Gramsbergen-NL: May 2019
Uranium is a widespread and ubiquitous element. It has a crustal abundance of 2.8 parts per million, slightly more than tin. Primary deposits of uranium tend to concentrate in granitic or alkalic volcanic rocks, hydrothermal veins, marine black shales, and Precambrian age placers.
Secondary (or epigenetic) deposits of uranium are formed later than the surrounding rocks that host the mineral deposit. Uranium is soluble in oxidizing aqueous solutions, especially the U+6 valence state, and can be redistributed from primary source rocks into porous sedimentary rocks and structures by groundwater and form secondary(epigenetic) uranium mineral deposits.
Organic material in the pore spaces of rocks create a reducing environment in the water. The oxidizing, uranium-bearing waters passing through the rock precipitate uranium in the rock where the reducing environment exists. Sometimes whole logs (organic matter) buried in the rocks become rich in uranium deposited through this process. This process is what allows in-situ mining of the uranium. Humans pump oxidizing water into the uranium ore, dissolve it, and bring the solution to the surface and precipitate out the uranium.
in-situ mining can be done with the WROP-MAC System combination.
Haltin has made the first Well-Layout proposals to reduce the present production costs and increase the Production volume.
Further studies are ongoiing to inject used nuclear waiste into the same in-situ area again.