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181.
Direct measurement of the accumulation of non-radioactive traceelements in aquatic biota near uranium mining or processing sites has been relatively rare, with greater focus on the radiological activity in the adjacent soils and groundwater. To evaluate the potential ecological concern associated with trace elements at a former uranium mill site in southeasternUtah, benthic macroinvertebrates were collected and analyzed for 17 trace elements from multiple locations within a small on-site stream, Montezuma Creek, and a nearby reference stream. Key questions of this study relate to the spatial and temporalextent of contamination in aquatic biota, the potential ecological risks associated with that contamination, and the usefulness of benthic macroinvertebrates as a monitoring tool at this site. Composite samples of similar macroinvertebrate taxa and functional feeding groups were collected from each site over atwo year period that was representative of normal and dry-yearconditions. In both years, mean concentrations of arsenic,molybdenum, selenium, and vanadium were significantly higher (afactor of 2–4 times; P < 0.05) in macroinvertebrates collectedfrom one or both of the two Montezuma Creek sites immediatelydownstream of the mill tailing site in comparison toconcentrations from reference locations. Mean uraniumconcentrations in invertebrates immediately downstream of themill site were more than 10 times higher than at reference sites.The site-to-site pattern of contamination in Montezuma Creekinvertebrates was similar in 1995 and 1996, with mill-relatedtrace elements showing a downstream decreasing trend. However,nine of seventeen contaminant concentrations were higher in thesecond year of the study, possibly due to a higher influx of deepgroundwater during the drier second year of the study. Apreliminary assessment of ecological risks, based on the benthicmacroinvertebrate bioaccumulation data, suggests that aquatic andterrestrial population risks are low. Benthic macroinvertebratesappeared to be sensitive integrators of trace element inputs tothe aquatic environment from a former uranium mill tailing site,and provided useful spatial and temporal patterns ofcontamination not easily obtained using conventional surfacewater or groundwater measures.  相似文献   
182.
The Kyrghyz Republic, located in the southeastern region ofthe former Soviet Union, maintains a population of more thanone-half-million persons and is heavily dependent on LakeIssyk-Kyol, both to draw tourists to the area and for itsutilization by some as a food and recreation source. Historical surveys, conducted primarily for geologicalexploration, have indicated that localized areas ofshoreline on Lake Issyk-Kyol have relative radiation levelsin excess of ambient background by as much as a factor often. Uranium mining operations in the mountains borderingthe lake to the south may have resulted in the contaminationof a number of areas on the lake's southern shore. Concentrations of naturally occurring uranium, thorium, andpotassium are present in these soils in elevated quantities. This paper presents the results of an investigation of soilconcentrations along the shoreline of Lake Issyk-Kyolrelative to previously discovered areas of high exposurerate.  相似文献   
183.
铀矿通风与降氡技术研究   总被引:1,自引:0,他引:1  
铀矿通风中,风量、风压和风流方向是三个影响降氡技术的重要因素.为了把铀矿井平均氡浓度降到一个合理的可接受水平,必须对这三个因素综合考虑,使铀矿井处于最佳工作状态和最优的辐射水平.  相似文献   
184.
铀矿山安全事故分析与对策   总被引:2,自引:0,他引:2  
对铀矿山伤亡事故在不同的环境因素中发生的次数进行了比较,发现特定环境因素对伤亡事故的发生有密切的影响,提出了预防伤亡事故的相应对策。  相似文献   
185.
ABSTRACT: To help meet national energy demands, interest has been focused on the coal, oil shale, and uranium deposits of the Upper Colorado River Basin. Several energy output projections for the basin have been presented based upon water availability. Inherent in all these analyses are estimates as to the rate of water use in each energy development. New energy technologies are characterized by parameters extrapolated from small scale energy facilities. The data provide projected costs, conversion efficiencies, and material inputs and outputs. Alternative techniques for process cooling and solids handling provide variable rates of water use which affect other conversion parameters. Results from a mathematical model are used in analyzing the sensitivity of an optimal energy development strategy for the Upper Colorado River Basin. The impacts of alternative water use rates are investigated in terms of net energy output, total cost, and displacements in the development strategy. Similarly, controls and regulations on energy resource development are evaluated.  相似文献   
186.
Calculations regarding the long-term hazards to health from the radioactive gas radon which emanates from the tailings of milled uranium ores are presented here. The absolute and relative risks to the population from mill tailings, as well as technical solutions to the problem of disposal methods which would eliminate or minimize lung cancer risk, are discussed. Since the emission of radon from tailings will occur thousands of years after the projected benefits from nuclear-fission power have been obtained, the problem of present and future hazard from mill tailings calls for increased regulatory consideration.Now at Resources for the Future, Washington, D.C. 20036  相似文献   
187.
地浸采铀中的环境污染与保护   总被引:5,自引:0,他引:5  
随着采矿工艺技术发展,地浸采铀逐渐取代了传统的山地工程采矿,其基本原理是对可地浸砂岩型铀矿按一定网度布置工艺钻孔,从注液孔注入地浸液,使之与铀进行充分反应,经抽液孔提出地表,在地表工厂进行萃取铀的过程。地浸采铀与传统的山地工程比,地表破坏小、形成的放射性废物和放射性核素的污染少、环境复原成本低,但也会对大气、土壤、地表水,特别是对地下水造成一定的污染.必须采取一定的防护措施,否则会对环境及人们身体健康造成巨大的危害。  相似文献   
188.
江西火山岩型铀矿成矿特征及找矿前景   总被引:4,自引:1,他引:4  
江西省居华南铀成矿区(省)的中心地带。省区内地层发育齐全,岩浆活动频繁,地质构造复杂,成矿条件优越,矿产资源丰富。火山岩型铀矿是我国四大铀矿工业类型之一,江西火山岩型铀矿在我国已探明的铀矿资源量中占相当重要的地位。本文在分析江西地质构造背景和江西铀矿分布特征的基础上,详细阐述了江西火山岩型铀矿成矿规律,分析了江西火山岩型铀矿的找矿前景,为华东火山岩型富大铀矿的寻找提供依据。  相似文献   
189.
Application of magnetic U(VI) ion imprinted polymers (IIPs) coated on magnetic nanoparticles was investigated for pre-concentration and determination of U(VI) ions in aqueous solutions. The scanning electron micrographs revealed the microporosity of the adsorbent. Uranium leaching was successful as the energy-dispersive X-ray spectra showed. The Brunauer–Emmett–Teller (BET) surface area improved by more than 13-fold (83.1 and 6.2 m2 g?1 for the leached and unleached magnetic IIP, respectively). U(VI) uptake was optimized using batch experiments with parameters affecting the uptake performance, such as initial uranium concentration, pH, contact time, and adsorbent dose investigated. Pseudo-second-order kinetics and the Langmuir isotherm model best fitted the experimental data. The maximum adsorption capacity of uranium onto the activated magnetic IIP reached 5.4 mg g?1. The selectivity order was determined to be U(VI) > Ni(II) > Th(IV).  相似文献   
190.
电感耦合等离子体质谱法测定饮料中的铀   总被引:2,自引:0,他引:2  
建立了电感耦合等离子体质谱法(ICP-MS)测定饮料中的铀.对不同基质的饮料进行了前处理方法的摸索,从精密度和回收率考察了方法的准确性,相对标准偏差(RSD)为1.67%-8.21%(n=6),加标回收率为96.0%-109.0%,方法检出限为0.010μg·l~(-1),方法准确可靠.  相似文献   
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