Transuranic wastes

Transportation Index Transport phenomena Transposons Transputer chips Transuranic waste Transuranium elements... 

Classification of wastes may be according to purpose, distinguishing between defense waste related to military appHcations, and commercial waste related to civiUan appHcations. Classification may also be by the type of waste, ie, mill tailings, high level radioactive waste (HLW), spent fuel, low level radioactive waste (LLW), or transuranic waste (TRU). Alternatively, the radionucHdes and the degree of radioactivity can define the waste. Surveys of nuclear waste management (1,2) and more technical information (3—5) are available. 

Weapons materials from production reactors were accumulated during the Cold War period as a part of the U.S. defense program. Prominent were tritium, ie, hydrogen-3, having a of 12.3 yr, and plutonium-239, 1/2 = 2.4 X lO" yr. The latter constitutes a waste both as a by-product of weapons fabrication in a waste material called transuranic waste (TRU), and as an excess fissionable material if not used for power production in a reactor. 

Transuranic Waste. Transuranic wastes (TRU) contain significant amounts (>3,700 Bq/g (100 nCi/g)) of plutonium. These wastes have accumulated from nuclear weapons production at sites such as Rocky Flats, Colorado. Experimental test of TRU disposal is planned for the Waste Isolation Pilot Plant (WIPP) site near Carlsbad, New Mexico. The geologic medium is rock salt, which has the abiUty to flow under pressure around waste containers, thus sealing them from water. Studies center on the stabiUty of stmctures and effects of small amounts of water within the repository. 

Transuranic wastes are so called because they contain isotopes of elements heavier than uranium, primarily plutonium, americium, and neptunium. Since these isotopes emit alpha particles. 

Removes actinides from acidic aqueous solutions to well below the 10 nanocuries per gram (nCi/g) Nuclear Regulatory Commission (NRC) class A low-level transuranic waste requirements for disposal. 

Place, B.G., Treatment Technology for Transuranic Waste Streams Cementation, Vitrification, and Incineration Testing for the Treatment of Spent Ion Exchange Media, Rep. WHC-EP-0462, Westinghouse Hanford Company, Richland, WA (1992)... 

Healy, J. W., Eyman, L. 0., and Trabalka, J. R., Transuranic Uptake by Aquatic Organisms, (Appendix I) in an Examination of Possible Limits for the Shallow Earth Burial of Transuranic Wastes, Los Alamos Scientific Laboratory, Los Alamos,... 

Low-level transuranic wastes are solid or solidified materials which contain plutonium or other long-hved alpha-particle emitters in known or suspected concentrations higher than 10 nanoCuries per gram and external radiation levels after packaging sufficiently low to allow direct handling. 

Intermediate level transuranic wastes are solids or solidified materials that contain long-lived alpha-particle emitters at concentrations greater... 

Transuranic Waste Transuranic waste (TRU) results from fuel reprocessing and fuel fabrication facilities, the production of nuclear weapons, and the decommissioning of nuclear reactors or fuel cycle facilities. TRU includes clothing,... 

Transuranic waste that contains plutonium, americium, and other elements with atomic numbers higher than uranium... 

Any waste not classified as spent fuel, high-level waste, transuranic waste, or uranium or thorium mill tailings... 

Subclassifications of Fuel-Cycle Wastes. As shown in the third level of the hierarchy in Figure 1.1, transuranic waste and low-level waste are further divided into different subclasses. The subclassification of transuranic waste as contact handled or remotely handled is based on the level of external radiation in contact with a waste package. This subclassification is related to requirements for protection of workers during waste operations, but it is not related to requirements for protection of the public following disposal. 

The classification system for fuel-cycle waste is essentially qualitative. As a result, there is substantial ambiguity about whether some wastes should be classified as high-level waste, transuranic waste, or low-level waste. This ambiguity has led to needless disputes about classification of specific wastes that are largely unrelated to important issues of protecting human health. 

Technical requirements on treatment and disposal of spent fuel, high-level waste, and transuranic waste established under AEA should be largely unaffected by the presence of waste classified as hazardous under RCRA Some of these wastes meet technology-based treatment standards for hazardous chemical waste established by EPA (e.gvitrified high-level waste is an acceptable waste form under RCRA). Alternatively, a finding that disposal of the radioactive component of the waste complies with applicable environmental standards established by EPA under AEA can serve to exempt the disposal facility from prohibitions on disposal of restricted hazardous chemical wastes under RCRA [e.g., disposal of mixed transuranic waste at the Waste Isolation Pilot Plant (WIPP)]. 

Some wastes are defined by exclusion (i.e., by what they are not), not on the basis of their properties or associated risks. Low-level radioactive waste is defined as waste that is not high-level waste, spent fuel, transuranic waste, or uranium or thorium mill tailings. Because the excluded wastes are defined by their source, rather than their properties, the definition of low-level waste is not based on properties of the waste and wastes in this class can vary from essentially innocuous to highly hazardous over long time frames. 

Transuranic waste Waste that contains more than 4 kBq g 1 of alpha-emitting transuranium radionuclides with half-lives greater than 20 y, excluding high-level waste Geologic repository ... 

Waste Isolation Pilot Plant (WIPP) in New Mexico is only disposal facility authorized in law commercial transuranic waste also may be acceptable for near-surface disposal on a case-by-case basis. 

Radioactive wastes that arise from operations of the nuclear fuel cycle are divided into five classes, called spent nuclear fuel, high-level waste, transuranic waste, low-level waste, and uranium or thorium mill tailings. At the present time, NARM wastes are not formally divided into different classes (see Section 4.1.2.4). The division of all radioactive waste into fuel-cycle and NARM waste and the division of fuel-cycle waste into five classes constitutes the basic classification system for radioactive waste in the United States. 

According to strict interpretation of transuranic, these wastes could be so classified only if they contained sufficient amounts of elements having an atomic number greater than 92. Despite this, wastes that contained sufficient amounts of 233U and other alpha-emitting non-transuranium radionuclides often were classified and managed as transuranic waste because their specific activities (activities per unit mass) are more similar to those of the transuranium elements than to natural uranium or thorium. 

Transuranic waste. As described in Section 4.1.2.2.2, transuranic waste originally was defined by AEC as solid waste that contains long-lived, alpha-emitting transuranium radionuclides or 233U in concentrations greater than 0.4 kBq g A Transuranic waste so defined was not generally acceptable for shallow-land burial. 

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