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Thursday, February 3, 2011

The Santa Barbara Oil Spill: Could it happen again? (published in June of 2010 in the SB News Press)

At 10:45 A.M. on Tuesday morning, January 28, 1969, about six miles off the coast of Summerland, in the Dos Cuadras Offshore Oil Field, Union Oil’s “Platform Alpha, or Platform A” had a blow out.  Over a ten-day period, an estimated 80,000 to 100,000 barrels of crude oil spilled into the channel and onto the beaches of Santa Barbara County, fouling the coastline from Goleta to the Rincon and all four of the northern Channel Islands. Upward of 10,000 birds were killed in the ecological disaster. Eight hundred square miles of ocean were impacted, and 35 miles of coastline were coated with oil up to six inches thick.

There were also a large number of poisoned seals and dolphins as well as innumerable fish and intertidal invertebrates, devastated kelp forests, and many displaced populations of endangered birds.  (Just to compare, an estimated 35,000 to 60,000 barrels are leaking from the BP spill each day.)  With the recent BP spill in the Gulf of Mexico, many are asking; could another spill occur here? 

In this week’s column, I will review the causes of the 1069 spill, and make a few more comparisons to the BP oil spill, in an attempt to determine the likelihood of another, similar spill occurring in the Santa Barbara Channel.

So what is a blow out?

On platform Alpha, where pipe was being extracted from a 3,500 foot deep well the pressure difference created by the extraction of the pipe was not sufficiently compensated for by the pumping of drilling mud back down the well, which caused a disastrous pressure increase. As the pressure built up and started to strain the casing on the upper part of the well, an emergency attempt was made to cap it, but this action only succeeded in further increasing the pressure inside the well. The consequence was that under extreme pressure a burst of natural gas blew out all of the drilling mud, split the casing and caused cracks to form in the seafloor surrounding the well. A simple solution to the problem was now impossible, due to the immense pressure involved, and the large volume of oil and natural gas being released.  This uncontrolled release of oil and gas is called a blow out. 

A good way to visualize a blow out is to think of the old films of oil wells when the drillers first struck oil, the rig shakes and rumbles, and then oil comes shooting out of the ground, up through the derrick and into the sky.  Spindle top (1901) in Texas is a great example of this.  In the old days, there were no blow out preventers (BOP’s), and oil was simply allowed to gather in containment ponds before being scooped into barrels for shipment.  No one gave a second thought to the damage they were doing to the environment.

Today, wells have highly sophisticated BOP’s, including the BP well and our wells here in the Santa Barbara Channel.  So how could a blow out occur if there was a blow out preventer in place?

The simplified cause of the blowout was labeled an “industrial accident.” Yet how the accident precipitated the events that followed was far from simple. Union Oil (now Unocal) had been granted a waiver by the United States Geological Survey that allowed them to use a shorter casing on the pipe than Federal Standards prescribed.  (The well casing is a reinforcing element of the well that is supposed to prevent blowouts. Even though the well itself was capped, the fragmentation of the wellhead resulted in a blow out anyway.)  Oil and natural gas broiled to the ocean surface around the oil platform for eleven days while increasingly desperate attempts were made to contain and stop the spill. The techniques, equipment and resources necessary to combat an oil spill of this magnitude did not exist at the time.  On the eleventh day, chemical mud was successfully used to seal the cracks in the seafloor. 

The fracture of the seafloor was a key element in this spill.  Basically the rock formation that capped the oil reserve fractured and collapsed, resulting in huge cracks across the seafloor where the oil was able to escape.  The only way to stop the spill was to pump sealant into the well and basically plug all of the cracks in the seafloor.

To make a quick comparison, there was a BOP in place on the BP wellhead.  The problem is (apparently), that the BOP was connected to the floating rig on the surface, and when the explosion occurred, communication with the BOP was lost, so there was no way to tell it to shut-off the well.  The workers that escaped from the burning rig say that they went into the control room to activate the BOP, but it was nonresponsive.  When the rig sank, the communication lines connecting the rig with the BOP were severed.  Because the wellhead is almost a mile beneath the surface, BP doesn’t seem to be able to hack into the BOP and get it to function.  A BOP is basically a big valve that can be closed to stop the flow of oil.  It is positioned right at the wellhead, where the pipe enters the ground.

I am still confused as to how a BOP can be designed to shut a well off, but there is no way to operate it remotely and no way to send a ROV (Remotely Operated Vehicle) to the BOP to connect to it and instruct it to close the well off.  It seems like the engineers would have considered the possibility that the rig could break away from the wellhead, especially since in the case of BP, the Deepwater Horizon was a floating rig, with no other connection to the ocean floor, other than the pipe to the well!

The good news is that today, we know a lot more about drilling offshore, and have advanced technologies that are being applied to the platforms that are operating in the Santa Barbara Channel.  Unlike the BOP on the BP wellhead, the BOP’s on our platforms are conventional BOP’s situated on surface, allowing for easy access for daily visual inspections and checks by experienced, competent company personnel.  Restrictions and regulations are also much more stringent today than what we had in place in 1969.  These regulations require (among other things), a regular function and pressure test, witnessed by independent agency.  Also, our BOP’s feature simple BOP control systems that can close the BOP independently of rig power.  They also have a back up BOP closure system as a failsafe.  There are also multiple remote control panels around well site to close the BOP, if the other systems and failsafes don’t work.

The most important difference between our wells and the BP well is that ours are in about 700 feet of water instead of over 5,000 feet, so if anything at all happens, we can get people down to the wellhead immediately.

So, the question remains; could it happen here again?  Before the BP spill occurred, I would have said no; never.  Today, I realize that, regardless of the technology, as long as people are involved in the process, and profits are at stake, errors and accidents can certainly happen.  I do, however, have confidence that, if something does happen—if there is another spill here, it will be addressed quickly and effectively.  With this said, I have a high degree of confidence that regular inspections, high-quality operating procedures, and attention to every detail are a integral part of the operations of our local platforms, and with the BP spill, I think all oil companies will be hyper-sensitive to following all of the rules for a long time to come.

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