Uranium speciation in calcites from deep crystalline rock environment, Forsmark, Sweden

During the siting of a geological repository for spent nuclear fuel (SNF), low and intermediate level nuclear waste (SFR) in Sweden,
significantly elevated uranium (U) concentration was found in a 500 m deep groundwater (GW) in Forsmark located on the Baltic Sea coast,
eastern Sweden. The main aim of the experiment is to determine uranium (U) redox state of U in a U-rich
calcites precipitated at anoxic conditions at 400-500 m depth during the 18-year experiment conducted at Forsmark site, Sweden. More
specifically we aim to determine U sequestration and speciation on borehole equipment collected from different deep bedrock sections,
corresponding to U-rich groundwater circulation zones.