Much of oil spill has naturally dispersed or evaporated

[Ought Six]

http://www.nytimes.com/2010/07/28/us...pagewanted=all


ABC News reports that cleanup crews cannot find any oil to clean up:

http://abcnews.go.com/WN/bp-oil-spil...ry?id=11254252

So much for the hysterical predictions of the ultimate ecological disaster of all time.

[Suz]

Funny that they can still find oil chunks from the Exxon Valdez after all these years, but the oil from the gulf has dispersed/evaporated.

(My understanding of oil is that since it's composed of various large, complicated molecules it evaporates very, very slowly.)

[Ought Six]

Not all oil is created equal. The stuff in the Gulf is light, sweet crude, which has a much higher percentage of volatile stuff that evaporates. Also, the Gulf has very warm water, which means more bacterial to break down the oil. The warmer water also means lower viscosity and easier dispersal. And the leak is far out to sea and a mile below the surface, allowing much of the oil to disperse before it reaches shore.

Conversely, the Exxon Valdez oil was heavy crude dumped right on top of the water a very short distance from shore. The very cold temps mean that very little bacterial degradation occurred. The oil was heavy crude, and the cold kept the viscosity even higher.

In other words, the two spills were radically different situations. Not surprisingly, they had very different results.

[Auburn Boy]

Originally Posted by Suz

Funny that they can still find oil chunks from the Exxon Valdez after all these years, but the oil from the gulf has dispersed/evaporated.

(My understanding of oil is that since it's composed of various large, complicated molecules it evaporates very, very slowly.)

Different grade of oil, colder environment, less hospitable to the kind of micro-organisms that eat oil, and more rocky shoreline which allowed the oild to penetrate deeper under the surface and thus avoid oxidation and cleanup.

[CanadaSue]

Maybe if they checked for the tiny little droplets of it up & down the water column...?

[dyrt]

The volatile components of oil evaporate within a dozen hours or so if laying on the surface in the sun. The reason that there is very little oil to see is the huge amounts of dispersal chemicals that were injected into the leaked oil at the wellhead.

It will be interesting to see the long term effects of breaking up the oil so it is dispersed and mixed with water at depths instead of letting it all set on the surface. The gulf has a lot of little creatures that feed on oil. At the least I would expect a population explosion of those creatures.

Other than that, nobody knows but the media will always prefer the doomer stories.

[jason]

Yes. It's all gone! It has nothing to do with the million gallons of dispersants that sink it.

[Exodia]

Originally Posted by jason

Yes. It's all gone! It has nothing to do with the million gallons of dispersants that sink it.

Dispersants don't sink things, they disperse them into much smaller particles which leads to greater surface area of the particles. My thought is that this would make it easier for the naturally occurring processes to do their jobs.

Now I'm going to piggy back on dyrt's thought, and suggest an outrageous idea. I too would expect to see a spike in the microbes that feed on oil. Something must feed on them. Also, there has been a major slowdown on commercial fishing in the area. I would not be shocked to see bumper years of fishing a few years after the all clear is sounded.

[CanadaSue]

I've been watching various: "Where's the oil?" clips on different news outlets. Most are using this odd light - almost looks like blacklight; maybe it is. Plenty of oil showing up in the sand - on some beaches, when you dig down, you can see one or more layers of it. Other films sadly, show oil close to & going down into, the dens of various marine life.

It can't simply have all magically evaporated away or broken down into wonderfully non-toxic components.

I very much fear we'll see it - indirectly, in the next many generations of marine life.

It's there. And as pointed out, different spills, different profiles.

[Exodia]

Originally Posted by CanadaSue

It can't simply have all magically evaporated away or broken down into wonderfully non-toxic components.

Sue, it's a naturally occurring substance, and leaks into the Gulf all the time. Before the spill the Gulf was not a toxic cesspool, so there must be natural processes that mitigate it.

[DReynolds]

Mankind has virtually no experience with a large spill under a mile of oceanwater. The Ixtoc spill was in shallow water. The Valdez spill (and all shipping accidents) was on the surface and was also in relatively shallow water. The massive spills in 1991 into the Persian Gulf were in shallow water.

Only time will tell how fast crude oil degrades under these circumstances, having been liberally dosed with Corexit, and having emanated from 1mile below the sea. We just don't know. My guess is there will be virtually no LA oysters next season. We'll see.

[Exodia]

From a Yahoo article today:

Perhaps the most important cause of the oil’s disappearance, some researchers suspect, is that the oil has been devoured by microbes. The lesson from past spills is that the lion’s share of the cleanup work is done by nature in the form of oil-eating bacteria and fungi. The microbes break down the hydrocarbons in oil to use as fuel to grow and reproduce. A bit of oil in the water is like a feeding frenzy, causing microbial populations to grow exponentially.

Typically, there are enough microbes in the ocean to consume half of any oil spilled in a month or two, says Howarth. Such microbes have been found in every ocean of the world sampled, from the Arctic to Antarctica. But there are reasons to think that the process may occur more quickly in the Gulf than in other oceans.

Microbes grow faster in the warmer water of the Gulf than they do in, say, the cool waters off Alaska, where the Exxon Valdez spill occurred. Moreover, the Gulf is hardly pristine. Even before humans started drilling for oil in the Gulf — and spilling lots of it — oil naturally seeped into the water. As a result, the Gulf evolved a rich collection of petroleum-loving microbes, ready to pounce on any new spill. The microbes are clever and tough, observes Samantha Joye, microbial geochemist at the University of Georgia. Joye has shown that oxygen levels in parts of the Gulf contaminated with oil have dropped. Since microbes need oxygen to eat the petroleum, that’s evidence that the microbes are hard at work.

The controversial dispersant used to break up the oil as it gushed from the deep-sea well may have helped the microbes do their work. Microbes can more easily consume small drops of oil than big ones. And there is evidence the microbes like to munch on the dispersant as well.

http://news.yahoo.com/s/ynews_excl/ynews_excl_sc3270

[DReynolds]

Originally Posted by Exodia

And there is evidence the microbes like to munch on the dispersant as well.

Hi! I'm a Red Flag!

(I don't think serious journalism involves implying that the toxic dispersant, Corexit, is good for the environment. The use of the language "like to munch on" makes me wonder if this puff-piece came from one of the BP-employed journalists).

[Exodia]

The article didn't say it was good for the environment, it said that the microbes may feed on it as well (albeit in a 6th grade way of saying it).

If the microbess like hydrocarbons, then any hydrocarbon source will likely serve as food. I'm not sure of the make-up of Corexit, but if it has surfactants/polymers as part of it, many of these are derrived from pretoleum sources and may well serve as a food source.

[DReynolds]

Originally Posted by Exodia

If the microbess like hydrocarbons, then any hydrocarbon source will likely serve as food. I'm not sure of the make-up of Corexit, but if it has surfactants/polymers as part of it, many of these are derrived from pretoleum sources.

The point is that Corexit is toxic to marinelife (meaning plankton, fish and crustaceans), and there is a large literature devoted to debating just how toxic it is. Nobody in their right mind would interpret this literature in terms like "microbes like to munch" on Corexit.

It's like saying "oh, don't worry about pollution in Philadelphia. There's even evidence that microbes like to munch on smog". Advertising. Not science, not facts, not evidence, not truth. Just whatever BS comes into the head of the 23yr old "journalist" who just graduated from Yale.

[Auburn Boy]

Originally Posted by DReynolds

The point is that Corexit is toxic to marinelife (meaning plankton, fish and crustaceans), and there is a large literature devoted to debating just how toxic it is. Nobody in their right mind would interpret this literature in terms like "microbes like to munch" on Corexit.

It's like saying "oh, don't worry about pollution in Philadelphia. There's even evidence that microbes like to munch on smog". Advertising. Not science, not facts, not evidence, not truth. Just whatever BS comes into the head of the 23yr old "journalist" who just graduated from Yale.

Even a million gallons of corexit is like a 24 ounce can of soda dumped into a football stadium full of water..,

The Navy used to have a saying..,

"The solution to pollution is dilution..,"

The corexit (and the oil spill) is being very, very seriously diluted.

Admitedly, immediate visibility shows damage and causes concern, but in the near term the whole thing will dissipate, dilute, disperse, diffuse..,

(Oh, I almost forgot DIGEST, can't go forgetting them munching microbes!)

[DReynolds]

Originally Posted by Auburn Boy

in the near term the whole thing will dissipate, dilute, disperse, diffuse..,

The "whole thing" will dissipate, but nobody knows how quickly. And it's pollyanish to declare that we don't need to worry about nothin because the Ocean's so big.

[Exodia]

Originally Posted by DReynolds

The "whole thing" will dissipate, but nobody knows how quickly. And it's pollyanish to declare that we don't need to worry about nothin because the Ocean's so big.

It's also foolish to discount how big it is because toxicity has everything to do with concentration.

[rc]

I do find it interesting that the focus (not just here, but other places as well) is on the damage caused by the evil dispersants.

Presumably, BP had to pay for the evil dispersants, and then inject them into the ocean merely because it was the evil thing to do, because it would cause greater harm, not because it would mitigate the harm, not even a tiny amount.

I'm no chemist, but I assumed that they were dumping something like Dawn(R) dishwashing liquid, albeit probably the industrial version, and probably in the giant economy-size bottle.

[DReynolds]

Originally Posted by rc

I do find it interesting that the focus (not just here, but other places as well) is on the damage caused by the evil dispersants.

Presumably, BP had to pay for the evil dispersants, and then inject them into the ocean merely because it was the evil thing to do

I find it interesting that some people mock the toxicity of Corexit, and think that if a large corporation like BP used some compound, then it must be safe.

How about this--there is a shitload of scientific evidence that Corexit is toxic. Can we at least agree on that? Or have we all lost our minds?

[rc]

I'm not "mocking the toxicity" of it. I assume that Dawn Dishwashing liquid is toxic, and since this stuff is probably stronger, then it's probably more toxic.

But they presumably paid money for the stuff (unless it was toxic waste from some other process). Since BP is evil and wants to maximize its profits, why would they waste money on the stuff?

[DReynolds]

Originally Posted by rc

Since BP is evil and wants to maximize its profits, why would they waste money on the stuff?

They would spend money on the stuff because it disperses the oil. This makes it look like there is less oil. This makes BP look better. This increases the value of BP incorporated. However, the Corexit itself is toxic poison, and they would prefer to ignore that fact, and so they hire "journalists", and when you read a quote like microbes "like to munch" on Corexit, one suspects that the author is an idiot and/or employee of BP.

[Auburn Boy]

Originally Posted by DReynolds

They would spend money on the stuff because it disperses the oil. This makes it look like there is less oil. This makes BP look better. This increases the value of BP incorporated. However, the Corexit itself is toxic poison, and they would prefer to ignore that fact, and so they hire "journalists", and when you read a quote like microbes "like to munch" on Corexit, one suspects that the author is an idiot and/or employee of BP.

As Exodia, Potemkin, and others have noted, the idea of dispersants is not to "make it LOOK LIKE ther is less oil."

It is to break up the oil slick into very small emulsified droplets that will more rapidly be disposed of by the natural processes we have already mentioned here time and again..,

[DReynolds]

Originally Posted by Auburn Boy

As Exodia, Potemkin, and others have noted, the idea of dispersants is not to "make it LOOK LIKE ther is less oil."

Thanks for explaining that. I thought that a dispersant was like food coloring and just changed the appearance of the oil. You must be real educated.

[Auburn Boy]

Originally Posted by DReynolds

Thanks for explaining that. I thought that a dispersant was like food coloring and just changed the appearance of the oil. You must be real educated.

Don't make bland assumptions, not having a clue as to what my background is, of Dr. Hominem.

I have a degree in chemical engineering, first specializing in petrochemical refining, and later in semiconductor physics and microcircuit fabrication.