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The sea as deep geological repository: a ticking time bomb - Referat

The sea as deep geological repository: a ticking time bomb

The sea as a source and sphere of life is threatened. Until 1982 several states including Germany made use of the northeast atlantic as deep geological repository to store nuclear waste. Overall 114.726 tonnes of nuclear waste in 222.732 barrels were thrown into the sea1.
As a natural process barrels begin to rust. Rust is formed when iron compounds corrode in the presence of water or oxygen. Due to higher concentration of sodium chloride ions in the water, the rusting process tends to happen quicker in the sea. This can become a huge problem in case that barrels being leaky and radioactive substances escape into water and from there in long term mix with the air. The responsible gonverments thought that nuclear waste would not present any danger in 5000 m depth. They assumed that in case substances should escape, water would dilute the substances. Today the dilution of nuclear waste is forbidden because the dilution leads to an uncontrolled distribution of the substances and not as the government thought: the dilution of substances. Since 1995 storation of nuclear waste in oceans is prohibitted. A couple of years later biologists found out that isotope escaped in 5000 m depths through the foodchain may end up in fishing areas.
Fish, plankton, shells and algae take those dangerous substances by breathing or through the foodchain in. What exactly happens then? Iodine swaps in the thyroid gland and cesium in bones and other organs. This leads to bad genetic constitutions, therefore to genetic defects, and also to impotence. Especially threatened sea dwellers could go extinct. At the same time other species could be threatened as a result of the interrupted and poisoned foodchain. Some species even become about 15-25 years old, amongst others, edible fishes. Therefore edible fish may present a long-term risk when they consume poisoned food for a long period of time.

How do radioactive substances spread?
Different isotopes spread differently: substances as cesium-137 and strontium-90 dissolve easily in water. Different than plutonium or americicum, cesium-137 and strontium-90 distribute with the streams and also dilute. Because Plutonium and americicum baste to suspended matters, they sink to the sediment. In some water samplers a high concentration of plutonium 238 could be detected. The radiation of a few millionths of gram of plutonium in human
body is deadly. The half-life period of plutonium is about 88 years, so we can conclude that the contamination of the ocean will be a long-term problem.

Some people now might think: Well, I don't like fish, I don't eat fish, I am not facing any risk. But they're wrong: half of the worldwide fish catch is used to feed farm animals. And again the meat of farm animals is used for our consumption. Vegetarians would be on the safe side, but everyone becoming vegetarian can't be the solution. I have to say that I am quite horrified by the actions the governments took without knowing the true effects nuclear waste stored in the northeast atlantic ocean could have. They're responsible for a whole nation but at the same time act irresponsibly. Nowadays it's not possible to do anything against the rusting barrels, but parts where nuclear waste was thrown in should be regurlarly controlled as well as fishing areas to prevent the worst from happening. Today there's still no solution for storing nuclear waste, currently nuclear waste is placed in temporary stores. I think it's important to find a way to store nuclear waste soon, otherwise we delegate the responsibility to our next generations which wouldn't be fair.

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