toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Ruiz, O.; Thomson, B.; Cerrato, J.M.; Rodriguez-Freire, L. url  openurl
  Title Groundwater restoration following in-situ recovery (ISR) mining of uranium Type Journal Article
  Year 2019 Publication Applied Geochemistry Abbreviated Journal  
  Volume 109 Issue Pages 104418  
  Keywords (up) Aquifer stabilization, Ground water restoration, In-situ leach mining, In-situ recovery, Uranium  
  Abstract From 1950 through the early 1980’s New Mexico accounted for roughly half of domestic uranium (U) production for the nuclear power industry and the nation’s weapon programs. Increased interest in nuclear energy has led to proposals for renewed development using both underground mining and uranium in situ recovery (ISR). When feasible, ISR greatly reduces waste generated by the mining and milling processes, however, the ability to restore ground water to acceptable quality after ISR ends is uncertain. This research investigated two methods of stabilizing an aquifer following ISR. Batch and column studies were performed to evaluate chemical and biological methods of stabilization. Columns packed with ore were first leached with an aerated NaHCO3 ground water solution to simulate ISR. Constituents present at elevated concentrations after leaching included molybdenum (Mo), selenium (Se), U, and vanadium (V). Chemical stabilization was studied by passing a phosphate (PO43-) amended solution through the ore to achieve passivation of mineral surfaces by P precipitates. Microbial stabilization was studied by passing a lactate solution through the ore to stimulate growth of anaerobic metal- and sulfate-reducing organisms to reduce U and other elements to less soluble phases. Analyses of the solids from the columns after completion of these experiments by X-ray photo electron spectroscopy (XPS) identified phosphate on samples near the column inlet of the chemically stabilized columns. Microbial populations were characterized by Illumina DNA sequencing and confirmed the presence of metal- and sulfate-reducing organisms. Neither chemical nor microbial stabilization method achieved contaminant immobilization, which is believed due to limited mixing of the stabilization solutions with the contaminated leach solutions. These results emphasize that ground water hydrodynamics, especially mixing, must be considered in aquifer restoration of soluble constituents.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0883-2927 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ ruiz_groundwater_2019 Serial 153  
Permanent link to this record
 

 
Author Hall, S.M.; Gosen, B.S.V.; Paces, J.B.; Zielinski, R.A.; Breit, G.N. url  openurl
  Title Calcrete uranium deposits in the Southern High Plains, USA Type Journal Article
  Year 2019 Publication Ore Geology Reviews Abbreviated Journal  
  Volume 109 Issue Pages 50-78  
  Keywords (up) Calcrete, Carnotite, Finchite, Geochemistry, Uranium, Vanadium  
  Abstract The Southern High Plains (SHP) is a new and emerging U.S. uranium province. Here, uranyl vanadates form deposits in Pliocene to Pleistocene sandstone, dolomite, and limestone. Fifteen calcrete uranium occurrences are identified; two of these, the Buzzard Draw and Sulfur Springs Draw deposits, have combined in-place resources estimated at about 4 million pounds of U3O8. Ore minerals carnotite and finchite are hosted in dolomite at the Sulfur Springs Draw deposit, with accessory fluorite, celestine, smectite/illite, autunite, and strontium carbonate. Host carbonate at the Sulfur Springs Draw deposit is ∼190 ka and mineralization mobilized as recently as 3.8 ka. Ash collected near the deposit is 631 ka and erupted from the Yellowstone caldera complex. The Triassic Dockum Group that contains sandstone-hosted uranium deposits throughout the region and underlies the SHP is a potential source for uranium and vanadium. Regional uplift and dissection reintroduced oxygenated groundwater into the Dockum Group, mobilizing uranium. Additional uranium may have been contributed to groundwater by weathering of volcanic ash in Pliocene and Pleistocene host rocks. The locations of the uranium occurrences are mostly in modern drainage systems in the southeast portion of the SHP. Modelling of modern groundwater in the SHP carried out in a parallel study shows that a single fluid could form carnotite through evaporation, and that fluids of the requisite composition are more prevalent in the southern portion of the SHP. The southeastern portion of the SHP hosts more uranium occurrences due to a variety of factors including (1) upward transport of groundwater and connectivity between source and host rock, (2) higher uranium and vanadium content of groundwater, (3) higher rates of groundwater recharge in this region to drive the mineralizing system, and (4) shallower groundwater facilitating surface evaporation. Ongoing erosion of host rocks challenges preservation of deposits and may limit their size.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0169-1368 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ hall_calcrete_2019 Serial 124  
Permanent link to this record
 

 
Author Rosen, M.R.; Burow, K.R.; Fram, M.S. url  openurl
  Title Anthropogenic and geologic causes of anomalously high uranium concentrations in groundwater used for drinking water supply in the southeastern San Joaquin Valley, CA Type Journal Article
  Year 2019 Publication Journal of Hydrology Abbreviated Journal  
  Volume 577 Issue Pages 124009  
  Keywords (up) California, Central Valley, Geochemistry, Groundwater San Joaquin Valley, Uranium  
  Abstract Concentrations of uranium (U) \textgreater30 µg/L in groundwater are relatively uncommon in drinking water in the United States but can be of concern in those areas where complex interactions of aquifer materials and anthropogenic alterations of the natural flow regime mobilize U. High concentrations (\textgreater30 µg/L) of U in the southeastern San Joaquin Valley, California, USA, have been detected in 24 percent of 257 domestic, irrigation, and public-supply wells sampled across an approximately 110,000 km2 area. In this study we evaluated mechanisms for mobilization of U in the San Joaquin Valley proposed in previous studies, confirming mobilization by HCO3 and refuting mobilization by NO3 and we refined our understanding of the geologic sources of U to the scale of individual alluvial fans. The location of high concentrations depends on the interactions of geological U sources from fluvial fans that originate in the Sierra Nevada to the east and seepage of irrigation water that contains high concentrations of HCO3 that leaches U from the sediments. In addition, interactions with PO4 from fertilized irrigated fields may sequester U in the aquifer. Principal component analysis of the data demonstrates that HCO3 and ions associated with high total dissolved solids in the aquifer and the percentage of agriculture near the well sampled are associated with high U concentrations. Nitrate concentrations do not appear to control release of U to the aquifer. Age dating of the groundwater and generally increasing U concentrations of the past 25 years in resampled wells where irrigation is prevalent suggests that high U concentrations are associated with younger water, indicating that irrigation of fields over the past 100 years has significantly contributed to increasing concentrations and mobilizing U. In some places, the groundwater is supersaturated with uranyl-containing minerals, as would be expected in roll front deposits. In general, the interaction of natural geological sources high in U, the anthropogenically driven addition of HCO3 and possibly phosphate fertilizer, control the location and concentration of U in each individual fluvial fan, but the addition of nitrate in fertilizer does not appear control the location of high U. These geochemical interactions are complex but can be used to determine controls on anomalously high U in alluvial aquifers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-1694 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ rosen_anthropogenic_2019 Serial 158  
Permanent link to this record
 

 
Author Merembayev, T.; Yunussov, R.; Yedilkhan, A. url  openurl
  Title Machine Learning Algorithms for Stratigraphy Classification on Uranium Deposits Type Journal Article
  Year 2019 Publication Procedia Computer Science Abbreviated Journal  
  Volume 150 Issue Pages 46-52  
  Keywords (up) classification, geophysics logging data, machine learning, stratigraphy, uranium deposit  
  Abstract Machine learning today becomes more and more effective instrument to solve many particular problems, where there are difficulties to apply well known and described math model. In other words – it is a great tool to describe non-linear phenomena. We tried to use this technique to improve existing process of stratigraphy, and reduce costs on site by applying computer leaded predictions on the basis of existing on-field collected data. Article describes usage of machine learning algorithms for stratigraphy boundaries classification based on geophysics logging data for uranium deposit in Kazakhstan. Correct marking of stratigraphy from geophysics logging data is complex non-linear task. To solve this task we applied several algorithms of machine learning: random forest, logistic regression, gradient boosting, k nearest neighbour and XGBoost.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1877-0509 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ merembayev_machine_2019 Serial 113  
Permanent link to this record
 

 
Author Hebert, B.; Baron, F.; Robin, V.; Lelievre, K.; Dacheux, N.; Szenknect, S.; Mesbah, A.; Pouradier, A.; Jikibayev, R.; Roy, R.; Beaufort, D. url  openurl
  Title Quantification of coffinite (USiO4) in roll-front uranium deposits using visible to near infrared (Vis-NIR) portable field spectroscopy Type Journal Article
  Year 2019 Publication Journal of Geochemical Exploration Abbreviated Journal  
  Volume 199 Issue Pages 53-59  
  Keywords (up) Coffinite, Mineral quantification, Near infrared, Ore exploration, Portable field spectroscopy, Roll-front deposits  
  Abstract Coffinite (USiO4) is a common uranium-bearing mineral of roll-front uranium deposits. This mineral can be identified by the visible near infrared (Vis-NIR) portable field spectrometers used in mining exploration. However, due to the low detection limits and associated errors, the quantification of coffinite abundance in the mineralized sandstones or sandy sediments of roll-front uranium deposits using Vis-NIR spectrometry requires a specific methodological development. In this study, the 1135 nm absorption band area is used to quantify the abundance of coffinite. This absorption feature does not interfere with NIR absorption bands of any other minerals present in natural sands or sandstones of uranium roll-front deposits. The correlation between the 1135 nm band area and coffinite content was determined from a series of spectra measured from prepared mineral mixtures. The samples were prepared with a range of weighted amounts of arenitic sands and synthetic coffinite simulating the range of uranium concentration encountered in roll-front uranium deposits. The methodology presented in this study provides the quantification of the coffinite content present in sands between 0.03 wt% to 1 wt% coffinite with a detection limit as low as 0.005 wt%. The integrated area of the 1135 nm band is positively correlated with the coffinite content of the sand in this range, showing that the method is efficient to quantify coffinite concentrations typical of roll-front uranium deposits. The regression equation defined in this study was then used as a reference to predict the amount of natural coffinite in a set of mineralized samples from the Tortkuduk uranium roll-front deposit (South Kazakhstan).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0375-6742 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ hebert_quantification_2019 Serial 184  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: