Old wrecks & oil Slicks.

[Richard Mason]

Interesting article in the local rag today; not sure if it should be here or in the wrecks forum:

Pacific cloaks a toxic time bomb | The Australian

Certainly some major environmental and huge financial and legal implications, in as much as the countries most affected, such as the Solomons, Micronesia, PNG etc don't have lots of money to chuck at lawyers and salvage contractors.

I understand that even the yanks are baulking at dealing with the oil still sitting in the USS Arizona on the bottom of Pearl Harbor, in maybe 20~30M, so I really don't know how these tiny Pacific nations will handle it. And whilst many are in shallow water and simpler to salvage, there are going to be many which are a long long way down and out of reach, gradually leaking oil at increasingly higher rates as the wartime wrecks age & deteriorate. I guess the only positive in the exercise they are talking about is that while the 19,000,000 litres in the Mississinewa is going to cost $6,000,000 to remove, perhaps it is capable of being re-refined so there may be some cost recovery or offset options available.

Also makes you wonder about the potential hazard in European/Atlantic waters too, given the massive number of circa 1914-18 and 1939-45 wrecks there.

I've not dived many wartime wrecks but for those of you that do, do you ever see evidence of oil leaks?

[Kalahari Diver]

Interesting post! The information that I have been able to find out seems to say that in the long term the Valdez has not been such a disaster as first thought, with microbes eating the oil and improving recovery because of increase in the bottom of the food chain. This does not mean that I am advocating oil leaks everywhere, but I suppose that the ones which leak very slowly are probably less of a problem because nature will recycle the hydrocarbons. I think that the problems of getting oil safely out of the very deep wrecks is a huge [insurmountable] problem but the shallow stuff is probably worthwhile.

I understand that the "Royal Oak" in Scapa dribbles oil, and I am sure someone here will be along with information on quantities and effects.

David.

[CotoChris]

My area was deeply affected by the Prestige oil spill a few years ago. It is really horrific in seeing the crude oil over the beaches and rocks, let alone the birds and sea life. I do wonder what the effect is on the sea chain though after the oil had been cleared.

Interestingly though as a diver my experience was quite different. With the oil spill the government banned fishing, the changes weeks and months later were quite something. Much more fish life in size and quantity, saw octopus at sizes I've never witnessed. This was due to fishing ban. N ot I'm against fishing but believe it should be far better control, not that the Spanish obey anyway!

Last year though in Vigo bay there was mass deaths of Scallops, apparently duye to some toxin. Havn't seen them this year yet.

[NeilP]

There is one wreck close to where I live that was carrying a load of WW1 anti personnel shells bound for the trenches in France when it went down.

When you start digging on it for timing heads or shell cases, then when you get back on the boat I always find that there is a very thin, oily residue on my drysuit and can feel it on my hands.

A friend of mine always has a headache when he gets back after digging on this wreck too.

Maybe some kind of oil or something, not sure really.

[Kalahari Diver]

The headache is probably caused by absorbing explosive through your skin. The women who worked in munitions in the first WW were called canaries because of the colour of their skin from absorbing the explosive, [various forms of nitrocellulose I think] and apparently lived with headaches. By the way is digging around this wise? Anti-personnel was sometimes a euphemism for gas shells and they are so dangerous even now that the Belgian army bomb squads who have lots of experience with this stuff treat them very carefully indeed.

David.

[NeilP]

Originally Posted by Kalahari Diver

The headache is probably caused by absorbing explosive through your skin. The women who worked in munitions in the first WW were called canaries because of the colour of their skin from absorbing the explosive, [various forms of nitrocellulose I think] and apparently lived with headaches. By the way is digging around this wise? Anti-personnel was sometimes a euphemism for gas shells and they are so dangerous even now that the Belgian army bomb squads who have lots of experience with this stuff treat them very carefully indeed.

David.

Yeah, they're ok. Just brass full of cordite.

[witchieblackcat]

I've often wondered what with the ever spiralling cost of oil whether collecting the oil on shipwrecks will ever become commercially viable if it was sold.

Or is the oil too polluted to be of any use?

[Adrian Kelland]

Originally Posted by witchieblackcat

I've often wondered what with the ever spiralling cost of oil whether collecting the oil on shipwrecks will ever become commercially viable if it was sold.

Or is the oil too polluted to be of any use?

Relatively small amounts though.

[Last Man Standing]

A slow release of oil seems to have far less of an impact than the sudden release of large quantities. Its when large quantities are suddenly released in shallow, coastal waters that there seems to be a real problem.
Millions of tonnes of oil leaks into the sea naturally from leaking reserves far below the surface. Its a naturally ocurring source of pollution but one the oceans have survived with for thousands of years.
I guess with many of these wrecks, the risk of pollution that will go with any attempt to remove the oil may outweigh the risk of leaving it where it is and hoping it will gradually leak away over a long period of time?

[Richard Mason]

Originally Posted by Last Man Standing

A slow release of oil seems to have far less of an impact than the sudden release of large quantities. Its when large quantities are suddenly released in shallow, coastal waters that there seems to be a real problem.
Millions of tonnes of oil leaks into the sea naturally from leaking reserves far below the surface. Its a naturally ocurring source of pollution but one the oceans have survived with for thousands of years.
I guess with many of these wrecks, the risk of pollution that will go with any attempt to remove the oil may outweigh the risk of leaving it where it is and hoping it will gradually leak away over a long period of time?

Good point, slicks in deep ocean areas way out in the wupwup are probably less of an issue, especially in view, as you say, of natural seeps anyway.

It's places like Guadalcanal, Yap, Truk, PNG etc, where they are in shallow, close to shore and in sensitive habitats that's probably the biggest concern. Locations in the tropics are often much quyieter waters too, compared with the North Atlantic or Southern Ocean, whererough water and strong winds often break up slicks, like that one off Shetland a few years back, mid winter, howling storm and most of it dispersed.