’s not clear how complete or realistic those tests were or how costs factored into the choice of techniques. (FDL Scarecrow)

Those negotiating deep water drilling contracts in Africa should take this to heart. One thing that should be possible is that a remote shut off should be a requirement in any deepwater drilling contract, though I’m not holding my breath. You cannot depend on the oil companies to police themselves, or even to make realistic assessments of the dangers and potential costs, particularly if they are not likely to pay much of those costs. We have the Niger Delta to remind us just how civic minded the oil companies can be, and how well leadership has stood up for the governed in dealing with the oil companies. The US has unleashed this monster upon itself because it has confused the corporate predator state with democracy, and governs more despite the people than for the people.

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See more amazing photos from the Boston Globe, including the photos posted here.

See more maps and photos at the US Coast Guard Deep Horizon Flickr photo stream.

See the larger satellite view of the last picture above of the Gulf coastline.

The Oil Drum has some good explanation and informed speculation as to what happened: Tech Talk: Revisiting Oil Well Pressures and Blowout Preventers after BP’s Oil Spill.

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This post is continued in Oil Spilling In The Ocean Currents and Into Coastal Wetlands