Uranium tailings disposal

Bearman PJ. 1979. A review of the environmental problems associated with the disposal of uranium tailings. Miner Environ 1 64-74. 

Goode DJ, Wilder RJ. 1987. Ground-water contamination near a uranium tailings disposal site in Colorado. Ground Water 27 545-554. 

ROBERTSON, A.M., et al., Canadian Uranium Mill Waste Disposal Technology, report prepared for the Canadian National Uranium Tailings Programme. Energy, Mines and Resources, Ottawa, Canada (1987). 

Uranium is considered an important material for nuclear energy production. The pumping of uranium slurries is more complicated than pumping most slurries due to its radioactivity. As a result, uranium tailings disposal systems should involve a health specialist and an environmental engineer. 

Dodson, M. E., Opitz, B. E. Sherwood, D. R. 1985. Two-reagent neutralization scheme for controlling the migration of contaminants from a uranium mill tailings disposal pond, PNL-SA-12629 CONF-850242,Managementof uranium mill tailings, low-level waste and hazardous waste. Proceedings of the Seventh Symposium, Fort Collins, CO, 6-8 February 1985, 401-410. 

Spangler, R. Morrison, S. J. 1991. Laboratory-scale tests of a chemical barrier for use at uranium mill tailings disposal sites, CONF-910981. In Wood, D. E. (ed) Proceedings Environmental Remediation 91 Cleaning Up the Environment for the 21st Century, Pasco, WA, 8-11 September, 739-744. 

Fig. 1. Schematic flowsheet of uranium processing (acid leach and ion exchange) operation. Numbers refer to the numbers that appear in the boxes on the flowsheet. Operations (3), (6), (9), and (11) may be done by thickening or filtration. Most often, thickeners are used, followed by filters. The pH of the leach slurry <4) is elevated to reduce its corrosive effect and to improve the ion-exchange operation on the uranium liquor subsequently separated, In tile ion exchange operation (7), resin contained in closed columns is alternately loaded with uranium and then eluted. The resin adsorbs the complex anions, such as UC fSO 4-. in which the uranium is present in the leach solution. Ammonium nitrate is nsed for elution, obtained by recycling the uranium filtrate liquor after pH adjustment. Iron adsoibed with the uranium is eluted with it. Iron separation operation (8) is needed inasmuch as the iron hydroxide slurry is heavily contaminated with calcium sulfate and coprecipitated uranium salts. Therefore, the slurry is recycled to the watering stage (3). Washed solids from 1,6). the waste barren liquor from (7), and the uranium filtrate from (11) are combined. The pH is elevated to 7.5 by adding lime slurry before the mixture is pumped to the tailings disposal area. (Rio Algom Mines Limited, Toronto)...

Thomson, B.M., Longmire, P.A. and Brookins, D.G. (1986) Geochemical constraints on underground disposal of uranium mill tailings. Applied Geochemistry, 1, 335-343. 

Land releases of radium are related to atmospheric fallout of coal fly ash (see Section 5.2.1). For example, elevated radium-226 concentrations in snow have been detected near a coal-fired power plant in Poland (Jaworowski et al. 1971). Other land releases may include the disposal of coal fly ash, lime slurry derived from water softening processes, and uranium mine tailings and associated wind-blown dusts. However, no information was located on the total amount of land-released radium... 

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. 

Low-level waste Any waste not classified as spent fuel, high-level waste, transuranic waste, or uranium or thorium mill tailings Near-surface disposal system or, for high-activity, longer-lived waste, geologic repositoryf... 

Mill tailings Residues from chemical processing of ores for their source material (i.e., uranium or thorium) content Near-surface disposal in situ or at processing site 8 small volumes may be managed as low-level waste... 

Management and disposal of most uranium or thorium mill tailings are governed by the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA, 1978). This Act is concerned with the control and stabilization of mill tailings for protection of public health and the environment. It addresses (1) remedial actions at inactive uranium or thorium processing sites or on properties in the vicinity of... 

Utah, which has a radioactive waste disposal license and a RCRA permit from the state, accepts large volumes of mixed waste containing low concentrations of radionuclides that resembles uranium or thorium mill tailings. 

The previous section mainly considered the considerable impacts of dual regulation of mixed waste on management and disposal of mixed low-level waste. High-level waste, transuranic waste, and uranium or thorium mill tailings also may be subject to dual regulation under AEA (1954) and RCRA (1976). This Section briefly considers the impacts of dual regulation on these wastes. 

Most uranium or thorium mill tailings presumably could be classified as low-hazard waste, but only under conditions of perpetual institutional control over near-surface disposal sites. In the absence... 

Perpetual institutional control over near-surface disposal sites also is envisioned for uranium mill tailings, on account of the unacceptably high risks that could result if tailings piles were released from control and the view that disposal of the very large volumes of these wastes in underground facilities is not feasible (EPA, 1982 ... 

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