Anthropogenic Induced Redox Disequilibrium in Uranium Ore Zones

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Anthropogenic Induced Redox Disequilibrium in
UraniumOre Zones

• Richard Abitz, Savannah River National Laboratory
  Bruce Darling, Southwest Groundwater Consulting,
  LLC

GSA 2010, Denver, Colorado
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Drilling Issues Related to Redox
Disequilibrium Physical change to the ore
minerals
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Drilling Issues Related to Redox
Disequilibrium Chemical reactions in the ore
zone 7/2O2 H2O FeS2 ? 2H Fe 2SO4--
½O2 2H UO2 ? H2O UO2 Airlift
purge and pump adds O2
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Mineral Dissolution Rates General form of rate
law (Lasaga, 1995)1 Rate k0Amine-Ea/RTanH
g(I)?ianif(?Gr) Increase in both surface
area (Amin) and O2 activity (anO2) will
increase dissolution rate. 1 Lasaga, A.C.,
1995, Fundamental Approaches in Describing
Mineral Dissolution and Precipitation
Reactions, in Reviews in Mineralogy, Volume
31, Chemical Weathering Rates of Silicate
Minerals, Mineralogical Society of America.
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(No Transcript)
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UEC Permit UR03075
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UEC Permit UR03075 Initial ISL target is B Sand,
yellow pattern
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Production Test Wells (PTW), Sand B
URANIUM Apr 2008 0.005 to 0.804
mg/L July 2009 lt0.003 to 0.090
mg/L Nov 2009 lt0.003 to 0.010 mg/L
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Production Test Wells (PTW), Sand B
ARSENIC Apr 2008 0.001 to 0.022
mg/L July 2009 lt0.010 mg/L Nov
2009 lt0.010 mg/L
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Production Test Wells (PTW), Sand B
FUORIDE Apr 2008 0.50 to 0.79 mg/L July
2009 0.50 to 0.54 mg/L Nov 2009 0.50 to
0.69 mg/L
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Production Test Wells (PTW), Sand B
RADIUM Apr 2008 10 to 1,680 pCi/L July
2009 17 to 2,000 pCi/L Nov 2009 10 to
1,590 pCi/L
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B Monitor Wells (BMW), Sand B
URANIUM Apr 2008 lt0.001 to 0.188
mg/L July 2009 lt0.003 to 0.006
mg/L Nov 2009 lt0.003 mg/L
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B Monitor Wells (BMW), Sand B
ARSENIC Apr 2008 0.001 to 0.069
mg/L July 2009 lt0.010 mg/L Nov
2009 lt0.010 mg/L
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B Monitor Wells (BMW), Sand B
RADIUM Apr 2008 0.90 to 41 pCi/L July
2009 1.3 to 48 pCi/L Nov 2009 0.10 to 40
pCi/L
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Overlying Monitor Wells (OMW), Sand A
URANIUM Apr 2008 0.006 to 0.014
mg/L July 2009 0.003 to 0.013 mg/L Nov
2009 0.009 to 0.012 mg/L
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Overlying Monitor Wells (OMW), Sand A
ARSENIC Apr 2008 0.010 to 0.031
mg/L July 2009 0.005 to 0.010 mg/L Nov
2009 0.005 to 0.010 mg/L
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Overlying Monitor Wells (OMW), Sand A
RADIUM Apr 2008 0.5 to 6.0 pCi/L July
2009 0.2 to 3.2 pCi/L Nov 2009 0.4 to 1.0
pCi/L
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Uranium solubility as a function of Eh