Distribution Of Groundwater U3O8 On The Colorado Plateau

Leaching of a granitic rock mass by slightly acid groundwater brings uranium and genetically related ions into solution in groundwater. Uranium and related ions are moved through the vadose zone by groundwater which in turn moves through zones of greatest transmissivity into a deep zone of increased hydrostatic pressure. Cyclic wetting causes the hydrostatic condition to fluctuate causing recycling described by Gruner (op cit). Multiple cycling flushes the uranium ions from rock being leached and moves it via this method to permeable beds-channels-in the deep zone.