Tailings from uranium mills radioactivity

TAILINGS. In the nuclear context, the depleted stream remaining from a uranium enrichment process or from uranium milling. In relative terms, the tailings (also occasionally referred to as tails ) are depleted uranium reduced in uranium-235, while the enrichment process is enriched in that Isotope. In general, tailings make poor sources for development of nuclear weapons or for use in radlolt ical dispersal devices (RDD) because they are low in radioactive uranium-235. 

Table 5.24 Aiibome radioactive effluents from modd uranium mill and 20 years tailings storage ...

Thus, LLRW is defined more by what it is not than by what it is, that is, LLRW is defined by exclusion. LLRW is radioactive waste that is not HLRW, TRU waste, SNF, or byproduct material (commonly referred to as uranium mill tailings). All of these have separate legal definitions. Naturally occurring radioactive material and technologically enhanced NORM are also defined separately from LLRW but are not currently regulated under federal statute. 

The similarities are of the following kinds. First, neither classification system includes a general class of exempt waste. Second, neither classification system is comprehensive, because the classification system for radioactive waste distinguishes between fuel-cycle and NARM waste and the classification system for hazardous chemical waste excludes many potentially important wastes that contain hazardous chemicals. Third, any waste must be managed and disposed of in a manner that is expected to protect public health and the environment. In addition, the approach to disposal of hazardous chemical waste under RCRA, which emphasizes monitoring of releases from disposal facilities and an intention to maintain institutional control over disposal sites for as long as the waste remains hazardous, is applied to disposal of uranium or thorium mill tailings under AEA. 

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. 

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. 

Low-level waste is any radioactive waste that arises from operations of the nuclear fuel cycle except for spent fuel, high-level waste, transuranic waste, and uranium or thorium mill tailings. 

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