Nuclear waste airborne

The advent of a portable source of very high energy x-rays has opened up x-ray inspection possibilities in a wide range of environments. Applications include such fields as nuclear waste containers, bridges, nuclear and fossil power plants, surface and airborne transportation systems, space launch systems and other thick section NDT and other inspection problems that cannot be solved imaged using other NDT methods. 

EPA has issued a variety of regulations that limit the release of radionuclides, including 1-129 and 1-131, to the environment. These regulations address airborne and liquid releases from nuclear reactors, airborne emissions from a variety of industrial and governmental facilities, and allowable radioactive releases from radioactive waste disposal systems. 

Half-lives span a very wide range (Table 17.5). Consider strontium-90, for which the half-life is 28 a. This nuclide is present in nuclear fallout, the fine dust that settles from clouds of airborne particles after the explosion of a nuclear bomb, and may also be present in the accidental release of radioactive materials into the air. Because it is chemically very similar to calcium, strontium may accompany that element through the environment and become incorporated into bones once there, it continues to emit radiation for many years. About 10 half-lives (for strontium-90, 280 a) must pass before the activity of a sample has fallen to 1/1000 of its initial value. Iodine-131, which was released in the accidental fire at the Chernobyl nuclear power plant, has a half-life of only 8.05 d, but it accumulates in the thyroid gland. Several cases of thyroid cancer have been linked to iodine-131 exposure from the accident. Plutonium-239 has a half-life of 24 ka (24000 years). Consequently, very long term storage facilities are required for plutonium waste, and land contaminated with plutonium cannot be inhabited again for thousands of years without expensive remediation efforts. 

Workers at plutonium reprocessing facilities, nuclear reactors, transuranium and low level waste storage facilities, or those engaged in the production or processing of243Am or241 Am may be occupationally exposed to americium. In addition, workers at sites where nuclear testing was conducted may also be exposed to americium. Workers in nuclear power stations may be exposed to airborne radionuclides. The... 

Radioactive waste management involves the treatment, storage, and disposal of liquid, airborne, and solid effluents from the nuclear industry s operations, along with those from other activities that employ the radioactive products. Its strategy involves four approaches limit generation, delay and decay, concentrate and contain, and dilute and disperse. Combinations of all four of these usually are employed to manage each waste stream.39... 

The solid wastes from nuclear operations include the concentrates from liquid and airborne treatment along with paper, clothing, lab glassware, and scrap equipment. The transuranic and low-level wastes both receive... 

Anywhere spent nuclear liiel is handled, there is a chance that iodine-129 and iodine-131 will escape into the environment. Nuclear fuel reprocessing plants dissolve the spent fuel rods in strong acids to recover plutonium and other valuable materials. In the process, they also release iodine-129 and -131 into the airborne, liquid, and solid waste processing systems. In the U.S., spent nuclear fuel is no longer reprocessed, becau.se of concerns about nuclear weapons proliferation. 

Mellinger, P.J. 1985. Health risk assessment for fuel reprocessing plant. Proceedings of the 18th DOE Nuclear Airborne Waste Management and Air Cleaning Conference, Baltimore, MD, August 12-16, 1984, pp. 1019-1025 (ed. WW Pirst). 

Brown, R.A., Christian, J.D. and Thomas, T.R. (1983a). Airborne Radioactive Waste Management, Report No. ENICO-1132 (Exxon Nuclear Idaho Company, Idaho Falls, Idaho). 

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