Radioactively contaminated debris

External radioactive contamination occurs when a radioactive isotope (e.g. debris from a nuclear explosion) is deposited on the skin and clothing. Such debris is usually in the form of a dust. This contamination can be removed by surface cleaning with soap and water (as for chemical contamination). Care must be taken during external decontamination to avoid accidental ingestion and subsequent internal contamination. 

Denmark 1.5 days after the explosion. Air samples collected at Roskilde, Denmark on April 27-28, contained a mean air concentration of 241Am of 5.2 pBq/m3 (0.14 fCi/m3). In May 1986, the mean concentration was 11 pBq/m3 (0.30 fCi/m3) (Aarkrog 1988). Whereas debris from nuclear weapons testing is injected into the stratosphere, debris from Chernobyl was injected into the troposphere. As the mean residence time in the troposphere is 20-40 days, it would appear that the fallout would have decreased to very low levels by the end of 1986. However, from the levels of other radioactive elements, this was not the case. Sequential extraction studies were performed on aerosols collected in Lithuania after dust storms in September 1992 carried radioactive aerosols to the region from contaminated areas of the Ukraine and Belarus. The fraction distribution of241 Am in the aerosol samples was approximately (fraction, percent) organically-bound, 18% oxide-bound, 10% acid-soluble, 36% and residual, 32% (Lujaniene et al. 1999). Very little americium was found in the more readily extractable exchangeable and water soluble and specifically adsorbed fractions. 

But for chemists, the hydrogen bomb tests had a happier fallout too. Scientists at the Mike test collected coral from a nearby atoll contaminated with radioactive debris, and sent it to Berkeley for analysis. There the nuclear chemists found two new elements, with atomic numbers 99 and 100. They were named after two of the century s most creative physicists einsteinium and fermium. 

The radiological impact of the Chernobyl debris compared with that from nuclear weapons fallout. Journal of Environmental Radioactivity, 6,151-62. Aarkrog, A. Lippert, J. (1971) Direct contamination of barley with 51 Cr,59Fe,58 Co, 65Zn, 203Hg and 210Pb. Radiation Botany, 11, 463-72. 

Leaching of contaminants Eission products Tc, partitioned from high-level waste tanks, debris from contaminated pipes from K-25 plant at Oak Ridge Cs, from salt supernatant and sludge, silico-titanates, and wastewater Radioactive components Ra, Fernald silo waste, transuranics, simulated and actual Rocky Flats ash waste, wastewater... 

Liquid metal walls in ICF reactors will become contaminated with target debris. In addition to posing compatibility problems, these contaminants affect pumping power, pump life, and radioactive inventory. Thus, methods of removing contaminants, particularly high-Z elements, from liquid lithium are required. For example, no economical method to remove Pb to below 1 a/o (23 w/o) in Li has been devised. 

Incineration processes can be used to treat the following waste streams explosives-contaminated soil and debris, explosives with other organics or metals, initiating explosives, bulk explosives, unexploded ordnance, bulky radioactive waste, and pyrophoric waste. In addition, incineration can be applied to sites with a mixture of media, such as concrete, sand, clay, water, and sludge, provided the media can be fed to the incinerator and heated for a sufficient period of time. 

However, marine food is not, and probably never will be, contaminated at a level that represents any danger to consumers. The ocean has always received debris from human activities and has a potential for receiving much more and thereby help to solve the waste disposal problems of humans. But as soon as a waste product is released and diluted in the sea it is almost impossible to retrieve. Therefore, in principal, no waste should be disposed of in the sea without clear documentation that it will never create any damage to the marine environment and its living resources. This means that with present knowledge no radioactive wastes should be allowed to be released into the sea. 

Solid radioactive waste results from the operation and maintenance of the nuclear power plant and its associated processing systems for gaseous and liquid radioactive waste. The nature of such waste varies considerably from plant to plant, as do the associated levels of activity. Sohd radioactive waste may consist of spent ion exchange resins (both bead and powder) cartridge filters and pre-coat filter cake particulate filters from ventilation systems charcoal beds tools contaminated metal scrap core components debris from fuel assemblies or in-reactor components and contaminated rags, clothing, paper and plastic. 

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