As someone who worked as a helicopter pilot in the oil support industry for 13 years, and as someone who drives a gasoline-powered car, I have come to view the domestic oil industry in the Gulf of Mexico as “pretty safe,” environmentally. Well that’s all changed now with the explosion and sinking of a drilling rig called the Deepwater Horizon that was owned by a company called Transocean LTD and working for British Petroleum (BP).
A quick word about oil production: Normally, you drill a hole in the ground and find the oil. A drilling rig performs this action. Then a “jacket” is placed over the wellhead(s). On this “jacket” will be certain equipment to process and clean the oil to a certain standard before it can be sent into the pipeline to the refinery. Out in the Gulf of Mexico, this process is complicated by the fact that the rigs cannot sit on the seafloor, and it must drill down through water. Holding the rig in an exact position is tricky, depending on the depth of the water. There are various ways to do it.
Transocean's Deepwater Horizon was a semi-submersible drilling rig. The rig structure itself was mounted on huge pontoons which provided flotation as it was towed to the desired location. Once on-site, the pontoons are filled with water, sinking the rig to a predetermined level and stabilizing it in the water. Huge anchor cables fan out from each corner to the seafloor, positively securing the whole mess in one place. “Semis” can drill in incredibly deep water, down to about 10,000 feet.
A quick word about oil production: Normally, you drill a hole in the ground and find the oil. A drilling rig performs this action. Then a “jacket” is placed over the wellhead(s). On this “jacket” will be certain equipment to process and clean the oil to a certain standard before it can be sent into the pipeline to the refinery. Out in the Gulf of Mexico, this process is complicated by the fact that the rigs cannot sit on the seafloor, and it must drill down through water. Holding the rig in an exact position is tricky, depending on the depth of the water. There are various ways to do it.
Transocean's Deepwater Horizon was a semi-submersible drilling rig. The rig structure itself was mounted on huge pontoons which provided flotation as it was towed to the desired location. Once on-site, the pontoons are filled with water, sinking the rig to a predetermined level and stabilizing it in the water. Huge anchor cables fan out from each corner to the seafloor, positively securing the whole mess in one place. “Semis” can drill in incredibly deep water, down to about 10,000 feet.
Above: An example of a semi-submersible rig. Pumping water into the legs will sink the rig down to where the legs turn from gray to orange. 
Above: This is the Deepwater Nautilus, the same type and size of rig as the Horizon. It is being transported on a ship (a huge ship!), and the underwater pontoons can clearly be seen.
The Deepwater Horizon was operating in 5,000 feet of water, just beyond what we call the “shelf” in the Gulf of Mexico, where the shallow seafloor near the shoreline suddenly drops off a cliff.
There are supposed to be all sorts of safety devices to prevent the accidental spillage of oil. But that’s difficult when the primary purpose of your equipment is to drill a hole in the ground and you don’t know when/if you’re going to find oil. If the spinning drill-pipe is compromised, the automatic subsurface safety valve (SSSV) might not work. Which is what happened when the Deepwater Horizon blew up on April 10th and subsequently sank.
As I write this, BP is using remote-operated vehicles (ROV’s) in an attempt to manually close the SSSVs. Until they do, and even if they can, uncontained oil flows from the wells at the rate of 42,000 gallons per day. This oil rises to the surface where it forms a big slick. The location of the Deepwater Horizon was just south and east of the mouth of the Mississippi River. What this means is that if the oil slick drifts to the north, it will most likely affect the swampy shoreline of southeast Louisiana, as well as the beaches of Mississippi, Alabama and Florida. Needless to say, plenty of folks are worried, from environmentalists to those involved in the tourist industry. As you might expect, here in Pensacola we are watching this with particular interest as we could be in the line of fire. It might not be as bad as the Exxon Valdez spill, but it could be a disaster nonetheless for the gulf coast.
If ever there were a worst-case scenario for semi-submersible rigs this is it. BP is blaming Transocean, and to no one's surprise Transocean is blaming BP.
It goes without saying that the best and the brightest minds are looking for ways of containing this oil – not just the stuff on the surface but the oil that is still coming out of the wells at the seafloor level. BP has theorized that they might be able to invent and build some sort of capture device that they could put over the wellheads, and then suck the oil up to awaiting storage/tanker ships on the surface. Trouble is, this has never been tried before. If it worked, it would give them time to drill another, adjacent well so they could then tap into the existing well and seal it off. It gets complicated to explain.
The U.S. Coast Guard is attempting to corral oil at the surface and set fire to it. This actually has been done before, so we’ll see how well it works this time.
All of this leaves me more than a little ambivalent. There are those who call for more drilling in the U.S. in order to end or at least reduce our “dependency” on foreign oil. Me, I’m not so sure. As “safe” as you make something (and BP has a reputation for being one of the most safety-conscious oil companies in the Gulf of Mexico), accidents can and do happen, as we found out on April 10, 2010. We are dependant on cars powered by internal-combustion engines that run on gasoline. This simply will not change much in the near future. Thus, we are necessarily tied to the petroleum industry. For good and for bad.
And as for the mess with the Deepwater Horizon, this is bad.
There are supposed to be all sorts of safety devices to prevent the accidental spillage of oil. But that’s difficult when the primary purpose of your equipment is to drill a hole in the ground and you don’t know when/if you’re going to find oil. If the spinning drill-pipe is compromised, the automatic subsurface safety valve (SSSV) might not work. Which is what happened when the Deepwater Horizon blew up on April 10th and subsequently sank.
As I write this, BP is using remote-operated vehicles (ROV’s) in an attempt to manually close the SSSVs. Until they do, and even if they can, uncontained oil flows from the wells at the rate of 42,000 gallons per day. This oil rises to the surface where it forms a big slick. The location of the Deepwater Horizon was just south and east of the mouth of the Mississippi River. What this means is that if the oil slick drifts to the north, it will most likely affect the swampy shoreline of southeast Louisiana, as well as the beaches of Mississippi, Alabama and Florida. Needless to say, plenty of folks are worried, from environmentalists to those involved in the tourist industry. As you might expect, here in Pensacola we are watching this with particular interest as we could be in the line of fire. It might not be as bad as the Exxon Valdez spill, but it could be a disaster nonetheless for the gulf coast.
If ever there were a worst-case scenario for semi-submersible rigs this is it. BP is blaming Transocean, and to no one's surprise Transocean is blaming BP.
It goes without saying that the best and the brightest minds are looking for ways of containing this oil – not just the stuff on the surface but the oil that is still coming out of the wells at the seafloor level. BP has theorized that they might be able to invent and build some sort of capture device that they could put over the wellheads, and then suck the oil up to awaiting storage/tanker ships on the surface. Trouble is, this has never been tried before. If it worked, it would give them time to drill another, adjacent well so they could then tap into the existing well and seal it off. It gets complicated to explain.
The U.S. Coast Guard is attempting to corral oil at the surface and set fire to it. This actually has been done before, so we’ll see how well it works this time.
All of this leaves me more than a little ambivalent. There are those who call for more drilling in the U.S. in order to end or at least reduce our “dependency” on foreign oil. Me, I’m not so sure. As “safe” as you make something (and BP has a reputation for being one of the most safety-conscious oil companies in the Gulf of Mexico), accidents can and do happen, as we found out on April 10, 2010. We are dependant on cars powered by internal-combustion engines that run on gasoline. This simply will not change much in the near future. Thus, we are necessarily tied to the petroleum industry. For good and for bad.
And as for the mess with the Deepwater Horizon, this is bad.
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