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Dr Patricia Ash

The deep water horizon oil well, and that’s located in the depths of the Gulf of Mexico, which is quite a sensitive area, and has been for a long, long time, because it’s an area that’s very rich in sea life.  Fishing is very good, it’s got a huge shrimp fishery, much of the Gulf is enclosed by swamp salt marsh which helped to create a suitable environment for the shrimp larvae, for the fish larvae, so the whole thing is a marine ecosystem based on a coast that is essentially made up of very fine sediments.  So it is a particularly vulnerable area.  The deep water horizon oil well is located deep in the Gulf of Mexico, and I don’t think it was ever envisaged that it would leak any oil, and it was felt that it was safe. 

BP are attempting to collect the oil, they're trying various methods.  They’ve tried putting a dome over.  Intuitively it does sound like a good technique; they're trying to funnel the oil so that they can collect it easily, harvest it and prevent it from escaping.  The oil that is escaping, it is being treated with detergents.  Now although the detergents we’re using now are supposedly less toxic than the ones that we used way back in 1967, nevertheless they are still toxic, it’s not a good idea to have those sloshing around in the sea.  And we need to wait to see what happens because of that, because the immediate problem is the actual oil, which is gushing out at quite a huge rate, and it is reaching the surface, floating there, as one would expect, and we are getting the usual processes, i.e. once it’s floating, the lighter components, such as toluenes, xylenes and benzene are evaporating off, but they are essentially leaving behind the larger molecules, the thicker components, so we are seeing sort of rafts of thicker oil floating. 

But local people in the Gulf, especially shrimp fishermen, are getting together and they're using U-shaped booms to collect some of this, and they reckon they can do sort of 3,000 gallons at a time, and they're setting it on fire.  So you may have seen some pictures in the news recently, and now, where you see sort of plumes of smoke coming up from what looks like a couple of little boats, but when you look closely you see that it’s actually a raft of oil burning.  Where there’s really bad weather you will get mousses, which can be a devil to shift because they can be quite stable.  Eventually, as more and more of the lighter stuff evaporates, if the sea is still, and then the raft of the different oils will become much more viscous and thick and it will start reacting with oxygen and forming sort of more and more dense tar-like substances, which with the actions of the sea can form little balls, and that’s where the tar balls come from that we all know so well unfortunately, and they float and they can be deposited on beaches all over the place.

4’00”

Oil and water

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