Sixth report : nuclear power and the environment : presented to Parliament by command of Her Majesty, September 1976 / Chairman: Sir Brian Flowers.

  • Great Britain. Royal Commission on Environmental Pollution
Date:
1976
Catalogue details

Licence: Open Government Licence

Credit: Sixth report : nuclear power and the environment : presented to Parliament by command of Her Majesty, September 1976 / Chairman: Sir Brian Flowers. Source: Wellcome Collection.

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    Canada and South Africa; supplies are expected soon from Namibia and perhaps from Australia which has large reserves, as yet undeveloped. The ore is crushed and ground to a powder, and uranium is leached out by chemical solvents. It is concentrated as “‘yellowcake’’, and despatched in steel drums. Uranium when recently extracted is radioactive, but being extremely long-lived is only very slightly so, and the main hazard is its chemical toxicity which is similar to that of lead. 120. Because of the radioactive decay of uranium, the untreated ore also contains its decay daughters (see paragraph 34), which include the inert gas radon—222. This is present in the atmosphere in underground mines, and is inhaled by miners along with dust particles to which its own short-lived and highly active daughters adhere. In consequence the miners suffer an unusually large number of lung cancers. Radon continues to be formed by radioactive decay in the discarded tailings, and is readily released to the atmosphere because the tailings are finely divided. This is a health hazard in uranium-mining com- munities, as it is in parts of the United States southwest where huge piles of tailings have been created. 121. Uranium is also present in seawater (3 parts in 10°) and the 4,000 million tonnes theoretically available dwarf the estimated deposits on land. However, although the basic process for extracting uranium from seawater is known to work and the energy cost (mainly power needed for pumping) is only one sixth that of the energy that can be obtained in a thermal reactor power station using the uranium thereby extracted(”*), much development work is still needed. Only a few areas of the world are suitable for the extraction process, as a continual supply of unprocessed water is needed, preferably warm and free from suspended matter that would clog the filters. Japan and the Bahamas are two favoured sites, but the UK is not one. The cost of uranium obtained from seawater is very uncertain, but it is likely to be several times the current price of the element (about £40 per kg.). On the other hand, the environ- mental impact may well be much less than that from the large-scale opencast mining of poor grade ores. Uranium conversion and fabrication 122. At Springfields, where the yellowcake is received and stored, there are two main processes—the purification and chemical conversion of the uranium, and the manufacture of metal and oxide powder into fuel elements. The first consists of normal chemical processes and gives rise to normal chemical effluents of negligible radioactivity. The main environmental] hazards arise from the need to generate and use fluorine and hydrofluoric acid, both of which are poisonous and extremely corrosive. The same is true of hex, which is a white solid at room temperature and pressure, but a gas above 56°C. 123. We described in paragraph 92 why uranium has to be enriched in uranium—235 in order to enhance its ability to sustain a chain reaction. Since the two isotopes have identical chemical properties, the separation has to be based on their difference in mass—a little over 1 per cent. There are several
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